ALBERT

Description: This document outlines the main communication objectives, messages, audiences, and tools of the EuroSea project

Description: The Q10 temperature coefficient, which is widely used in scientific literature, is a measure of the temperature sensitivity of chemical reaction rates or biological processes. However, the conclusions drawn from applying this coefficient to experimental data obtained from biological processes are not universal. In many biological processes, Q10 values are often discordant with the results predicted by the Arrhenius law. The hypothesis tested in the present study is that this problem arises mainly from the fact that the Q10 coefficient is defined by the ratio between rates described by exponential laws instead of power laws. Considering this hypothesis and the need to review the mathematical laws and models currently used to describe rates and Q10 coefficients, we propose a model beyond the usual Arrhenius theory or exponential decay law herein. The proposed mathematical model is based on the theory of deformed exponential functions, with the ordinary Q10 model representing the conventional exponential function. Therefore, all results following the standard model remain valid. Moreover, we include a Q10 free open-source code, written in Python, and compatible with Windows, Linux and macOS platforms. The validation of the proposed model and confirmation of the given hypothesis were performed based on the following temperature-dependent biological processes: soil organic carbon (SOC) decomposition (which is essential to forecast the impact of climate change on terrestrial ecosystems); the metabolism of Arctic zooplankton; physiological processes of the respiratory and cardiovascular systems; rate of oxygen consumption in mitochondria of the eurythermal killifish Fundulus heteroclitus, and leaf respiration.

Description: The results of ice and hydrological studies of the shallow Bay of Braganzavågen (Van Mayen Fjord Bay, West Spitsbergen Island) in March 2016 and 2018, supplemented with model calculations using a thermodynamic model, are presented. The model uses both known methods of localizing the phase transition region-the classical (frontal) for fast ice and in an extended area (two-phase zone) for bottom sediments. For real atmospheric conditions of winter 2015-2016, the new qualitative features of the process of ice formation in the adjacent layers of sea water and bottom soil are revealed. However, due to insufficient knowledge of the heat and mass transfer properties of bottom sediments, the question of quantitative estimates of the process remains open and can be clarified in special field experiments.

Description: Since 2010, the Soil Moisture and Ocean Salinity (SMOS) satellite mission monitors the earth emission at L-Band. It provides the longest time series of Sea Surface Salinity (SSS) from space over the global ocean. However, the SSS retrieval at high latitudes is a challenge because of the low sensitivity L-Band radiometric measurements to SSS in cold waters and to the contamination of SMOS measurements by the vicinity of continents, of sea ice and of Radio Frequency Interferences. In this paper, we assess the quality of weekly SSS fields derived from swath-ordered instantaneous SMOS SSS (so called Level 2) distributed by the European Space Agency. These products are filtered according to new criteria. We use the pseudo-dielectric constant retrieved from SMOS brightness temperatures to filter SSS pixels polluted by sea ice. We identify that the dielectric constant model and the sea surface temperature auxiliary parameter used as prior information in the SMOS SSS retrieval induce significant systematic errors at low temperatures. We propose a novel empirical correction to mitigate those sources of errors at high latitudes. Comparisons with in-situ measurements ranging from 1 to 11 m depths spotlight huge vertical stratification in fresh regions. This emphasizes the need to consider in-situ salinity as close as possible to the sea surface when validating L-band radiometric SSS which are representative of the first top centimeter. SSS Standard deviation of differences (STDD) between weekly SMOS SSS and in-situ near surface salinity significantly decrease after applying the SSS correction, from 1.46 pss to 1.28 pss. The correlation between new SMOS SSS and in-situ near surface salinity reaches 0.94. SMOS estimates better capture SSS variability in the Arctic Ocean in comparison to TOPAZ reanalysis (STDD between TOPAZ and in-situ SSS = 1.86 pss), particularly in river plumes with very large SSS spatial gradients.

Description: The current geochronological state of the art for applying the radiocarbon (14C) method to deep-sea sediment archives lacks key information on sediment bioturbation. Here, we apply a sediment accumulation model that simulates the sedimentation and bioturbation of millions of foraminifera, whereby realistic 14C activities (i.e. from a 14C calibration curve) are assigned to each single foraminifera based on its simulation time step. We find that the normal distribution of 14C age typically used to represent discrete-depth sediment intervals (based on the reported laboratory 14C age and measurement error) is unlikely to be a faithful reflection of the actual 14C age distribution for a specific depth interval. We also find that this deviation from the actual 14C age distribution is greatly amplified during the calibration process. Specifically, we find a systematic underestimation of total geochronological error in many cases (by up to thousands of years), as well as the generation of age–depth artefacts in downcore calibrated median age. Even in the case of “perfect” simulated sediment archive scenarios, whereby sediment accumulation rate (SAR), bioturbation depth, reservoir age and species abundance are all kept constant, the 14C measurement and calibration processes generate temporally dynamic median age–depth artefacts on the order of hundreds of years – whereby even high SAR scenarios (40 and 60 cm kyr−1) are susceptible. Such age–depth artefacts can be especially pronounced during periods corresponding to dynamic changes in the Earth's Δ14C history, when single foraminifera of varying 14C activity can be incorporated into single discrete-depth sediment intervals. For certain lower-SAR scenarios, we find that downcore discrete-depth true median age can systematically fall outside the calibrated age range predicted by the 14C measurement and calibration processes, thus leading to systematically inaccurate age estimations. In short, our findings suggest the possibility of 14C-derived age–depth artefacts in the literature. Furthermore, since such age–depth artefacts are likely to coincide with large-scale changes in global Δ14C, which themselves can coincide with large-scale changes in global climate (such as the last deglaciation), 14C-derived age–depth artefacts may have been previously incorrectly attributed to changes in SAR coinciding with global climate. Our study highlights the need for the development of improved deep-sea sediment 14C calibration techniques that include an a priori representation of bioturbation for multi-specimen samples.

Description: It is a good method to utilize the grain size distribution curves and cumulative frequency curves of marine or river sediments to estimate the hydrodynamic conditions, transportation processes and sedimentary environment. However, researchers can only rely on Excel or Grapher to plot the curves one by one at the present day. The manual plotting procedures are complicated, and calculating the truncation points is time-consuming. To solve the aforementioned problems, we have developed a software tool to plot cumulative frequency curves and calculate the values of truncation points automatically. The software has the ability to plot curves of hundreds of samples accurately and rapidly, promoting researchers to analyze transport mechanisms and hydrodynamic environments. And it is convenient to apply the software to compare the processes of transportation and deposition between different samples.

