Geography revision cards

it is a type of sub aerial process and occurs when there are days of alternating warmer and colder climates for example freezing in the night and melting during the day. when it rains, rain water collects in gaps in the cliff face, if the temperature drops below freezing, water turns into ice, when it does so it expands by 9% putting pressure on surrounding rock,  over many years of expanding and contracting loose rock begins to break off, this loose material may be seen on a slope at the bottom of the cliff and is known as scree