Abstract: Based on the daily temperature and wind speed data, and relevant parameters provided by the heat supply sector of Hohhot during 1962-2007, and the relevant heating regulation, by means of mathematic statistics methods, the temporal evolution of winter heating and the impact of climate warming on the energy consumed for winter heating are analyzed. It is concluded that with climate warming, the heating period has been shortened by 30 days, especially after 1988 when an abrupt change in daily average temperature took place; the energy consumed in the heating period is closely related with the duration and degree-day of the heating period each year, and they both have shown a significant decline trend in past 46 years, indicating that the winter in Hohhot is warming and the cold period is getting shorter, therefore, the energy consumed is reduced: 88% of the years when the energy consumed in the heating period was more than normal occurred in the period of the 1960s to 1970s, and 85% of the years when the energy consumed was less than normal appeared in the period of the 1990s to now, suggesting that the persistent warming period started from the 1990s.

Key words: climate warming, heating period, energy consumed, energy conservation