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Found 10 records similar to Mean maximum depth of snow and time of occurrence
Contained within the 5th Edition (1978 to 1995) of the National Atlas of Canada is a plate with seven maps. The first map shows mean annual snowfall in Canada. Four additional maps show median snow depth for four separate months. The final two maps show snow cover and maximum snow depth.
Contained within the 3rd Edition (1957) of the Atlas of Canada is a map that shows the snow cover data, referring primarily to the presence and total depth of a snow cover on the surface of the earth, across Canada. This is in contrast to data characteristics of snow cover depth, which increases by the occurrence of freshly fallen snow, but decreases by melting, wind action and settling. Two maps of these maps show the mean dates of the occurrence of first and last snow covers by one inch (2.54 cm) or greater. These are not necessarily the average dates to the beginning and ending of a continuous snow cover, since the snow cover may form and later disappear once or several times during a winter season.
Over southern Canada maximum snow depth usually occurs in January or February, while the time of maximum accumulation occurs much later in mountain areas and in the Arctic. The main features of the map are the pronounced maximum in snow accumulation over the western Cordillera (British Columbia and Yukon), where snow depths can exceed several metres, with a secondary maximum over Quebec and Labrador. These maxima are related to their proximity to oceans, which acts as sources of moisture and winter storms, and to the orographic effect of the mountains in the case of western Canada. The two maxima are linked by a band of higher snow accumulation that follows the boreal forest zone; this is a preferred track for winter storms.
This map shows the average maximum snow depth in centimetres computed over 18 winter seasons (1979 to 1997). Over southern Canada this usually occurs in January or February, while the time of maximum accumulation occurs much later in mountain areas and in the Arctic. The main features of the map are the pronounced maximum in snow accumulation over the western Cordillera, where snow depths can exceed several metres, with a secondary maximum over Quebec and Labrador. These maxima are related to their proximity to oceans, which act as sources of moisture and winter storms, and to the orographic effect of the mountains in the case of western Canada.
The map shows isolines on four different dates: 1) the day of the year when there are less than or equal to 2.5 centimetres of snow that occurs and remain absent for 7 or more days; 2) the standard deviation of the mean date of snow cover loss; 3) the day of year when greater than or equal to 2.5 centimetres of snow occur and remain for more than 7 days; and 4) the standard deviation of the mean date of snow cover formation. The beginning and end of the winter season in Canada is usually identified with the formation and disappearance of snow cover in autumn and spring respectively. The duration of snow cover varies considerably from year to year in the southern fringes of the country and adjacent to the east and west coasts. However, even in northern continental areas early and late snowfalls which leave an ephemeral snow cover are common.
This dataset corresponds to daily snow cover percentage at 1km resolution grid over land areas of Canada from 2006-2010. The data are subsampled by 4km to reduce data volumes and considering the geolocation uncertainty of the input satellite imagery. The daily maps are generated by assimilation of daily cloud screened NOAA AVHRR satellite imagery and Canadian Meteorological Centre (CMC) snow depth analysis snow depth and density fields within an off-line version of the CMC daily snow depth model. The snow depth model is modified to include snowpack reflectance model and a surface radiative transfer scheme that relates vegetation and snowpack reflectance to top-of-canopy bi-directional reflectance.
The map shows the annual snowfall (in centimetres) based on the 30-year period 1941-1970. Snowfall is measured by inserting a ruler into the new snow at several points to obtain its depth and to estimate the degree of drifting or scouring that has occurred. The water equivalent of snowfall for most climatologically stations is estimated by simply assuming the freshly fallen snow has a density of 0.10 gram per cubic centimetre. On the average, this is a sound approximation over large parts of the country, but variations from 0.05 to 0.15 are common from storm to storm, and in the drier regions the average density is probably closer to 0.08 gram per cubic centimetre.
This measure is based on snow-tracking data from established snow-transects. Trends for this metric focus on wary carnivores (cougar, lynx, wolf, and wolverine) on transects within 5 km of the Townsite. Data collected include location, species presence, number of animals, hours since snow, & snow-depth.
The measure is based on snow-tracking data from 3 established snow-transects in the Kicking Horse Valley. Trends for this metric focus on wary carnivores (cougar, lynx, wolf, and wolverine) though prey (ungulate) data will also be collected. Data collected include location, species presence, number, days since snow, & snow-depth.
This dataset includes historical observations of the daily depth of snow on the ground (daily climate element 013) made at Environment and Climate Change Canada (ECCC) sites by manual ruler or by a sonic sensor equipped autostations. The history of the ECCC daily snow depth observing program is provided in Brown et al. (2021) along with a detailed intercomparison of ruler and sonic sensor observations that showed manual observations typically reporting more snow than a nearby sonic sensor. The database includes a measurement method flag to differentiate between the two methods.