Datasets of the deliverable D3.1 - EO: Contribution of continental scale ice dynamics processes to freshwater fluxes

This dataset provides spatially and temporally standardized freshwater fluxes from ice shelves around Antarctica, as well as ice-shelf integrated estimates. It is based on state-of-the-art and open-source datasets (Paolo et al., 2023; Greene et al., 2022; Mouginot et al., 2017; Morlighem et al., 2019) and contains the following data files:1- iceshelf_calving_fluxes.gpkg2- Merged_Integrated_melt_rates.csv3- Merged_Integrated_melt_err_rates.csv4- calving_bmachine_grid_v1.nc5- bmelt_bmachine_grid_v1.nc You can find below a brief description of this dataset (more information on the calculation can be found in the README file). 1) "iceshelf_calving_fluxes.gpkg" is a geopackage file that can be read inside QGIS. It contains the delimitation of ice shelves, based on the grounding line, ice front delineation, and naming convention from Mouginot et al, 2017. The dataset contains the following columns:- fid: ice shelf id - ice_shelf_name : ice_shelf_name based on the naming convention from Mouginot et al., 2017- latitude : latitude of the ice shelf- longitude : longitude of the ice shelf- mass_change_YY : ice shelf calving rate in Gt/yr.- mass_change_YY_err : error on ice shelf calving rate in Gt/yr. 2) "Merged_Integrated_melt_rates.csv" contains the following variable- Column 1: ice shelf names based on the same convention as calving (see previous paragraph)- Column 2-26: integrated basal melting rates in Gt/yr water equivalent, for years 1992 and 1994-2017 based on the dataset of Paolo et al., 2023. 3) "Merged_Integrated_melt_err_rates.csv" contains the following variable- Column 1: ice shelf names based on the same convention as calving (see previous paragraph)- Column 2-26: integrated error on basal melting rates in Gt/yr water equivalent, for years 1992 and 1994-2017, based on the dataset of Paolo et al., 2023. 4) "calving_bmachine_grid_v1.nc" is a netCDF that contains spatially distributed maps of calving rates in Gt/yr and related errors (Greene et al., 2022) along with ice shelf thicknesses (Paolo et al., 2023) for overlapping years, based on the flux calculation at the ice shelf front (using the mask from "iceshelf_calving_fluxes.gpkg"). The projection is polar stereographic (EPSG:3031), and the pixel size is 500 m. The extent of the layers is the same as BedMachine v3. 5) "bmelt_bmachine_grid_v1.nc" is a netCDF that contains spatially distributed maps of yearly basal melting rates in meters/year and related errors, based on the work of Paolo et al., 2023. The maps of basal melting have also been reprojected into the BedMachine grid (same as calving rates), which is in polar stereographic projection (EPSG:3031) with a pixel size of 500 m. ReferencesMouginot, J., B. Scheuchl, and E. Rignot. (2017). MEaSUREs Antarctic Boundaries for IPY 2007-2009 from Satellite Radar, Version 2 [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/AXE4121732AD. Date Accessed 07-25-2023. Greene, C. A., Gardner, A. S., Schlegel, N.