Exploration of New Criterion for Extreme Hot Weather Warning in China

In this study, two indices of temperature and HUMIDEX are used to analyze the extreme hot weather conditions in 2011 in seven metropolitan cities in China, which have different climate types. Among the seven cities, four are inland cities and three are located along coastal areas. Comparing to temperature which has been currently used as the criterion to issue hot weather warning in China, HUMIDEX which has considered the influence of both temperature and humidity is more appropriate and reliable to evaluate the heat discomfort. It is recommended that HUMIDEX can be used as an auxiliary criterion based on current temperature criterion to issue hot weather warnings in China. The criterion is applicable to the whole country. This study is valuable to provide reliable information that can help the government, civilian, industrial and public health agencies to identify heat stress conditions that are likely to be harmful to human health so they can implement appropriate health services and precaution.