Canadian Drought Monitor

This series of datasets has been created by AAFC’s National Agroclimate Information Service (NAIS) of the Agro-Climate, Geomatics and Earth Observations (ACGEO) Division of the Science and Technology Branch.
The Canadian Drought Monitor (CDM) is a composite product developed from a wide assortment of information such as the Normalized Difference Vegetation Index (NDVI), streamflow values, Palmer Drought Index, and drought indicators used by the agriculture, forest and water management sectors. Drought prone regions are analyzed based on precipitation, temperature, drought model index maps, and climate data and are interpreted by federal, provincial and academic scientists.
Once a consensus is reached, a monthly map showing drought designations for Canada is digitized.
AAFC’s National Agroclimate Information Service (NAIS) updates this dataset on a monthly basis, usually by the 10th of every month to correspond to the end of the previous month, and subsequent Canadian input into the larger North American Drought Monitor (NA-DM).
The drought areas are classified as follows:

D0 (Abnormally Dry) – represents an event that occurs once every 3-5 years;
D1 (Moderate Drought) – represents an event that occurs every 5-10 years;
D2 (Severe Drought) – represents an event that occurs every 10-20 years;
D3 (Extreme Drought) – represents an event that occurs every 20-25 years; and
D4 (Exceptional Drought) – represents an event that occurs every 50 years.

Impact lines highlight areas that have been physically impacted by drought.
Impact labels specify the longitude and magnitude of impacts.
The impact labels are classified as follows:
S – Short-Term, typically less than 6 months (e.g. agriculture, grasslands).
L – Long-Term, typically more than 6 months (e.g. hydrology, ecology).