Evaporation parameters from GLEAM

GLEAM Actual evaporation January 2016 — GLEAM Actual evaporation July 2023, Copyright: UHH/CEN/S. Kern.

Topics

Access

RESTRICTED: This link to the data set is only available for a restricted user group. The data set is only accessible in CEN/MPI net or accessible from external nets with a customer account. Please contact ICDC if you would like to access this data from outside the network.

View evaporation data at LAS
Access evaporation data via OPeNDAP
Data access via file system: /data/icdc/land/gleam_evaporation

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Description

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 v4.1a. The other product, v4.1b, covers basically the observation period of MODIS, and is available via the GLEAM Website (see references).

Last update of data set at ICDC: August 22, 2024.

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Parameters

Parameters of the evaporation data set
Name	Unit	Comment
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
Surface condensation	mm / day or month
Evaporative stress (factor)	-	Range: 0 ... 1
Sensible heat flux at surface	W / m2
Root-zone soil moisture	m3 / m3
Near-surface soil moisture	m3 / m3	0 ... 10 cm depth

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Coverage, spatial and temporal resolution

Period and temporal resolution:

Daily: 1980-01-01 to 2023-12-31
Monthly: 1980-01 to 2023-12

Coverage and spatial resolution:

Global
Spatial resolution: 0.1° x 0.1°, Climate modeling grid
Geographic longitude: 179.95°W to 179.95°E
Geographic latitude: 89.95°S to 89.95°N
Dimension: 1800 rows x 3600 columns
Altitude: following terrain

Format:

NetCDF

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Data quality

This data set does not contain any uncertainty information.

Details about the accuracy and the representativity of the data sets can be found at the GLEAM Website and in the Readme document (see references). The Readme document includes a list of relevant publications which is more extensive than the list here in the references, it shows an overview about the input data sets in Table 1,

and information about the most relevant changes compared to version v3.3 and version v3.2.

For the most relevant changes between v4.1a and v3.7a (and earlier versions) we refer to the README documents under references.

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Contact

Brecht Martens
Department of Forest and Water Management
GHent University, Gent, Belgium
email: brecht.martens (at) ugent.be

Stefan Kern
University of Hamburg
E-Mail: stefan.kern (at) uni-hamburg.de

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References

Literature:

GLEAM Readme Document v4.1 (pdf, not barrier free)
GLEAM Readme Document v3.7 (pdf, not barrier free)
GLEAM Readme Document v3.6 (pdf, not barrier free)
GLEAM Readme Document v3.5 (pdf, not barrier free)
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.

Websites:

Global Land Evaporation Amsterdam Model (GLEAM) Website, http://www.gleam.eu

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Data citation

Please cite the data 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

and

GLEAM v4.1a , last accessed from www.GLEAM.eu on August 14 2024, provided as daily / monthly files comprising all parameters by the Integrated Climate Data Center (ICDC), CEN, University of Hamburg.

and with the following acknowledgments:

Thanks to ICDC, CEN, University of Hamburg for data support.

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