Description: The exhumation of peridotite rocks in oceanic transform zones passes by the rheological transition between the ductile and brittle deformation until the complete emplacement in the oceanic lithosphere. The São Pedro and São Paulo Archipelago (SPSPA), in the Equatorial Atlantic, records the deformational products of ductile, brittle and the rocks/fluid interaction generating specific structures in each domain. The deformational stages are related to the transpressional and transtensional geodynamics of São Paulo Transform Fault. Firstly, during transpression, exhumation occurs associated with the ductile domain causing intense mylonitization in temperatures between ~700° and 800 °C, defined by olivine and orthopyroxene recrystallization. The interaction with fluids initially originated from the mantle generates amphibole and oxide-rich layers marking the passage to a semi-brittle deformation. The continuation of peridotite exhumation, associated with an NW-SE shortening and transpressional led to a higher availability of hydrothermal fluids. As a consequence, four serpentinization episodes are recorded, which are associated with semi-brittle to brittle transition under temperatures between 300° and 400 °C. Finally, the complete exhumation and establishment of brittle mechanisms led to carbonatation phase near the surface, with temperatures ranging from 300° to 150 °C. The active NW-SE tectonic stress generated E-W strike-slip faults that were filled by carbonates recording the final exhumation stage.

Description: The infaunal living clypeasteroid echinoid genus Echinocyamus is considered a model organism for various ecological and paleontological studies since its distribution ranges from the polar regions to the tropics, and from shallow-marine settings to the deep-sea. Deep-sea analyses of this genus are rare, but imperative for the understanding and function of these important ecosystems. During the 2012 Southern Surveyor expedition, 35 seamounts off the east coast of Australia were dredged in depths greater than 800 m. Of these, six dredges contained a total of 18 deep-sea Echinocyamus tests. The tests have been analyzed for taphonomic alterations including abrasion patterns, macro-borings, micro-borings, depressions on the test, test staining, test filling, encrustation, and fragmentation. Findings are interpreted in the context of the deep-sea setting and are compared to Echinocyamus samples from shallow-water environments. Results show that abrasion in deep-sea environments is generally high, especially in ambulacral and genital pores indicating that tests can persist for a long time on the seafloor. This contrasts with shallow-water Echinocyamus that show lower abrasion due to early test destruction. Macro-borings are present as single or paired holes with straight vertical profiles resembling Lithophaga borings. Micro-borings are abundant and most likely the result of sponge or fungal activity. Depressions on the tests, such as scars or pits, are likely the result of trauma or malformation during ontogeny. Test staining is common, but variable, and is associated with FE/Mn oxidation and authigenic clays based on elemental analyses. Test filling occurs as loose or lithified sediment. Encrustation is present in the form of rudimentary crusts and biofilms. No macro-organisms were found on the tests. Biofilm composition differs from shallow-water environments in that organisms captured in the biofilm reflect aphotic conditions or sedimentation of particles from higher in the water column (e.g., coccoliths). Fragmentation is restricted to the apical system and pore regions. Results of this first comparative study on deep-sea Echinocyamus from Australian seamounts show that the minute tests can survive for a long time in these settings and undergo environmental specific taphonomic processes reflected in various taphonomic alterations.

Description: The present state of constantly increasing plastic pollution is the major concern of scientific researchers. The conventional techniques applied (i.e., burning and landfilling) to get plastic degraded from the environment are inadequate due to harmful byproducts and limited to its recycling. In this review, we have recapitulated recent biotechnological approaches, including synthetic microbial consortia, systems biology tools, and genetic engineering techniques which can pave the path towards the plastic bioremediation and degradation. Moreover, potential plastic degrader microbes and their degradation pathways are also summarized. Lastly, this review focuses on enhancing the understanding of the degradation ability of microorganisms using contemporary biotechnological tools.

Description: This paper describes the characteristics of atmospheric surface layer and heat balance components of snow-ice cover during drift of RV "Akademik Treshnikov" to the north of the archipelagos Franz Josef Land and Svalbard, in the area 80 - 82N, 30 - 45E, in comparison with observations at drifting station North Pole-35", worked in the same area in April 2008, and "Ice Base Cape Baranova" in April 2019. Characteristics of atmospheric surface layer and the energy exchange processes during the drift of the expedition"Transarctica-2019" were significantly affected by the presence of clouds and the state of the ice cover. The influence of these factors led to a decrease in the radiative cooling of the surface, the formation of a warmer and wetter ABL and to a weakening of the turbulent exchange between the atmosphere and the snow-ice cover. Comparison of energy exchange characteristics, calculated for the Bolshevik Island (79° N) and for expedition "Transarctica 2019" area shows good agreement between the monthly averaged values and trends in heat fluxes, despite the fact that in the first case the underlying surface was sea ice cover, and in the second it was the land surface.

Description: Atmospheric deposition of aerosols to the ocean provides an important pathway for the supply of vital micronutrients, including trace metals. These trace metals are essential for phytoplankton growth, and therefore their delivery to marine ecosystems can strongly influence the ocean carbon cycle. The solubility of trace metals in aerosols is a key parameter to better constrain their potential impact on phytoplankton growth. To date, a wide range of experimental approaches and nomenclature have been used to define aerosol trace metal solubility, making data comparison between studies difficult. Here we investigate and discuss several laboratory leaching protocols to determine the solubility of key trace metals in aerosol samples, namely iron, cobalt, manganese, copper, lead, vanadium, titanium and aluminium. Commonly used techniques and tools are also considered such as enrichment factor calculations and air mass back-trajectory projections and recommendations are given for aerosol field sampling, laboratory processing (including leaching and digestion) and analytical measurements. Finally, a simple 3-step leaching protocol combining commonly used protocols is proposed to operationally define trace metal solubility in aerosols. The need for standard guidelines and protocols to study the biogeochemical impact of atmospheric trace metal deposition to the ocean has been increasingly emphasised by both the atmospheric and oceanographic communities. This lack of standardisation currently limits our understanding and ability to predict ocean and climate interactions under changing environmental conditions.

Description: Dissemination of project’s results and engagement with stakeholders towards a sustained results’ exploitation are intrinsically evolving. The vision of the project’s dissemination at the start of it should evolve as the activities progress. This plan presents an update on the EuroSea dissemination plans as seen a year after the kick-off.

