28. The icebreaking date for the Tornio River in Finland has been recorded since 1693. With the increased greenhouse effect, impacts on the cryosphere are likely. One impact will be less ice on rivers and lakes. Freeze-up dates will be delayed, and break-up will begin earlier. The period of river-ice could be shortened by up to a month. Many rivers within the temperate regions could become ice-free or develop only intermittent or partial ice coverage.