Why does the kalahari dessert have seasons that are different from the northern hemisphere

Odds are, human beings hit upon the lifestyle and innovations that enabled them to populate the planet in some place very like the Kalahari Desert, a small, surprisingly diverse, just-barely desert in southern Africa that still harbors what many geneticists consider the original human beings. The 100,000-square-mile (260,000 sq km) Kalahari is a faint echo of the vast Sahara Desert. The Kalahari is a desert for two reasons. First, it is just as far south of the equator as the Sahara is north, which means that it is a Southern Hemisphere desert for the same reason that the Sahara is a Northern Hemisphere desert and subject to the same drying, descending winds. Second, the Kalahari sits on a plateau about 3,000 feet above sea level and is bounded by mountains to the north and south, which cast a long rain shadow.

The Kalahari occupies central and southwestern Botswana, part of west central South Africa and part of eastern Namibia. It is part of a vast 360,000-square-mile (930,000 sq km) sand basin that stretches into Angola and Zambia in the north and takes in much of South Africa and Namibia. This larger region has great dune fields that have been frozen into place by a covering of plants, which indicates that it is part of a fossil desert. At some point it converted from true desert to arid grasslands as a result of climate shifts. A Southern Hemisphere desert with seasons reversed from the Northern Hemisphere, temperatures range from 95 to 113°F (35–45°C) in the hot months from October to March and often drop below freezing in the winter months of June to August.

Explanation:

1. read the following excerpt from franklin d. roosevelt's "fireside chat 19":

on the other side of the picture, we must learn also to know that guerilla warfare against the germans in, let us say serbia or norway, us; that a successful russian offensive against the germans us; and that british successes on land or sea in any part of the world strengthen our hands.

remember always that germany and italy, regardless of any formal declaration of war, consider themselves at war with the united states at this moment just as much as they consider themselves at war with britain or russia. and germany puts all the other republics of the americas into the same category of enemies. the people of our sister republics of this hemisphere can be honored by that fact.  

the true goal we seek is far above and beyond the ugly field of battle. when we resort to force, as now we must, we are determined that this force shall be directed toward ultimate good as well as against immediate evil. we americans are not destroyers — we are builders.

analyze the effectiveness of this excerpt. how does it function within the speech as a whole? how does the structure of the excerpt to convey the speech's purpose and key points? support your argument with evidence from the speech. (10 points)

i don't see it in your profile.