Finland is located in an area where global warming is estimated to besignificantly stronger than the global average warming. Surveys show that average temperatures will rise 2-7 degrees in Finland by 2080. Very low temperatures will become more unusual and heat waves become more common in summer. Temperature rises especially in winter and at night.
SILMU program scenarios with temperature increases cause the northern coniferous trees move about 400 - 500 km to the north and deciduous trees become more common everywhere in Finland. In neighbouring areas wintering several migratory birds’ spring migration have become earlier. Butterflies have expanded their distribution because in 2001 they found 18 new butterfly species in Finland. In many places the growing season has increased by more than ten days in 30 years.
Climate change also affects to accumulated precipitation. Rainfall will increase especially in winter. Initially heavy snowfalls may become more general, especially inland and in northern Finland. Cloudbursts are expected to increase more than average rain. The models formed by Finnish Environment Institute (SYKE) and FMI tell that very large rainfalls increase 35-65 percent by the end of the century. The increase should be greatest in January-June.
By the impact of global warming sea ice decreases and there can blow more in winter especially in coast. Also low pressure routes possible change could affect storms and wind.
These changes affect the flow of watercourses and dam’s safety. Southern Finland’s winter is endangered. Although between it snows, snow melts away and proper snow cover is not accumulated. Round frost is less than now and during mild and rainy winters soil is often wet and its carrying capacity is poor. Melting and rainfalls could cause flooding in the winter. Big lakes’ water levels rise especially in the spring. Similarly the risk of spring flooding remains.
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Luotu: 9.9.2010 14:03
Muokattu: 16.9.2010 18:30