-J., & Fraser, A. D. (2022). Antarctic calving loss rivals ice-shelf thinning. Nature, 609(7929), 948–953. https://doi.org/10.1038/s41586-022-05037-w Paolo, F. S., Gardner, A. S., Greene, C. A., Nilsson, J., Schodlok, M. P., Schlegel, N.-J., and Fricker, H. A.: Widespread slowdown in thinning rates of West Antarctic ice shelves, The Cryosphere, 17, 3409–3433, https://doi.org/10.5194/tc-17-3409-2023, 2023. Morlighem, M., Rignot, E., Binder, T., Blankenship, D., Drews, R., Eagles, G., et al. (2019). Deep glacial troughs and stabilizing ridges unveiled beneath the margins of the Antarctic ice sheet. Nature Geoscience, 1–6. https://doi.org/10.1038/s41561-019-0510-8本数据集提供了南极洲周边冰架的时空标准化淡水通量，以及冰架整体估算结果。其基于当前最先进的开源数据集（Paolo等，2023；Greene等，2022；Mouginot等，2017；Morlighem等，2019），包含以下数据文件： 1. "iceshelf_calving_fluxes.gpkg" 2. "Merged_Integrated_melt_rates.csv" 3. "Merged_Integrated_melt_err_rates.csv" 4. "calving_bmachine_grid_v1.nc" 5. "bmelt_bmachine_grid_v1.nc" 下文为该数据集的简要说明（计算细节详见README文件）。 1) "iceshelf_calving_fluxes.gpkg"为可在QGIS（Quantum GIS，量子地理信息系统）中读取的GeoPackage（地理数据包）文件。其包含基于Mouginot等（2017）的接地线、冰前沿划定与命名规范的冰架边界。该数据集包含以下字段： - fid：冰架编号 - ice_shelf_name：基于Mouginot等（2017）命名规范的冰架名称 - latitude：冰架纬度 - longitude：冰架经度 - mass_change_YY：以Gt/yr（吉吨每年）为单位的冰架崩解速率 - mass_change_YY_err：以Gt/yr（吉吨每年）为单位的冰架崩解速率误差 2) "Merged_Integrated_melt_rates.csv"包含以下变量： - 第1列：采用与崩解数据一致命名规范的冰架名称（详见前文） - 第2至26列：基于Paolo等（2023）数据集的1992年及1994-2017年冰架底部整体消融速率（以水当量Gt/yr为单位） 3) "Merged_Integrated_melt_err_rates.csv"包含以下变量： - 第1列：采用与崩解数据一致命名规范的冰架名称（详见前文） - 第2至26列：基于Paolo等（2023）数据集的1992年及1994-2017年冰架底部消融速率的整体误差（以水当量Gt/yr为单位） 4) "calving_bmachine_grid_v1.nc"为netCDF（网络通用数据格式，Network Common Data Form）文件，包含以冰架前沿通量计算为基础的、重叠年份的崩解速率空间分布栅格及对应误差（Greene等，2022），同时包含冰架厚度数据（Paolo等，2023），所用掩膜来自"iceshelf_calving_fluxes.gpkg"。该数据集采用极地方向投影（EPSG:3031），像素分辨率为500米，图层范围与BedMachine v3（冰床机版本3）一致。 5) "bmelt_bmachine_grid_v1.nc"为netCDF（网络通用数据格式，Network Common Data Form）文件，包含基于Paolo等（2023）研究的、以米/年为单位的冰架底部年消融速率空间分布栅格及对应误差。消融速率栅格已重投影至与崩解数据一致的BedMachine网格（同样采用极地方向投影EPSG:3031，像素分辨率500米）。 参考文献 Mouginot, J., B. Scheuchl, 与 E. Rignot. (2017). 基于卫星雷达的IPY 2007-2009年南极边界数据集（第2版）[数据集]. 美国科罗拉多州博尔德: 美国国家航空航天局国家冰雪数据中心分布式主动存档中心. https://doi.org/10.5067/AXE4121732AD. 数据获取日期: 2023-07-25. Greene, C. A., Gardner, A. S., Schlegel, N.-J., 与 Fraser, A. D. (2022). 南极崩解损失与冰架变薄相当. 《自然》, 609(7929), 948–953. https://doi.org/10.1038/s41586-022-05037-w Paolo, F. S., Gardner, A. S., Greene, C. A., Nilsson, J., Schodlok, M. P., Schlegel, N.-J., 与 Fricker, H. A.: 西南极冰架变薄速率普遍放缓, 《冰冻圈》, 17, 3409–3433, https://doi.org/10.5194/tc-17-3409-2023, 2023. Morlighem, M., Rignot, E., Binder, T., Blankenship, D., Drews, R., Eagles, G., 等. (2019). 南极冰盖边缘下的深切冰槽与稳定脊. 《自然·地球科学》, 1–6. https://doi.org/10.1038/s41561-019-0510-8