Across
1
Wearing away of land by water or wind
5
Cold treeless Arctic plain
6
Where river meets the sea
8
Half of the Earth
9
Largest river in South America
12
Total number of people in an area
Down
2
Piece of land jutting into the sea
3
City that is seat of government
4
Low-lying land surrounded by higher ground
7
One of seven major landmasses
10
Low area between mountains
11
Landform where river meets the sea