continent
one of the large landmasses of the earth
climate
the weather in some location averaged over a period of time
barrier
a structure or object that impedes free movement
tropical
relating to part of the Earth's surface with hot climate
savanna
a flat grassland in tropical or subtropical regions
tundra
a vast treeless plain where subsoil is permanently frozen
vegetation
the process of growth in plants
evaporation
the process of becoming a suspension of particles in the air
precipitation
the falling to earth of any form of water
erosion
the process of wearing or grinding something down
condensation
process of changing from a gas to a liquid or solid state
flood
the rising of a body of water and its overflowing onto land
corrosion
erosion by chemical action
magnitude
the property of relative size or extent
atmosphere
the envelope of gases surrounding any celestial body
arid
lacking sufficient water or rainfall