张家口市度假气候适宜度时空分布特征

Spatial-temporal distribution characteristics of holiday climate suitability in Zhangjiakou City

基于1971—2020年张家口市14个气象站点观测数据,利用改良的度假气候指数(MHCI)和数理统计方法分析张家口市坝上和坝下各县(区)度假气候适宜度时空分布特征,进而评价该市度假气候环境,结果表明,(1)张家口市度假气候适宜度主要以舒适和亚舒适等级为主,二者占总体的96.8%,且坝下地区度假气候适宜度优于坝上。(2)全市夏季以舒适等级为主,冬季以亚舒适等级为主,春(秋)季是由亚舒适(舒适)向舒适(亚舒适)过渡阶段。市区、涿鹿和怀来县春、夏、秋季均达舒适等级,张北7月份、赤城7—8月份度假气候环境最优。(3)坝上从5月中旬至9月中旬、坝下从4月下旬至10月中旬为舒适等级,前者度假气候适宜度呈单峰型分布,7月下旬为峰值,后者呈双峰型分布,峰值出现在6月中旬和8月下旬。(4)全市近50 a来MHCI值和“舒适”日数分别以1.5/10 a和1.3 d/10 a的速率显著增长,而“亚舒适”和“不舒适及以下”日数分别以8.9 d/10 a和4.2 d/10 a的速率显著减少。坝上MHCI增长速率最高为夏季(1.8/10 a),坝下最高为春季(2.0/10 a)。(5)影响坝上地区度假气候指数的主要气象因子是气温和风速,其次是云量和降水;影响坝下地区的主要气象因素为气温和云量,其次是湿度、风速和降水,湿度对坝上地区MHCI整个指标体系没有明显影响。

Based on the measured data of daily temperature,relative humidity,precipitation,wind speed,cloud coverage at 14 meteorological stations in Zhangjiakou from 1971 to 2020,Modified holiday climate index(MHCI)and the mathematical statistical methods were used to analyzed the spatial and temporal variation characteristics of holiday climate suitability counties(districts)of Zhangjiakou for evaluating the holiday climate environment.The results showed that,(1)Main holiday climate suitability were comfortable and sub comfortable,accounting for 96.8%of the total,and the holiday climate suitability of Bashang area was better than that of Baxia area.(2)It was mainly comfortable in summer and sub comfortable in winter in Zhangjiakou.Spring(autumn)is a transitional period from sub comfort level(comfort level)to comfort level(sub comfort level).The urban area,Zhuolu and Huailai County all reach the comfort level in spring,summer and autumn.The holiday climate environment of Zhangbei in July and Chicheng from July to August were the best.(3)From mid-May to mid-September in Bashang and from mid-April to early October in Baxia,MHCI reaches the“comfort”level.The former showed a single peak distribution with a peak in late July,while the latter showed a double peak distribution with a peak in mid-June and late August.(4)In recent 50 years,MHCI and“comfortable”days increased significantly at the rate of1.5/10 a and 1.3 d/10 a respectively,while“sub comfortable”and“uncomfortable and below”days decreased significantly at the rate of 8.9 d/10 a and 4.2 d/10 a respectively.The highest growth rate of MHCI of Bashang was in summer(1.8/10 a),and that of Baxia was in spring(2.0/10 a).(5)Temperature and wind speed were the main meteorological factors affecting MHCI in Bashang area,followed by cloud cover and precipitation.Temperature and cloud cover were the main factors affecting MHCI in Baxia area,followed by humidity,wind speed and precipitation.Humidity has no obvious effect on the whole index system of MHCI in Bashang area.