Description: Highlights • Regional brain iron concentrations are heterogenous. • Regional distribution of iron is most consistent with ferritin mRNA expression. • SEC-ICP-MS reveals the protein masses that cytosolic iron is associated with. • More than 50 % of cytosolic iron is associated with ferritin. Iron is essential for brain development and health where its redox properties are used for a number of neurological processes. However, iron is also a major driver of oxidative stress if not properly controlled. Brain iron distribution is highly compartmentalised and regulated by a number of proteins and small biomolecules. Here, we examine heterogeneity in regional iron levels in 10 anatomical structures from seven post-mortem human brains with no apparent neuropathology. Putamen contained the highest levels, and most case-to-case variability, of iron compared with the other regions examined. Partitioning of iron between cytosolic and membrane-bound iron was generally consistent in each region, with a slightly higher proportion (55 %) in the ‘insoluble’ phase. We expand on this using the Allen Human Brain Atlas to examine patterns between iron levels and transcriptomic expression of iron regulatory proteins and using quantitative size exclusion chromatography-inductively coupled plasma-mass spectrometry to assess regional differences in the molecular masses to which cytosolic iron predominantly binds. Approximately 60 % was associated with ferritin, equating to approximately 25 % of total tissue iron essentially in storage. This study is the first of its kind in human brain tissue, providing a valuable resource and new insight for iron biologists and neuroscientists, alike.

Description: The aim of this study was to investigate the syntrophic methanogenesis from the perspective of energy transfer and competition. Effects of redox materials and redox potential on direct interspecies electron transfer (DIET) were examined through thermodynamic analysis based on the energy distribution principle. Types of redox materials could affect the efficiency of DIET via changing the total energy supply of the syntrophic methanogenesis. Decreasing system redox potential could facilitate DIET through increasing the total available energy. The competition between hydrogenotrophic methanogens and DIET methanogens might be the reason for the low proportion of the DIET pathway in the syntrophic methanogenesis. A facilitation mechanism of DIET was proposed based on the energy distribution. Providing sufficient electrons, inhibiting hydrogenotrophic methanogens and adding more competitive redox couples to avoid hydrogen generation might be beneficial for the facilitation of DIET.

Description: Marine macroalgae, seaweeds, are exceptionally prolific producers of halogenated natural products. Biosynthesis of halogenated molecules in seaweeds is inextricably linked to reactive oxygen species (ROS) signaling as hydrogen peroxide serves as a substrate for haloperoxidase enzymes that participate in the construction these halogenated molecules. Here, using red macroalga Asparagopsis taxiformis, a prolific producer of the ozone depleting molecule bromoform, we provide the discovery and biochemical characterization of a ROS-producing NAD(P)H oxidase from seaweeds. This discovery was enabled by our sequencing of Asparagopsis genomes, in which we find the gene encoding the ROS-producing enzyme to be clustered with genes encoding bromoform-producing haloperoxidases. Biochemical reconstitution of haloperoxidase activities establishes that fatty acid biosynthesis can provide viable hydrocarbon substrates for bromoform production. The ROS production haloperoxidase enzymology that we describe here advances seaweed biology and biochemistry by providing the molecular basis for decades worth of physiological observations in ROS and halogenated natural product biosyntheses.

Description: Siderophores are natural products which have attracted interest due to their ability to bind metal ions with high affinities. This review considers the complex formation of these natural chelators with all kinds of different metal and metalloid ions and links their chelating properties to potential biotechnological applications and towards environmental context.

Description: Report on assessment of the EuroSea observational (and thematic) networks coordination This Deliverable serves to present the initial situation, in terms of coordination, of the observation and thematic networks in EuroSea represented in work package 3 (WP3). The networks include the networks represented in EuroGOOS and additional ones. The study is based on a comprehensive questionnaire that was answered by all EuroSea WP3 tasks. In addition, information from the Global Observing Networks of GOOS was considered. An important basis for the questionnaire was the list of "Network Attributes, Commitment and Benefits -What it means to be an OPA network" which was compiled by the Observation coordination group (OCG) of GOOS. This deliverable is linked to the deliverable D3.10 that will repeat the assessment at the end of the EuroSea project to assess the evolution of the coordination over the period of the EuroSea project. The present study shows that the observation and thematic networks in EuroSea all have highly developed coordination mechanism elements, except for task 3.7 - ASV, which represents a new network to be established. Given the spectrum of coordination themes and envisioned targets significant heterogeneity across the networks is also evident. The coordination of ship-based observations is not fully represented in EuroSea (and thus in EuroGOOS) and ideally this task should have been divided into research vessels and commercial vessels (container ships, ferries) but as it stands currently is dominated by one technology only (Ferrybox). This reflects the situation in EuroGOOS. For the thematic networks it is interesting to note that the observatories that are operated in task 3.8 (Augmented observatories) are not represented in the observational networks (task 3.1-3.7). The assessment presented in this deliverable has its focus on the status quo. It does not question or analyze the necessity for individuals, institutions and countries to be represented in a network - “Why should individuals, institutions or countries feel a need or a motivation to engage with the networks?”. It seems logical that networks are only founded, maintained and developed when individuals see an advantage in their involvement in a network – for themselves, their institution or a country. The "characteristics" of the apparent advantage of contributing to a network is likely of central importance. For example, if the advantage is only that there are no disadvantages (e.g. fines), a further development and improvement of the network is questionable. This important investigation of the motivation of individuals will be part of final assessment prepared in D3.10.

Description: This report presents the work plan of the Task 2.3: Observing System Simulation Experiments: impact of multi-platform observations for the validation of satellite observations

Description: Highlights • NH4NO3, Tris-HCl, and NH4CH3COO are optimal buffers for use in SEC-ICP-MS metalloprotein analyses. • Optimal range of buffer concentration is 50–200 mM in SEC-ICP-MS. • 100 mM concentration reduces both protein column interactions and ICP-MS maintenance. • Dextran-based columns are best suited for the analysis of apo-copper proteins. The correct identification of the metalloproteins present in human tissues and fluids is essential to our understanding of the cellular mechanisms underpinning a host of health disorders. Separation and analysis of biological samples are typically done via size exclusion chromatography hyphenated with inductively coupled plasma-mass spectrometry (SEC-ICP-MS). Although this technique can be extremely effective in identification of potential metalloproteins, the choice of mobile phase may have a marked effect on results, results by adversely affecting metal-protein bonds of the metalloproteins of interest. To assess the choice of mobile phase on SEC-ICP-MS resolution and the resulting metalloproteome pattern, we analysed several different sample types (brain homogenate; Cu/Zn-superoxide dismutase (SOD1); a molecular weight standard mix containing ferritin (Ft), ceruloplasmin (Cp), cytochrome c (CytC), vitamin B12 (B12) and thyroglobulin (Tg) using six different mobile phase conditions (200 mM, pH 7.5 solutions of ammonium salts nitrate, acetate, and sulfate; HEPES, MOPS and Tris-HCl). Our findings suggest that ammonium nitrate, ammonium acetate and Tris-HCl are optimal choices for the mobile phase, with the specific choice being dependent on both the number of samples and method of detection that is hyphenated with separation. Furthermore, we found that MOPS, HEPES and ammonium sulfate mobile phases all caused significant changes to peak resolution, retention time and overall profile shape. MOPS and HEPES, in particular, produced additional Fe peaks that were not detected with any of the other mobile phases that were investigated. As well as this, MOPS and HEPES both caused significant concentration dependent matrix suppression of the internal standard.

