ALBERT

Description: HCFC-22 (CHClF2, chlorodifluoromethane) is an ozone-depleting substance (ODS) as well as a significant greenhouse gas (GHG). HCFC-22 has been used widely as a refrigerant fluid in cooling and air-conditioning equipment since the 1960s, and it has also served as a traditional substitute for some chlorofluorocarbons (CFCs) controlled under the Montreal Protocol. A low frequency record on tropospheric HCFC-22 since the late 1970s is available from measurements of the Southern Hemisphere Cape Grim Air Archive (CGAA) and a few Northern Hemisphere air samples (mostly from Trinidad Head) using the Advanced Global Atmospheric Gases Experiment (AGAGE) instrumentation and calibrations. Since the 1990s high-frequency, high-precision, in situ HCFC-22 measurements have been collected at these AGAGE stations. Since 1992, the Global Monitoring Division of the National Oceanic and Atmospheric Administration/Earth System Research Laboratory (NOAA/ESRL) has also collected flasks on a weekly basis from remote sites across the globe and analyzed them for a suite of halocarbons including HCFC-22. Additionally, since 2006 flasks have been collected approximately daily at a number of tower sites across the US and analyzed for halocarbons and other gases at NOAA. All results show an increase in the atmospheric mole fractions of HCFC-22, and recent data show a growth rate of approximately 4% per year, resulting in an increase in the background atmospheric mole fraction by a factor of 1.7 from 1995 to 2009. Using data on HCFC-22 consumption submitted to the United Nations Environment Programme (UNEP), as well as existing bottom-up emission estimates, we first create globally-gridded a priori HCFC-22 emissions over the 15 yr since 1995. We then use the three-dimensional chemical transport model, Model for Ozone and Related Chemical Tracers version 4 (MOZART v4), and a Bayesian inverse method to estimate global as well as regional annual emissions. Our inversion indicates that the global HCFC-22 emissions have an increasing trend between 1995 and 2009. We further find a surge in HCFC-22 emissions between 2005 and 2009 from developing countries in Asia – the largest emitting region including China and India. Globally, substantial emissions continue despite production and consumption being phased out in developed countries currently.

Description: We examine the distribution of aerosols and associated optical/radiative properties in the Gangetic-Himalayan region from simultaneous radiometric measurements over the Indo-Gangetic Plains (IGP) and the foothill/southern slopes of the Himalayas during the 2009 pre-monsoon season. Enhanced dust transport extending from the Southwest Asian arid regions into the IGP, results in seasonal mean (April–June) aerosol optical depths of over 0.6 – highest over Southern Asia. The influence of dust loading is greater over the Western IGP as suggested by pronounced coarse mode peak in aerosol size distribution and spectral single scattering albedo (SSA). Transported dust in the IGP, driven by prevailing westerly airmass, is found to be more absorbing (SSA550 nm

Description: Iron dissolution from mineral dusts and soil particles is vital as a source of bioavailable iron in various environmental media. In this work, the dissolution of iron oxide particles trapped in ice was investigated as a new pathway of iron supply. The dissolution experiments were carried out in the absence and presence of various organic complexing ligands under dark condition. In acidic pH conditions (pH 2, 3, and 4), the dissolution of iron oxides was greatly enhanced in the ice phase compared to that in water. The dissolved iron was mainly in the ferric form, which indicates that the dissolution is not a reductive process. The extent of dissolved iron was greatly affected by the kind of organic complexing ligands and the surface area of iron oxides. The iron dissolution was most pronounced with high surface area iron oxides and in the presence of strong iron binding ligands. The enhanced dissolution of iron oxides in ice is mainly ascribed to the "freeze concentration effect", which concentrates iron oxide particles, organic ligands, and protons in the liquid like ice grain boundary region and accelerates the dissolution of iron oxides. The ice-enhanced dissolution effect gradually decreased when decreasing the freezing temperature from −10 to −196 °C, which implies that the presence and formation of the liquid-like ice grain boundary region play a critical role. The proposed phenomenon of enhanced dissolution of iron oxides in ice may provide a new pathway of bioavailable iron production. The frozen atmospheric ice with iron-containing dust particles in the upper atmosphere thaws upon descending and may provide bioavailable iron upon deposition onto the ocean surface.

