Climate is the weather in a specific geographic region. It is measured by long-term statistical distribution of weather conditions and we are particularly interested in changes over a long period of time. Climate is described using measurements such as the annual mean temperature and rainfall as well as climate zones. Climate change is typically presented as variation between the present day and the pre-industrial era (before the 1850s). According to the Climate Guide, Finland's climate is characterised by major variation from year to year. Extensive water bodies and topographic features are among the factors influencing the climate in different regions. Finland's annual mean temperature has risen over 2 degrees C since the middle of the 19th century. On the basis of climate models, the mean temperature is estimated to continue rising and precipitation will increase particularly in winter, torrential rain will become more intense and the snow cover in southern Finland will become more capricious.