A long ridge of sand and gravel deposited by glacier meltwater.

Low-lying land that is drained of water and turned into productive land.

An forested area in the tropics marked by substantial rainfall.

Rapid advances in scientific understanding in Europe in the seventeenth century based on observation, measurement and experimentation.

Narrow finger-like lakes formed by glacial action. Good examples are found in Finger Lakes region in New York State.

The period between ice ages.

Glacial deposits of rock and sediment.

Intellectual belied system developed in 17th and 18th century Europe that's stressed reason over belief and rationality over religion.

The ideological movement by Russian leaders to promote the active creation of a single Russian empire with one religion and a single language.

A type of economic system that is controlled and planned by the central government.

Rapid growth of algae in lakes often due to the amount of run off high in phosphates and nitrogen from farms and lawns.

A long narrow sea inlet with steep sides.