顾及地表热力属性的城市群局地气候遥感分区及时空格局

Formally proposed in 2012, the (urban) local climate zone (LCZ) has demonstrated great potential in terms of urban planning as well as the standardization of the urban climate observation and modeling. Remote sensing provides an efficient data source for the LCZ mapping over urban agglomerations. However, the current remote-sensing-based LCZ mapping still faces two key issues: (1) the inputs for an accurate mapping remain insufficient; (2) the LCZ mapping remains considered only at very limited spatio-temporal scales. Under the new fashion of China’s urbanization, the remote-sensing-based LCZ mapping for urban agglomerations is undoubtedly a key step for further interpreting urban climate. For this purpose, the urban agglomeration around the Yangtze River Delta (UAYRD) will be chosen as the case study area. By incorporation of the thermal properties of urban surfaces retrieved by thermal remote sensing, this study will investigate the spatial downscaling of thermal inertia as well as the temporal upscaling of satellite-derived land surface temperatures (LSTs). Based on these spatially downscaled thermal inertia and temporally upscaled LSTs, we will propose an accurate, robust, and effective methodology for the LCZ mapping over the UAYRD. During this process, the mechanisms of the LCZ responsive to the thermal properties of urban surfaces will be examined. This program additionally aims to reveal the regimes of the spatial structure and temporal evolution of the mapped LCZs over the UAYRD as a single agglomeration and as individual cities. Our study is able to deepen the understanding of the macro- and micro- characteristics of urban climates. This program is also expected to assist urban planning and the adaption under climate change; it will additionally contribute to the alleviation of the various climatic and environmental issues over urban areas.

城市局地气候分区概念自2012年被正式提出以来，已在城市规划及城市气候观测与模拟的规范化等方面展现出极大的应用潜力。遥感技术在局地气候分区中发挥着不可替代的作用，然而城市局地气候遥感分区目前仍面临（1）输入要素不够充分与（2）时空尺度存在局限等关键瓶颈。在国家推进新型城镇化建设背景下，适时开展顾及地表热力属性的城市群局地气候分区的遥感研究，无疑是进一步深入理解城市群气候的关键步骤。以长三角城市群为研究对象，以热红外遥感表征的地表热力属性作为切入点，研究热惯量空间降尺度与地表温度时间升尺度方法，构建城市群局地气候遥感分区的理论、方法及优化策略，阐明地表热力属性对局地气候分区的影响机制，揭示城市群各城市局地气候分区的总体空间格局与时间演变规律。研究有望加深对城市群气候宏（微）观结构特征的认知，有望服务于长三角地区城市规划及其对气候变化适应的决策，从而为缓解城市的负面气候和环境问题做出贡献。

城市负面气候效应是我国新型城镇化过程中亟需解决的问题。受限于城市局地气候遥感分区输入要素不足及时空尺度的限制，目前研究尚不能有效描述、归纳及解析城市热岛时空格局变化规律与响应机制。申请人在本项目支持下，取得如下系统性成果：（1）构建了高时空间分辨率地表热力属性表征框架，实现了地表热力属性空间细节特征的有效刻画及其时间动态变化的有效模拟；（2）实现了典型城市局地气候分区制图，阐明了城市局地气候遥感分区框架下地表及冠层热岛多时间尺度变化特征及其变化模态；（3）阐明了城区尺度下城市热岛垂直变化的多时间尺度特征，揭示了区域与全球尺度地表热岛日内典型模态与夜间热岛的响应机制，形成了遥感视角下典型城市局地气候的系统理解。在项目支持下，发表SCI论文15篇（其中以Remote Sensing of Environment为代表的SCI一区或行业顶刊论文13篇）、地理学报等中文核心期刊3篇；申报（授权）发明专利5项；培养博士/硕士研究生8人；获行业荣誉或奖励13次；参加国际/国内学术会议9次，研究成果陆续推出。研究成果进一步夯实与丰富了城市局地气候遥感分区的基础理论与应用领域，能为城市群气候变化的监测、评估与生态适应提供更优解决方案。