Weathering is more rapid in humid, tropical regions than in temperate regions. This is because tropical areas receive more rainfall, which encourages chemical weathering such as carbonation. Also, tropical areas are warmer, and the rate of chemical weathering doubles with every rise of 10°C. Deserts have little soil because moisture is so low and the rate of chemical weathering is slow. Recall that chemical weathering is responsible for the formation of soils Bedrock commonly occurs at the surface.