Description: The diurnal pattern of the vertical distribution of biogenic pollen in the lower troposphere was investigated by LIDAR. Meteorological data were taken at the ground. Pollen concentrations were measured at the surface using a Burkard 7-day-recording volumetric spore sampler. Aerosol extinction coefficients and depolarization ratios at 532 nm were obtained from LIDAR measurements in spring (4 May–2 June) 2009 in Gwangju, South Korea. Linear volume depolarization ratios varied between 0.08 and 0.14 and were observed only during daytime (09:00–17:00 local time (LT)) during days of high pollen concentration (4 to 9 May). Daily average pollen concentrations ranged 1000–2500 cm−3 in the same period. The temporal evolution of the vertical distribution of the linear volume depolarization ratio showed a specific diurnal pattern. Linear volume depolarization ratios of more than 0.06, were measured near the surface in the morning. High depolarization ratios were detected up to 2 km aboveground between 12:00 and 14:00 LT, whereas high depolarization ratios were observed only close to the surface after 17:00 LT. Low values of depolarization ratios (≤0.05) were detected after 18:00 LT until the next morning. During the measurement period, the daily variations of the high depolarization ratios close to the surface showed correlation to number concentration measurements of pollen. This finding suggests that high depolarization ratios could be attributed to enhanced pollen concentrations. The diurnal characteristics of the high values of depolarization ratios are thought to be closely associated with turbulent transport. Diurnal and vertical characteristics of pollen, if measured continuously, could be used to improve the accuracy of pollen-forecasting models via data assimilation studies.

Description: We present atmospheric sulfur hexafluoride (SF6) mole fractions and emissions estimates from the 1970s to 2008. Measurements were made of archived air samples starting from 1973 in the Northern Hemisphere and from 1978 in the Southern Hemisphere, using the Advanced Global Atmospheric Gases Experiment (AGAGE) gas chromatographic-mass spectrometric (GC-MS) systems. These measurements were combined with modern high-frequency GC-MS and GC-electron capture detection (ECD) data from AGAGE monitoring sites, to produce a unique 35-year atmospheric record of this potent greenhouse gas. Atmospheric mole fractions were found to have increased by more than an order of magnitude between 1973 and 2008. The 2008 growth rate was the highest recorded, at 0.29 ± 0.02 pmolmol−1 yr−1. A three-dimensional chemical transport model and a minimum variance Bayesian inverse method was used to estimate annual emission rates using the measurements, with a priori estimates from the Emissions Database for Global Atmospheric Research (EDGAR, version 4). Consistent with the mole fraction growth rate maximum, global emissions during 2008 were also the highest in the 1973–2008 period, reaching 7.4 ± 0.6 Gg yr−1 (1-σ uncertainties) and surpassing the previous maximum in 1995. The 2008 values follow an increase in emissions of 48 ± 20% since 2001. A second global inversion which also incorporated National Oceanic and Atmospheric Administration (NOAA) flask measurements and in situ monitoring site data agreed well with the emissions derived using AGAGE measurements alone. By estimating continent-scale emissions using all available AGAGE and NOAA surface measurements covering the period 2004–2008, with no pollution filtering, we find that it is likely that much of the global emissions rise during this five-year period originated primarily from Asian developing countries that do not report detailed, annual emissions to the United Nations Framework Convention on Climate Change (UNFCCC). We also find it likely that SF6 emissions reported to the UNFCCC were underestimated between at least 2004 and 2005.

Description: HCFC-22 (CHClF_2, chlorodifluoromethane) is an ozone-depleting substance (ODS) as well as a significant greenhouse gas (GHG). HCFC-22 has been used widely as a refrigerant fluid in cooling and air-conditioning equipment since the 1960s, and it has also served as a traditional substitute for some chlorofluorocarbons (CFCs) controlled under the Montreal Protocol. A low frequency record on tropospheric HCFC-22 since the late 1970s is available from measurements of the Southern Hemisphere Cape Grim Air Archive (CGAA) and a few Northern Hemisphere air samples (mostly from Trinidad Head) using the Advanced Global Atmospheric Gases Experiment (AGAGE) instrumentation and calibrations. Since the 1990s high-frequency, high-precision, in situ HCFC-22 measurements have been collected at these AGAGE stations. Since 1992, the Global Monitoring Division of the National Oceanic and Atmospheric Administration/Earth System Research Laboratory (NOAA/ESRL) has also collected flasks on a weekly basis from remote sites across the globe and analyzed them for a suite of halocarbons including HCFC-22. Additionally, since 2006 flasks have been collected approximately daily at a number of tower sites across the US and analyzed for halocarbons and other gases at NOAA. All results show an increase in the atmospheric mole fractions of HCFC-22, and recent data show a growth rate of approximately 4% per year, resulting in an increase in the background atmospheric mole fraction by a factor of 1.7 from 1995 to 2009. Using data on HCFC-22 consumption submitted to the United Nations Environment Programme (UNEP), as well as an existing bottom-up emissions estimate, we first create globally-gridded a priori HCFC-22 emissions over the 15 yr since 1995. We then use the three-dimensional chemical transport model, Model for Ozone and Related Chemical Tracers version 4 (MOZART v4) and a Bayesian inverse method to estimate global as well as regional annual emissions. Our inversion indicates that the global HCFC-22 emissions have an increasing trend between 1995 and 2009. We further find a surge in HCFC-22 emissions in 2009 from developing countries in Asia – the largest emitting region including China and India. Globally, substantial emissions continue despite current phase-out of production and consumption in developed countries.

