Climate change and freezing conditions in Finland

Ground freezing and thawing are connected to the annual cycle of temperatures. The freezing-thawing cycles seriously affect to the way of living and building in cold regions. To limit frost damage, frost protection measures are required and applied to buildings and infrastructure. In Finnish design codes of practice, different occurrence periods of climatic stress i.e. freezing index is set for different structures. In the statistical analysis of temperature observations over a period of 30 years at 30 observation sites in
Finland a clear and apparently linear relationships were found between the local mean annual air temperature (MAAT), local freezing index and local thawing index. From these relationships it could be predicted that the rise of MAAT by 2oC (until 2050) might decrease the local freezing index for approximately 10 000 Kh, and consequently increase the thawing index for approximately 8000
Kh. The mean frost penetration would decrease from 1.2 to 0.7 meters in southern Finland, and from 2.0 to 1.7 meters in northern Finland. Other impacts include reduction or disappearance of permafrost in northern Lapland, earlier beginning and ending of thawing season and more serious intensity of thaw weakening.