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HMS: Hydrologic Micro Services

Meteorology - Radiation

NLDAS Radiation

The North American Land Data Assimilation System (NLDAS) combines North American radar data and satellite data from CMORPH (https://www.cpc.ncep.noaa.gov/products/janowiak/cmorph_description.html). NLDAS has a one-hour time step on a 0.125-degree grid of North America, with an average time delay of four days for data retrieval. NLDAS has data coverage from January 1, 1979 to the present. NLDAS data are reported in UTC (GMT). Temporal aggregations are provided as averages calculated from smaller timesteps.

GLDAS Radiation

The Global Land Data Assimilation System (GLDAS) combines satellite data and ground-based observational data to provide radiation and other meteorological parameters. GLDAS has a three-hour time step on a global 0.25-degree grid. GLDAS-2.1 provides data coverage from January 1, 2000 to present, with an average time delay of one month for data retrieval. GLDAS data are reported in UTC (GMT). Temporal aggregations are provided as averages calculated from smaller timesteps.

DAYMET Radiation

DAYMET is a daily dataset of radiation data that has been interpolated and extrapolated. DAYMET uses ground station data with their model algorithm to produce gridded estimates of daily weather parameters. The interpolated spatial resolution is about a 0.009-degree grid over North America. Data is accessible since 1980 to the latest full year. DAYMET discards values for December 31 from leap years to maintain a 365-day year. DAYMET data are reported in UTC (GMT).Temporal aggregations are provided as averages calculated from smaller timesteps.

Temporal Aggregations

The available temporal aggregations are dependent upon the native timestep size of the data source. Possible options include 'daily', for those sources which are not by default daily, and 'monthly'. Aggregated radiation data are the averages over these time periods and provided in the aggregated timeseries. Monthly aggregations correspond to the calendar month, and require the entire month to be specified in the date time span.