ALBERT

Beschreibung: When cumulonimbus clouds aggregate, developing into a single entity with precipitation covering a horizontal scale of hundreds of kilometers, they are called mesoscale convective systems (MCSs). They account for much of Earth’s precipitation, generate severe weather events and flooding, produce prodigious cirriform anvil clouds, and affect the evolution of the larger-scale circulation. Understanding the inner workings of MCSs has resulted from developments in observational technology and modeling. Time–space conversion of ordinary surface and upper-air observations provided early insight into MCSs, but deeper understanding has followed field campaigns using increasingly sophisticated radars, better aircraft instrumentation, and an ever-widening range of satellite instruments, especially satellite-borne radars. High-resolution modeling and theoretical insights have shown that aggregated cumulonimbus clouds induce a mesoscale circulation consisting of air overturning on a scale larger than the scale of individual convective up- and downdrafts. These layers can be kilometers deep and decoupled from the boundary layer in elevated MCSs. Cooling in the lower troposphere and heating aloft characterize the stratiform regions of MCSs. As a result, long-lived MCSs with large stratiform regions have a top-heavy heating profile that generates potential vorticity in midlevels, thus influencing the larger-scale circulation within which the MCSs occur. Global satellite data show MCSs varying in structure, depending on the prevailing large-scale circulation and topography. These patterns are likely to change with global warming. In addition, environmental pollution affects MCS structure and dynamics subtly. Feedbacks of MCSs therefore need to be included or parameterized in climate models.

Beschreibung: The microphysical processes inside convective clouds play an important role in climate. They directly control the amount of detrainment of cloud hydrometeor and water vapor from updrafts. The detrained water substance in turn affects the anvil cloud formation, upper-tropospheric water vapor distribution, and thus the atmospheric radiation budget. In global climate models, convective parameterization schemes have not explicitly represented microphysics processes in updrafts until recently. In this paper, the authors provide a review of existing schemes for convective microphysics parameterization. These schemes are broadly divided into three groups: tuning-parameter-based schemes (simplest), single-moment schemes, and two-moment schemes (most comprehensive). Common weaknesses of the tuning-parameter-based and single-moment schemes are outlined. Examples are presented from one of the two-moment schemes to demonstrate the performance of the scheme in simulating the hydrometeor distribution in convection and its representation of the effect of aerosols on convection.

Beschreibung: The central change in understanding of the ocean circulation during the past 100 years has been its emergence as an intensely time-dependent, effectively turbulent and wave-dominated, flow. Early technologies for making the difficult observations were adequate only to depict large-scale, quasi-steady flows. With the electronic revolution of the past 50+ years, the emergence of geophysical fluid dynamics, the strongly inhomogeneous time-dependent nature of oceanic circulation physics finally emerged. Mesoscale (balanced), submesoscale oceanic eddies at 100-km horizontal scales and shorter, and internal waves are now known to be central to much of the behavior of the system. Ocean circulation is now recognized to involve both eddies and larger-scale flows with dominant elements and their interactions varying among the classical gyres, the boundary current regions, the Southern Ocean, and the tropics.

Beschreibung: The authors present an observationally based evaluation of the vertically resolved cloud ice water content (CIWC) and vertically integrated cloud ice water path (CIWP) as well as radiative shortwave flux downward at the surface (RSDS), reflected shortwave (RSUT), and radiative longwave flux upward at top of atmosphere (RLUT) of present-day global climate models (GCMs), notably twentieth-century simulations from the fifth phase of the Coupled Model Intercomparison Project (CMIP5), and compare these results to those of the third phase of the Coupled Model Intercomparison Project (CMIP3) and two recent reanalyses. Three different CloudSat and/or Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) combined ice water products and two methods are used to remove the contribution from the convective core ice mass and/or precipitating cloud hydrometeors with variable sizes and falling speeds so that a robust observational estimate can be obtained for model evaluations. The results show that, for annual mean CIWC and CIWP, there are factors of 2–10 (either over- or underestimate) in the differences between observations and models for a majority of the GCMs and for a number of regions. Most of the GCMs in CMIP3 and CMIP5 significantly underestimate the total ice water mass because models only consider suspended cloud mass, ignoring falling and convective core cloud mass. For the annual means of RSDS, RLUT, and RSUT, a majority of the models have significant regional biases ranging from −30 to 30 W m−2. Based on these biases in the annual means, there is virtually no progress in the simulation fidelity of RSDS, RLUT, and RSUT fluxes from CMIP3 to CMIP5, even though there is about a 50% bias reduction improvement of global annual mean CIWP from CMIP3 to CMIP5. It is concluded that at least a part of these persistent biases stem from the common GCM practice of ignoring the effects of precipitating and/or convective core ice and liquid in their radiation calculations.

Beschreibung: Yanai and coauthors utilized the meteorological data collected from a sounding network to present a pioneering work in 1973 on thermodynamic budgets, which are referred to as the apparent heat source (Q1) and apparent moisture sink (Q2). Latent heating (LH) is one of the most dominant terms in Q1. Yanai’s paper motivated the development of satellite-based LH algorithms and provided a theoretical background for imposing large-scale advective forcing into cloud-resolving models (CRMs). These CRM-simulated LH and Q1 data have been used to generate the look-up tables in Tropical Rainfall Measuring Mission (TRMM) LH algorithms. A set of algorithms developed for retrieving LH profiles from TRMM-based rainfall profiles is described and evaluated, including details concerning their intrinsic space–time resolutions. Included in the paper are results from a variety of validation analyses that define the uncertainty of the LH profile estimates. Also, examples of how TRMM-retrieved LH profiles have been used to understand the life cycle of the MJO and improve the predictions of global weather and climate models as well as comparisons with large-scale analyses are provided. Areas for further improvement of the TRMM products are discussed.

Beschreibung: The authors survey a series of modeling studies that have examined the influences that cloud microphysical processes can have on tropical cyclone (TC) motion, the strength and breadth of the wind field, inner-core diabatic heating asymmetries, outer-core convective activity, and the characteristics of the TC anvil cloud. These characteristics are sensitive to the microphysical parameterization (MP) in large part owing to the cloud-radiative forcing (CRF), the interaction of hydrometeors with radiation. The most influential component of CRF is that due to absorption and emission of longwave radiation in the anvil, which via gentle lifting directly encourages the more extensive convective activity that then leads to a radial expansion of the TC wind field. On a curved Earth, the magnitude of the outer winds helps determine the speed and direction of TC motion via the beta drift. CRF also influences TC motion by determining how convective asymmetries develop in the TC inner core. Further improvements in TC forecasting may require improved understanding and representation of cloud-radiative processes in operational models, and more comprehensive comparisons with observations are clearly needed.

Beschreibung: The Asian monsoon is a planetary-scale circulation system powered by the release of latent heat, but important features of deep convection and rainfall distribution cannot be adequately represented by the large-scale patterns. This is mainly due to the strong influences of terrain that are important across a wide range of horizontal scales, especially over the Maritime Continent where the complex terrain has a dominant effect on the behavior of convective rainfall during the boreal winter monsoon. This chapter is a review and summary of published results on the effects on monsoon convection due to interactions between the Maritime Continent terrain and large-scale transient systems. The Maritime Continent topographic features strongly affect both the demarcation of the boreal summer and winter monsoon regimes and the asymmetric seasonal marches during the transition seasons. In the western part of the region, the complex interactions that lead to variability in deep convection are primarily controlled by the cold surges and the synoptic-scale Borneo vortex. The Madden–Julian oscillation (MJO) reduces the frequency of weaker surges through an interference with their structure. It also influences convection, particularly on the diurnal cycle and when synoptic activities are weak. When both surges and the Borneo vortex are present, interactions between these circulations with the terrain can cause the strongest convection, which has included Typhoon Vamei (2001), which is the only observed tropical cyclone that developed within 1.5° of the equator. The cold surges are driven by midlatitude pressure rises associated with the movement of the Siberian high. Rapid strengthening of surge northeasterly winds can be explained as the tropical response via a geostrophic adjustment process to the pressure forcing in the form of an equatorial Rossby wave group. Dispersion of meridional modes leads to a northeast–southwest orientation that allows the surge to stream downstream through the similarly oriented South China Sea. This evolution leads to a cross-equatorial return flow and a cyclonic circulation at the equator, and thus a mechanism for equatorial cyclogenesis. Although the narrow width of the southern South China Sea facilitates strengthening of the cold surge, it also severely restricts the likelihood of cyclone development so that Vamei remains to be the only typhoon observed in the equatorial South China Sea. Climate variations from El Niño–Southern Oscillation to climate change may impact the interactions between the large-scale motion and Maritime Continent terrain because they lead to changes in the mean flow. The thermodynamic effects on the interaction between MJO and the monsoon surges and Borneo vortex over the complex terrain also need to be addressed. These and other questions such as any possible changes in the likelihood of equatorial tropical cyclogenesis as a result of climate change are all important areas for future research.

