高温热浪暴露风险评价——以内蒙古包头市为例

高温热浪事件作为气候变暖带来的严重后果之一，其对社会经济和人群健康影响较大，已成为政府及学术界共同关注的焦点。以包头市为例，采用2001-2014 年气象和遥感数据，通过人口高温暴露风险评价模型，分析包头市高温热浪时空分布特征，并进行人口高温暴露风险评价。结果显示：（1）包头市高温热浪出现在2001、2005、2010 年和2011 年，尤其2010 年出现连续8 d 以上的高温热浪，极端最高温达到40.1 ℃，2005 年出现最高温40.4 ℃，2003、2004 年和2009 年温度较低，高温区分布在工业、住宅和商业区，林地、耕地、园地、公园及广场绿地和水域等地温度普遍较低。（2）人口高温暴露极高和高风险区处于东河区，中等风险区主要分布于昆都仑区和青山区住宅和商服用地，低风险区分布在青山、昆都仑和九原区工业和人口分布相对较少区，无风险区分布在城市绿地覆盖和水域等区域，低、中等风险区面积有所增长，高风险区逐渐转成中等风险区，极高风险区影响不大。

Risk assessment of population exposure to heat wave: a case of Baotou City,Inner Mongolia,China

Heat wave event accompanying with global warming has a great influence on the social economy and human health. Baotou City, the largest industrial city in the Inner Mongolia Autonomous Region of northern China, was selected as the study area. Land surface temperature of Baotou City was retrieved by the method of single-window algorithm using 8 periods remote sensing images from the Landsat 5 TM taken in 2001 to 2011 and 2 periods Landsat 8 OLI in 2013 and 2014. Then, the spatial distribution of ground temperature(2 m height from the ground)in Baotou City in recent 14 years was analyzed by building the relationship between land surface temperature and daily maximum air temperature recorded at weather station. Finally, with the population data of Baotou from 2001 to 2014, population exposure risk to high temperature was evaluated in the four districts in Baotou City, which were Kundulun District, Qingshan District, Donghe District and Jiuyuan District. The results show as follows:(1)during the recent 14 years, heat waves in Baotou appeared in 2001, 2005, 2010 and 2011, especially in 2010, the heat waves had appeared for 8 consecutive days with high temperature(40.1 ℃); the highest air temperature reached 40.4 ℃ in 2005, while the temperature was relative low in 2003, 2004 and 2009, the lowest temperature was 33.3 ℃ in 2003. The high temperature zones were distributed in the industrial, residential and commercial zones; whereas the temperature in areas of forest, farmland, garden, green space of park and square, water was relatively low.(2)According to the risk assessment for population exposure to high temperature, the area of low and medium risk zone increased, and the area of low risk zone reached the highest in 2008; the area of high risk zone gradually turned into medium risk zones with the change of urban green area; the area of extremely high risk zone was the least and appeared only in 2002 and 2004. The extremely high and high risk zones were distributed in Donghe District; the medium risk zones were mainly distributed in residential and commercial zones of Kundulun and Qingshan District; the low risk zones were distributed in industrial zones and the relatively less population area of Qingshan, Kundulun and Jiuyuan District, no risk zones were distributed in urban green space and water area. This research not only has innovation in theory and method, but also has great practical significance. However, two points are expected to be improved:(1)the selected remote sensing images were not in the same month(from June to August), and the correlation coefficient between land surface temperature from images and air temperature recorded at weather station was only 0.65, it can influence the spatial distribution of high temperature heat waves to some extent; (2)in the process of the risk assessment for population exposure to high temperature, the result was influenced by some factors, including less detailed demographic data of communities, and the subjective weight of population distribution based on urban land use.