La série d'ensembles de données « Ruissellement unitaire annuel au Canada selon AAC - 2013 » présente les tendances du ruissellement dans l'ensemble du pays au moyen d'isolignes du ruissellement unitaire annuel pour diverses probabilités de dépassement communément utilisées par les décideurs. Le ruissellement unitaire annuel est une mesure du volume d'eau de ruissellement par kilomètre carré. L'unité utilisée dans cette série d'ensembles de données est le décamètre cube (1000 m3) par kilomètre carré (dam3/km2), qui équivaut à une hauteur de précipitation de un millimètre sur le paysage. La série comprend un ensemble de données ponctuelles concernant les stations hydrométriques utilisées pour l'analyse du ruissellement unitaire, et sept ensembles de données présentant les isolignes ajustées pour les probabilités de dépassement de 10 %, 25 %, 50 %, 70 %, 75 %, 80 % et 90 %. Pour plus d'information, consulter : http://ouvert.canada.ca/data/fr/dataset/a905bafc-74b5-4ec5-b5f9-94b2e19815d0

The “Annual Unit Runoff (dam3/km2) for a 10% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 10% Probability of exceedence annual unit runoff.

The “Annual Unit Runoff (dam3/km2) for a 70% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 70% Probability of exceedence annual unit runoff.

The “Annual Unit Runoff (dam3/km2) for a 90% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 90% Probability of exceedence annual unit runoff.

The “Annual Unit Runoff (dam3/km2) for a 25% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 25% Probability of exceedence annual unit runoff.

The “Annual Unit Runoff (dam3/km2) for a 75% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 75% Probability of exceedence annual unit runoff.

The “Annual Unit Runoff (dam3/km2) for a 50% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 50% Probability of exceedence annual unit runoff.

The “Annual Unit Runoff (dam3/km2) for a 80% Probability of Exceedence” dataset is a line data set that covers the extent of Canada. It shows the 80% Probability of exceedence annual unit runoff.

The “Stations used for Unit Runoff Analysis” dataset is a point data set for select hydrological stations that covers the extent of Canada.

The “Hydrometric Gauging Station Network of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing network line features representing links between hydrometric gauging stations of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. Each line connects a gauging station to its downstream neighbour(s), indicating its drainage direction. This network is a ‘drainage’ network, not a ‘stream’ network. That is, the lines do not in any way portray the actual stream path between stations. In some instances, a lake, for example, an area may have several gauging stations. In such cases, one of the gauging stations is designated the ‘primary’ gauging station for calculation purposes, and to maintain proper hydraulic relationships between gauging stations, where only the primary stations are connected to the downstream portion of the network.