Across
1
Height above sea level
3
Line dividing two countries
5
Seasonal heavy rainfall
6
Region near the equator
7
Ridge of rock or coral near the surface
8
Largest river in South America
9
Region between the two tropic lines
12
One of seven major landmasses
Down
2
Mountain that can erupt with lava
3
Low-lying land surrounded by higher ground
4
Dry land with little rainfall
10
Cold treeless Arctic plain
11
Total number of people in an area
13
Wearing away of land by water or wind