Beschreibung: Insights by Professor Michio Yanai on tropical waves, which have been vital ingredients for progress in tropical meteorology over the last half-century, are recollected. This study revisits various aspects of research on tropical waves over the last five decades to examine, in Yanai’s words, “the nature of ‘A-scale’ tropical wave disturbances and the interaction of the waves and the ‘B-scale’ phenomena (cloud clusters),” the fundamental problem posed by Yanai at the design phase of the GARP Atlantic Tropical Experiment (GATE) in 1971. The various contributions of Michio Yanai to the current understanding of the dynamics of the tropical atmosphere are briefly reviewed to show how his work has led to several current theories in this field.

Beschreibung: Although atmospheric observing systems were already an important part of meteorology before the American Meteorological Society was established in 1919, the past 100 years have seen a steady increase in their numbers and types. Examples of how observing systems were developed and how they have enabled major scientific discoveries are presented. These examples include observing systems associated with the boundary layer, the upper air, clouds and precipitation, and solar and terrestrial radiation. Widely used specialized observing systems such as radar, lidar, and research aircraft are discussed, and examples of applications to weather forecasting and climate are given. Examples drawn from specific types of chemical measurements, such as ozone and carbon dioxide, are included. Sources of information on observing systems, including other chapters of this monograph, are also discussed. The past 100 years has been characterized by synergism between societal needs for weather observations and the needs of fundamental meteorological research into atmospheric processes. In the latter half of the period, observing system improvements have been driven by the increasing demands for higher-resolution data for numerical models, the need for long-term measurements, and for more global coverage. This has resulted in a growing demand for data access and for integrating data from an increasingly wide variety of observing system types and networks. These trends will likely continue.

Beschreibung: The polar regions present several unique challenges to meteorology, including remoteness and a harsh environment. We summarize the evolution of polar meteorology in both hemispheres, beginning with measurements made during early expeditions and concluding with the recent decades in which polar meteorology has been central to global challenges such as the ozone hole, weather prediction, and climate change. Whereas the 1800s and early 1900s provided data from expeditions and only a few subarctic stations, the past 100 years have seen great advances in the observational network and corresponding understanding of the meteorology of the polar regions. For example, a persistent view in the early twentieth century was of an Arctic Ocean dominated by a permanent high pressure cell, a glacial anticyclone. With increased observations, by the 1950s it became apparent that, while anticyclones are a common feature of the Arctic circulation, cyclones are frequent and may be found anywhere in the Arctic. Technology has benefited polar meteorology through advances in instrumentation, especially autonomously operated instruments. Moreover, satellite remote sensing and computer models revolutionized polar meteorology. We highlight the four International Polar Years and several high-latitude field programs of recent decades. We also note outstanding challenges, which include understanding of the role of the Arctic in variations of midlatitude weather and climate, the ability to model surface energy exchanges over a changing Arctic Ocean, assessments of ongoing and future trends in extreme events in polar regions, and the role of internal variability in multiyear-to-decadal variations of polar climate.

Beschreibung: It is well known that the envelope of the Madden–Julian oscillation (MJO) consists of smaller-scale convective systems, including mesoscale convective systems (MCS), tropical cyclones, and synoptic-scale waves called “convectively coupled equatorial waves” (CCW). In fact, recent results suggest that the fundamental mechanisms of the MJO involve interactions between the synoptic-scale CCW and their larger-scale environment (Majda and Stechmann). In light of this, this chapter reviews recent and past work on two-way interactions between convective systems—both MCSs and CCW—and their larger-scale environment, with a particular focus given to recent work on MJO–CCW interactions.

Beschreibung: This volume consists of some papers presented at the AMS Symposium held to honor the memory of the late Professor Michio Yanai as well as additional works inspired by his research. By the nature of this volume, many of the contributed papers describe the development of tropical meteorology over the past half-century or so in connection with Professor Yanai’s influence on it. While most of the chapters address specific areas and discuss timely issues, in this prologue I will describe some of Professor Yanai’s contributions during the early period of his career from my own point of view. As this is a personal reminiscence, I would like to emphasize how Professor Yanai influenced me. Both Professor Yanai and I became graduate students at the University of Tokyo to begin our career as meteorologists in 1956 and 1957, respectively. Since we studied and worked together so closely for a long time, in this article I will call him Yanai-san as I have done in our personal interactions.

Beschreibung: This chapter reviews Professor Michio Yanai’s contributions to the discovery and science of the Madden–Julian oscillation (MJO). Professor Yanai’s work on equatorial waves played an inspirational role in the MJO discovery by Roland Madden and Paul Julian. Professor Yanai also made direct and important contributions to MJO research. These research contributions include work on the vertically integrated moist static energy budget, cumulus momentum transport, eddy available potential energy and eddy kinetic energy budgets, and tropical–extratropical interactions. Finally, Professor Yanai left a legacy through his students, who continue to push the bounds of MJO research.

Beschreibung: Two features of Yanai et al.’s profiles of Q1 and Q2—the commonly observed double-peak structure to Q2 and an inflection in the Q1 profile below the melting level—are explored using estimates of convective and stratiform rainfall partitioning based on Massachusetts Institute of Technology (MIT) radar reflectivity data collected during TOGA COARE. The MIT radar data allow the Q1 and Q2 profiles to be classified according to stratiform rain fraction within the radar domain and, within the limitations of the datasets, allow interpretations to be made about the relative contributions of convective and stratiform precipitation to the mean profiles. The sorting of Q2 by stratiform rain fraction leads to the confirmation of previous findings that the double-peak structure in the mean profile is a result of a combination of separate contributions of convective and stratiform precipitation. The convective contribution, which has a drying peak in the lower troposphere, combines with a stratiform drying peak aloft and low-level moistening peak to yield a double-peak structure. With respect to the inflection in the Q1 profile below the 0°C level, this feature appears to be a manifestation of melting. It is the significant horizontal dimension of the stratiform components of tropical convective systems that yields a small but measurable imprint on the large-scale temperature and moisture stratification upon which the computations of Q1 and Q2 are based. The authors conclude, then, that the rather subtle features in the Q1/Q2 profiles of Yanai et al. are directly linked to the prominence of stratiform precipitation within tropical precipitation systems.

Beschreibung: This monograph on convection-coupled systems in the tropics was inspired by the life and career of Professor Michio Yanai, whose major contributions to the subject spanned more than five decades. From a distant perspective, Professor Yanai’s career can be understood in the context of Japanese scientists who immigrated to the United States in the decades of the 1950s and 1960s, enriching the meteorological research community in the United States as well as abroad (Lewis 1993). A closer look reminds us that the tapestry of scientific progress is created by the contributions of individual scientists with their unique backgrounds, motivations, and talents, and the serendipity of events that shape their lives.

Beschreibung: Professor Yanai is remembered in our hearts as an esteemed friend. Based on his accomplishments in tropical meteorology and with his flashes of insight he led his group at the University of California, Los Angeles, in the 1980s and 1990s to explore the thermal features of the Tibetan Plateau (TP) and its relation to the Asian monsoon, and he brought forward the TP meteorology established by Ye Duzheng et al. in 1957 to a new stage. In cherishing the memory of Professor Yanai and his great contribution to the TP meteorology, the authors review their recent study on the impacts of the TP and contribute this chapter as an extension of their chapter titled “Effects of the Tibetan Plateau” published by Yanai and Wu in 2006 in the book The Asian Monsoon. The influence of a large-scale orography on climate depends not only on the mechanical and thermal forcing it exerts on the atmosphere, but also on the background atmospheric circulation. In winter the TP possesses two leading heating modes resulting from the relevant dominant atmospheric circulations, in particular the North Atlantic Oscillation and the North Pacific Oscillation. The prevailing effect of the mechanical forcing of the TP in wintertime generates a dipole type of circulation, in which the anticyclonic gyre in the middle and high latitudes contributes to the warm inland area to the west, and the cold seashore area to the east, of northeast Asia, whereas the cyclonic gyre in low latitudes contributes to the formation of a prolonged dry season over central and southern Asia and moist climate over southeastern Asia. Such a dipole circulation also generates a unique persistent rainfall in early spring (PRES) over southern China. In 1980s, Yanai and his colleagues analyzed the in situ observation and found that the constant potential temperature boundary layer over the TP can reach about 300 hPa before the summer monsoon onset. This study supports these findings, and demonstrates that such a boundary layer structure is a consequence of the atmospheric thermal adaptation to the surface sensible heating, which vanishes quickly with increasing height. The overshooting of rising air, which is induced by surface sensible heating, then can form a layer of constant potential temperature with a thickness of several kilometers. The thermal forcing of the TP on the lower tropospheric circulation looks like a sensible heat–driven air pump (SHAP). It is the surface sensible heating on the sloping sides of the plateau that the SHAP can effectively influence the Asian monsoon circulation. In spring the SHAP contributes to the seasonal abrupt change of the Asian circulation and anchors the earliest Asian summer monsoon onset over the eastern Bay of Bengal. In summer, this pumping, together with the thermal forcing over the Iranian Plateau, produces bimodality in the South Asian high activity in the upper troposphere, which is closely related to the climate anomaly patterns over South and East Asia. Because the isentropic surfaces in the middle and lower troposphere intersect with the TP, in summertime the plateau becomes a strong negative vorticity source of the atmosphere and affects the surrounding climate and even the Northern Hemispheric circulation via Rossby wave energy dispersion. Future prospects in related TP studies are also addressed.

