Water is the primary cause of most weathering on Earth's surface. It can cause physical weathering through processes such as abrasion, where water erodes and breaks down rocks and soil as it flows over them. Water can also cause chemical weathering by reacting with minerals in rocks and soil to form new compounds, which can weaken the rocks and make them more susceptible to further weathering. In addition, water can create environments that facilitate biological weathering, such as providing habitats for organisms that secrete acids that break down rocks.