Heat waves in Berlin, Germany - Urban climate modifications

“城市气候变化”项目是作为题为“德国柏林的热浪”的三个项目之一提出的。该项目将与提出“城市树木的水分胁迫”项目的研究伙伴Eva Müler和Gerd Wessolek(柏林工业大学)以及Sebastian Schubert(柏林洪堡大学)合作，研究柏林热浪的发生和特征及其对人类健康的负面影响，Sebastian Schubert(柏林洪堡大学)打算开发一种改进的全球气候预测动态缩减方法，以便在其“气候预测”项目中以柏林为例进行测试。DFG研究单元1736“从气候变化的角度看中纬度城市的城市气候和热应力(UCaHS)”，资助到2016年年中，例如可以揭示，在21世纪的头十年里，每年都会发生几次高于平均水平的温暖天气状况，从统计上讲，这与柏林人口死亡率的上升高度相关。在这个项目中，我们将研究如何进一步改进UCaHS开发的基于风险的方法，并将其用于识别热浪。然后，应针对热浪之间气象条件的差异、这些差异与先前气象条件的关系以及城市结构和树木如何造成城市内部差异，来研究通过这种方法确定的热浪。联合研究的目标是研究水分胁迫对气候调节生态系统服务的影响，方法是采用多尺度方法进行蒸腾冷却和遮荫。此外，还应分析城乡差异。来自城市气候观测网络和德国气象局的综合数据集，来自进一步的观测(包括对于上述研究专题，应补充、更新和分析中欧精细分析(CER)的网格数据(涡度-协方差测量)。这包括为个别城市地区和周围地区开发和测试气象和人类生物气象数据的空间汇总方法，以便能够针对热浪造成的危害的空间差异分析综合的、空间分布的风险数据。在这方面，联合研究将以高空间分辨率量化气候预测中的不确定性，并研究它们如何影响未来气候条件下热波的识别和分析。

The project "Urban climate modifications" is one of three projects that is proposed as project entitled "Heat waves in Berlin, Germany". The project shall study occurrence and characteristics of heat waves in Berlin and their negative impacts on human health, in collaboration with the research partners Eva Müller and Gerd Wessolek (Technische Universität Berlin) who propose the project "Water stress for urban trees", and with Sebastian Schubert (Humboldt-Universität Berlin) who intends to develop an improved method for dynamical downscaling of global climate projections for cities to be tested for the example of Berlin in his project "Climate projections". The DFG research unit 1736 "Urban Climate and Heat Stress in mid-latitude cities in view of climate change (UCaHS)", funded till mid of 2016, could e.g. reveal that in the first decade of the 21st century several episodes of above-average warm weather conditions occurred in each year that are statistically highly correlated with increased mortality of Berlin's population. In this project, we shall investigate, how the risk-based approach developed in UCaHS could be further improved and used for identification of heat waves. The heat waves identified by this approach shall then be studied with respect to differences in meteorological conditions between heat waves, how these relate to antecedent meteorological conditions, and how urban structures and trees cause intra-urban differences. Joint research shall target on studying the influence of water stress on climate-regulatory ecosystem services by transpirative cooling and shading using a multi-scale approach. In addition, differences between urban and rural areas shall be analysed. The comprehensive data sets from the Urban Climate Observation Network and from the German Weather Service, from further observations (incl. eddy-covariance measurements), as well as the gridded data of the Central Europe Refined analysis (CER) shall be complemented, updated and analysed with respect to the above-mentioned research topics. This includes development and testing of methods for spatial aggregation of meteorological and human-biometeorological data for individual city districts and areas in the surroundings, such that comprehensive, spatially distributed risk data could be analysed with respect to spatial differences in hazards caused by heat waves. In this context, joint research shall quantify uncertainties in climate projections with high spatial resolution, and study how they influence identification and analysis of heat waves under future climate conditions.