Description: Fusarium oxysporum is a destructive root-infecting plant pathogen that causes significant yield losses in many economically important crop species. Hence, a deeper understanding of pathogen infection strategies is needed. With liquid chromatography-tandem mass spectrometry and gas chromatography-time of flight mass spectrometry platforms, we analyzed the metabolic changes in a time-course experiment with Arabidopsis accessions either resistant (Col-0) or susceptible (Ler-0) to isolates of Fusarium oxysporum forma specialis matthioli infection. We showed a concurrent effect of Fusarium-derived polyols and the mycotoxin beauvericin in the suppression of the immune response of susceptible hosts. A significant increase in oxidized glutathione in the resistant host was probably associated with effective reactive oxygen species-mediated resistance responses. Through a combination of targeted and untargeted metabolomics, we demonstrated the concurrent action of several Arabidopsis defense systems as well as the concurrent action of several virulence systems in the fungal attack of susceptible Arabidopsis.

Description: Symbiotic relationships range from parasitic to mutualistic, yet all endosymbionts face similar challenges, including evasion of host immunity. Many symbiotic organisms have evolved similar mechanisms to face these challenges, including manipulation of the host's transforming growth factor-beta (TGFβ) pathway. Here we investigate the TGFβ pathway in scelaractinian corals which are dependent on symbioses with dinoflagellates from the family Symbiodiniaceae. Using the Caribbean coral, Orbicella faveolata, we explore the effects of enhancement and inhibition of the TGFβ pathway on host gene expression. Following transcriptomic analyses, we demonstrated limited effects of pathway manipulation in absence of immune stimulation. However, manipulation of the TGFβ pathway significantly affects the subsequent ability of host corals to mount an immune response. Enhancement of the TGFβ pathway eliminates transcriptomic signatures of host coral immune response, while inhibition of the pathway maintains the response. This is, to our knowledge, the first evidence of an immunomodulatory role for TGFβ in a scelaractinian coral. These findings suggest variation in TGFβ signaling may have implications in the face of increasing disease prevelance. Our results suggest that the TGFβ pathway can modulate tradeoffs between symbiosis and immunity. Further study of links between symbiosis, TGFβ, and immunity is needed to better understand the ecological implications of these findings.

Description: Highlights • Microplastics act as anthropogenic vectors of trace metals in freshwaters. • Adsorption capacity of microplastics is enhanced by biofilms but is not strong as natural substrates. • Biofilms alter the adsorption kinetics and mechanisms of trace metals onto microplastics. • Microplastics enhance exchange rates of trace metals between water and solid materials. • Anthropogenic substrate is necessary in evaluation of migration and fate of trace metals. Microplastics (MPs) are ubiquitous in freshwater environments, and represent an emerging anthropogenic vector for contaminants, such as trace metals. In this study, virgin expanded polystyrene (PS) particles were placed in a eutrophic urban lake and a reservoir serving as the resource of domestic water for 4 weeks, to develop biofilms on the surface. For comparison, natural adsorbents in the form of suspended particles and surficial sediment were also sampled from these waterbodies. The trace metal adsorption properties of anthropogenic (virgin and biofilm covered microplastics) and natural substrates were investigated and compared via batch adsorption experiments. The adsorption isotherms fitted the Langmuir model, revealed that biofilms could enhance the trace metal adsorption capacity of MPs. However, natural substrates still had a greater adsorption capacity. Biofilms also alter the adsorption kinetics of trace metals onto MPs. The process of adsorption onto virgin MPs was dominated by intraparticle diffusion, whereas film diffusion governed adsorption onto biofilm covered microplastics and natural substrates. The trace metal adsorption of all the substrates was significantly dependent on pH and ionic strength. The adsorption mechanisms were further analyzed by SEM-EDS and FT-IR. The enhancement of adsorption was mainly attributed to complexation with functional groups contained in the biofilms, including carboxyl, amino, and phenyl-OH. Collectively, biofilm development intensifies the role of MPs in the migration and fate of trace metals in freshwater, since it does not give MPs an edge over natural substrates in adsorption.

Description: Intense bottom-ice algal blooms, often dominated by diatoms, are an important source of food for grazers, organic matter for export during sea ice melt, and dissolved organic carbon. Sea-ice diatoms have a number of adaptations, including accumulation of compatible solutes, that allows them to inhabit this highly variable environment characterized by extremes in temperature, salinity, and light. In addition to protecting them from extreme conditions, these compounds present a labile, nutrient-rich source of organic matter, and include precursors to climate active compounds (e.g., dimethyl sulfide [DMS]), which are likely regulated with environmental change. Here, intracellular concentrations of 45 metabolites were quantified in three sea-ice diatom species and were compared to two temperate diatom species, with a focus on compatible solutes and free amino acid pools. There was a large diversity of metabolite concentrations between diatoms with no clear pattern identifiable for sea-ice species. Concentrations of some compatible solutes (isethionic acid, homarine) approached 1 M in the sea-ice diatoms, Fragilariopsis cylindrus and Navicula cf. perminuta, but not in the larger sea-ice diatom, Nitzschia lecointei or in the temperate diatom species. The differential use of compatible solutes in sea-ice diatoms suggests different adaptive strategies and highlights which small organic compounds may be important in polar biogeochemical cycles.

