TY - JOUR A1 - Voglimacci-Stephanopoli, Joëlle A1 - Wendleder, Anna A1 - Lantuit, Hugues A1 - Langlois, Alexandre A1 - Stettner, Samuel A1 - Schmitt, Andreas A1 - Dedieu, Jean-Pierre A1 - Roth, Achim A1 - Royer, Alain T1 - Potential of X-band polarimetric synthetic aperture radar co-polar phase difference for arctic snow depth estimation JF - Cryosphere N2 - Changes in snowpack associated with climatic warming has drastic impacts on surface energy balance in the cryosphere. Yet, traditional monitoring techniques, such as punctual measurements in the field, do not cover the full snowpack spatial and temporal variability, which hampers efforts to upscale measurements to the global scale. This variability is one of the primary constraints in model development. In terms of spatial resolution, active microwaves (synthetic aperture radar - SAR) can address the issue and outperform methods based on passive microwaves. Thus, high-spatial-resolution monitoring of snow depth (SD) would allow for better parameterization of local processes that drive the spatial variability of snow. The overall objective of this study is to evaluate the potential of the TerraSAR-X (TSX) SAR sensor and the wave co-polar phase difference (CPD) method for characterizing snow cover at high spatial resolution. Consequently, we first (1) investigate SD and depth hoar fraction (DHF) variability between different vegetation classes in the Ice Creek catchment (Qikiqtaruk/Herschel Island, Yukon, Canada) using in situ measurements collected over the course of a field campaign in 2019; (2) evaluate linkages between snow characteristics and CPD distribution over the 2019 dataset; and (3) determine CPD seasonality considering meteorological data over the 2015-2019 period. SD could be extracted using the CPD when certain conditions are met. A high incidence angle (>30 circle) with a high topographic wetness index (TWI) (>7.0) showed correlation between SD and CPD (R2 up to 0.72). Further, future work should address a threshold of sensitivity to TWI and incidence angle to map snow depth in such environments and assess the potential of using interpolation tools to fill in gaps in SD information on drier vegetation types. Y1 - 2022 U6 - https://doi.org/10.5194/tc-16-2163-2022 SN - 1994-0416 SN - 1994-0424 VL - 16 IS - 6 SP - 2163 EP - 2181 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Grotheer, Hendrik A1 - Meyer, Vera A1 - Riedel, Theran A1 - Pfalz, Gregor A1 - Mathieu, Lucie A1 - Hefter, Jens H. A1 - Gentz, Torben A1 - Lantuit, Hugues A1 - Mollennauer, Gesine A1 - Fritz, Michael T1 - Burial and origin of permafrost-derived carbon in the nearshore zone of the southern Canadian Beaufort Sea JF - Geophysical research letters N2 - Detailed organic geochemical and carbon isotopic (delta C-13 and Delta C-14) analyses are performed on permafrost deposits affected by coastal erosion (Herschel Island, Canadian Beaufort Sea) and adjacent marine sediments (Herschel Basin) to understand the fate of organic carbon in Arctic nearshore environments. We use an end-member model based on the carbon isotopic composition of bulk organic matter to identify sources of organic carbon. Monte Carlo simulations are applied to quantify the contribution of coastal permafrost erosion to the sedimentary carbon budget. The models suggest that similar to 40% of all carbon released by local coastal permafrost erosion is efficiently trapped and sequestered in the nearshore zone. This highlights the importance of sedimentary traps in environments such as basins, lagoons, troughs, and canyons for the carbon sequestration in previously poorly investigated, nearshore areas. Plain Language Summary Increasing air and sea surface temperatures at high latitudes leads to accelerated thaw, destabilization, and erosion of perennially frozen soils (i.e., permafrost), which are often rich in organic carbon. Coastal erosion leads to an increased mobilization of organic carbon into the Arctic Ocean, which there can be converted into greenhouse gases and may therefore contribute to further warming. Carbon decomposition can be limited if organic matter is efficiently deposited on the seafloor, buried in marine sediments, and thus removed from the short-term carbon cycle. Basins, canyons, and troughs near the coastline can serve as sediment traps and potentially accommodate large quantities of organic carbon along the Arctic coast. Here we use biomarkers (source-specific molecules), stable carbon isotopes, and radiocarbon to identify the sources of organic carbon in the nearshore zone of the southern Canadian Beaufort Sea near Herschel Island. We quantify the contribution of coastal permafrost erosion to the sedimentary carbon budget of the area and estimate that more than a third of all carbon released by local permafrost erosion is efficiently trapped in marine sediments. This highlights the importance of regional sediment traps for carbon sequestration. Y1 - 2020 U6 - https://doi.org/10.1029/2019GL085897 SN - 0094-8276 SN - 1944-8007 VL - 47 IS - 3 PB - Wiley CY - Hoboken, NJ ER -