Vegetation Drought Response Index

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The following maps and data show where vegetation is stressed due to dry conditions and excessive moisture. The information depicts a modeled plant response to environmental conditions generated from climate-based drought indicators, satellite-derived vegetation conditions, and environmental data.

Map updated for the most recent conditions

Description – Legend

The map shows modeled plant response ratings from exceptional drought at the extreme dry end of the scale to extreme moist on the extremely wet end of the scale.

  • Dark red: Exceptional drought
  • Red: Extreme drought
  • Orange: Severe drought
  • Yellow: Moderate drought
  • Light yellow: Pre-drought stress
  • White: Near normal
  • Light green: Unusually moist
  • Green: Very moist
  • Dark green: Extreme moist

Vegetation Drought Response Index (VegDRI) data

Browse through the VegDRI data (Open Data) which represents the dryness of the land surface based on vegetation conditions.

About the Vegetation Drought Response Index maps

VegDRI models vegetation stress related to dry conditions across the agricultural regions of Canada. The model relies on three main inputs, measured on a weekly basis – the percent Average Seasonal Greenness (PASG), Start of Season Anomaly (SOSA), and a rolling 36-week Standard Precipitation Index (SPI). PASG and SOSA are calculated from the normalized difference vegetation index (NDVI) data acquired by NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) sensors. The SPI data is captured using weather stations across Canada, and calculated using quality controlled data from AAFC. VegDRI also incorporates information about elevation, soil types, and ecoregions into the model to provide regional calibration of the model output.

VegDRI was developed by researchers at the National Drought Mitigation Center of University Lincoln Nebraska, and has been adapted for Canada in collaboration with researchers at Agriculture and Agri-Food Canada.

Additional information

More information on VegDRI can be found on the US National Drought Mitigation Center website.