Abstract: Based on the hourly temperature and relative humidity data of the microclimate automatic meteorological observatory in Shanshuigou Village,Guojiaqiao Township,Wuzhong City from November 2018 to March 2019,and the conventional meteorological observation data of the regional automatic weather station,the characteristics of temperature changes in the greenhouse are analyzed and the forecast method of the minimum temperature in the greenhouse was studied.The results showed that the diurnal variation of temperature in the greenhouse did not change with the change of the weather state,and the temperature reached the diurnal minimum value before the revelation.The daily minimum temperature in the greenhouse mainly occurs from 7：00 to 9：00,while the daily maximum temperature mainly occurs from 11：00 to 14：00.There is a noticeable linear relationship between the daily minimum air temperature,the relative humidity and the daily minimum air temperature outside the greenhouse.Based on this,the linear regression equation of the daily minimum air temperature inside the greenhouse is established.The absolute error of the equation is within 2.0 ℃,accounting for more than 62.5%.The results can provide a technical support for the prevention of meteorological disasters caused by low temperatures and chilling in facility agriculture.

Key words: Solar greenhouse, Daily minimum temperature, Daily average temperature, Forecast