Difference between revisions of "Earth Science 7-1 Africa"

Revision as of 21:01, 21 November 2011

Africa

By Cam Cook, Peter Stone and Sarah VanLoh

African Countries:

South Africa, Botswana, Namibia, Zimbabwe, Zambia, Angola, Mozambique, Tanzania, Democratic Republic of the Congo, Congo, Gabon, Cameroon, Central African Republic, Chad, Sudan, Egypt, Libya, Niger, Nigeria, Algeria, Tunisia, Mali, Morocco, Western Sahara, Mauritania, Senegal, Gambia, Guinea Bissau, Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo, Benin, Madagascar, Eritrea, Djibouti, Malawi, Lesotho, Swaziland, Rwanda Burundi, Kenya, Uganda, Somalia, Ethiopia, Burkina Faso, Canary Islands, Cape Verde, Equatorial Guinea, Sao Tome and Principe, Comoro [1]

African Latitude and Longitude:

51 degrees West to 18 degrees East, 33 degrees South to 37 degrees North [1]

Bordering Oceans:

Atlantic Ocean, Indian Ocean, Mediterranean Sea, Red Sea, Arabian Sea [1]

Large Bodies of Water, Rivers:

Lake Victoria, Zambezi River, Orange River, Lake Nyasa, Lake Tanganyika, Congo River, White Nile River, Blue Nile River, Nile River, Niger River, Benue River, Volta River [1]

Elevation Range, highest/lowest points:

Lac' Assal (lowest) -155 meters, Kilimanjaro (highest) 5895 meters [1]

Major Topographic Features:

Sahara Desert, Lac' Assal, Great Rift Valley,Kalahari Desert, Namib Desert, Congo Basin, Kilimanjaro, Victoria Falls [1]

Climate Zones:

Humid Subtropical (CWa), Subtropical Desert (BWh), Tropical Monsoonal (Am), Tropical Savanna (Aw), Subtropical Steppe (BSh), Mid-lattitude Desert (BWk), Mid-lattitude Steppe (BSk), Marine West Coast (Cfb), Humid Subtropical (Cfa)  [2] 
     

Average Monthly Precipitation:

0 inches( Sahara Desert and part of Southern Africa), 1 inch ( Southern Africa and a little bit of near the edges of the Sahara Desert), 2 inches ( Part of Southern Africa, Western Africa, and a little bit in Northern Africa), 3 inches (part of Southern Africa and part of Central Africa), 4 inches ( a little bit of Central Africa), 5 inches ( Central Africa), 6 inches (Central Africa), 7 inches (Central Africa), 8 inches (Central Africa), 9 inches ( a tiny bit of Central Africa) [3] 

Average Monthly Rainfall:

250 millimeters per month [4]

Effect of Latitude on Climate:

Most of Africa gets little rain and is very hot due to the fact that it is in the mid latitudes and some of it is on the equator. The Sahara Desert, the hottest and driest part of Africa, is located around 30 degrees North latitude near the Horse Latitudes, where the hot air sinks which makes little to no wind or rain. [5]

Effect of Elevation on Climate:

The Sahara Desert is very flat which causes it to remain warm all of the year.  In the higher elevation, like Mt. Kilimanjaro, there can be snow most of the year, and weather stays relatively cool.  Most of Africa is in between these elevations, so weather changes per season in these areas and has relatively moderate weather and climate. Air pressure is also very low in high areas and very high in flat areas. [5]  

Effect of Topography on Climate:

Africa has a very diverse topography.  In areas that are desert-like, the climate is very hot because the ground radiates the heat that it absorbs.  In areas near lakes or rivers or the ocean, the coolness of the water keeps the land around it nice and cool as it goes under the hot air rising from the land.  There is very little wind in the deserts but there is wind near water as the cool air over the water goes towards land.  In mountainous areas, there can be winds due to valley and mountain breezes.  It also stays cool on mountains due to its altitude. [5]

Effect of the Proximity to Water on Climate:

In areas right on water, the water cools the land by sea breezes and the air is very humid. In areas near the center of Africa, where there isn't much water, the climate remains mostly hot and dry such as in the Sahara Desert.  This is part of the reason why there is so much desert in the center of the continent and not near the ocean. [5]

Effect of Prevailing Winds on Climate:

North of the Equator, the prevailing winds go from 30 degrees North to the Equator from the high to the low and curve to the right due to the Coriolis Effect.  The same thing occurs South of the Equator except the winds curve to the left.  These cause the hot air to heat the areas that it goes over and likewise with the cool air.  The Trade Winds also occur in Africa between 30 degrees and the Equator in both hemispheres.  These heat the land that they travel over and make the land windy. [6]

Effect of Vegetation on Climate:

 In areas where the vegetation is thickest, the land is cooler because the vegetation absorbs much of the heat that hits the ground.  In areas with little vegetation, it stays hotter because land without vegetation radiates the heat.  Vegetation helps to absorb sunlight to make photosynthesis. [5]

Effect of High or Low Pressure Zones on Climate:

In low pressure zones, the air heats and rises which causes the land around it to be quite hot.  In high pressure zones, the air sinks and cools which causes land to cool as well.   The Equator is a low pressure area so everything around it is hot.  Everything near 30 degrees latitude in both hemispheres are high pressure areas which causes the cool air to sink and cool the land around it. [5]

Effect of Ocean Currents on Climate:

On the Western side of Africa, in the Atlantic Ocean, the water currents are moving towards the Equator.  This means that the current is carrying cold water to the Equator  where it will be heated.  This cold water current cools the land beside it.  On the Eastern side of Africa, in the Indian Ocean, the currents are moving away from the Equator which means that the water is warm.  This causes the land next to it to warm up. [7]

Current African Natural Disasters:

Nyamulagira Volcano erupted in the Democratic Republic of the Congo in Virunga National Park but is not moving fast enough to cause harm to wildlife or humans.  This volcano is the most active in Africa  and erupts every 2 years and erupts from days to months straight. 
It also reached 116 degrees Fahrenheit in Skukuza, South Africa, due to its nearness to 30 degrees and the Horse Latitudes and that it is inland. [8]

References

    [1] https://www.cia.gov/library/publications/the-world-factbook/graphics/ref_maps/pdf/africa.pdf
    [2] http://www.shr.noaa.gov/jetstream/global/climate_max.htm
    [3] http://www.meteo.psu.edu/%7Enese/4_8_africa_precip.bmp
    [4] http://www.fao.org/docrep/X5318E/x5318e02.htm
    [5] Earth Science Textbook
    [6] http://kids.earth.nasa.gov/archive/nino/global.html
    [7] http://www.windows2universe.org/earth/Water/ocean_currents.html 
    [8] https://www.sjs.org/ftpimages/80/download/HoustonChronicle11-13.pdf