As you just saw in the California example, temperature also has a large impact on settlement patterns. In general, the lower the latitude, the warmer the temperature, and coastal waters also moderate temperatures. With this information in mind, where would you expect most of the earth's population to live? As you might guess, coastal regions and middle to low latitudes tend to have a higher population than do most other areas. There are factors other than weather that determine settlement patterns and we will discuss some of them in other lessons, but temperature and precipitation are two of the leading factors in determining where humans usually choose to settle.

In the Southern Hemisphere there is very little landmass in latitudes that are higher than 40° south, with the exception of Antarctica, which is too cold to support human life for extended periods of time. In the Northern Hemisphere the landmasses reach quite high latitudes, in some areas as high as 80° north. However, as shown in Figure 4.6.3, almost all of the earth's population lives in the mid- or equatorial latitudes. The areas located in higher latitudes, where the temperatures are colder, are sparsely populated. Since Canada, Greenland, and northern Russia are all located in high latitudes, it is not surprising that the population density of those areas is low.