Module #20 - Climate Zones & Influence on Climate
INSTRUCTIONS FOR TODAY
1. Watch the following video: Video of the Day: New Thinking on the Climate Change Crisis (28 minutes)
Be sure to make point form notes from this video in your digital video journal. Please make sure this document is SHARED with Mr. Durk.
2. Read the following information below in Part 1: Background and Terminology. Follow all hyper-links to external websites for activities, demonstrations and videos (if applicable). Copy only KEY information (i.e. the highlighted terms) to your digital notebook (in google docs). Mr. Durk will be doing a
3. Part 2: Climate Graph Exercise (complete the hard copy that Mr. Durk provides to you or print out from this site)
4. Part 3: Quiz #5. Please complete this quiz between 11:00 - 11:45 am today using the LMS site.
DUE DATE: Submit all components to Mr. Durk via the UG Cloud before Module #21 (Friday June 3rd) - QUIZ must be completed during today's class period.
Content
Please remember to record all definitions in your virtual notebook. Definitions can be found by clicking on highlighted words.
Climate Zones
The world is divided into different climate regions based on their temperature and amount of precipitation. The most commonly used classification system was developed by Wladimir Köppen, a German climatologist, around 1900.
Use the following link for a better view of the above map. Koppen Climate Map
Köppen climate classification scheme divides the climates into five main groups and several types and subtypes. Each particular climate type is represented by a 2 to 4 letter symbol.
GROUP A: Tropical/Megathermal climates
Tropical climates are characterized by constant high temperature (at sea level and low elevations) — all twelve months of the year have average temperatures of 18 °C (64.4 °F) or higher. This group is also subdivided into: tropical rainforest (Af), tropical monsoon (Am) and tropical wet and dry (Aw).
GROUP B: Dry (Arid and semiarid) climates
These climates are characterized by the fact that precipitation is less than potential evapotranspiration. This means that there is more moisture being evaporated than is being created. If the annual precipitation is less than half the threshold for Group B, it is classified as BW (desert climate); if it is less than the threshold but more than half the threshold, it is classified as BS ( steppe climate). A third letter can be included to indicate temperature. When the coldest month has an average temperature that is above 0 °C, h is used. k is used to denote that at least one month averages below 0 °C. On occasion, a fourth letter is added to indicate if either the winter (w) or summer (s) is "wetter" than the other half of the year.
GROUP C: Temperate/mesothermal climates
These climates have an average temperature above 10 °C in their warmest months, and a coldest month average between -3 °C and 8 °C. The second letter in the classification system indicates the precipitation pattern — w indicates dry winters, s indicates dry summers and f means significant precipitation in all seasons (neither above mentioned set of conditions fulfilled). The third letter indicates the degree of summer heat — a indicates warmest month average temperature above 22 °C, b indicates warmest month average temperature below 22 °C, while c means 3 or fewer months with mean temperatures above 10 °C. This group is further divided into four categories: mediterranean, humid subtropical, maritime temperate and maritime subarctic.
GROUP D: Continental/microthermal climate
These climates have an average temperature above 10 °C in their warmest months, and a coldest month average below -3 °C. The second and third letters are the same as used in Group C climates, while a third letter of d indicates 3 or fewer months with mean temperatures above 10 °C and a coldest month temperature below -38 °C. This group is further subdivided as follows: hot summer continental, warm summer continental, continental subarctic (taiga), continental subarctic with severe winters.
GROUP E: Polar climates
These climates are characterized by average temperatures below 10 °C in all twelve months of the year. This group is subdivided into two categories. Tundra climate (ET) has a warmest month has an average temperature between 0 °C and 10 °C. Ice Cap climate (EF) has all twelve months averaging temperatures below 0 °C.
Climate Patterns
As stated in the previous activity, climate patterns are dictated by many factors. We will look at those specific climate patterns that are common to Canada. These include: steppe (Bs), marine west coast (Cfc), continental (Dfa, Dfb), subarctic (Dfc) and arctic (Et).
