Across
1
Total number of people in an area
4
Region between the two tropic lines
8
Deep narrow valley with steep sides
9
Large area covered with trees
10
Large natural elevation of earth
Down
2
Distance east or west of prime meridian
3
Wearing away of land by water or wind
5
Large body of water partly enclosed by land
6
Largest hot desert in the world
7
Cold treeless Arctic plain