Description: The diurnal patterns in pollen vertical distributions in the lower troposphere were investigated by the LIDAR remote sensing technique. Meteorological and pollen concentration data was measured at the surface using a Burkard 7 day recording volumetric spore sampler. An aerosol extinction coefficient and depolarization ratio of 532 nm was obtained from LIDAR measurements in spring (4 May–2 June) 2009 in Gwagnju, Korea. Depolarization ratios from 0.08 to 0.14 were observed only in daytime (09:00–17:00 local time (LT)) during high pollen concentration days from 4 to 9 May. Vertical distributions in the depolarization ratio with time showed a specific diurnal pattern. Depolarization ratios, which varied from 0.08 to 0.14, were measured near the surface in the morning. High depolarization ratios were detected even up to 2.0 km between 12:00 and 14:00 LT but subsequently were observed only close to the surface after 17:00 LT. Low values of depolarization ratios (≤ 0.05) were detected after 18:00 LT until next morning. During the measurement period, the daily variations in the high depolarization ratios close to the surface showed good agreement with those in surface pollen concentrations, which implies that high depolarization ratios can be attributed to high pollen concentrations. The diurnal characteristics in high values of depolarization ratios were closely associated with turbulent transport, which can be caused by increasing temperature and wind speed and decreasing relative humidity. Continuously measured diurnal and vertical characteristics of pollen data can be further used to enhance the accuracy of the pollen-forecasting model via data assimilation studies.

Description: Little is known about how marine fishes respond to the reduced pH condition caused by the increased CO2 in the atmosphere. We investigated the effects of CO2 concentration on the growth of olive flounder (Paralichthys olivaceus) larvae. Newly hatched larvae were reared in three different concentrations of CO2 (574, 988 and 1297 μatm CO2) in temperature-controlled water tanks until metamorphosis (4 weeks). Body lengths, weights, and the concentration of some chemical elements in larval tissue were measured at the completion of each experiment, and experiment was repeated three times in May, June, and July 2011. Results indicated that body length and weight of flounder larvae were significantly increased with increasing CO2 concentration (P 〈 0.05). Daily growth rates of flounder larvae were higher (0.391 mm) from the high CO2 concentration (1297 μatm) than those (0.361 mm and 0.360 mm) from the lower ones (988 and 574 μatm).The measurement on some chemical elements (Ca, Fe, Cu, Zn and Sr) in fish tissue also revealed the increasing tendency of element concentration with increasing CO2 in seawater, although statistical significance cannot be tested due to the single measurement. It suggests that there are enrichment processes of these cations in larval tissue in the low pH condition.

Description: The Ulleung Basin (UB), located in the southwestern part of the East/Japan Sea (EJS), is considered having an unusually high productivity for a~deep basin. Recently changes have been reported in physical, chemical, and in biological properties. Here we measured the primary and new productivities in the UB using a 13C-15N dual isotope tracer technique. Measurements took place every month for the first time throughout a year for a~better estimate of the annual primary production in the EJS. Temporal variations of temperature, salinity and density (σt) in the study area were highly seasonal as expected for an ocean in the temperate zone. Nutrient distributions reflected these seasonal fluctuations in the vertical structure of the water column. Diatoms were in general the most dominant phytoplankton ranging from 15.5 to 82.2% with an average of 42.0% (S.D. = ± 9.9%). Based on those average daily productivities from our monthly measurements, the annual primary, new, and regenerated production in the UB were 273.0 g C m−2 yr−1, 62.6 g N m−2 yr−1, and 48.7 g N m−2 yr−1, respectively. Our estimated high f-ratio (0.59) in the UB, indicated that the predominant nitrogen source for primary production was nitrate. This is comparable with the nitrogen source in a productive coastal-upwelling region. New carbon production by phytoplankton is estimated as 212.8 g C m−2 yr−1 (S.D. = ± 9.7 g C m−2 yr−1) which indicates that a large portion (78%) of total annual primary production might potentially be exported from the diatom-dominated euphotic zone to a deeper zone in the UB. Further intense integrated field observations will be necessary to improve our understanding of the current marine ecosystem in the UB as an important biological production area in the EJS.