1) “In a climatological sense, it refers to the widespread downward movement of air associated with divergence at the surface, as in an anticyclone. It is invariably associated with dry weather”.
2) Land Surface sinking as a result of withdrawal of groundwater, geothermal fluids, oils, gas, etc. It can also refer to the extraction of solid materials such as coal and salt.
1. Whittow, J., 2000, The Penguin Dictionary of Physical Geography, 2nd ed. London: the Penguin Group;
2. Thomas, D.S.G., Goudie, A., 2000, The Dictionary of Physical Geography, 3rd ed. Malden, Mass, Oxford: Blackwell, 2000. Print.