Description: Highlights • New insights of CH4 and CO2 hydrates are explored using MD strategy. • The bubble evolution appears to be important over dissociation process. • RDF, MSD, AOP, and diffusion coefficient can be used to examine hydrate stability. • The most stable structure of CH4 and CO2 molecules in the gas hydrate is found. • A promising match is noticed between the MD and literature findings. A comprehensive knowledge and precise estimation of the dynamic, structural, and thermodynamic characteristics of hydrates are needed to assess the stability of gas hydrates. Thermodynamic model and experimental studies can be utilized to compute the physical and dynamic properties of hydrate structures. The use of molecular dynamic (MD) simulation is a well-established approach in gas hydrate studies at the atomic level where the properties of interest are obtained from the numerical solution of Newtonian equations. The present work uses MD simulations by employing the constant temperature-constant pressure (NPT), constant temperature-constant volume (NVT) conditions, and the consistent valence force field (CVFF) to monitor the stability and decomposition of methane and carbon dioxide gas hydrates with different compositions. The effects of temperature and composition on the hydrate stability are investigated. In this study, we also compute the radial distribution function, mean square displacement, diffusion coefficient, lattice parameter, potential energy, dissociation enthalpy as well as the density of methane and carbon dioxide under various thermodynamic and process conditions. The formation of methane and carbon dioxide bubbles is studied to investigate bubble evolution during hydrate dissociation. The sizes of methane and carbon dioxide bubbles are not the same due to different solubility conditions of methane and carbon dioxide in liquid water. In addition, the influences of pressure and temperature on the lattice parameter and density of clathrate hydrates are discussed. The obtained results are consistent with previous theoretical and experimental findings, implying that the methodology followed in this work is reliable. The most stable arrangement of methane and carbon dioxide molecules in the gas hydrate is found. The insights/findings of this study might be useful to further understand detailed transport phenomena (e.g., molecular interactions, gas production rate, carbon dioxide replacement, and carbon dioxide capture) involved in the process of carbon dioxide injection into gas hydrate reservoirs.

Description: The morphometric and petrographic characteristics of the coarse-grained clasts (〉 1 cm) sampled from the sediments of the Amerasian Basin, Central Arctic Ocean, were studied. Most of the clasts are represented by dolomites (46,4%), sandstones (22,8%) and limestones (19,8%); the amount of other rocks fragments (chert, shale, igneous) is about 10%. A variety of lithological types were identified among the studied rock fragments. Limestones and dolomitic limestones often contain fragments of fauna. The majority of clasts is poorly rounded and characterized by a wide variety of shapes. More than half of the studied clasts have a size of 1-2 cm, a quarter - 2-3 cm, and larger clasts only occur in insignificant amounts. Geophysical surveys across the sampling sites showed a lack of bedrock outcrops, so the studied coarse-grained clasts are not of local origin. It is concluded that they were predominantly delivered from the Canadian Arctic Archipelago (likely from the platform area, e.g., Victoria Island), mainly due to iceberg rafting during deglaciation periods. The maximum possible contribution of the clasts from the Siberian sources is less than 23%. Distribution of the coarse-grained clasts argues for the existence of a quite stable ice drift path in the past, which is similar to the modern Beaufort Gyre.

Description: The parameterization of the boundary layer is a challenge for regional climate models of the Arctic. In particular, the stable boundary layer (SBL) over Greenland, being the main driver for substantial katabatic winds over the slopes, is simulated differently by different regional climate models or using different parameterizations of the same model. However, verification data sets with high-resolution profiles of the katabatic wind are rare. In the present paper, detailed aircraft measurements of profiles in the katabatic wind and automatic weather station data during the experiment KABEG (Katabatic wind and boundary-layer front experiment around Greenland) in April and May 1997 are used for the verification of the regional climate model COSMO-CLM (CCLM) nested in ERA-Interim reanalyses. CCLM is used in a forecast mode for the whole Arctic with 15 km resolution and is run in the standard configuration of SBL parameterization and with modified SBL parameterization. In the modified version, turbulent kinetic energy (TKE) production and the transfer coefficients for turbulent fluxes in the SBL are reduced, leading to higher stability of the SBL. This leads to a more realistic representation of the daily temperature cycle and of the SBL structure in terms of temperature and wind profiles for the lowest 200 m.

Description: Deep-ocean islands have long been associated with the generation of oceanic eddies in their wakes. However, their interaction with incoming eddies has seldom been considered. This study focuses on the characterization of background and locally generated mesoscale eddies in the Cabo Verde archipelago between 2003 and 2014. Special attention is given to the interaction of incoming eddies with the bathymetry of the islands, along with their impacts on the local generation of eddies. Island-induced wind-shear effects are also considered. In addition, some examples of the biological response to background and locally generated eddies are discussed. This is achieved by combining remote-sensing satellite observations for wind, sea surface height, and chlorophyll-a (Chla) surface concentrations. The results show that the interaction between incoming background eddies and the archipelago is a recurrent phenomenon, which results in eddy deflection, splitting, merging, intensification, and termination (sorted by highest to lowest number of occurrences). Local island-induced disturbances are also significant, mainly due to atmospheric effects. Such processes result in the generation of island-induced eddies and in wind-mediated eddy intensification and confinement, more often observed in the leeward group. Nonetheless, it is strongly suggested that many of the locally generated eddies are a direct product or by-product of the interaction of background eddies with the islands. With respect to the biological realm, a locally generated cyclonic eddy is observed to originate a pronounced phytoplankton bloom in the vicinity of the tallest island. Nonetheless, background eddies generated off the African coast are often associated with enhanced Chla concentrations when they intersect the archipelago. Such observations challenge the idea that local biological productivity in deep oceanic islands is exclusively driven by island-induced mechanisms.

Description: In an era of electronics, recovering the precious metal such as gold from ever increasing piles of electronic-wastes and metal-ion infested soil has become one of the prime concerns for researchers worldwide. Biological mining is an attractive, economical and non-hazardous to recover gold from the low-grade auriferous ore containing waste or soil. This review represents the recent major biological gold retrieval methods used to bio-mine gold. The biomining methods discussed in this review include, bioleaching, bio-oxidation, bio-precipitation, bio-flotation, bio-flocculation, bio-sorption, bio-reduction, bio-electrometallurgical technologies and bioaccumulation. The mechanism of gold biorecovery by microbes is explained in detail to explore its intracellular mechanistic, which help it withstand high concentrations of gold without causing any fatal consequences. Major challenges and future opportunities associated with each method and how they will dictate the fate of gold bio-metallurgy from metal wastes or metal infested soil bioremediation in the coming future are also discussed. With the help of concurrent advancements in high-throughput technologies, the gold bio-exploratory methods will speed up our ways to ensure maximum gold retrieval out of such low-grade ores containing sources, while keeping the gold mining clean and more sustainable.