Beschreibung: In this chapter, a model parameterization for organized tropical convection and convectively coupled tropical waves is presented. The model is based on the main three cloud types, congestus, deep, and stratiform, that are observed to play an important role in the dynamics and morphology of tropical convective systems. The model is based on the self-similarity across scales of tropical convective systems and uses physically sound theory about the mutual interactions between the three cloud types and the environment. Both linear analysis and numerical simulations of convectively coupled waves and the Madden–Julian oscillation are discussed.

Beschreibung: The field of atmospheric science has been enhanced by its long-standing collaboration with entities with specific needs. This chapter and the two subsequent ones describe how applications have worked to advance the science at the same time that the science has served the needs of society. This chapter briefly reviews the synergy between the applications and advancing the science. It specifically describes progress in weather modification, aviation weather, and applications for security. Each of these applications has resulted in enhanced understanding of the physics and dynamics of the atmosphere, new and improved observing equipment, better models, and a push for greater computing power.

Beschreibung: The authors examined the maintenance mechanisms of perturbation kinetic energy (PKE) in the tropical regions for multiple time scales by computing and analyzing its budget equation. The emphasis has been placed on the mean features of synoptic and subseasonal variabilities using a 33-yr dataset. From analysis of the contributions from u-wind and υ-wind components, the PKE maximum in the Indian Ocean is attributed less to synoptic variability and more to intraseasonal variability in which the Madden–Julian oscillation (MJO) dominates; however, there is strong evidence of seasonal variability affiliated with the Asian monsoon systems. The ones in the eastern Pacific and Atlantic Oceans are closely related to both intraseasonal and synoptic variability that result from the strong MJO and the relatively large amplitude of equatorial waves. The maintenance of the PKE budget mainly depends on the structure of time mean horizontal flows, the location of convection, and the transport of PKE from the extratropics. In the regions with strong convective activities, such as the eastern Indian Ocean to the western Pacific, the production of PKE occurs between 700 and 200 hPa at the expense of perturbation available potential energy (PAPE), which is generated by convective heating. This gain in PKE is largely offset by divergence of the geopotential component of vertical energy flux; that is, it is redistributed to the upper- and lower-atmospheric layers by the pressure field. Strong PKE generation through the horizontal convergence of the extratropical energy flux takes place in the upper troposphere over the eastern Pacific and Atlantic Ocean, and is largely balanced by a PKE loss due to barotropic conversion, which is determined solely by the sign of longitudinal stretching deformation. However, over the Indian Ocean, there is a net PKE loss due to divergence of energy flux, which is compensated by PKE gain through the shear generation.

Beschreibung: Over the past century, the atmospheric and related sciences have seen incredible advances in our understanding of Earth’s environment and our ability to monitor and predict its behavior. These advances have had a profound impact on society and have been integrated into every aspect of daily life. The American Meteorological Society (AMS) has been instrumental in supporting these advances throughout its first 100 years of existence as a scientific and professional society serving the community of professionals in the atmospheric and related oceanic and hydrologic sciences. AMS has provided opportunities for researchers and practitioners to share their scientific findings and build fruitful collaborations to further the science and its application. Through strategic initiatives at key points in its history, AMS has pushed the science forward—highlighting areas ripe for development, creating frameworks for interdisciplinary interactions, and providing innovative approaches to the dissemination of research results. As a society made up of the scientific community and led by many of the most prominent scientists of their time, AMS has been able to respond to, and often anticipate, the needs of its community.

Beschreibung: One of the most important contributions of Michio Yanai to tropical meteorology is the introduction of the concepts of apparent heat source Q1 and apparent moisture sink Q2 in the large-scale heat and moisture budgets of the atmosphere. Through the inclusion of unresolved eddy effects, the vertical profiles of apparent sources (and sinks) are generally quite different from those of true sources taking place locally. In low-resolution models, such as the conventional general circulation models (GCMs), cumulus parameterization is supposed to determine the apparent sources for each grid cell from the explicitly predicted grid-scale processes. Because of the recent advancement of computer technology, however, increasingly higher horizontal resolutions are being used even for studying the global climate, and, therefore, the concept of apparent sources must be expanded rather drastically. Specifically, the simulated apparent sources should approach and eventually converge to the true sources as the horizontal resolution is refined. For this transition to take place, the conventional cumulus parameterization must be either generalized so that it is applicable to any horizontal resolutions or replaced with the mean effects of cloud-scale processes explicitly simulated by a cloud-resolving model (CRM). These two approaches are called ROUTE I and ROUTE II for unifying low- and high-resolution models, respectively. This chapter discusses the conceptual and technical problems in exploring these routes and reviews the authors’ recent work on these subjects.

Beschreibung: This chapter proposes a working assumption as a way of conceptual simplification of the origin of Madden–Julian oscillation (MJO)-associated convection, or super cloud cluster (SCC). To develop the simplification, the importance of the synoptic-scale cold reservoir underlying the convection and its interaction with the accompanying zonal–vertical circulation is highlighted. The position of the convection with respect to that of climatological warm pool is postulated to determine the effectiveness of this framework. The authors introduce a prototype hypothesis to illustrate the usefulness of the above assumption based on a numerical simulation experiment with a global nonhydrostatic model for the boreal summer season. Premises for the hypothesis include 1) that the cloud cluster (CC) is a basic building block of tropical convection accompanying the precipitation-generated cold reservoir in its subcloud layer and 2) that a warm-pool-induced quasi-persistent zonal circulation is key for the upscale organization of CCs. The theory of squall-line structure by Rotunno, Klemp, and Weisman (hereafter RKW) is employed for the interpretation. No account is taken regarding the influences of equatorial waves as a first-order approximation. Given the premises, an SCC of O(1000) km scale is interpretable as a gigantic analog of a multicellular squall line embedded in the quasi-stationary westerly shear branch of the zonal circulation east of the warm water pool. A CC corresponds to the “cell,” and its successive formation to the east and westward movement represents an upshear-tilting core of intense updraft. The upshear-tilted SCC is favorably maintained with the precipitating area being separated from the gust front boundary between the cold reservoir and a low-level easterly, which is supported in the realm of the RKW theory where two horizontal vortices associated with the cold reservoir and vertical shear are opposite in sign but cold reservoir’s vorticity can be inferred to be larger, leading to upshear-tilted and multicellular behavior. As a counterexample, CCs to the west of the warm pool (Indian Ocean and Arabian Sea) are embedded in the easterly shear and organized into a less coherent cloud cluster complex (CCC) given the situation of RKW where two horizontal vortices associated with the cold reservoir and vertical shear are still opposite in sign, but the smaller vertical shear west of the warm pool causes even more suboptimal vorticity imbalance in the western flank of cold reservoir, leading to larger tilt with height and intermittent, less viable storm situations. A cold pool or cold reservoir, having been prevalent in mesoscale convection research, is argued to be important for the MJO as pointed out by the emerging evidence in the international field campaign for the MJO called Cooperative Indian Ocean Experiment on Intraseasonal Variability (CINDY)/DYNAMO. The simplified and idealistic hypothesis proposed here does not cover all aspects of MJO and its validation awaits further modeling and observational studies, but it can offer a framework for characterizing a fundamental aspect of the origin of MJO-associated convection.

