Global 500m Evapotranspiration and Latent Heat Flux 8-Day Composites

Eight-day composite global data layers for evapotranspiration (ET), latent heat flux (LE), and their potential counterparts, produced at a 500-meter pixel resolution. The dataset is generated by NASA using the MODIS sensor on the Terra satellite and an algorithm based on the Penman-Monteith equation, incorporating meteorological reanalysis and MODIS land products. Its availability on multiple major data platforms indicates established use and reliability.

Use Cases

• Modeling regional water budgets by analyzing the 8-day sum of evapotranspiration (ET) values.
• Assessing surface energy balance using the average latent heat flux (LE) layer.
• Estimating irrigation demand and crop water stress by comparing actual ET to potential ET (PET).
• Monitoring drought conditions through temporal analysis of evapotranspiration anomalies.
• Validating land surface models using the quality control layer to filter data reliability.

Strengths

• Provides a long-term, consistent global record with an 8-day composite frequency, enabling trend analysis.
• Uses a physically-based algorithm (Penman-Monteith) integrating multiple MODIS products and meteorological data.
• Version 6.1 includes specific calibration improvements for the 2012-2017 period, enhancing data accuracy.
• Cross-platform presence on NASA Earthdata, AWS Open Data, and Data.gov signals wide adoption and importance.

Limitations

• Pixel resolution is 500m, which may be too coarse for field-scale or detailed watershed studies.
• Sources conflict on the license, with one listing CC-BY-4.0 and another 'other-license-specified', requiring user verification.
• The last composite period of each year is only 5 or 6 days, creating a temporal inconsistency in annual sums.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Remote sensing data from the MODIS/Terra sensor, processed using the Penman-Monteith algorithm with inputs from daily meteorological reanalysis and other MODIS products.

Time Range

2000 to present (implied by MODIS Terra mission lifetime and version updates covering 2012-2017).

Freshness

2026-03-13 00:12:33.362848

Geography

Global