Across
1
Low area between mountains
3
Dry land with little rainfall
4
Imaginary line around the middle of Earth
7
Distance east or west of prime meridian
8
Region between the two tropic lines
10
Land surrounded by water on three sides
11
Cold treeless Arctic plain
12
Largest ocean on Earth
Down
2
Half of the Earth
5
Region surrounding the North Pole
6
Largest hot desert in the world
9
Steep rock face at edge of land
13
Mountain that can erupt with lava