Session Chair: Vikram Goel; Technical Support: Lindsey Parkinson. The recording of the session is available below.
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08:00 - 08:05 GMT: Introduction
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08:05 - 08:20 GMT: Glacier Bare Ice Mapping From Landsat 8 and Sentinel 2 A Data
Presenter: Dhanendra K. Singh
Institution: HNB Garhwal University, India
Type: Oral Presentation
Abstract: Mapping of bare ice from automated image processing techniques can be a major application for the open source available satellite data of Landsat and Sentinel 2A. There is a wide potential in existing Landsat 8 (OLI) and Sentinel-2 (MSI) time series data for glacier change detection studies. A broadly applied method based on band ratio images from red to shortwave infrared (SWIR) bands can be used for glacier mapping. Band ratios, Red/SWIR, NIR/SWIR, and NDSI can be used for bare ice mapping at different resolution datasets. Here, we tested and compared the techniques to map bare ice area of the glaciers from Landsat 8 and Sentinel 2A, also investigated the change in bare ice area of the glacier, using top of atmosphere reflectance (TOA). It has been reported in the study that Band ratio Red/SWIR (5%) and NIR/SWIR (0.5%) of Landsat 8 resulting larger area than Sentinel 2. The Normalized Difference Snow Index (NDSI) results from Landsat 8 are also (5% larger for 87 glaciers) greater to Sentinel 2. On the other side, extents derived from Landsat 8 (30m) bands are 5% greater, indicating the interpretation of mixed pixels due to a varying resolution of images. GLIMS inventory data used for total glacier area. Mapping of bare ice by Sentinel 2 provided more accurate findings than Landsat 8.
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08:20 - 08:35 GMT: Asymmetry in the Annual Cycle of Antarctic Sea Ice
Presenter: Clare Eayrs
Institution: New York University, Abu Dhabi
Type: Oral Presentation
Abstract: Nearly 16 million square kilometres of sea ice grows and subsequently melts each year in the seas surrounding Antarctica, a sixfold increase in sea ice extent that effectively doubles the size of the continent each winter. The modest increase in Antarctic sea ice cover observed in the satellite record (1.5 % per decade, 1981–2010) masks substantial interannual and regional variability, and recent record maximum (2012–2014) and minimum (2016–2018) sea ice extents further complicate the picture. Despite such interannual variability, each year Antarctic sea ice melts faster than it grows (5 months vs 7 months). Twice-yearly changes in the position and intensity of the zonal winds circling Antarctica are thought to drive the system by working with/against the evolving sea ice edge to slow the autumn advance and hasten the spring melt. Open water regions, created by divergence associated with the zonal winds, amplify the spring melt through increased warming of the upper ocean. We explore these processes using the ERA5 reanalyses (1979–2018), satellite sea ice observations (1979–2018) and the 40 historical ensembles (1920–2005) from the CESM-LENS project. A better understanding of the processes controlling the annual cycle of Antarctic sea ice can provide insight into variability on longer timescales.
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08:35 - 08:45 GMT: Polar areas. We are running out of time (Exhibition)
Presenter: Jhon Fredy Mojica Moncada
Institution: Center for global Sea Level Change, New York University Abu Dhabi
Type: Flash presentation
Abstract: Polar areas represent a thermal condition; they are intimately linked to climate. Over the next century, the climate is projected to warm by several degrees, and worryingly, we are already seeing the loss of glaciers, ice shelf, and permafrost worldwide. This will lead to a rise in sea level affecting millions of people around the world. To raise awareness of this problem, we designed an art installation with 12 blocks of ice, each standing over a water container depicting representative buildings of major coastal cities. The 12 containers were arranged in a clock shape to convey the message that our cryosphere is melting and we are running out of time to do something about it. Over each one, we included a short message showcasing what our institution is doing to study this situation. This installation was presented during the Glimpses exhibition in November 2018 at NYUAD and is available to be used by whoever would like to transmit the message.
