Across
1
Where river meets the sea
4
Large body of water partly enclosed by land
5
Cold treeless Arctic plain
8
Vast body of salt water
9
Land surrounded by water on three sides
11
Largest ocean on Earth
12
Body of water surrounded by land
Down
2
Flat grassland in tropical regions
3
Chain or group of islands
6
Deep narrow valley with steep sides
7
Long-term weather patterns of an area
10
Large area covered with trees