Contrasting responses of urban and rural surface energy budgets to heat waves explain synergies between urban heat islands and heat waves
Contrasting responses of urban and rural surface energy budgets to heat waves explain synergies between urban heat islands and heat waves
复制标题
城市和农村地表能源预算对热浪的对比反应解释了城市热岛和热浪之间的协同作用
DOI：
10.1088/1748-9326/10/5/054009
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发表时间：
2015-05-01
影响因子：
6.7
通讯作者：
Gao, Zhiqiu
中科院分区：
文献类型：
--
作者：
Li, Dan;Sun, Ting;Gao, Zhiqiu
预计在21世纪后期，热浪（HWs）在大多数陆地地区变得更加频繁，持续时间更长，这引起了严重的公共卫生问题。由于HWs和城市热岛（UHI）之间的协同作用，城市居民面临更高的健康风险（即，HW条件下的UHI较高）。然而，城市和农村的地表能源预算的HWs的反应仍然是未知的。本研究分析了观测从两个通量塔在北京，中国，并揭示了显着差异的城市和农村（农田）生态系统的HWs的响应。据发现，UHIs显着增加在HWs，特别是在夜间，这意味着HWs和UHIs之间的协同作用。结果表明，城市站点接收更多的入射短波辐射和长波辐射由于HWs相比，农村站点，导致更大的辐射能量输入到城市的表面能量收支。湍流热通量的变化也分歧强烈的城市网站和农村网站：潜热通量增加更显着的农村网站，由于丰富的可用水，而感热通量和可能的热量储存增加更多的城市网站。这些比较表明，城市和农村的地表能源预算HWs的对比反应是负责HWs和UHIs之间的协同作用。因此，需要采取城市减缓和适应战略，如使用绿色屋顶和白色屋顶，以减轻这些协同作用的影响。
Heat waves (HWs) are projected to become more frequent and last longer over most land areas in the late 21st century, which raises serious public health concerns. Urban residents face higher health risks due to synergies between HWs and urban heat islands (UHIs) (i.e., UHIs are higher under HW conditions). However, the responses of urban and rural surface energy budgets to HWs are still largely unknown. This study analyzes observations from two flux towers in Beijing, China and reveals significant differences between the responses of urban and rural (cropland) ecosystems to HWs. It is found that UHIs increase significantly during HWs, especially during the nighttime, implying synergies between HWs and UHIs. Results indicate that the urban site receives more incoming shortwave radiation and longwave radiation due to HWs as compared to the rural site, resulting in a larger radiative energy input into the urban surface energy budget. Changes in turbulent heat fluxes also diverge strongly for the urban site and the rural site: latent heat fluxes increase more significantly at the rural site due to abundant available water, while sensible heat fluxes and possibly heat storage increase more at the urban site. These comparisons suggest that the contrasting responses of urban and rural surface energy budgets to HWs are responsible for the synergies between HWs and UHIs. As a result, urban mitigation and adaption strategies such as the use of green roofs and white roofs are needed in order to mitigate the impact of these synergies.