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08:45 - 09:00 GMT: Aeolian influences on local soil variability in a changing Arctic landscape
Presenter: Maud van Soest
Institution: Loughborough University, United Kingdom
Type: Oral Presentation
Abstract: Soil forming processes in the Arctic are restricted due to cold temperatures and low microbiological activity. Substantial research has been done on Yedoma Loess deposits (Alaska, Canada and Eurasia), and on soil development in high-altitude proglacial areas. However, limited knowledge is available about the Greenlandic soil landscape, where retreating glaciers are currently creating glacial flour, which is deposited as loess in the nearby areas. The aim of the study was to understand how Arctic soils become colonized and productive under contemporary conditions, focusing on the relative importance of soil-forming processes in comparison to dust inputs. Initially, the local variability in soil characteristics was determined within 5 sites over a transect at set distances from the Greenland Ice Sheet (Kangerlussauq, South West Greenland). Digital soil mapping techniques were used to provide insight on the spatial variation of land cover in relation to topography, and following that, the regression of soil variables. Preliminary results indicate that variations in soil characteristics are mainly influenced by microtopography. Further work could be done on the effects of cryogenic processes and permafrost, since these factors are suspected to change with increasing temperatures. This study highlighted the importance of soil profiles (past) in combination with the quantification of seasonal & annual dust deposition (present), which help to explore how Arctic ecosystems developed since deglaciation, and how they might change under climate change (future).
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09:00 - 09:15 GMT: The Antarctic Biodiversity Portal, an Online Ecosystem for Linking, Integrating and Disseminating Antarctic Biodiversity Information
Presenter: Yi Ming GAN
Institution: Royal Belgian Institute of Natural Sciences, Belgium
Type: Oral presentation
Abstract: The Antarctic Biodiversity portal (biodiversity.aq) is a gateway to a wide variety of Antarctic biodiversity iInformation and tools. Launched in 2015 as the Scientific Committee on Antarctic Research (SCAR) - Marine Biodiversity Information Network (SCAR-MarBIN, scarmarbin.be/) and the Register of Antarctic Marine Species (RAMS, marinespecies.org/rams/), the system has grown in scope from purely marine to also include terrestrial information. Biodiversity.aq is a SCAR product, currently supported as one of the Belgian contributions to the European Lifewatch-European Research Infrastructure Consortium (Lifewatch-ERIC). The goal of Lifewatch is to provide access to: distributed observatories/sensor networks; interoperable databases, existing (data-)networks, using accepted standards; high performance computing (HPC) and grid power, including the use of the state-of-the-art of Cloud and big data paradigms technologies; software and tools for visualization, analysis and modeling. Here we provide an overview of the most recent advances in the biodiversity.aq online ecosystem, a number of use cases as well as an overview of future directions. Some of the most notable components are: The Register of Antarctic Species (RAS, ras.biodiversity.aq) provides an authoritative and comprehensive list of names of marine and terrestrial species in Antarctica and the Southern Ocean. It serves as a reference guide for users to interpret taxonomic literature, as valid names and other names in use are both provided. Integrated Publishing Toolkit (IPT, ipt.biodiversity.aq) allows disseminating Antarctic biodiversity data into global initiatives such as the Ocean Biogeographic Information System (OBIS, obis.org) as Antarctic node of OBIS (Ant-OBIS, also formerly known as SCAR-MArBIN) and the Global Biodiversity Information Facility (GBIF, gbif.org) as Antarctic Biodiversity Information Facility (AntaBIF). Data that can be made available includes metadata, species checklists, species occurrence data and more recently, sampling event- based data. Data from these international portals can be accessed through data.biodiversity.aq. Biodiversity.aq, provides a strong and tested platform for sharing, integrating, discovering and analysing Antarctic biodiversity information originating from a variety of sources into a distributed system.
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09:15 - 09:25 GMT: Bacterial biogeochemical cycling in the Himalayan cryoconite holes
Presenter: Milind Mutnale
Institution: National Centre for Polar and Ocean Research, India
Type: Flash presentation
Abstract: Cryoconite holes are sediment and water-rich depression found on the glacial ice. Cryospheric environments are usually nutrient scarce, but the organic matter present in the cryoconite hole provides the nutrients to nearby surrounding area, thereby providing refuge to the resident microorganisms. Cryoconite holes are known to harbour unique and diverse microbes including prokaryotes, eukaryotes and microscopic animal such as tardigrade. Nutrient recycling by these microbes is crucial for their survival in the cryoconite hole as it contains limited resources. Cryoconite sediments being of lithogenic sources contain metals and elements such as Manganese, Iron, and Sulphur which play a vital role in the growth of living organisms. Therefore, the ability of microbes to recycle these metals becomes extremely important for cryoconite hole ecosystems. Thus this study aims to identify different microbes and their functional genes involved in the biogeochemical cycling of essential elements such as Manganese, Iron, and Sulphur from the Himalayan cryoconite holes. A total of 23 samples were collected from the Sutri Dhaka Glacier in Western Himalaya, from which a total of 43 different species of bacteria have been identified. Preliminary results identified by DNA sequencing shows that seven of the isolated microbes show potential for Sulphur oxidation, ten for Manganese oxidation/reduction, and five are iron oxidizers. This study will help us understand various mechanisms that the microbes pose to recycle the nutrient in the environment. Their potential functional genes can be studied to gain in-depth knowledge of microbial evolution and adaptations in these habitats.