Beschreibung: This chapter distinguishes the mechanism of tropical convective disturbances, such as a hurricane, from that of the Madden–Julian oscillation (MJO). The hurricane is maintained by organized convection around the azimuth. In a hurricane the organization of convection, the generation of eddy available potential energy, and the transformation of eddy available potential energy into eddy kinetic energy all occur on the scale of the hurricane and these are called “in-scale processes,” which invoke quadratic nonlinearity. The MJO is not a hurricane type of disturbance; organized convection simply does not drive an MJO in the same manner. The maintenance of the MJO is more akin to a multibody problem where the convection is indeed organized on scales of tropical synoptic disturbances that carry a similar organization of convection and carry similar roles for the generation of eddy available potential energy and its conversion to the eddy kinetic energy for their maintenance. The maintenance of the MJO is a scale interaction problem that comes next, where pairs of synoptic-scale disturbances are shown to interact with a member of the MJO time scale, thus contributing to its maintenance. This chapter illustrates the organization of convection, synoptic-scale energetics, and nonlinear scale interactions to show the above aspects for the mechanism of the MJO.

Beschreibung: Cloud processes play a central role in the dynamics of the tropical atmosphere, but for many years the shortcomings of cloud parameterizations have limited our ability to simulate and understand important tropical weather systems such as the Madden–Julian oscillation. Since about 2001, “superparameterization” has emerged as a new path forward, complementing but not replacing studies based on conventional parameterizations. This chapter provides an overview of work with superparameterization, including a discussion of the method itself and a summary of key results.

Beschreibung: A century ago, meteorologists regarded tropical cyclones as shallow vortices, extending upward only a few kilometers into the troposphere, and nothing was known about their physics save that convection was somehow involved. As recently as 1938, a major hurricane struck the densely populated northeastern United States with no warning whatsoever, killing hundreds. In the time since the American Meteorological Society was founded, however, tropical cyclone research blossomed into an endeavor of great breadth and depth, encompassing fields ranging from atmospheric and oceanic dynamics to biogeochemistry, and the precision and scope of forecasts and warnings have achieved a level of success that would have been regarded as impossible only a few decades ago. This chapter attempts to document the extraordinary progress in tropical cyclone research over the last century and to suggest some avenues for productive research over the next one.

Beschreibung: Publication date: Available online 9 July 2016 Source: Geodesy and Geodynamics Author(s): Ruisha Li, Xi Zhang, Shouwen Gong, Hongtao Tang, Peng Jia The equation for determining cross-fault representative value is calculated based on hanging wall and foot wall reference level surfaces. The cross-fault data reliability are analyzed base on the stability of reference datum and observation points, thereby facilitating plotting of the representative value curves after removing interference. The spatial and temporal characteristics of fault deformation abnormalities before the 2016 Menyuan M s6.4 earthquake, as well as the fault-movement characteristics reflected by representative value, are summarized. The results show that many site trends had changed 1–3 years before the Menyuan M s6.4 earthquake in the Qilian Fault, reflecting certain background abnormalities. The short-term abnormalities centrally had appeared in the 6 months to 1 year period before the earthquake near and in the neighborhood of the source region, demonstrating a significantly increased number of short-term abnormalities. Many sites near and in the neighborhood of the source region had strengthened inverse activities or had changed from positive to inverse activities in the most recent 2–3 years, which reflect stress-field enhancements or adjustment features.

Beschreibung: Publication date: Available online 22 July 2016 Source: Advances in Climate Change Research Author(s): H.E. Jian-Kun The Paris Agreement establishes a new mechanism for post-2020 global climate governance, and sets long-term goals for global response to climate change, which will accelerate worldwide low-carbon transformation of economic development pattern, promote the revolutionary reform of energy system, boost a fundamental change in the mode of social production and consumption, and further the civilization of human society from industrial civilization to eco-civilization. The urgency of global low-carbon transition will reshape the competition situation of world’s economy, trade and technology. Taking the construction of eco-civilization as a guide, China explores green and low-carbon development paths, establishes ambitious intended nationally determined contribution (INDC) targets and action plans, advances energy production and consumption revolution, and speeds up the transformation of economic development pattern. These strategies and actions not only confirm to the trend of the world low-carbon transition, but also meet the intrinsic requirements for easing the domestic resources and environment constraints and realizing sustainable development. They are multi-win-win strategies for promotion of economic development and environmental protection and mitigation of carbon emissions. China should take the global long-term emission reduction targets as a guide, and formulate medium and long-term low-carbon development strategy, build the core competitiveness of low-carbon advanced technology and development pattern, and take an in-depth part in global governance so as to reflect the responsibility of China as a great power in constructing a community of common destiny for all mankind and addressing global ecological crisis.

Beschreibung: Publication date: Available online 28 July 2016 Source: Geoscience Frontiers Author(s): Yusuke Imaeda, Toshikazu Ebisuzaki In the tandem planet formation regime, planets form at two distinct sites where solid particles are densely accumulated due to the on/off state of the magnetorotational instability (MRI).We found that tandem planet formation can reproduce the solid component distribution of the Solar System and tends to produce a smaller number of large planets through continuous pebble ow into the planet formation sites. In the present paper, we investigate the dependence of tandem planet formation on the vertical magnetic field of the protoplanetary disk. We calculated two cases of B z = 3 . 4 × 10 -3 G and B z = 3 . 4 × 10 -5 G at 100 AU as well as the canonical case of B z = 3 . 4 × 10 -4 G. We found that tandem planet formation holds up well in the case of the strong magnetic _eld ( B z = 3 . 4 × 10 -3 G). On the other hand, in the case of a weak magnetic _eld ( B z = 3 . 4 × 10 -5 G) at 100 AU, a new regime of planetary growth is realized: the planets grow independently at different places in the dispersed area of the MRI-suppressed region of r = 8 - 30 AU at a lower accretion rate of Ṁ 〈 10 -7 . 4 M⊙ yr -1 . We call this the "dispersed planet formation" regime. This may lead to a system with a larger number Graphical abstract

Beschreibung: Publication date: Available online 19 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Aref al-Swaidani, Ibrahim Hammoud, Ayman Meziab Clayey soils in Syria cover a total area of more than 20,000 km 2 of the country, most of which are located in the southwestern region. In many places of the country, the clayey soils caused severe damage to infrastructures. Extensive studies have been carried out on the stabilization of clayey soils using lime. Syria is rich in both lime and natural pozzolana. However, few works have been conducted to investigate the influence of adding natural pozzolana on the geotechnical properties of lime-treated clayey soils. The aim of this paper is to understand the effect of adding natural pozzolana on some geotechnical properties of lime-stabilized clayey soils. Natural pozzolana and lime are added to soil within the range of 0%−20% and 0%−8%, respectively. Consistency, compaction, California bearing ratio (CBR) and linear shrinkage properties are particularly investigated. The test results show that the investigated properties of lime-treated clayey soils can be considerably enhanced when the natural pozzolana is added as a stabilizing agent. Analysis results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) show significant changes in the microstructure of the treated clayey soil. A better flocculation of clayey particles and further formation of cementing materials in the natural pozzolana-lime-treated clayey soil are clearly observed.

Beschreibung: Publication date: Available online 15 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Sadok Benmebarek, Samir Attallaoui, Naïma Benmebarek Back-to-back mechanically stabilized earth walls (BBMSEWs) are encountered in bridge approaches, ramp ways, rockfall protection systems, earth dams, levees and noise barriers. However, available design guidelines for BBMSEWs are limited and not applicable to numerical modeling when back-to-back walls interact with each other. The objective of this paper is to investigate, using PLAXIS code, the effects of the reduction in the distance between BBMSEW, the reinforcement length, the quality of backfill material and the connection of reinforcements in the middle, when the back-to-back walls are close. The results indicate that each of the BBMSEWs behaves independently if the width of the embankment between mechanically stabilized earth walls is greater than that of the active zone. This is in good agreement with the result of FHWA design guideline. However, the results show that the FHWA design guideline underestimates the lateral earth pressure when back-to-back walls interact with each other. Moreover, for closer BBMSEWs, FHWA design guideline strongly overestimates the maximum tensile force in the reinforcement. The investigation of the quality of backfill material shows that the minor increase in embankment cohesion can lead to significant reductions in both the lateral earth pressure and the maximum tensile force in geosynthetic. When the distance between the two earth walls is close to zero, the connection of reinforcement between back-to-back walls significantly improves the factor of safety.

Beschreibung: Publication date: Available online 28 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Hossein Mola-Abasi, Issa Shooshpasha It is well known that the cemented sand is one of economic and environmental topics in soil stabilization. In this instance, a blend of sand, cement and other materials such as fiber, glass, nanoparticle and zeolite can be commercially available and effectively used in soil stabilization in road construction. However, the influence and effectiveness of zeolite on the properties of cemented sand systems have not been completely explored. In this study, based on an experimental program, the effects of zeolite on the characteristics of cemented sands are investigated. Stabilizing agent includes Portland cement of type II and zeolite. Results show the improvements of unconfined compressive strength (UCS) and failure properties of cemented sand when the cement is replaced by zeolite at an optimum proportion of 30% after 28 days. The rate of strength improvement is approximately between 20% and 78%. The efficiency of using zeolite increases with the increases in cement amount and porosity. Finally, a power function of void-cement ratio and zeolite content is demonstrated to be an appropriate method to assess UCS of zeolite-cemented mixtures.