Description: Arctic summer and winter sea-ice extent is continuously declining as a result of climate change, affecting the hydrography and biogeochemical cycles on the seasonally ice-free Eurasian Shelves. The prolongation of the open-water season causes higher sediment resuspension and coastal erosion due to larger wind fetch and wave heights. This impacts the optical properties of the water column and hence biological productivity in this region. During “Transarktika-2019” leg 1 in late winter 2019, a comprehensive dataset of and optical data was collected throughout the central and northern Barents Sea. Combining suspended particulate matter concentrations obtained from water samples and optical data revealed a pronounced bottom nepheloid layer on the Barents Sea shelf even under ice-covered conditions. Moreover, the data indicate that the Franz Viktoria Trough could be a major pathway for sediment transport into the Eurasian Basin. Therefore, to link changes in sediment distribution and its impact on the ecosystem under a warming climate, further studies of sediment dynamics are required, particularly during winter.

Description: Es ist bekannt, dass unsere Atmosphäre durch vulkanische Gasemissionen geformt wurde. Ebenfalls bekannt ist, dass Vulkane aufgrund ihrer Gas- und Aerosol-Emissionen, insbesondere nach großen explosiven Eruptionen, maßgeblich das Klima beeinflussen. Weit weniger bekannt ist jedoch, dass Vulkane gewissermaßen „wetterfühlige" Gebilde sein können und Vulkan­aktivität vom Wetter und dem Zustand der Atmosphäre beeinflusst werden kann.

Description: Weniger als ein Prozent der längsten Bergkette der Welt sind im Detail erforscht. Dabei finden sich entlang der Mittelozeanischen Rücken faszinierende Ökosysteme, die in völlig lichtloser Umgebung der Ozeane Lebensräume für viele Arten bieten.

Description: Der Magmatismus in Sedimentbecken verursachte globale Massenaussterben und ist die eng ste Analogie zum heutigen anthropogenen Klimawandel. Das Studium dieser natürlichen Prozesse ist oft schwierig, da die Magma-Aufstiegssysteme mit kaum sichtbarer Oberflächen expression verschüttet bleiben. Bei GEOMAR untersuchen wir diese Systeme mit Hilfe von marinen seis-mischen Daten und modernsten numerischen Modellen.

Description: Hochexplosive Vulkanausbrüche können immense Wirkungen auf die Ozonschicht haben und beeinflussen die schädliche UV-Strahlung, die auf der Erde ankommt. Auch kann es vermehrt regnen oder regional durch Verdunklung und Abkühlung zu Missernten kommen. Eine umge­kehrte Wirkung wird ebenfalls diskutiert: Der Klimawandel könnte sich zeitlich versetzt auf vulkanische Aktivität auswirken.

Description: Die meisten Vulkanausbrüche finden dort statt, wo wir sie nur schwer beobachten können: unter Wasser. Ein kleiner Einblick in die noch junge Forschungsdisziplin der Erkundung sub­mariner Vulkane.

Description: An Inselbogenvulkanen können sich im Untergrund, nahe des entgasenden Magmas, Lager­stätten für ökonomisch interessante Metalle wie Kupfer, Molybdän oder Gold bilden.

Description: Rho.do.mi.cro' bi.um. Gr. neut. n. rhodon the rose; Gr. masc. adj. micros small; Gr. masc. n. bios life; N.L. neut. n. Rhodomicrobium red microbe. Proteobacteria / Alphaproteobacteria / Rhizobiales / Hyphomicrobiaceae / Rhodomicrobium Most characteristic for Rhodomicrobium species is the polar cell growth and the characteristic vegetative growth cycle which includes the formation of peritrichously flagellated swarmer cells and nonmotile “mother cells,” which form prosthecae from one to several times the length of the mother cell. Daughter cells originate as spherical buds at the end of the prosthecae and may undergo differentiation in various ways. They are Gram-negative ovoid to elongate-ovoid bacteria belonging to the Alphaproteobacteria. Internal photosynthetic membranes are of the lamellar type. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series. The predominant cellular fatty acid is C18:1, which comprises more than 80% of the membrane-bound fatty acids. Ubiquinone and rhodoquinone with 10 isoprene units are present, and the lipopolysaccharides are characterized by a glucosamine-containing, phosphate-free lipid A with amide-bound C16:0 3 OH. DNA G + C content (mol%): 61.8–63.8. Type species: Rhodomicrobium vannielii Duchow and Douglas 1949.

Description: Proteobacteria Alphaproteobacteria Rhizobiales Hyphomicrobiaceae Blas.to.chlo'ris. Gr. masc. n. blastos bud shoot; Gr. masc. adj. chloros green; N.L. fem. n. Blastochloris green bud shoot. Proteobacteria / Alphaproteobacteria / Rhizobiales / Hyphomicrobiaceae / Blastochloris Blastochloris species are anoxygenic phototrophic Alphaproteobacteria that have bacteriochlorophyll b in their photosynthetic reaction centers. Crystals of the photosynthetic reaction centers of Blastochloris viridis were the first that have been studied in high-resolution structure analysis at 3 Å resolution. Internal photosynthetic membranes are present as lamellae underlying and parallel to the cytoplasmic membrane. Cells are rod shaped to ovoid and exhibit polar growth, budding, and asymmetric cell division and form rosette-like cell aggregates. They are motile by means of subpolar flagella and stain Gram-negative. Straight-chain monounsaturated C18:1 is the predominant component of cellular fatty acids. Ubiquinones and menaquinones are present, and the lipopolysaccharides are characterized by a 2,3-diamino-2,3-deoxy-d-glucose (DAG)-containing, phosphate-free lipid A with amide-bound C14:0 3OH. DNA G + C content (mol%): 63.8–68.3. Type species: Blastochloris viridis (Drews and Giesbrecht 1966) Hiraishi 1997 (Rhodopseudomonas viridis Drews and Giesbrecht 1966).

Description: Rho.do.mi.cro' bi.um. Gr. neut. n. rhodon the rose; Gr. masc. adj. micros small; Gr. masc. n. bios life; N.L. neut. n. Rhodomicrobium red microbe. Proteobacteria / Alphaproteobacteria / Rhizobiales / Hyphomicrobiaceae / Rhodomicrobium Most characteristic for Rhodomicrobium species is the polar cell growth and the characteristic vegetative growth cycle which includes the formation of peritrichously flagellated swarmer cells and nonmotile “mother cells,” which form prosthecae from one to several times the length of the mother cell. Daughter cells originate as spherical buds at the end of the prosthecae and may undergo differentiation in various ways. They are Gram‐negative ovoid to elongate‐ovoid bacteria belonging to the Alphaproteobacteria. Internal photosynthetic membranes are of the lamellar type. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series. The predominant cellular fatty acid is C18:1, which comprises more than 80% of the membrane‐bound fatty acids. Ubiquinone and rhodoquinone with 10 isoprene units are present, and the lipopolysaccharides are characterized by a glucosamine‐containing, phosphate‐free lipid A with amide‐bound C16:0 3 OH. DNA G + C content (mol%): 61.8–63.8. Type species: Rhodomicrobium vannielii Duchow and Douglas 1949.