A steppe pronounced in English as step, is a plain without trees (apart from those near rivers and lakes); it is similar to a prairie, although a prairie is generally considered as being dominated by tall grasses, while short grasses are said to be the norm in the steppe. It may be semi- desert, or covered with grass or shrubs, or both depending on the season and latitude. The climate of mid-latitude steppes can be summarized by hot summers and cold winters, averaging 250-500 mm of rain or equivalent in snowfall per year. Three grassland types occur in the Canadian prairies: tallgrass prairie, mixed prairie, and fescue prairie. Each has a unique geographic distribution and characteristic mix of plant species.
This is the climate typically found along the west coasts at the middle latitudes of all the world's continents. Marine West Coast climates are characterized by a narrower annual range of temperatures than are encountered in other places at comparable latitudes. This means that precipitation is both adequate and reliable at all times of the year in West Coast climates. The West Coast climate of Canada is specifically influenced by the Coast Mountains as well. This mountain chain causes increased precipitation to the area because of the mountains relief.
Temperatures in Vancouver rarely go below -10 °C . Victoria has an even milder climate with no temperatures below 10 °C since 1996. Due to the high precipitation in this area of Canada, it contains some of the world’s largest temperate rainforest’s.
A continental climate is the climate typical of the middle-latitude interiors of the large continents of the Northern Hemisphere in the zone of westerly winds. This climate is characterized by winter temperatures cold enough to support a fixed period of stable snow cover each year, and relatively low precipitation occurring mostly in summer, although east coast areas (chiefly in North America) may show an even distribution of precipitation. These regions generally have either forest or tall-grass prairie as natural ground covers, and include some of the most productive farmlands in the world. All such climates have at least three months of temperatures in excess of 10°C and winters with at least one month below 0°C. Continental climates exist where cold air masses infiltrate during the winter and warm air masses form in summer under conditions of high sun and long days. Places with continental climates are as a rule either far from any moderating effects of oceans ( Regina, Saskatchewan) or are so situated ( Halifax, Nova Scotia) that prevailing winds tend to head offshore. Such regions get quite warm in the summer, achieving temperatures characteristic of tropical climates but are much colder than any other climates of similar latitude in the winter.
Regions having a subarctic climate (also called boreal climate) are characterized by long, usually very cold winters, and brief, warm summers. They are found on large landmasses, away from the moderating effects of an ocean, generally at latitudes from 50° to 70°N. This type of climate offers some of the most extreme seasonal temperature variations found on the planet: In winter, temperature can drop to −40°C and in summer, the temperature may exceed 30°C. However, the summers are short; no more than three months of the year (but at least one month) must have a 24-hour average temperature of at least 10°C to fall into such climate. The subarctic climate is a subset of the continental climate. With 5-7 consecutive months where the average temperature is below freezing, all moisture in the soil and subsoil freezes solidly to depths of many feet. Summer warmth is insufficient to thaw more than a few surface feet, so permafrost prevails under large areas.
Tundra climates have at least one month that has an average temperature high enough to melt snow (0°C), but no month with an average temperature in excess of (10°C). The cold limit generally meets the EF climates of permanent ice and snows; the warm-summer limit generally corresponds with the poleward or altitudinal limit of trees, where they grade into the subarctic climates. Tundra climates as a rule are hostile to woody vegetation even where the winters are comparatively mild by polar standards, as in Iceland.
Despite the potential diversity of climates in the arctic category involving precipitation, extreme temperatures, and relative wet and dry seasons, this category is rarely subdivided. Rainfall and snowfall are generally slight due to the limited capacity of the chilly atmosphere to hold water vapor, but as a rule potential evapotranspiration is extremely low, allowing soggy terrain of swamps and bogs even in places that get precipitation typical of deserts of lower and middle latitudes. Scarcity of lushness (by polar standards) of native vegetation of tundra regions depends more upon the severity of the temperatures than upon the scarcity or copiousness of precipitation.
The following interactive object will provide a review of the content for this activity and allow you to plot a Climate graph. Click here to begin.