Beschreibung: Publication date: Available online 28 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Atsushi Sainoki, Hani S. Mitri Fault-slip taking place in underground mines occasionally causes severe damage to mine openings as a result of strong ground motion induced by seismic waves arising from fault-slip. It is indicated from previous studies that intense seismic waves could be generated with the shock unloading of fault surface asperities during fault-slip. This study investigates the shock unloading with numerical simulation. A three-dimensional (3D) numerical model with idealized asperities is constructed with the help of discrete element code 3DEC. The idealization is conducted to particularly focus on simulating the shock unloading that previous numerical models, which replicate asperity degradation and crack development during the shear behavior of a joint surface in previous studies, fail to capture and simulate. With the numerical model, static and dynamic analyses are carried out to simulate unloading of asperities in the course of fault-slip. The results obtained from the dynamic analysis show that gradual stress release takes place around the center of the asperity tip at a rate of 45 MPa/ms for the base case, while an instantaneous stress release greater than 80 MPa occurs near the periphery of the asperity tip when the contact between the upper and lower asperities is lost. The instantaneous stress release becomes more intense in the vicinity of the asperity tip, causing tensile stress more than 20 MPa. It is deduced that the tensile stress could further increase if the numerical model is discretized more densely and analysis is carried out under stress conditions at a great depth. A model parametric study shows that in-situ stress state has a significant influence on the magnitude of the generated tensile stress. The results imply that the rapid stress release generating extremely high tensile stress on the asperity tip can cause intense seismic waves when it occurs at a great depth.

Beschreibung: Publication date: Available online 18 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Morteza Esmaeili, Hamid Khajehei Deep mixed column (DMC) is known as one of the effective methods for stabilizing the natural earth beneath road or railway embankments to control stability and settlements under traffic loads. The load distribution mechanism of embankment overlying on loose subgrades stabilized with DMCs considerably depends on the columns' mechanical and geometrical specifications. The present study uses the laboratory investigation to understand the behavior of embankments lying on loose sandy subgrade in three different conditions: (1) subgrade without reinforcement, (2) subgrade reinforced with DMCs in a triangular pattern and horizontal plan, and (3) subgrade reinforced with DMCs in a square pattern and horizontal plan. For this purpose, by adopting the scale factor of 1:10, a reference embankment with 20 cm height, 250 cm length, and 93% maximum dry density achieved in standard Proctor compaction test was constructed over a 70 cm thick loose sandy bed with the relative density of 50% in a loading chamber, and its load-displacement behavior was evaluated until the failure occurred. In the next two tests, DMCs (with 10 cm diameter, 40 cm length, and 25 cm center-to-center spacing) were placed in groups in two different patterns (square and triangular) in the same sandy bed beneath the embankment and, consequently, the embankments were constructed over the reinforced subgrades and gradually loaded until the failure happened. In all the three tests, the load-displacement behaviors of the embankment and the selected DMCs were instrumented for monitoring purpose. The obtained results implied 64% increase in failure load and 40% decrease in embankment crest settlement when using the square pattern of DMCs compared with those of the reference embankment, while these values were 63% and 12%, respectively, for DMCs in triangular pattern. This confirmed generally better performance of DMCs with a triangular pattern.

Beschreibung: Publication date: Available online 15 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Brian G. Sexton, Bryan A. McCabe, Minna Karstunen, Nallathamby Sivasithamparam The recently developed elasto-viscoplastic Creep-SCLAY1S model has been used in conjunction with PLAXIS 2D to investigate the effectiveness of vibro-replacement in a creep-prone clay. The Creep-SCLAY1S model accounts for anisotropy, bonding, and destructuration, and uses the concept of a constant rate of viscoplastic multiplier to calculate creep strain rate. A comparison of settlement improvement factors with and without creep indicates that ‘total’ settlement improvement factors (primary plus creep) are lower than their ‘primary’ counterparts (primary settlement only). The lowest settlement improvement factors arise for analyses incorporating the effect of bonding and destructuration. Examination of the variations of vertical stress with time and depth has indicated that vertical stress is transferred from the soil to the column as the soil creeps. This results in additional column yielding. In addition, the radial and hoop stresses in the soil are lower for the ‘creep’ case. The reduced radial stresses lead to additional column bulging and hence more settlement, whereas the hoop stress reductions appear to be a secondary effect, caused by additional plastic deformation for the ‘creep’ case.

Beschreibung: Publication date: Available online 27 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Xudong Wang, Qinlin Guo, Shanlong Yang, Dexuan Zhang, Yanwu Wang arthen sites are widely distributed throughout China, and most of them belong to archaeological sites with significant values, which not only directly witness the origin, formation and development of Chinese civilization, but also possess important values for conservation and exhibition. Many researches and practices on their conservation and consolidation have been carried out; however, the consolidation effect is mainly judged by visual observation and expert evaluation. Scientific assessment of conservation and consolidation effects is a challenging issue. Many instruments in other fields cannot be directly applied to the conservation of cultural relics due to their peculiarity. In order to assess the effects of field conservation experiments, this paper tries to understand the consolidation effects at Liangzhu site using nondestructive or micro-damage methods, including thermo-physical parameters testing, infrared thermal imaging, high-density microelectrode resistivity testing, portable microscope observation, and hydrophilic and hydrophobic testing, and thereby explores the practicable methods for evaluating the properties of consolidation materials for earthen sites treatment.

Beschreibung: Publication date: Available online 25 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Hongwei Wang, Yaodong Jiang, Sheng Xue, Lingtao Mao, Zhinan Lin, Daixin Deng, Dengqiang Zhang This paper presents an investigation on the characteristics of overlying strata collapse and mining-induced pressure in fault-influenced zone by employing the physical modeling in consideration of fault structure. The precursory information of fault slip during the underground mining activities is studied as well. Based on the physical modeling, the optimization of roadway support design and the field verification in fault-influenced zone are conducted. Physical modeling results show that, due to the combined effect of mining activities and fault slip, the mining-induced pressure and the extent of damaged rock masses in the fault-influenced zone are greater than those in the uninfluenced zone. The sharp increase and the succeeding stabilization of stress or steady increase in displacement can be identified as the precursory information of fault slip. Considering the larger mining-induced pressure in the fault-influenced zone, the new support design utilizing cables is proposed. The optimization of roadway support design suggests that the cables can be anchored in the stable surrounding rocks and can effectively mobilize the load bearing capacity of the stable surrounding rocks. The field observation indicates that the roadway is in good condition with the optimized roadway support design.

Beschreibung: Publication date: Available online 18 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Aiqing Wu, Jimin Wang, Zhong Zhou, Shuling Huang, Xiuli Ding, Zhihong Dong, Yuting Zhang Based on the analyses of data obtained from the underground powerhouse at Jinping I hydropower station, a comprehensive review of engineering rock mechanics practice in the underground powerhouse is first conducted. The distribution of strata, lithology, and initial geo-stress, the excavation process and corresponding rock mass support measures, the deformation and failure characteristics of the surrounding rock mass, the stress characteristics of anchorage structures in the cavern complex, and numerical simulations of surrounding rock mass stability and anchor support performance are presented. The results indicate that the underground powerhouse of Jinping I hydropower station is characterized by high to extremely high geo-stresses during rock excavation. Excessive surrounding rock mass deformation and high stress of anchorage structures, surrounding rock mass unloading damage, and local cracking failure of surrounding rock masses, etc., are mainly caused by rock mass excavation. Deformations of surrounding rock masses and stresses in anchorage structures here are larger than those found elsewhere: 20% of extensometers in the main powerhouse record more than 50 mm with the maximum at around 250 mm observed in the downstream sidewall of the transformer hall. There are about 25% of the anchor bolts having recorded stresses of more than 200 MPa. Jinping I hydropower plant is the first to have an underground powerhouse construction conducted in host rocks under extremely high geo-stress conditions, with the ratio of rock mass strength to geo-stress of less than 2.0. The results can provide a reference to underground powerhouse construction in similar geological conditions.

