.. _vx-data-gdas-ice: GDAS: Ice ========= Description "The Global Data Assimilation System (GDAS) is the system used by the National Center for Environmental Prediction (NCEP) Global Forecast System (GFS) model to place observations into a gridded model space for the purpose of starting, or initializing, weather forecasts with observed data." from NOAA NCEI Sample image Categorical freezing rain. .. image:: images/gdas_frzr.png :width: 600 Recommended use "Place observations into a gridded model space for the purpose of starting, or initializing, weather forecasts with observed data” from NOAA NCEI File format * Grib2 Location of data NCDC/NCEI: https://www.ncdc.noaa.gov/data-access/model-data/model-datasets/global-data-assimilation-system-gdas Ice data is in the first two rows in the "Product Types" table. Access restrictions None Spatial resolution, grid, or coverage The spatial coverage is as follows. Latitude: 90.000000 to -90.000000 Longitude: 0.000000 to 359.750000 There are three spatial resolution options: 1° by 1°, 0.5° by 0.5°, and 0.25° by 0.25° Temporal resolution * Model cycle: 4/day: 00, 06, 12, 18UTC * Output Timestep: Anl, +00, +03, +06, +09 hours Starting and/or ending dates * Historical Dataset: 21Apr2019 – 11May2020 * Present Dataset: 05Jun2020 – Present Data latency Present data set appears to be a 6-7 day latency (no documented latency) Variables available Here is a list of relevant variables. There are more in the grib2 files. * Cloud mixing ratio, CMWR * Ice water mixing ratio, IWMR * Rain water mixing ratio, RWMR * Snow Mixing Ratio, SNMR * Graupel, GRLE * Ice concentration [ice=1, no ice=0], CI * Ice Growth Rate, ICEG * Percent frozen precipitation, CPOFP * Precipitation Rate, PRATE * Categorical Snow, CSNOW * Categorical Ice Pellets, CICEP * Categorical Freezing Rain, CFRZR * Categorical Rain, CRAIN * Snow depth, SNOD * Water equiv. of accum. snow depth, SDWE METplus Use Cases Link to `METplus Use Cases `_ for this dataset. Keywords .. note:: **Current Dataset:** VxDataGDAS .. note:: **Data Labels:** DataTypeGridded, DataLevelSurface, DataProviderNOAA, DataApplicationPrecipitation, DataApplicationMarineAndCryo