Why is it important for Canada to have a good reliable weather forecast?
Canada is home to the world’s northernmost settlement, Canadian Forces Station Alert, on the northern tip of Ellesmere Island – latitude 82.5°N – which lies 817 kilometres (508 mi) from the North Pole. Much of the Canadian Arctic is covered by ice and permafrost. Canada has the longest coastline in the world, with a total length of 243,042 kilometres (151,019 mi); additionally, its border with the United States is the world’s longest land border, stretching 8,891 kilometres (5,525 mi).
Canada has hosted three Olympic games:the 1976 Summer Olympics in Montreal, the 1988 Winter Olympics in Calgary, and the 2010 Winter Olympics in Vancouver. The World’s longest trail, The Great trail, also goes through Canada.
“Our weather ranges from heavy snowfall, freezing rain or bitterly cold temperatures to heat waves, thunderstorms or tornadoes. Coming from Nunavut, I know from personal experience that a clear day can turn into a blizzard in minutes.”
–Canada’s environment minister
Eight climate zones cover Canada:
There is no doubt Canada should have an accurate weather forecast system.
The climate and weather of Canada has not always been the same as it is now. Geological science is witness that at various times what is now Canada has been submerged under ice. On the other hand, there is evidence that about the year 1000 A.D. the climate of Canada may have been warmer than it is today;
Approximately 700 observing stations have been established, a number of them in the far north; and the records of these stations are published in the Monthly Record of the Meteorological Service of Canada. This periodical, which began, as a two-page issue in 1877, is now a volume of nearly 100 pages. Weather forecasts are now issued twice daily; special warnings of expected gales are telegraphed to agents at more than 100 ports, so that storm signals may be displayed; and special notice is telegraphed to the railways when snowstorms are expected.
— W. Stewart WALLACE, ed., The Encyclopedia of Canada, Vol. IV, Toronto, University Associates of Canada, 1948, 400p., p. 278.
What weather system does Canada have now?
The Meteorological Service of Canada (MSC) is a division of Environment and Climate Change Canada, which primarily provides public meteorological information and weather forecasts and warnings of severe weather and other environmental hazards. MSC also monitors and conducts research on climate, atmospheric science, air quality, water quantities, ice and other environmental issues. MSC operates a network of radio stations throughout Canada transmitting weather and environmental information 24 hours per day called Weatheradio Canada.
Environment and Climate Change Canada, founded in 1971, is the department of the Government of Canada. Its responsibility is to coordinate environmental policies and programs and preserve and enhance the natural environment and renewable resources.
EC‘s monitoring infrastructure includes 31 weather radars, 84 lightning detection sensors, 125 fixed buoys and automatic marine stations installed on ships, 31 stations for launching balloon-borne observations of the upper atmosphere, satellite data, and about 1,200 surface weather and climate stations.
Here are the major forecast models used by weather services:
- Global Forecast System (GFS)
- Integrated Forecast System (IFS)
- The Global Environmental Multiscale Model (GEM)
- Mesoscale models.
- Ensemble Forecasts
The Global Forecast System (GFS) is a global numerical weather prediction computer model run by NOAA. The model has two parts which run for eight days (high resolution) and 16 days (low-resolution).
The Integrated Forecast System (IFS), an operational global meteorological forecasting model, is developed and maintained by the European Centre for Medium-Range Weather Forecasts (ECMWF) based in Reading, England.
The Global Environmental Multiscale Model (GEM) is integrated forecasting and data assimilation system developed in the Recherche en Prévision Numérique (RPN), Meteorological Research Branch (MRB), and the Canadian Meteorological Centre (CMC). It has been developed to meet all of Canada’s current and foreseeable operational weather-forecasting needs for the coming years.
What differentiates these models from each other, and how good is their forecast?
There are four types of models: grid point, spectral, hydrostatic, and non-hydrostatic. All models use primitive equations to predict the weather. This is a set of nonlinear differential equations that are used to approximate global atmospheric flow and are used in most atmospheric models:
There are three main laws behind them:
- Continuum equation (conservation of mass), which describes the transport of some quantity.
- Conservation of momentum
- Conservation of energy
Forces that cause atmospheric motion include the pressure gradient force, gravity, and viscous friction. So, most forecasts of surface conditions, such as temperature and precipitation, are generated by computer models which assimilate surface pressure and upper-air height data with tropospheric temperature, moisture, and wind conditions. The present limit of deterministic weather predictability is a few weeks at most. The major limiting factors are incomplete knowledge of the atmosphere’s initial state and imperfect understanding of atmospheric processes. The first factor is most important at short lead times, while modeling errors become the dominant limitation in longer forecasts.
An assessment by the American Meteorological Society attributed considerable skill to short-range (12± 72 hours) forecasts, with skill decreasing in the medium range (3± 7 days) from good at 3 days to marginal at 7, with, in some cases, measurable skill persisting out to 10 days.
Forecast skill is determined as follows, where the perfect forecast is equal to one:
Another measure of the model forecast is “anomaly correlation,” a measure of its ability to accurately predict observations (a score of 1 is perfect). For the northern hemisphere during the last two months, as measured at the 500mb level of the atmosphere (about 5.5km above the Earth’s surface), the European model scores the highest by far, at .905. It’s followed by the United Kingdom’s model (.870), the Canadian model (.868), and finally the GFS (.857).
By anomaly correlation score, the Canadian global model takes third place after ECMWF and UKM.
Here are some interesting thoughts on model forecast accuracy.
The other factors affecting the model’s accuracy are initialization data, bugs and model biases, and computer power.
According to CBC News, in December 2015, Environment Canada got a new supercomputer. So more accurate forecasts should help people prepare for emergencies and boost the Canadian economy by providing everyone from farmers and fishermen to truck drivers and emergency workers with more reliable information.
Overall Canadian weather service provides quite a good and reliable weather forecast. You can view the radar data here.
According to Weather, vol.57, 2002:
Short- and medium-range forecasts of minimum and maximum temperature issued by the MSC show skill even out to five days in some cases. Skills are highest for maximum temperatures and for sites in the interior of the country where scores above 60% were noted. The coastal stations have lower forecast errors than inland sites but, because of much lower temperature variability, their skill scores are the lowest in the country, and are almost negligible at Vancouver after 2±3 days. Precipitation forecasts of dry weather are generally more successful than those of wet weather, achieving 100% accuracy for Days 1 and 2 at Vancouver. This compares to about 40% for wet weather at Banff. Only the most continental sites (Kapuskasing and Saskatoon) show variations in accuracy with lead time.