Dry Midlatitude Climates (Bs)

There are many types of grasslands around the world. Some of the grasslands are tropical and some are dry grasslands. Grasslands in North America are known as Prairies, and in South America they are known as the Pampas. Eurasia has the Steppes, and in South Africa they are called Savanna and Veldt.

The prairies of the midwestern United States are both tall-grass and short-grass. West of the Mississippi River the temperature is moist and humid. This allows for some very tall grasses of up to 10 feet. Summers are warm and humid. Winters are cold but not to the extreme. The farther west and in the interior of the country, the temperatures becomes drier. Moisture from the Pacific Ocean is blocked by the mountains. This is where the short-grass prairies are found. Summers are hot and winters very cold. There are no natural barriers, like trees, so there is a constant wind. Grasses with deep root systems keep the soil from blowing away. Most animals have adapted to the open, treeless prairie by digging burrows. Even owls, like the Burrowing Owl, use the holes dug by prairie dogs as nesting sites. The mean temperatures for the prairie in January is 20° F, and 70° F in July. Annual precipitation is 10-30 inches.

The Savanna is a tropical grassland in Africa. This grassland has a very hot, wet season when warm, moist air from the equator moves in. This is followed by a cooler dry season that can last for 8 months or more. Hot, dry air moves in from the Sahara. It is cooler by a few degrees Celsius because there is no moisture to trap the sun's radiant energy, and most of the heat escapes into space again. The Veldt is in South Africa and is pretty much like a savanna, except in the southern hemisphere.

Another southern hemisphere grassland is the Pampas of Argentina. Moist, tropical air dominates this area and there is a lot of rain. Here tall-grass varieties of grasses grow very well.

The Steppes have a cold, dry climate. Here you find short-grass type of plants. The Himalayas block warm, moist air from the Indian Ocean, so there is very little precipitation. Nothing blocks arctic winds though, so winters are very cold and windy.

The grassland biome climate is in a mid-latitude zone. It is classified as a type "B" category, with a "Bs" subtype climate under the Köppen classification system. The grasslands have a very large latitude range, spanning from 55° N to 30° S. This is because of the many different types of grasslands throughout the world. The grasslands are on every continent, except for Antarctica.

by Emma K. 2000.



The Book of Knowledge, -P- volume 15. Danbury, CT. Grolier Inc.

Encarta 1994, Microsoft Corporation

"Köppen's Climate Classifications System", http://www.tesarta.com/www/resources/library/biomes.html, (June 5, 2000).

"Biomes Information Page", http://www.rochester.k12.mn.us/kellogg/orange/bioinfo.html, (June 3, 2000).