Wintering South of the Border
Many Species Share a Small Area

Did you notice that the Northern Hemisphere has more land mass than the Southern Hemisphere does?

The blue shows the land mass in the Northern Hemisphere. (Click to enlarge.) The blue shows the land mass in the Southern Hemisphere. (Click to enlarge.)
Maps: National Center for Atmospheric Research

Try This!

  1. Enlarge the first map. Use the grid (latitude and longitude) lines to estimate the square units of land (in blue) in the Northern Hemisphere.

  2. Enlarge the second map. Use the grid (latitude and longitude lines) to estimate the square units of land there.
    Note: 97% of Antarctica (covering the south pole) is always covered in thick ice and snow. You can leave that out when counting square units.

  3. How do the land masses in the hemispheres compare? What is the ratio of land to water in each hemisphere?

    Ratios: Land and Water
    Northern Hemisphere: for every 1 unit (e.g., square mile) of land, there are . . . 1.5 units of ocean.
    Southern Hemisphere: for every 1 unit of land, there are . . . 4 units of ocean.

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