What kind of waves move through earth by causing particles of rocks to move at right angles to the direction of the waves?

When a dam is built in a hot, dry area, creating a lake or reservoir aboved the dam, how does the evaporation from that reservoir affect the environment ?

At a continent-continent convergence,

Can someone me choose a broad topic and area of focus i am really doing this as a tally to see which one most people pick ok water pollution global warming endangered species atmosphere for the !