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The presence of water and changing temperature. Weathering happens less in very hot and dry areas, as well as places that are extremely cold and dry, where the temperature does not change much. |
Weathering is a natural process, but human activities can speed it up.
For example, certain kinds of air pollution increase the rate of weathering. Burning coal, natural gas, and petroleum releases chemicals such as nitrogen oxide and sulfur dioxide into the atmosphere. When these chemicals combine with sunlight and moisture, they change into acids. They then fall back to Earth as acid rain.
Acid rain rapidly weathers limestone, marble, and other kinds of stone. The effects of acid rain can often be seen on gravestones, making names and other inscriptions impossible to read.
Credit: National Geographic Society
Picture Credit : Google