Beschreibung: Publication date: Available online 4 August 2016 Source: Advances in Climate Change Research Author(s): Matthew Jenkins, Susan Kaspari, Kang Shi-Chang, Bjorn Grigholm, Paul A. Mayewski Black carbon (BC) deposited on snow and glacier surfaces can reduce albedo and lead to accelerated melt. An ice core recovered from Guoqu glacier on Mt. Geladaindong and analyzed using a Single Particle Soot Photometer (SP2) provides the first long-term (1843‒1982) record of BC from the central Tibetan Plateau. Post 1940 the record is characterized by an increased occurrence of years with above average BC, and the highest BC values of the record. The BC increase in recent decades is likely caused by a combination of increased emissions from regional BC sources, and a reduction in snow accumulation. Guoqu glacier has received no net ice accumulation since the 1980s, and is a potential example of a glacier where an increase in the equilibrium line altitude is exposing buried high impurity layers. That BC concentrations in the uppermost layers of the Geladaindong ice core are not substantially higher relative to deeper in the ice core suggests that some of the BC that must have been deposited on Guoqu glacier via wet or dry deposition between 1983 and 2005 has been removed from the surface of the glacier, potentially via supraglacial or englacial meltwater.

Beschreibung: Publication date: Available online 3 August 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Shengwu Song, Xuemin Feng, Chenggang Liao, Dewen Cai, Zhongxu Liu, Yunhao Yang The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Sadhan Kumar Ghosh India generates nearly 62 million tons of MSW annually that creates huge problems in the environment. Small number of initiatives of waste treatment, e.g., incineration, pyrolysis, bio-refining & biogas plants, composting, recycling and SLFs are available in the country. For the sustainable Solid Waste Management (SWM), an inclusive improvement policy and paradigm shift is necessary. SBM (SBM), flagged off on October 2, 2014, is considered as a paradigm shift in Indian SWM movement. SBM is the country's biggest-ever cleanliness drive costing over 10,600 million USD for 5 years in 4,041 towns in which SWM considered as one of the six components. One of the stated objectives of SBM is to ensure door-to-door garbage collection and proper disposal of municipal solid waste in all the 83,000 wards in urban areas by 2019. Swachh Bharat citizen communities were formed subsequently to generate awareness and citizen participation. Since then, over a period of 12 months, over 335,000 citizens have become part of the various Swachh Bharat citizen communities across more than 100 cities of India. The study reviews the present status and sustainability of the activities undertaken and proposes some improvement scopes in the schemes under the SB mission for effective SWM in India. The study will definitely help in revisiting the scheme periodically for continual improvement.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): A.O. Coker, C.G. Achi, M.K.C. Sridhar, C.J. Donnett Waste generation is an intrinsic part of human existence. Waste materials are usually characterized by their nature, components and quality. Variations in quality, quantity and composition of solid waste can be linked to various factors such as cultural, economic, social and financial status of inhabitants of the particular space being studied. These distinct factors will also determine the best waste management practice to adopt. This paper captures the current institutional solid waste management in a Nigerian Private institution of higher learning. Using key-informant interview and personal field observations, the waste generation rate, pattern and characterization was made. Results showed that between 0.3 and 0.4 kg/capita/day was generated daily by the students in their respective halls of residence, with population ranging from 762 – 848 students in each of the halls. All the solid wastes generated were collected using appropriate waste collection bags and mobile bin positioned at strategic corners of the university premises. The waste materials after collection were segregated into plastics, bottles, nylon and organic materials by scavengers. After these non-bidegradables were sold in the secondary market, an estimated total sum of 639,900 naira (2908.6USD) was realized daily. At this rate a total sum of 230 million Naira (1,045,454.5 USD) is realizable yearly as wealth from waste. It was concluded that if all the organic waste streams from kitchens, cafeteria and animal houses are utilized for bioenergy and organic fertilizer, the wealth to be generated would be phenomenal.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Pawan Kumar Bharti, Bhupesh Sharma, R.K. Singh, A.K. Tyagi Antarctica is the coldest continent on the earth. The Indian Ocean, Pacific Ocean and Atlantic Ocean surround the continent. Antarctic continent covers 10% of the earth surface and has a surface area of nearly 14 million square kilometer. It also has 70% of the world's fresh water resources in the form of ice sheets. Thick ice sheets cover the whole continent (almost 98%). As a result of the environmental conditions, the remaining (2%) fraction without ice cover is basically the barren soil and rocks. Many countries have set up scientific research stations in Antarctica. There are about 65 scientific research stations in summer and 30 research stations in winter, which are currently operating for scientific investigations. India has two permanent scientific research stations in the Antarctica located in Schirmacher Oasis in Central Dronning Maud Land and in Larsemann Hills, East Antarctica. However, the activities due to operation and maintenance of the research station in Antarctica have impacts on the Antarctic environment. Besides, the scientific stations also generate waste materials and a significant part of it is discharged into the Antarctic environment, which may create impacts on the Antarctica. The assessment of waste materials emanating from various sources was carried out. The present paper attempts to highlight the environmental parameters observed during ISEA austral summer at Maitri and Bharti station, East Antarctica.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): A.S. Aremu, Ritesh Vijay Indigenous footpaths have been the major means of passage from origin to destination before the advent of cars and town planning. Over the years, these traditional areas have retained their original attributes with additional walking links to the motorable roads. In this study, footpaths to municipal solid waste bins were modelled in order to locate waste bins within an area in Ilorin, north central Nigeria. A network dataset was built in a standard GIS application (ArcMap 10) from the downloaded satellite image of the study area. The Location-Allocation tool in the Network Analyst window was then used to determine the optimal location of facilities based on cut-off walking distance which defines command area of a waste bin. The result of this analysis could act as a decision support tool for the determination of type, size and removal frequency of each waste bin based on estimates of waste generation from each command area.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Mustapha Bashir Kazaure A survey on solid waste management for sustainable development and public health in Dutse metropolis was conducted. One hundred (100) designed questionnaires were distributed across four major areas within the town which included Yadi, GidaDubu, Dan Masara and Mopol base quarters were twenty five (25) are distributed to each of the four sites. From the result, it was discovered that residence of Danmasara quarters discharge all their waste 100(100%) in government approve sites while Yadi quarters are the lowest in terms of discharging waste in government designated locations 6(24%). Based on flooding, Yadi recorded the highest rate of flooding 21(84%) while Dan masaraquartes recorded the lowest 9(36%). Proper waste discharge was also summarized according to educational status of individual respondents within the affected areas under study. It could be observed that people with secondary education had the highest of (47%) while informal education recorded the lowest (08%) in terms of proper waste discharge respectively. It is concluded that most of places in Dutse metropolis do not access to drainage system as well as government designed areas for waste disposal and hence, it is recommended that government should provide adequate waste disposal sites to each area within Dutse metropolis.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Pinky Chandran, Sandya Narayanan This paper studies the role of Dry Waste Collection Centers (DWCCs) in Municipal Solid Waste Management in Bangalore which were set up following LokAdalat's intervention directing the Municipality to set up these centers to enable ward level recycling. The Karnataka High Court further validated the direction by instructing the municipality to set up necessary infrastructures to facilitate ward level decentralized management of waste for all categories. The DWCC is a hallmark of the triple bottom line of sustainable business operations– people, planet and profit, and modeled on three corner- stones – Social Considerations, Economic Considerations and Environmental Impact. Based on a zero-subsidy model for operations, the DWCCs are envisioned to meet the environmental objective of managing the MSW recyclable waste stream through responsible recycling. They are also expected to be a hub for social inclusion of the informal sector in the process, and ensure economic viability through market driven delivery mechanisms. The paper traces the history of DWCCs and studies the operations of 32 DWCCs which have been in operation for more than a year and operated by the informal sector. In addition, the paper will also analyze the effect of dry waste diverted from landfills at the ward level and will provide recommendations to enhancing performance of these centers.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Subzar Bashir, Subhrangsu Goswami Municipal Solid Waste Management (MSWM) is one of the crucial urban basic services which influence the public health and environment of a town. While hill towns in India are already facing tremendous pressure due to lack of infrastructure, unfavourable climatic condition, difficult terrain, and public apathy towards waste management, Tourism induced challenges further aggravate the issue. Although in case of hill towns, tourism has a profound impact on the economy of the town, it comes with new challenges in terms of waste generation resulting into negative impacts on the sensitive hill environment. It is in this context, an effort has been made in this paper to examine the current issues and challenges in MSWM practice in Pahalgam, a small hill town located in the state of J&K, commonly known as “Mini Switzerland”, with special reference to impact of tourism on overall MSWM of the town. The methodology adopted includes review of case of SWM in other hill towns in India, and the legal and policy aspects at the national level. Primary survey of households and hotels was conducted by using stratified random sampling technique. Data was collected through structured questionnaire containing key information related to the issues and challenges in MSWM with special focus on tourism. Interview of city officials was conducted to capture institutional perspective. The study revealed that, in Pahalgam, tourism sector is the major generator of solid waste, Religious-touristic activities during the peak season. The study also finds crucial issues related to lack of capacity of the local body and the issues related to lack availability of plain land, improper location of waste collection infrastructure due to undulated terrain and inadequate collection capacity. The study also finds very strong correlation between unscientific disposal of MSW and degrading surface water quality and increasing occurrence of water borne diseases in the downstream during the peak tourist season.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Vinay Yadav, Subhankar Karmakar, A.K. Dikshit, Shivkumar Vanjari In India, a substantial fraction (∼0.85) of total expenditure on MSW management is spent on collection of waste. Nevertheless, the average waste collection efficiency is about 70% in Indian urban areas. Waste collection efficiency can be increased by utilising staff and collection vehicles effectively with transfer stations (TSs), though choosing best sites (in an economically optimal manner) for TSs siting is a major task. Also, many parameters (e.g., waste-generation rate, running cost of facilities, transportation cost, revenues etc.) in MSW management system are associated with uncertainties. To study the apportionment of these uncertain input parameters into the results, a comprehensive sensitivity analysis has been performed. Furthermore, the effect of interaction among most sensitive parameters is examined through design of experiment. Also, a facility location two stage stochastic model has been proposed to select the best sites for TSs siting, which is basically a framework of facility location problems involving uncertainty. The developed model is applied on the city of Nashik, Maharashtra, India. The model has 9186 constraints and 8152 variables, which has been written in AMPL (a mathematical programming language). KNITRO 5.2 (nonlinearinterior-point trust region optimizer) have been used to solve the developed model. Sensitivity analysis abduces waste generation as the most sensitive kind of parameter followed by the unit transportation cost of waste from source to TSs. Furthermore, multivariate SA identifies the importance of a facility location framework involving uncertainty.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Hamsa Iyer Mumbai Metropolitan Region (MMR), spread over 4,355sq. km is home to seven municipal corporations. All Municipal Corporations in India are mandated to look into solid waste management in their functional domains under the 74th Constitutional Amendment. At present, all the seven municipal corporations depend upon centralised means of managing waste which is dumped at assigned landfills post collection. Apart from the corporation, there are multiple players who play a crucial role in managing the waste. Much of this is managed by informal sector and now emerging recyclers who are setting up processes for decentralised waste management. This paper explores the scale at which different institutions/communities have taken efforts to successfully manage their waste. Most people are unable to achieve 100% decentralized management due to lack of appropriate channels for managing rejects and sanitary waste. More importantly, it is imperative to understand the failure and limitations of the municipal corporation since they are financially dependent on the centre and state for their functioning. But despite all those constraints, it makes sense to gauge energy and material recovery potentials and correlate to municipal waste management. By means of different examples and a technology provider for bio-medical waste, we are able to make an impact towards creating greener, sustainable communities.