This data set is only available for a restricted user group, please contact us if you want to access these data.
RESTRICTED only accessable in CEN/MPI net or via CliSAP login What does that mean?
GLEAM stands for Global Land Evaporation Amsterdam Model and describes a suite of algorithms that separately estimate the different components of the terrestrial evaporation. This is done based on data from various satellite observations and atmospheric re-analyses.
Estimated are the actual evaporation and its components (see parameters) as well as the evaporative stress factor. Among the components are, e.g., the potential evaporation which is computed from surface net radiation and near-surface air temperature data using a Priestley & Taylor equation. By means of the evaporative stress factor, which is based on computations of vegetation optical depth from microwave observations and simulated root-zone soil moisture content, the actual evaporation is derived. The root-zone soil moisture is calculated using a multi-layer running water balance model which uses observed precipitation as input and which assimilates soil moisture observations. Rainfall and vegetation characteristics are used together with observed precipitation in a Gash analytical model for the estimation of the interception loss.
For more information we refer to the references.
We offer GLEAM v3.3a. This product covers the longer time period of the two latest GLEAM products. The other product, v3.3b, covers basically the observation period of MODIS, and is available via www.GLEAM.eu.
Last update of this data set at ICDC: May 23, 2019; wrong units of the monthly fluxes were corrected October 16, 2020.
|Evaporation||mm / day or month||actual evaporation|
|Potential evaporation||mm / day or month||if water supply would be unlimited|
|Bare-soil evaporation||mm / day or month|
|Open water evaporation||mm / day or month||over irrigated areas, coastal and shorelines|
|Interception loss||mm / day or month||evaporation directly from the plant surfaces, e.g. after rain|
|Transpiration||mm / day or month||evaporation of plants, e.g. through stomata|
|Snow sublimation||mm / day or month|
|Evaporative stress (factor)||0 ... 1|
|Root-zone soil moisture||m^3 / m^3|
|Near-surface soil moisture||m^3 / m^3||0 ... 10 cm depth|
Period and temporal resolution:
- Daily: 1980-01-01 to 2018-12-31
- Monthly: 1980-01 to 2018-12
Coverage and spatial resolution:
- Spatial resolution: 0.25° x 0.25°, Climate modeling grid
- Geographic longitude: 179.875°W to 179.875°E
- Geographic latitude: 89.875°S to 89.875°N
- Dimension: 720 rows x 1440 columns
- Altitude: following terrain
This data set does not contain any uncertainty information.
Details about the accuracy and the representativity of the data sets can be found under www.GLEAM.eu and in the README document. The latter includes, for instance, a list of relevant literature, which is extended compared to the references, an overview about the input data sets in Table 1, and information about the most relevant changes compared to version v3.2 and version v3.1.
Among the possibly most relevant changes are (v3.3a versus v3.2a):
- Usage of ERA5 instead of ERA-Interim
- Usage of dyanmic land cover information (MEaSUREs Vegetation Continuous Fraction)
- Usage of ESA-CCI soil moisture version v4.5
- Provision of monthly and yearly data products
Among the possibly most relevant changes were (v3.2a versus v3.1a):
- an improved hydrodynamic module
- utilization of MSWEP v2.2 instead of v1.2 for precipitation
- updating the ESA-CCI soil moisture information to v4.3 instead of v2.3.
Department of Forest and Water Management
GHent University, Gent, Belgium
email: brecht.martens (at) ugent.be
ICDC / CEN / University of Hamburg
email: stefan.kern (at) uni-hamburg.de
- GLEAM v3.3 README Document
- GLEAM v3.2 README Document
- GLEAM_v3.1 Datasets README Document
- Miralles, D. G., et al., 2011, Global land-surface evaporation estimated from satellite-based observations. Hydrology and Earth System Sciences, 15, 453-469, doi:10.5194/hess-15-453-2011.
- Miralles, D. G., et al., 2011, Magnitude and variability of land evaporation and its components at the global scale. Hydrology and Earth System Sciences, 15, 967-981, doi:10.5194/hess-15-967-2011.
- Miralles, D. G., et al., 2016, The WACMOS-ET project - Part 2: Evaluation of global terrestrial evaporation data sets, Hydrology and Earth System Sciences, 20, 823-842, doi:10.5194/hess-20-823-2016.
- Martens, B., et al., 2017, GLEAM v3: satellite-based land evaporation and root-zone soil moisture. Geoscientific Model Development, 10, 1903-1925, doi:10.5194/gmd-10-1903-2017.
- Beck, H. E., et al., 2017, MSWEP: 3-hourly 0.25° global gridded precipitation (1979-2015) by merging gauge, satellite and reanalysis data, Hydrology and Earth System Sciences, 21, 589-615, doi:10.5194/hess-21-589-2017.
- Dee, D. P., 2011, The ERA-Interim reanalysis: configuration and performance for the data assimilation system, Quarterly J. Royal Meteorol. Soc., 137, 553-597, doi:10.1002/qj.828.
- Liu, Y. Y., et al., 2011, Global long-term passive microwave satellite-based retrievals of vegetation optical depth, Geophysical Research Letters, 38, L18402, doi:10.1029/2011GL048684.
Upon using this data please cite as follows:
Martens, B., Miralles, D. G., Lievens, H., van der Schalie, R., de Jeu, R. A. M., Fernandez-Prieto, D., Beck, H. E., Dorigo, W. A., and Verhoest, N. E. C., GLEAM v3: satellite-based land evaporation and root-zone soil moisture, Geoscientific Model Development, 10, 1903-1925, doi:10.5194/gmp-10-1903-2017, 2017
Miralles, D. G., Holmes, T. R. H., De Jeu, R. A. M., Gash, J. H., Meesters, A. G. C. A., and Dolman, A. J., Global land-surface evaporation estimates from satellite-based observations, Hydrology and Earth System Sciences, 15, 453-469, doi:10.5194/hess-15-453-2011, 2011
GLEAM v3.3a accessed from www.GLEAM.eu May 8 2019, provided with transposed coordinates as daily files comprising all parameters by the Integrated Climate Data Center (ICDC, icdc.cen.uni-hamburg.de)