Flashcards in Climates and natural regions Deck (19):
What is a climate?
A climate is the average weather conditions over a long period of timel Usually 30/40 years.
Factors influencing world climates.
Latitude, prevailing wind and distance from the sea.
Factors influencing world climates - latitude
The sun's rays hit the surface of the earth more directly at the equator and at more of an angle the further north and south of the equator.
Factors influencing world climates - prevailing wind
The wind influences the amount of precipitation and temperature a place receives. The wind direction varies and so can weather. Eg, south-westerlies.
Factors influencing world climates - distance from the sea
Sea heats more slowly than land during summer. The sea takes longer to lose it's heat during winter. The further away from the sea, the warmer the summers and colder the winters. (Conventional climates.)
Characteristics of a hot desert climate.
Daytime temperatures are high, 30*C to 50*C.
Hot deserts are located in the tropics, where the sun is always high in the sky.
Cloudless skies allow for long hours of sunshine.
-Night-time temperatures as low as 5*C.
The absence of cloud cover + vegetation leads to rapid loss of heat at night.
Night = 'Winter of the Desert'
-Large daily temperature range.
Rainfall is rare. Annual total is less than 100mm. There are long periods of drought broken by sudden downpours.
Deserts are in the path of trade winds. These blow overland towards the equator, making them warmer and hold their moisture. Result: dry winds.
Some deserts are in the path of winds blowing over cold currents. These winds get cooled and lose their moisture over the ocean.
Vegetations in hot deserts.
-Little vegetation because of shortage of moisture.
-Plants have survived by adapting to desert conditions.
-Cacti have thick waxy skin to hold moisture and have roots that spread out to absorb water.
-The date palm have taptroots that grow deep into the ground to find moisture.
Animals in hot deserts.
Animals have adapted to the harsh desert climate.
-camels, foxes and rattlesnakes have adapted to the conditions of intense heat and lack of moisture.
-foxes hide underground where it is cool during the day and come out at night.
-Rattlesnakes absorb moisture from what they eat.
Desertification - what is it?
Desertification is the turning of fertile land into deserts.
Results of desertification.
Many people have died as a result of famine. Eg, Sudan and Ethiopia.
Many people moved into urban areas, leading to the growth of slums.
Millions of animals have died.
Solutions to desertification.
Slow down soil erosion by planting trees as shelter belts.
Bind the soil particles by planting grasses which are resistant to drought.
Dig deeper wells to find water for irrigation.
Characteristics of a warm temperate climate.
Summers are hot with temperatures averaging 30*C.
These regions are close to the equator. Sun is still high in the sky.
Cloudless skies allow for long hours of sunshine.
Summers are generally dry with some drought.
High-pressure belts dominate these regions.
They are under the influence of trade winds blowing over dry land masses.
Mild with temperatures averaging 4*C and 6*C.
Sun is still high for warm conditions.
Prevailing wind is south-westerly. It is a warm wind as it blows from lower latitudes.
Winters are moist with rainfall between 400-700mm.
Prevailing winds blow over the Atlantic ocean, bringing moist air.
Depressions from over the Mediterranean Sea.
Rain falls in heavy showers.
Vegetation in Mediterranean regions.
-The natural vegetation is evergreen woodland. Eg Cypress, cedar, olive.
-They adapted because:
They absorb and store moisture during winter.
They have very thick bark and waxy leaves to prevent moisture loss.
They are widely spaced to avoid competition for moisture.
-Because woods were cleared, there was new vegetation that took over consisting of low-lying heathers and herbs.
Eg thyme, lavender, rosemary.
The changing Mediterranean landscape.
-Human activity has changed the landscape over thousands of years, most woodland had been cleared for agriculture.
-Sheep and goats are commonly reared.
Overgrazing has damaged vegetation and soil has been exposed to erosion by sudden downpours of rain.
-Tourism is the most important industry in many coastal areas. Eg The Costa del Sol.
Tourism has led to:
badly planned developments.
Characteristics of equatorial climates. (Tarzan)
Hot all year around. (average 32*C)
Rainfall every afternoon.
High level of humidity.
Annual total: over 2000mm.
Hardwoods (mahogany, teak, cherry)
Rain forest (jungle)
Exotic birds eg parrots
snakes, monkies, butterflies.
Characteristics of a cold climate - boreal climate.
Summer- short, long hours of daylight.
Coastal areas are cool (about 10*C)
Inland areas are warmer. (about 15*C)
-The northern hemisphere is tilted towards the sun
-Long hours of sunshine allows land to absorb some heat
Winters- cold, long hours of darkness. Temps of -25*C
-Northern hemisphere is tilted away from sun
-Sun is low in sky, so rays have to cover a large area of ground, fivijg little heat.
Generally less than 400mm per annum. Mainly in form of snow.
Maximum precipitation occurs in summer.
-Polar winds too cold to hold moisture
-Many boreal regions are far from sea, so winds that blow over them are dry.
Natural vegetation in boreal climates + how trees have adapted
-evergreen forest called taiga
-Needles prevent moisture loss
-Trees have a cone shape and branches slope down so snow will slide off.
-Thick bark retains moisture and gives protection from cold winds.
-Roots spread out widely to gather moisture and nutrients.
-Roots are shallow because there is a only a thin layer of soil above permanently frozen ground (permafrost)
-They keep their needles all year around so when the sun comes out again in the spring, these trees are already gathering sunlight rather than wasting energy to grow more needles.
Wildlife in a boreal climate + how they adapted
Wildlife in the boreal include bears, minks, wolves and the eagle.
-The grizzly bear avoids the stress of winter by hibernating. They also have fur which acts as an insulating layer to keep their bodies warm in winter and cool in the summer.
-Birds fly south during the winter.