Where do you want to go on vacation?
If you live in a frigid climate you may want to go to lower latitudes for your mid-winter vacation. If you live in the desert, you may like to spend part of your summer at higher latitudes. Different climates are found at different latitudes.
Many factors influence the climate of a region. The most important factor is latitude because different latitudes receive different amounts of solar radiation.
The maximum annual temperature of the Earth, showing a roughly gradual temperature gradient from the low to the high latitudes.
- The Equator receives the most solar radiation. Days are equally long year-round and the Sun is just about directly overhead at midday.
- The polar regions receive the least solar radiation. The night lasts six months during the winter. Even in summer, the Sun never rises very high in the sky. Sunlight filters through a thick wedge of atmosphere, making the sunlight much less intense. The high albedo, because of ice and snow, reflects a good portion of the Sun's light.
Temperature with Latitude
It's easy to see the difference in temperature at different latitudes in the Figure above. But temperature is not completely correlated with latitude. There are many exceptions. For example, notice that the western portion of South America has relatively low temperatures due to the Andes Mountains. The Rocky Mountains in the United States also have lower temperatures due to high altitudes. Western Europe is warmer than it should be due to the Gulf Stream.
- The amount of solar radiation received by the planet is greatest at the Equator and lessens toward the poles.
- At the poles the Sun never rises very high in the sky and sunlight filters through a thick wedge of atmosphere.
- Latitude is not the only factor that determines the temperature of a region, as can be seen in the striped map above.
- Why do the poles receive so much less solar radiation than the Equator considering that it's light for six months at the poles?
- Why is latitude considered the most important factor in determining temperature?
- Look at a map of geological features and look at the temperature map to try to determine why some of the exceptions exist. What's the realtively cool blob north of India?
Use this resource to answer the questions that follow.
- Why does less solar radiation reach the poles?
- What are the mean annual temperatures at the equator? What are they at the south pole?
- How does latitude affect precipitation?
- Where are the regions of rising air?
- Where are the regions of sinking air?
- Why are the Sahara and the deserts of the American Southwest at about the same latitude?
- Why are there lots of forests at 60-degrees latitude? Why is this a stormy region?
- How can the north and south poles be called deserts? Why is there snow there?