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Ajaykumar Soni, Deepak Patil, Kuldeep Argade Solid waste management all over world is looked as major challenge to civil bodies. Pune corporation has taken initiatives to collect, segregate and treat solid waste and system for handling around 1600 MT / day is operative. Composting, biogas and inert waste recycle are present mode of treatment. Praj Industries limited, Pune has taken the activity further to noticeable level and can integrate overall waste management activities so that from biodegradables, biodiesel, bio CNG, fuel ethanol and liquid manure can be safely produced. No waste is left over. Biodegradable solid waste in Pune has potential to generate Biodiesel-18 to 20 MT/ day, Fuel ethanol-7 to 9 M3/ day, BioCNG-10 to 12 MT/ day and in addition 1100 to 1200 M3 liquid manure / day can be produced. These energy rich compounds can generate electricity, run vehicles and maintain solid fertility. One has to look scientifically in the optimization of collection and segregation from the point where waste generates.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): K. Chithra, P.P. Anilkumar, M.A. Naseer According to United Nation's World urbanization prospects Report, urban population in the world is expected to touch 70% of the total population by 2050. Urbanization trend in the world has made residential land-use, a major shareholder amongst urban land uses. This land-use has become the major deciding factor for urban infrastructure development at large. Municipal solid waste management and its related infrastructure provision have become a major concern to many of the urban local self-governments in India. Major objective of this paper, which is based on a doctoral research work on the residential land use impact on urban environment is to examine the relative position of municipal solid waste management sector among the other identified sectors of urban environment and also to evolve a waste management index that can be used to compare urban areas in terms of its waste generation and management perspective. An AHP based expert questionnaire survey of 93 experts across India was conducted to identify the significance of municipal solid waste management sector along with the identified impacted sectors of urban environment due to residential land use activities. A household survey was conducted in 51 wards of Kozhikode Corporation to check the performance of the waste management index generated out of the expert survey. The results of the survey show that the municipal solid waste management sector is the most impacted sector among the urban environment sectors. Waste management index of the surveyed wards revealed that the index is aligning very well with the residential density as well as the residential land-use characteristics of the area under consideration. This index has immense potential to identify the urban areas that require intervention possibly by providing infrastructure for municipal solid waste management. Survey inputs are gathered, compared and composed in this regard and the results are presented and communicated in this paper.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): R.L. Verma, G. Borongan, M. Memon Management of solid waste, including the municipal solid waste (MSW), is a major challenge in urban regions of most part of the world, including Southeast Asia. Due to the lack of effective management programs, regulations, and policies; the waste is causing severe health hazard including several communicable diseases, bad odors, nuisance, and environmental impacts, such as, contamination of water, soil, and air. Most Southeast Asian cities are lacking efficient MSW management programs. Thus, in order to contribute to building a good dataset on MSW for the Southeast Asian region, we quantified solid waste generation and analyzed waste composition for Ho Chi Minh City. Ho Chi Minh City is a major urban region of Viet Nam in Southeast Asia. In Ho Chi Minh City, about 8,175 tons of solid waste was generated per day in 2014, consisting 6,800-7,000 of MSW, with 1.02 kg/capita/day generation of waste. The trend in MSW generation from 1992-2010 showed that 98,338 tons of MSW has been increasing every year. The MSW of Ho Chi Minh City contains 65-90% biodegradable matter. The major portion of MSW was food waste from 1.4 million households, 1,837 schools, and 12,000 hotels and restaurants. The current common practice of solid waste management in Ho Chi Minh City is landfilling. About 86% of the total solid waste was landfilled at two major landfill sites (PhuocHiep and Da Phuoc), and the rest 14% waste was recycled. Paper, plastic, metals, glass were the major waste being recycled with a quantity of 3364, 3794, 1124, and 384 tons/month, respectively. Further to support the MSW planning in Ho Chi Minh City, we analyzed gaps and SWOT (strengths, weakness, opportunities, and threats) and provided recommendations to be incorporated in the action plans for efficient management of solid waste in Ho Chi Minh City.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Giresh Mohan, Ujjawal Kumar Sinha, Meva Lal Solid waste management is fast becoming an insurmountable challenge across urban India, requiring urgent solutions, especially in view of rapid urbanization and inability of local urban authorities to tackle it. Saharanpur, a small city in Uttar Pradesh, represents a microcosm of most large cities and towns in India, grappling with similar challenges. With a decadal population growth of over 19% during 2001-2011, which is higher than the national growth, the city is confronted with the task of managing a rapid growth in solid waste. In order to come up with viable solutions to this problem ITC Limited, in collaboration with Muskan Jyoti Samiti, an NGO, and the local municipal authority, initiated a pilot PPP project on solid waste management in the year 2006. With persistent focus on processing, recycling and user fee, this initiative has been able to surpass the national benchmark of 80% waste recovery set by the Ministry of Urban Development (MoUD). The cost of collection and processing is covered through revenue from user fees and compost sale.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Tapas Kumar Ghatak Issues related to waste management in the context of Indian Cities still requires a path finder as most of the SWM planners and Executers are still in the dark which part of the SWM rule 2002 needs to be addressed in the primary stage. In fact finding it hard to plan and execute it was thought it may be better to change certain part of the rules which is not even 15 years old. A draft rules awaits approval and most of the people are not actually knows what is being changed and why. In fact this part of the facilities has never been considered as part urban infrastructures neither the citizen's opinion was asked in any stage while framing the rules or while even changing it for betterment. The present paper generates Certain issues related to Waste management which have been experienced while being involved in various cities in national and International arena and picks up certain unaddressed issues related to Waste management in Indian Cities. The main aim of this paper is to combine the opinion with a learned group of participants and try to evolve an effective pathway for its management. One of the most prominent factors which is missing in the entire process is the role of Community as a stake holder and their inclusion in the entire process.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Sadhan Kumar Ghosh The waste management is a major issue in most of the developing countries in the globe. India and China are two faster growing economies who also have similar problems to handle huge amount of municipal solid waste (MSW). Moreover, with the population growth and the increasing GDP, the MSW generation rate is increasing proportionately. Both the countries investing a loads of funds in landfill sites, MSW handling and treatment, but still the problem is not resolved. The main hurdle is the awareness of the citizen and poor institutional initiative all through the country, in general. There are a number of good initiatives, of course. This study aims to explore the present situation of the management of MSW and analyse the sustainability of the initiatives to protect the environment and resource utilisation leading to the least amount of landfill in India and China.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): M. Nelles, J. Grünes, G. Morscheck The new German Closed Cycle Management Act is aimed to turn the waste management into a resource management. The realisation that waste can be a useful source of raw materials and energy is not new; metals, glass, and textiles have been collected before and put to new use. The waste management policy, which has been adapted in Germany over the past 20 years, is based on closed cycles and assigns disposal responsibilities to manufacturers and distributors of products. This has made people even more aware of the necessity to separate waste, led to the introduction of new disposal technologies, and increased recycling capacities. Today, 14 per cent of the raw materials used by the German industry are recovered waste. Modern closed cycle management contributes, with a share of approximately 20 per cent, to achieve the German Kyoto targets on the reduction of climate-relevant emissions.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): K. Patchai Murugan, S. Swarnalatha, G. Sekaran Tannery buffing dust (TBD) contains high amount of potential chemicals including Cr (III) besides carcinogenic organic compounds. The Cr (III) present in TBD can be thermodynamically feasible to convert into carcinogenic Cr (VI). The obnoxious gases such as oxides of sulphur, ammonia and other volatile organic compounds are emitted from tannery buffing dust during the thermal decomposition. Pyrolysis of a chromium-tanned buffing dust under controlled O 2 atmosphere has been carried out in a thermal reactor to eliminate the environmental burden of these toxic pollutants. The effect of process variables, such as temperature, pyrolysis time, and heating rate on the pyrolytic product distribution was studied. Flash pyrolysis upto 550°C and slow pyrolysis from 550 to 800°C with applying O 2 at the rate of 1LPM in the temperature range between 700 and 800°C were studied. The pyrolysed tannery buffing dust was characterized by XRD, SEM, FTIR, TGA and CHNS analyzer. The pyrolysed TBD was effectively solidified / stabilized using Portland cement and also bitumen mixture. Unconfined compressive strength of the blocks was in the range of 16-99KN. The leachability of the stabilization of Cr (III) in the solidified matrix was confirmed through XRD.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): Akanksha Kaushal, M.P. Sharma In developing countries, quantities of solid waste generation is increasing day by day and most of which is disposed off through landfilling and open dumping resulting into the release of significant quantities of GHG. CH 4 , the major gas produced by these activities, is known to cause global warming. The paper reports the estimates of CH 4 calculated by using IPCC Default, FOD method and LandGEM model, version 3.02 from Panki open dump site of Kanpur, India. The annual average CH 4 emission rates from Panki open dump site is found as 197.33, 24.27 and 25.14 Gg by IPCC Default method, FOD and LandGEM respectively for the period 2010-2030. The study reveals that IPCC Default method over estimate the result therefore it is not recommended for open dump site. however, LandGEM is recommended over FOD method for open dumps due to the fact that [a] estimates of CH 4 emission is very near to GHG emission by FOD method [b] simplicity in model parameters [c] avoidance of over estimation, if parameters are calculated as per the actual site conditions. So the present study reveals that LandGEM provides better estimation compared to other method and the CH 4 emission rate is found as 25.14 Gg/year for the Panki open dump site, Kanpur. The assessment of methane emission potential reveals the fact that upgrading the open dumps into landfill increases the methane emission rates and their utilization potential and adding the landfill to fill the future needs and utilization of landfill gases.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): R.M. Kurakalva, K.K. Aradhi, K.Y. Mallela, S. Venkatayogi Rapid urbanization and population growth are largely responsible for exponentially increasing rate of solid waste in the urban areas. The proper management and recycling is a major problem of Municipal Corporation which is great concern of human health and environment. The purpose of this study is to assess groundwater contamination in and around of Jawaharnagar Municipal Solid Waste (MSW) dumping site due to heavy metals and its relationship between hydrochemical data. Groundwater samples were collected from the wells located in the vicinity of the dumping site and its surrounds in a watershed. The samples were analyzed for physicochemical properties as well as for major ion concentrations such as Ca 2+ , Mg 2+ , Na + , K + , CO 3 2ˉ , HCO 3 ˉ , Cl ˉ , NO 3 ˉ , F ˉ and SO 4 2ˉ using ion chromatograph. Results suggest the high concentrations of major ions such as Ca 2+ , Mg 2+ , and F − is observed in groundwater indicating differential weathering of minerals present in granite rocks in the study area. A good number of samples are showing higher values for NO 3 ˉ than that of World Health Organization (WHO) drinking water guideline values. This demonstrates the oxidation of ammonia and similar sources from lechates originating from municipal solid waste of the study area. Further, heavy metals such as Cd, Cr, Cu, Fe, Mn, Pb and Zn are analyzed using Inductively Coupled Plasma-Mass Spectrometer. The data revealed elevated concentrations of Arsenic (0.04-0.36 ppb), Cadmium (0.00-0.09 ppb), Chromium (24.0–28.0 ppb), Copper (0.61–2.9 ppb), Iron (11.99-35.26 ppb), Manganese (1.04-107.2 ppb), Lead (0.19-1.32 ppb) and Zinc (1.49 –49.59 ppb). The present study demands proper management of landfill site and municipal solid waste to reduce further groundwater contamination via percolation of toxic substances.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): R.K. Kashyap, Parivesh Chugh, T. Nandakumar Currently, nearly 210 Million Metric Tonnes/Annum of Municipal Solid Waste (MSW) is generated in India and most of it gets disposed in Open and un-scientifically managed Landfills. The typical Indian MSW contains approximately 50% of bio-degradable organic components that starts degrading under anaerobic conditions and generates LandFill Gas (LFG). The LFG mainly contains Methane (40-50%) and CO 2 (50-60%). Methane is a Green House Gas (GHG), and is 25 times more potent than CO 2 in causing Global Warming and is the 2 nd largest anthropogenic source of Methane emissions after coal mining. Thus capturing and destructions of LFG shall lead to mitigation of GHG emissions. In addition, open Landfill sites also pose safety risks like fire hazard, explosion, and asphyxiation etc. apart from health risks. At the current MSW generation rate of 0.575MMT/day in India, the LFG generation potential is around 86.25 MMSCMD of LFG. Presently, LFG from the landfill sites is not being captured leading to fugitive GHG emissions. Further, due to rapid population growth and accompanying urbanisation and lack of new landfill sites, the existing waste handling infrastructure is getting stressed and leading to overflowing and vertical growth of the existing landfills. Thus Indian landfills provide good opportunities for the extraction & utilisation of Methane from LFG. However, there are lot of Issues that need to be overcome for exploitation of LFG in a sustainable manner. GAIL (India) Ltd, a Maharatna company, as a part of its R&D activities has taken up an initiative in this direction and implemented a Pilot project to ascertain the recovery of LFG from an un-scientifically managed open active MSW dumping site at Ghazipur Delhi. The utilization of LFG for energy recovery is being explored. This Paper shares the Challenges faced and Key insights gained during the LFG Project Implementation and its Operation.

