Standardized Precipitation Index (SPI)

The Standardized Precipitation Index (SPI) has been recognized as the most accessible index for quantifying and reporting meteorological drought. On short timescales, the SPI is closely related to soil moisture, while at longer timescales, the SPI can be related to groundwater and reservoir storage. The model uses observed historical precipitation amounts to compute probability distributions which are then normalized using an incomplete gamma function over a range of timescales. The values can be interpreted as the number of standard deviations by which the observed anomaly deviates from the long-term mean. where positive values (greater than zero) result from above average conditions.

Données et ressources

Info additionnelle

Champ	Valeur
Dernière modification	avril 17, 2026, 18:43 (TU)
Créé le	avril 17, 2026, 18:43 (TU)
contact_email	agri-geomatics-agrog@agr.gc.ca
contact_person	{"en": "Government of Canada; Agriculture and Agri-Food Canada; Science and Technology Branch,agri-geomatics-agrog@agr.gc.ca", "fr": "Gouvernement du Canada; Agriculture et Agroalimentaire Canada; Direction générale de la science et de la technologie,agri-geomatics-agrog@agr.gc.ca"}
criticality_level	[]
data_dictionary	EPSG:3857,http://www.epsg.org/,8.3.4
geographic_scope	[]
open_canada_collection	fgp
open_canada_date_published	2017-05-05 00:00:00
open_canada_keywords	{"en": ["SPI", "agclimate", "Farmlands", "Precipitation", "Temperature", "Crops", "Agriculture"], "fr": ["SPI", "agclimat", "Terre agricole", "Précipitation", "Température", "Cultures", "Agriculture"]}
open_canada_subject	["nature_and_environment", "science_and_technology"]
sensitivity_level	unrestricted
title_fr	Indice normalisé des précipitations (INP)
update_frequency	as_needed