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The map shows the mean total precipitation in the month of April. April is a transitional month across much of southern Canada, when snow is still possible but rainfall begins to dominate the precipitation regime. Precipitation amounts across the southern interior of Canada are somewhat greater than those in January, as air temperatures warm in response to the increasing strength and duration of sunshine. Rainfall amounts onshore along British Columbia’s west coast are still in the range of 200 to 300 millimetres, somewhat less than the values in January.

The map shows the annual mean total precipitation. Over much of the continental interior of Canada, precipitation reaches its annual maximum in the summer months and falls as rain. October marks the transition from mainly rain to snowfall across northern Canada.

The map shows the mean total precipitation in the month of October. October marks the transition from mainly rain to snowfall across northern Canada. Snowfall also occurs across much of the interior of southern Canada but in relatively small amounts that usually melt. October also marks the transition to the rainy season on the southern portion of British Columbia’s west coast.

Major ions data consist of the following key ions in precipitation: Cl-, NO3-, SO4=, NH4+, Na+, K+, Ca++, Mg++. The data sets typically also include the pH and depth of the precipitation sample. These data are collected by several provincial, national and bi-national networks. The wet-only precipitation collector samples precipitation only when it rains or snows.

This dataset is part of the International Atomic Energy Agency (IAEA) Global Network of Isotopes in Precipitation (GNIP) project and contains the total monthly precipitation quantity in millimeters collected on the roof of the National Hydrology Research Centre in Saskatoon, SK and its stable oxygen (δ18O) and hydrogen (δ2H) isotope ratios data from June 1990 to January 2020. Up until 2013, a MSC copper rain gauge, modified to hold a HDPE bottle containing a thin layer of paraffin oil to prevent evaporation collected the summer precipitation. Summer precipitation collection from 2013 onward used a Palmex integrator. A plastic 20 L bucket emptied after each snow event collected the winter precipitation until 2015 when we switched to a MSC Nipher shielded snow gauge.

The map shows the mean total precipitation in the month of July. Throughout much of the continental interior of Canada, precipitation reaches its annual maximum in the summer months and falls as rain. On the Prairies, the maximum monthly precipitation is usually in June or July, but this shifts to August at more northerly latitudes and in Ontario and Quebec. On both the west and east coasts, summer is the driest time of the year, particularly on Vancouver Island and the Sunshine Coast of southwestern British Columbia.

Contained within the 3rd Edition (1957) of the Atlas of Canada is a plate that shows two maps for the annual total precipitation. Annual precipitation is defined as the sum of rainfall and the assumed water equivalent of snowfall for a given year. A specific gravity of 0.1 for freshly fallen snow is used, which means that ten inches (25.4 cm) of freshly fallen snow is assumed to be equal to one inch (2.54 cm) of rain. The mean annual total precipitation and snowfall maps on this plate are primarily based on thirty-year data during the period 1921 to 1950 inclusive.

The data represents the annual total precipitation in Alberta over the 30-year period from 1971 to 2000. A 30-year period is used to describe the present climate since it is enough time to filter our short-term fluctuations but is not dominated by any long-term trend in the climate. Annual total precipitation refers to rain, snow and other forms of moisture such as hail. Annual precipitation is greatest in the mountains and decreases at lower elevations.

The Canadian Air and Precipitation Monitoring Network (CAPMoN), operated by Environment and Climate Change Canada (ECCC), is designed to study the regional patterns and trends of atmospheric pollutants such as acid rain, smog, particulate matter and mercury, in both air and precipitation. The network began operating in 1983. CAPMoN updated and replaced two older networks known as the Canadian Network for Sampling Precipitation (CANSAP) and the Air and Precipitation Network (APN). The integration of APN as part of CAPMoN extended the data record as far back as 1978.

The Alberta foothills are a primary source of spring runoff into the prairie regions to the east. For this reason, precipitation accumulations in the foothills are vital to prairie water resources. The Foothills Orographic Precipitation Experiment (FOPEX) was initiated in 2002 to study the dynamics of precipitation and its relationship to elevation in the lee of the Rocky Mountains, including the quantification of processes such as the influence of up-slope (easterly) atmospheric flow on precipitation. Six surface meteorological sites were installed in the Alberta Rocky Mountain foothills between Limestone Mountain and Caroline.