Beschreibung: Publication date: 2016 Source: Procedia Environmental Sciences, Volume 35 Author(s): P.K. Amritha, P.P. Anilkumar Uncontrolled dumping of waste on open dumps or landfills has become one of the most common methods of disposing waste. Globally, such dumps/landfills have remained as an anomaly in urban landscapes due to its heterogeneous nature and the environmental degradation it causes. This paper considers open dumps/ landfills as specific example cases upgradable to ‘landscaped landfills’ so that landfills transform to be a more sustainable disposal option. Such an approach can be devised only by knowing the quality and quantity of the waste that are disposed in landfills and the background environmental conditions of a particular region. A landfill dominantly of organic/biodegradable character can become a good source of nutrients in developing the soft elements of landscape. In developing a landscaped landfill, the environmental risks associated such as leachate generation, groundwater contamination, greenhouse gas emission and soil stability are major concerns to be addressed. For a long term use of conventional landfills converted into ‘landscaped landfills’ the principles of environmental remediation techniques like phytoremediation, bioremediation and bio reactor landfills have a pivotal role to play. The research work aims at the disposing organic/biodegradable waste on any land or designated open dumps /landfills and simultaneously using the same land for green productive purpose in a cyclic fashion thereby making it a sustainable waste management strategy. The paper discusses the practical issues in converting a landfill into landscaped landfill by doing an onsite experiment using organic kitchen waste considering parameters like the number of households, their expected production of organic waste and suitable worked out land area for dumping, digesting and assimilating waste. In an attempt to streamline the process of planning landscaped landfills, the paper describes a strategy and methodology to convert landfills into a fitting component of typical urban landscapes through enhancing its environmental significance and visual quality for sustainability.