Woody and Herbaceous Vegetation Change across the Savannas of West Africa, 1982-2013

The WAVeTrends dataset is a 0.05 degree (5.55 km) vegetation change product, spanning the West African Sudano-Sahel region. It provides pixel-wise information on concurrent woody and herbaceous vegetation trends over a 32-year period (1982-2013). Change in woody vegetation was derived using long-term rain use efficiency (RUE) sensitivity, i.e., the per-pixel comparison of the difference of mean RUE between the first and last decades of the 32-year time series. Herbaceous vegetation change was defined by short-term RUE sensitivity, i.e., comparing the slope of the RUE relationship (productivity vs. precipitation) between both decades using per-pixel Analysis of Covariance (ANCOVA). Categorical vegetation change was then determined for each pixel using the direction of the change and a significance level of p<0.05. The use of RUE (the amount of biomass produced per unit of precipitation) for vegetation trend analysis in savanna regions relies on the assumption that rainfall is a significant positive driver of net production in drylands. Testing of this long-term productivity-rainfall relationship revealed that the assumption was not always met, therefore, validity flags are included for each pixel location.

Data and Resources

Additional Info

Field Value
Maintainer Earthdata Forum
Last Updated March 10, 2026, 04:20 (UTC)
Created April 1, 2025, 20:03 (UTC)
accessLevel public
bureauCode {026:00}
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
harvest_object_id 460f575c-d1d3-473a-ad3b-4a810fc21324
harvest_source_id b99e41c6-fe79-4c19-bbc3-9b6c8111bfac
harvest_source_title Science Discovery Engine
identifier 10.3334/ORNLDAAC/1738
license https://www.usa.gov/government-works
modified 2026-03-05T23:29:36Z
programCode {026:000}
publisher ORNL_DAAC
resource-type Dataset
source_datajson_identifier true
source_hash 1b8605e60358f7d7ef3adf4a626bd7e38bd0eff11aaf700874e103fe3fc7a374
source_schema_version 1.1
spatial [[{"WestBoundingCoordinate":-17.1432,"NorthBoundingCoordinate":17.4148,"EastBoundingCoordinate":15.3068,"SouthBoundingCoordinate":9.96476}],"CARTESIAN"]
temporal 1982-01-01/2013-12-31
theme {"Earth Science"}