DOI: 10.5281/zenodo.7956516
title: SNOWPACK simulations forced by MERRA-2 for Antarctic Ice Shelves

description: This repository contains the SNOWPACK simulations used in the manuscript:<br> Banwell, A., Wever, N., Dunmire, D. and Picard, G. (2023): <em>Quantifying Antarctic-wide ice-shelf surface melt volume using microwave and firn model data: 1980 to 2021.</em> Geophys. Res. Lett. (accepted). For each MERRA-2 grid point that is on an ice shelf, the zip file of the corresponding simulation is named: &lt;latitude&gt;_&lt;longitude&gt;_ICESHELVES.zip Each zip file then contains the following files: <code>output/-72.000_69.375_ICESHELVES.ini</code>: This file contains the model settings as used for the simulation <code>output/-72.000_69.375_ICESHELVES.pro</code>: This file contains the detailed, layered SNOWPACK output, with for each layer, for example, temperature, density, liquid water content, grain size, etc. Can be visualized using niViz. <code>output/-72.000_69.375_ICESHELVES.smet</code>: This file contains the SNOWPACK time series output, like surface sublimation, snow surface temperature, latent heat flux, etc. Can be visualized using niViz. <code>output/-72.000_69.375_ICESHELVES.sno</code>: This file contains the SNOWPACK model state at the end of the simulation. <code>output/-72.000_69.375_ICESHELVES.snobackup</code>: This file contains the SNOWPACK model state from the last backup point during the simulation. <code>output/-72.000_69.375_ICESHELVES.haz</code>: This file contains very specific SNOWPACK model output and was ignored in the study associated with this dataset. <code>output/-72.000_69.375_ICESHELVES.hazbackup</code>: This file contains very specific SNOWPACK model output from the last backup point during the simulation and was ignored in the study associated with this dataset. Also available are statistics derived from the SNOWPACK model output using the code published at doi: 10.5281/zenodo.7957639 (GitHub repository): <code>statistics.zip</code><br> ========== Contains statistics calculated from the SNOWPACK output. Statistics per region are stored in the folders <code>stats622</code> (for yearly statistics) and <code>stats_per_day622</code> (for daily statistics). Statistics per ice shelf are stored in the folders <code>stats_iceshelves622</code> (for yearly statistics) and <code>stats_iceshelves_per_day622</code> (for daily statistics). For each ice shelf and region, the following files are available: melt_R<em>X</em>.txt and melt_S<em>X</em>.txt: sum of melt amount (kg/m2) for region R<em>X</em> or ice shelf S<em>X</em>, respectively. meltdays_<em>A</em>mm_R<em>X</em>.txt and meltdays_<em>A</em>mm_S<em>X</em>.txt: number of days exceeding <em>A</em> mm of melt for region R<em>X</em> or ice shelf S<em>X</em>, respectively. mswater_<em>A</em>mm_R<em>X</em>.txt and mswater_<em>A</em>mm_S<em>X</em>.txt: number of days with total firn column water content exceeding <em>A</em> kg/m2 for region R<em>X</em> or ice shelf S<em>X</em>, respectively. mswater<em>A</em>_<em>B</em>_<em>C</em>mm_R<em>X</em>.txt and mswater<em>A</em>_<em>B</em>_<em>C</em>mm_S<em>X</em>.txt: number of days with more than <em>C</em> kg/m2 amount of liquid water in the firn between <em>A</em> and <em>B</em> meters below the surface for region R<em>X</em> or ice shelf S<em>X</em>, respectively. Each of the files report the year, respectively the date, in the first column, followed by the statistics for each grid point in the region/ice shelf, followed by the mean and standard deviation over all grid points in the respective region/ice shelf listed in the preceding columns. The first line is a header. To find out the sequence by which MERRA-2 points appear in the output columns, please refer to the list in the file <code>list_points.txt</code>. This list is constructed as follows. First there is a header indicating that what follows are regions. Then, each line contains a comma-delimited list of the region number, latitude, and longitude, respectively. The first line for a region is reported in the column with header <code>1</code> in the statistics file, the second line in the column with header <code>2</code>, and so on. After all regions are listed, there is again a header line denoting that what follows are the ice shelves. Similar to the section for the regions, each following line contains a comma-delimited list of the ice shelf number, latitude, and longitude, respectively. The numbering of regions and ice shelves is listed in the tables below. <code>forcingstatistics.zip</code><br> =============== Contains monthly statistics of the forcing variables TA (air temperature, K), QI (specific humidity, -), ILWR (incoming longwave radiation W/m2), ISWR (incoming shortwave radiation, W/m2), PSUM (precipitation, kg/m2/h), and VW (wind speed, m/s). The statistics for each region and ice shelf are stored in <code>monthlystats</code> and <code>monthlystats_iceshelves</code>, respectively. Each file name contains the forcing variable and the region/ice shelf number. The numbering of regions and ice shelves can be found in the tables below. Each file then contains the month (expressed as YYYYMM), followed by means of the specific variable for each MERRA-2 grid point in the region/ice shelves (in the same sequence as for the statistics files discussed above), followed by the mean and standard deviation over all MERRA-2 grid points listed in the preceding columns. Regions Number R1 Amery R2 Amundsen R3 Dronning R4 Peninsula R5 Ronne R6 Ross R7 Victoria R8 Wilkes Ice shelves S115 Amery S102 West S104 Publications S53 Venable S110 Abbot S54 Cosgrove S55 PIG S56 Thwaites S57 Crosson S58 Dotson S60 Getz S64 Nickerson S65 Sulzberger S36 Brunt S37 Riiser-Larsen S38 Quar S39 Ekstrom S124 Atka S125 Jelbaert S121 Fimbil S123 Vigrid S122 Nivlisen S120 Lazarez S119 Borchgrevink S118 Baudouin S158 Prince Herald S51 Scar Inlet S8 Larsen C S6 Larsen D S7 Larsen E S45 N GVIIS S44 S GVIIS S46 Bach S52 Stange S50 Wilkins S34 Ronne S35 Filchner S70 Ross West S71 Ross East S91 Mertz S162 Ninnis S90 Cook S86 Rennick S83 Mariner S73 Drygalski S74 Nansen S114 Dibble S100 Shackleton S24 Tracy Tremenchus S99 Conger Glenzer S159 Vincennes Bay S98 Totten S157 Moscow uni S156 Holmes