Description: Particular heavy metals e.g. zinc serve as micronutrients for eukaryotic life and play an important role for cellular metabolism, growth of organisms, reproduction and enzymatic activity. They occur naturally in the environment as trace ingredient in soils, water, rocks, plants and animals. However, in higher concentrations, most heavy metals become toxic and have serious hazard effects on marine biota. Furthermore, they are highly persistent in the marine environment and can be hardly degraded by organisms. Especially coastal environments act as natural catchment basins for anthropogenic pollutants because these areas are highly affected by industry, agriculture and urban runoff. Therefore, it is vitally important to assess past spatial and temporal distribution patterns and to compare those with recent pollution in order to evaluate contemporary emission reduction measures. An emerging paleo-tool is the heavy metal incorporation into foraminiferal shells calcite, which offers monitoring of anthropogenic footprints on the environmental system. Heavy metal records in foraminiferal tests along a sediment core from the North Sea track pollution events of local (e.g. shipyard, ironworks and metallurgy) and global (e.g. market cycles) origin. We analysed the heavy metal concentrations in tests of Ammonia batava (Mn, Zn, Cd Cu etc.) by laser ablation ICP – MS measurements. These metals reveal the pollution history of the North Sea during the last 500 years with focus on the Early Modern Period.

Description: 3rd Report prepared by The World in 2050 initiative

Description: Geological records show that vast proglacial lakes existed along the land terminating margins of palaeo ice sheets in Europe and North America. Proglacial lakes impact ice sheet dynamics by imposing marine-like boundary conditions at the ice margin. These lacustrine boundary conditions include changes in the ice sheet’s geometry, stress balance and frontal ablation and therefore affect the entire ice sheet’s mass balance. This interaction, however, has not been rigorously implemented in ice sheet models. In this study, the implementation of an adaptive lake boundary into the Parallel Ice Sheet Model (PISM) is described and applied to the glacial retreat of the Laurentide Ice Sheet (LIS). The results show that the presence of proglacial lakes locally enhances the ice flow. Along the continental ice margin, ice streams and ice lobes can be observed. Lacustrine terminating ice streams cause immense thinning of the ice sheet’s interior and thus play a significant role in the demise of the LIS. Due to the presence of lakes, a process similar to the marine ice sheet instability causes the collapse of the ice saddle over Hudson Bay, which blocked drainage via the Hudson Strait. In control experiments without a lake model, Hudson Bay is still glaciated at the end of the simulation. Future studies should target the development of parametrizations that better describe the glacial-lacustrine interactions.

Description: Based on the latest GFZ release 06 of monthly gravity fields from GRACE satellite mission, area-averaged barystatic sea-level is found to rise by 2.02 mm/a during the period April 2002 until August 2016 in the open ocean with a 1000 km coastal buffer zone when low degree coefficients are properly augmented with information from satellite laser ranging. Alternative spherical harmonics solutions from CSR, JPL and TU Graz reveal rates between 1.94 and 2.08 mm/a, thereby demonstrating that systematic differences among the centers are much reduced in the latest release. The results from the direct integration in the open ocean can be aligned to associated solutions of the sea-level equation when fractional leakage derived from two differently filtered global gravity fields is explicitly considered, leading to a global mean sea-level rise of 1.72 mm/a. This result implies that estimates obtained from a 1000 km coastal buffer zone are biased 0.3 mm/a high due the systematic omission of regions with below-average barystatic sea-level rise in regions close to substantial coastal mass losses induced by the reduced gravitational attraction of the remaining continental ice and water masses.

Description: Viscoelastic deformations of an earth structure in response to a time-varying surface load are analyzed in glacial isostatic adjustment (GIA). When solving this problem, aspects like flexure of the lithosphere and retarded response of mantle material become evident. Quantified are these by flexural rigidity and relaxation times. The concepts partly lose their relevance when changing from a 1D earth structure (only radial variations) to a 2D or a 3D earth structure (lateral variations). In regions like Fennoscandia and Laurentide, which are affected by GIA, lateral variations of the lithosphere and mantle structure are moderate and, so, the application of a 1D earth structure is widely accepted. But, also for these two regions one has to keep in mind that the respective 1D earth structures differ and that such an approximation mainly holds in the central part of the respective region. In contrast, lateral variations or a local structure of different viscosity have to be considered in areas like Patagonia, Antarctica or Alaska which is located above tectonic activity or covers a region with significant lateral changes in earth structure. But, already for the two former examples one has to keep in mind that the respective 1D earth structures inferred from GIA modelling differ between the two regions. Focusing on the relaxation behavior and the mantle-material transport, we discuss the effect of lateral variations on the deformation process. We will assess to which extent a 1D earth structure can represent lateral variability in structural features, and, at which point a 3D earth structure has to be considered. Such questions are of concern, when discussing GIA for geodetic applications as well as in earth system modeling as this study contributes to the climate modeling initiative Palmod.

Description: 06.02.2022 – 17.02.2022 Port Calls: Kiel – Heligoland – Kiel Areas of Research: Marine Geophysics Institutes: Institute of Geoscience (CAU), Institute of Geography (CAU), AWI Sylt Projects: CDRmare sea4soCiety

Description: In times of accelerating climate change, species are challenged to respond to rapidly shifting environmental settings. Yet, faunal distribution and composition are still scarcely known for remote and little explored seas, where observations are limited in number and mostly refer to local scales. Here, we present the first comprehensive study on Eurasian-Arctic macrobenthos that aims to unravel the relative influence of distinct spatial scales and environmental factors in determining their large-scale distribution and composition patterns. To consider the spatial structure of benthic distribution patterns in response to environmental forcing, we applied Moran’s eigenvector mapping (MEM) on a large dataset of 341 samples from the Barents, Kara and Laptev Seas taken between 1991 and 2014, with a total of 403 macrobenthic taxa (species or genera) that were present in ≥ 10 samples. MEM analysis revealed three spatial scales describing patterns within or beyond single seas (broad: ≥ 400 km, meso: 100–400 km, and small: ≤ 100 km). Each scale is associated with a characteristic benthic fauna and environmental drivers (broad: apparent oxygen utilization and phosphate, meso: distance-to-shoreline and temperature, small: organic carbon flux and distance-to-shoreline). Our results suggest that different environmental factors determine the variation of Eurasian-Arctic benthic community composition within the spatial scales considered and highlight the importance of considering the diverse spatial structure of species communities in marine ecosystems. This multiple-scale approach facilitates an enhanced understanding of the impact of climate-driven environmental changes that is necessary for developing appropriate management strategies for the conservation and sustainable utilization of Arctic marine systems.