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09:25 - 09:35 GMT: OMI-perm - Organo-Mineral Interactions from permafrost disturbance to sediment sink
Presenter: Julien Fouché
Institution: Vrije Universiteit Amsterdam, Netherlands
Type: Flash presentation
Abstract: Permafrost soils store large amounts of organic matter (OM), which upon thaw are exposed to decomposition, thereby generating greenhouse gases that fuel further global warming. Permafrost thaw is also expected to increase the hydraulic conductivity of the landscape, allowing for the enhanced release of OM to the aquatic environment. Here it can either be decomposed further or buried and removed from active carbon cycling. Close association between OM and mineral matrices are thought to protect permafrost OM from decomposition, yet, how this complex interplay of different mechanisms evolves during transit is still insufficiently understood. We would like to present our upcoming fieldwork campaign funded by INTERACT, aiming to investigate the role of organo-mineral associations during lateral transport in the Zackenberg valley, Northeastern Greenland. We plan to collect soil samples from the active layer and permafrost at places of abrupt thaw, water samples and stream sediments along the release path, as well as water and sediment samples close to where the material is discharged into Young Sound. For all these samples we will characterize the OM and mineral composition both quantitatively and qualitatively. With this project we aim to breach disciplinary boundaries in two ways: By following material released from permafrost soils along the flow path to its sedimentary sink, we bring together soil and marine scientists and at the same time integrate studies on OM and the mineral matrix. Our complimentary backgrounds of organic biogeochemistry, soil science and mineralogy nicely combine to tackle this interdisciplinary research topic.
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09:40 - 10:15 GMT: Keynote: Reflections on an atypical decade of marine sampling
Presenter: Narissa Bax
Institution: Institute for Marine and Antarctic Studies (IMAS), Tasmania
Type: Keynote Presentation
Abstract: Securing specimens in the long-term is particularly important in areas such as Antarctica that may be among the first to be impacted by global- scale issues including climate change and ocean acidification. Appropriate curation and maintenance of these baseline assets is, however, often discounted against competing funding priorities. A coordinated approach is needed to realise the potential of the material collected across an atypical decade of increased Antarctic sampling (2009 - 2019).
These collections represent important baseline information on the biodiversity, species taxonomy, biogeography, biology and ecology of marine ecosystems in the Antarctic. These collections are often the only existing specimens from particular areas or habitats, and contain representatives of rarely collected, and in some cases, new or undescribed species.
Antarctic marine biological collections represent a unique scientific asset from rarely sampled, remote locations that are logistically difficult and expensive to access. Preserved biological specimens are assets for the collecting organisations, the scientific community, and most importantly, future generations of researchers and the general public. Furthering this discussion at the APECS conference is a timely opportunity to engage the international community of early career Polar researchers towards managing biological specimens collected during interdisciplinary collaborations.
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10:15 - 10:30 GMT: Spatial variability in total and organic mercury levels in Antarctic krill Euphausia superba across the Scotia Sea
Presenter: José Seco
Institution: University of Aveiro, Portugal & University of St. Andrews, UK
Type: Oral presentation
Abstract: Total and organic mercury concentrations were determined for males, females and juveniles of Euphausia superba collected at three discrete locations in the Scotia Sea (South Orkney Islands, South Georgia and Antarctic Polar Front) to assess spatial mercury variability in Antarctic krill. There was clear geographic differentiation in mercury concentrations, with specimens from the South Orkney Islands having total mercury concentrations 5 to 7 times higher than Antarctic krill from South Georgia and the Antarctic Polar Front. Mercury did not appear to accumulate with life-stage since juveniles had higher concentrations of total mercury than adults. Results suggest that females may use egg laying as a mechanism to excrete mercury, with eggs having higher concentrations than the corresponding somatic tissue. Organic mercury makes up a minor percentage of total mercury with the percentage being greater in adults than in juveniles. When compared to euphausiids from other parts of the world, the concentration of mercury in Antarctic krill is within the same range, or higher, high- lighting the global distribution of this contaminant. Given the high potential for biomagnification of mercury through food webs, concentrations in Antarctic krill may have deleterious effects on long-lived Antarctic krill predators.
APECS Online Conference 2019 - Session-1 from APECS Webinars on Vimeo.