近50年海南岛高温日数和热浪的气候特征

利用1966—2015年海南岛18个气象站日最高气温资料,分析了海南岛高温日数、热浪频次和热浪强度的时空分布特征。结果表明:(1)海南岛年高温日数、不同等级热浪频次和热浪强度呈西北多东南少的空间分布,高值区集中在西北部,低值区分布在沿海地区。其中,昌江年高温日数最多、热浪频次并列最多、强度最强;东方和三亚几乎未出现过热浪。(2)近50年海南岛以持续3~4天轻度热浪为主,且全岛平均年高温日数、热浪总频次总体呈显著增长趋势。其中,轻度和中度热浪频次呈缓慢增长趋势,重度热浪频次变化不明显。除重度热浪外,2003年后年高温日数和其他等级热浪频次大多处于偏多年份。年热浪强度增长趋势不显著,但2000年后明显增强。(3)区域变化特征分布不均匀。大部分地区的年高温日数、年热浪和轻度热浪频次增长趋势显著,但年热浪强度、中度和重度热浪频次变化趋势的空间分布不均匀,且绝大多数地区趋势不显著。

Climatic Characteristics of High Temperature Days and Heatwaves: Hainan Island in Recent 50 Years

Based on daily maximum temperature data of 18 meteorological stations in Hainan island during 1966-2015, the temporal and spatial distribution characteristics of high temperature days, frequency and intensity of heatwaves in Hainan island were analyzed. The results showed that: (1) for spatial distribution of annual high temperature days, frequency of different-class heatwaves and heatwaves intensity, there were higher in the northwest than in the southeast, that was, the high-value regions concentrated in the northwest, while the lower regions distributed in coastal areas, thereinto, annual high temperature days in Changjiang was the most, heatwaves frequency ties was the most, heatwaves intensity was the strongest; there was almost no heatwaves in Dongfang and Sanya; (2) in the last 50 years, light heatwaves with 3-4 days duration was the main type in Hainan island, and average high temperature days, total heatwaves frequency showed an overall increasing trend, thereinto, frequency of light and moderate heatwaves showed a slow increasing trend, variation of severe heatwaves frequency was not obvious; except severe heatwaves, high temperature days and frequency of other class heatwaves were more in most years after 2003; the increase trend of heatwaves intensity was non-significant, but it had increased obviously after 2000; (3) regional variation characteristics presented the non-uniform distribution, the annual high temperature days, frequency of annual heatwaves and light heatwaves in most areas had significant increasing trend, however, trends of annual heatwaves intensity, moderate and severe heatwaves frequency presented the non-uniform distribution and were non-significant in most areas.