Description: Oct. 07 2019 – Oct. 10, 2019 Kiel (Germany) – Kiel (Germany) MNF-Pher-110The main purpose of the ALKOR cruise AL529 was the training of students in observational techniques applied by physical oceanographers. The students who participated in the trip attend the module "Measurement Methods of Oceanography" which is offered in the Bachelor program "Physics of the Earth System" at CAU Kiel. During the AL529 the students were instructed in instrument calibration and in the interpretation of measurement data at sea. In addition, the students had the opportunity to learn about working and living at sea and to explore and study the impact of physical processes in the western Baltic Sea, the sea at their doorstep. The observations show a quasi-synoptic picture of the hydrography and currents in the western Baltic Sea. Twice-repeated hydrographic and current sections across the Fehmarn Belt show well the short time scales where significant changes occur. A zonal section along the deepest topography, from about 10°40'E to 014°21'E, shows very nicely the two-layer system of outflowing low salinity and inflowing North Sea water. A bottom shield anchorage shows the currents in the water column and the near-bottom temperature and salinity variations in the Fehmarnbelt area.

Description: One of the best-known greenhouse gases, CO2, has been increasing in the last decade of about 1.7%. To overcome the well-known global problems related to this gas, researchers of all over the world are working very hard in order to develop any strategies to seriously solve this issue. In this chapter, the authors focus their attention on one of the possible solutions to the problem: bacteria that are CO2 capture cells which have carried out this task since ancient times. In our work we make an excursus on all the biochemical processes of CO2 capture carried out by bacteria, ending with a detailed comparison of the most studied enzymes. One of the alternatives will be to genetically modify the organisms known to date to speed up their conversion process.

Description: Nitrogen fixers, or diazotrophs, play a key role in the carbon and nitrogen cycle of the world oceans, but the controlling mechanisms are not comprehensively understood yet. The present study compares two paradigms on the ecological niche of diazotrophs in an Earth System Model (ESM). In our standard model configuration, which is representative for most of the state-of-the-art pelagic ecosystem models, diazotrophs take advantage of zooplankton featuring a lower food preference for diazotrophs than for ordinary phytoplankton. We compare this paradigm with the idea that diazotrophs are more competitive under oligotrophic conditions, characterized by low (dissolved, particulate, organic and inorganic) phosphorous availability. Both paradigms are supported by observational evidence and lead to a similar good agreement to the most recent and advanced observation-based nitrogen fixation estimate in our ESM framework. Further, we illustrate that the similarity between the two paradigms breaks in a RCP 8.5 anthropogenic emission scenario. We conclude that a more advanced understanding of the ecological niche of diazotrophs is mandatory for assessing the cycling of essential nutrients, especially under changing environmental conditions. Our results call for more in-situ measurements of cyanobacteria biomass if major controls of nitrogen fixation in the oceans are to be dissected.

Description: The MSM89 expedition of Maria S Merian was a contribution to the international research initiative EUREC4A (www.eurec4a.eu). The cruise was carried out in concert with the M161 campaign on RV METEOR (Germany) and the EUREC4A-OA campaign on NO L’ATALANTE (France). Airplane and drone operations as well as well as continuous observations from the ground-based site on the Island of Barbados (BCO) were considered during the MSM89 campaign. Moreover, the cruise was coordinated with ships and Saildrone© operations in the context of the US American ATOMIC project. The overall goal of the EUREC4A field campaign was to collect observational data that will enable research on dynamic and thermodynamic processes in the atmosphere and ocean that will bring the understanding of the role of clouds in the climate system to a new level. MSM89 had its focus on the ocean/atmosphere coupling across ocean mesoscale vortices. For this purpose, both ocean and atmosphere profile measurements were carried out to observe the temporal evolution and spatial heterogeneity of the atmospheric and oceanic boundary layer. Autonomous observing platforms (underwater glider) and a ship towed platform (Cloudkite) augmented the ship-based observations. Incubation experiments were performed to determine Nitrogen fixation rates, the gas exchange for carbon dioxide and oxygen uptake.

Description: The availability of dissolved iron (dFe) exerts an important control on primary production. Recent ocean observation programs have provided information on dFe in many parts of the ocean, but knowledge is still limited concerning the rates of processes that control the concentrations and cycling of dFe in the ocean and hence the role of dFe as a determinant of global primary production. We constructed a three-dimensional gridded dataset of oceanic dFe concentrations by using both observations and a simple model of the iron cycle, and estimated the difference of processes among the ocean basins in controlling the dFe distributions. A Green's function approach was used to integrate the observations and the model. The reproduced three-dimensional dFe distribution indicated that iron influx from aeolian dust and from shelf sediment were 7.6 Gmol yr and 4.4 Gmol yr in the Atlantic Ocean and 0.4 Gmol yr and 4.1 Gmol yr in the Pacific Ocean. The residence times were estimated to be 12.2 years in the Atlantic and 80.4 years in the Pacific. These estimates imply large differences in the cycling of dFe between the two ocean basins that would need to be taken into consideration when projecting future iron biogeochemical cycling under different climate change scenarios. Although there is some uncertainty in our estimates, global estimates of iron cycle characteristics based on this approach can be expected to enhance our understanding of the material cycle and hence of the current and future rates of marine primary production.

Description: 45th IAMSLIC Conference: Port Aransas, TX, USA, 20-25 October 2019, in conjunction with the Annual SAIL Meeting

Description: An automated machine learning framework for geospatial data named PAIRS AutoGeo is introduced on IBM PAIRS Geoscope big data and analytics platform. The frame-work simplifies the development of industrial machine learning solutions leveraging geospatial data to the extent that the user inputs are minimized to merely a text file containing labeled GPS coordinates. PAIRS AutoGeo automatically gathers required data at the location coordinates, assembles the training data, performs quality check, and trains multiple machine learning models for subsequent deployment. The framework is validated using a realistic industrial use case of tree species classification. Open-source tree species data are used as the input to train a random forest classifier and a modified ResNet model for 10-way tree species classification based on aerial imagery, which leads to an accuracy of 59.8% and 81.4%, respectively. This use case exemplifies how PAIRS AutoGeo enables users to leverage machine learning without extensive geospatial expertise.