Browse "Climate"

Thunderstorms usually occur on summer afternoons. While a thunderstorm typically affects a given locality for only an hour or so during its passage overhead, the entire lifetime may be as long as 6-10 hours, along a pathway of several hundred kilometres.

The official time reference for Canada comes from the National Research Council of Canada (NRC), but, with the exception of during wartime, the provinces and municipalities legislate the official time zone boundaries.

The treeline is controlled by CLIMATE in interaction with SOIL. In the North, it is correlated generally with the modal (most common) position of the southern edge of the arctic front in summer, and with such temperature indices as the July 10°C isotherm.

​Vegetation regions are geographical areas characterized by distinct plant communities.

WEATHER FORECASTING is the attempt to understand atmospheric patterns to predict the weather conditions that will occur at a specific place and time, including temperature, wind, cloud, precipitation and humidity.

Most modern meteorologists attempt to cope with physical processes by expressing them mathematically, ie, by creating mathematical models of the atmosphere. Powerful computers are then used to solve problems.

Weather modification has been used in an attempt to increase rainfall and snowfall, to suppress hail, to clear fogs, to modify tropical cyclones and to suppress lightning. The term "weather modification" is not normally used to describe inadvertent changes in our WEATHER.

   Weather in Canada ranges from the extreme cold of the Arctic to tornadoes and other severe weather in the southern regions; from the storms and fog of the Atlantic to the dry heat and majestic thunderstorms of the prairies.

In the atmosphere, between about 1.2 and 1.6 km above the Earth's surface, winds tend to blow parallel to rather than across the lines of equal pressure (isobars).

Winter occurs as the Earth's axis tilts away from the sun during the planet's annual rotation. The portion of the Earth that is furthest from the sun experiences winter, with weather that is colder than the other seasons. In the Northern Hemisphere, winter officially begins with the winter solstice, around 21 December, and ends at the spring equinox, around 21 March. Winter figures largely in Canada's climate, cultural experience and mythology. Every aspect of life in Canada is affected by winter, whether by heavy rains on the West Coast, isolation during the long Arctic winters, raging blizzards across the prairies or huge snowfalls in eastern Canada. Winter is reflected in Canadian art, literature, music, fashion, pastimes and attitudes.

About 30 minutes in length, the work has three movements: I The Darkest Hour, II Simulacrum, III The Prophet of Light. Hatzis explains that the title refers to the spiritual meaning of the "longest night" and that the work "...is a meditation on our own times ...