Across
1
Land surrounded by water
4
Deep narrow valley with steep sides
6
Low area between mountains
7
Area where water covers the soil
8
Wearing away of land by water or wind
11
Raised area of land, smaller than a mountain
12
Largest ocean on Earth
Down
2
Long-term weather patterns of an area
3
Imaginary line around the middle of Earth
5
Distance east or west of prime meridian
9
Flat grassland in tropical regions
10
Seasonal heavy rainfall