tsgettoolbox.tsgettoolbox.ldas_grace

tsgettoolbox.tsgettoolbox.ldas_grace(lat=None, lon=None, variables=None, startDate=None, endDate=None, variable=None)

NAmerica:0.125deg:2002-:7D:Groundwater and soil moisture from GRACE

The time zone is always UTC.

The Gravity Recovery and Climate Experiment (GRACE) twin satellites, which orbited Earth from 2002 to 2017, made detailed measurements of Earth’s gravity field and improved investigations about Earth’s water reservoirs, over land, ice and oceans.

GRACE measured gravity by relating it to the distance between the two satellites. When there was an increase in gravity ahead of the pair, the front satellite sped up and the distance between the pair increased. When the increased gravity was between the pair, their distance decreased; the opposite occurred when there was decreased gravity ahead of, or between, the satellite pair.

The satellites were separated by 220 km, and they could detect changes smaller than a micrometer per second in relative velocity. These measurements, in conjunction with other data and models, provided observations of terrestrial water storage changes, ice-mass variations, ocean bottom pressure changes and sea-level variations.

GRACE was a collaboration of the US and German space agencies (NASA and DLR). The key partners were the University of Texas Center for Space Research (CSR), the GeoForschungsZentrum (GFZ) Potsdam, and the Jet Propulsion Laboratory (JPL).

Description/Name

Spatial

Lat Range

Lon Range

Time

Groundwater and Soil Moisture Conditions from GRACE Data Assimilation GRACEDADM_CLSM0125US_7D V4.0

0.125x0.125

25, 53

-125, -67

7 day 2002-10-04 to recent
Parameters:

  • lat (float) – Latitude (required): Enter single geographic latitude point. Use positive values for the northern hemisphere and negative for the southern hemisphere. The valid range is specified in the table above.

  • lon (float) – Longitude (required): Enter single geographic longitude point. Use positive for the eastern hemisphere and negative for the western hemisphere. The valid range is specified in the table above.

  • variables (str) –

    For the command line a comma separated string of variable codes from the following table. Using the Python API a list of variable strings. Valid variable names are specified in the table below.

    LDAS “variables” string

    Description

    Units

    GRACEDADM_CLSM0125US_7D_4_0_gws_inst

    Groundwater storage percentile

    percent

    GRACEDADM_CLSM0125US_7D_4_0_rtzsm_inst

    Root zone soil moisture percentile

    percent

    GRACEDADM_CLSM0125US_7D_4_0_sfsm_inst

    Surface soil moisture percentile

    percent

  • startDate (str) –

    The start date of the time series.:

    Example: --startDate=2001-01-01T05

    If startDate and endDate are None, returns the entire series.

  • endDate (str) –

    The end date of the time series.:

    Example: --endDate=2002-01-05T05

    If startDate and endDate are None, returns the entire series.

  • variable (str) – DEPRECATED: use “variables” instead to be consistent across “tsgettoolbox”.