The Annual Changes Law of Temperature and Humidity in the Greenhouse in Taigu

In a typical sunny day,diurnal variation of temperature or relative humidity in solar greenhouse has the same trends in a year in Taigu.The minimum temperature and the maximum relative humidity(RH)appear between 7:00 to 9:00,and the maximum temperature and the minimum relative humidity appear between 14:00 to 16:00.Seasonal changes of temperature and RH in the solar greenhouse were obvious.The temperatures in spring and autumn were mild,daily average were 19.5℃ and 15.7℃,respectively.Temperature in summer was averaged up to 30.5℃,and the maximum temperature during the observed days reached up to 59.2℃.The temperature difference between day and night was 42.1℃.The temperature in winter was quite low,and daily average temperature was around 12℃.Temperatures below 10℃were over 10 h in observed days.With respect to the relative humidity,it was higher in winter and spring,close to 100%.RH above 85%would keep 15~16 h,and averaged daily RH were 82% and 80% in winter and spring respectively.The variation of relative humidity in solar greenhouse was the highest in summer and the difference of RH between the maximum and the minimum was 72%,and daily averaged RH was 64%.During the day RH in the greenhouse was lower than 40%,and it continued to about more than 10 h.The difference of RH between the maximum and the minimum was 42%in autumn,the smallest among the four seasons;the maximum RH was 75%,and the daily average was 57%.