This technology allows for a forecast of weather conditions for a period of three to six months ahead. Seasonal forecasts are based on existing climate data; in particular, on sea surface temperatures, which are then used in ocean-atmosphere dynamic models, coupled with the synthesis of physically plausible national and international models (Oxford Dictionary of Geography. A Dictionary of Geography. Copyright © Susan Mayhew 1992, 1997, 2004). Seasonal forecasts can be developed using mathematical models of the climate system (Alexandrov, 2006).