Customisable Urban Model for Quantifiable Thermal Observations (CUMQUAT)

随着城市化程度的提高，城市热岛预计会增加，从而增加居民在炎热天气期间患与热有关的疾病和死亡的风险。人为的气候变化已经使2003年夏季热浪发生的可能性增加了一个数量级，预计到21世纪40年代，这样的夏季将成为常态。而最近的2022年热浪估计又造成了3271人死亡。尽管如此，除了简单地增加城市绿地，英国政府目前还没有关于如何应对城市热岛的政策。毫无疑问，这是基于长期以来的信念，即在城市地区增加植物或水将通过增加蒸发蒸腾来提供冷却。然而，情况要复杂得多，无论是绿色空间还是蓝色空间，冷却效果都取决于绿色空间或蓝色空间的大小、形状、分布和类型。这还不包括当地的气候条件、一年中的时间、周围的表面粗糙度、可用的取水长度以及周围城市的几何形状和物质。目前，我们对所有这些因素之间的相互关系的理解存在差距，导致绿色和蓝色空间提供很少或根本没有有用的冷却，在蓝色空间的情况下，实际上可能会恶化环境条件在炎热的时期，如热浪。与绿地相比，绿地对城市小气候的影响研究较少。该项目旨在通过建立一个世界领先的测试设施来缩小我们在理解上的差距，以研究蓝色空间对城市微气候的影响。CUMQUAT阵列将允许在自然环境负荷下对城市设置中不同大小和配置的蓝色空间进行控制测试。部署的环境传感器的数量和种类将允许采用“皮带和支架”的方法来收集数据，并为创建用于验证数值模拟的详细数据集提供足够的数据，同时还可以探索在不同环境负载模式下发生的各种传热和传质机制。CUMQUAT阵列的用途超出了本提案中详细介绍的实验，它将使研究人员能够更好地了解城市水体的行为。例如，城市水体什么时候提供冷却效果？这种效果横向传播到什么程度？城市水体什么时候恶化当地环境条件，加剧对人类健康和福祉的风险？在什么条件下，城市水体可以促进热量、空气和污染物远离城市地表的垂直运输？更好地了解这些条件将有助于更好地规划城市地区，以纳入蓝色空间，以减少甚至抵消城市热岛，并缓解热浪和未来的环境变化。

With increasing urbanisation, the urban heat island is expected to grow, increasing the risk to inhabitants of heat related illness and death during hot weather. Anthropogenic climate change has already increased the likelihood of a 2003 summer heatwave by an order of magnitude, and such summers are expected to be normal by the 2040s. While the recent 2022 heatwaves are estimated to have caused an additional 3,271 deaths. Despite this the UK Government currently has no policy on how to combat the urban heat island beyond simply increasing urban green space. This is no doubt based upon the long-held belief that adding plants or water to an urban area will provide cooling by increasing evapotranspiration. However, the picture is far more complex, for both green and blue space, cooling effectiveness depends on the size, shape, distribution and type of green or blue space. This is in addition to the local climate conditions, time of year, the surrounding surface roughness, the available fetch length and the surrounding urban geometry and materiality. Currently there are gaps in our understanding of the inter-relationships between all these factors leading to green and blue spaces that provide little or no useful cooling and in case of blue space may actually worsen environmental conditions during hot still periods such as heatwaves. The effects of bluespace on the urban microclimate is considerably less studied than that of greenspace. This project aims to close these gaps in our understanding through the creation of a world leading test facility into the effects of bluespace on the urban microclimate. The CUMQUAT array will allow the controlled testing of different sizes and configurations of blue space in an urban setting under natural environmental loading. The quantity and variety of environmental sensors deployed will allow a 'belt and braces' approach to data collection and provide sufficient data for the creation of detailed data sets for the validation of numerical simulations, but also exploration of the various heat and mass transfer mechanisms going on under different environmental loading patterns. The usefulness of the CUMQUAT array goes beyond the experiments detailed in this proposal and will allow researchers to gain a better understanding of the behaviour of urban waterbodies. For instance, when do urban waterbodies provide a cooling effect and how far does this spread horizontally, when do urban waterbodies worsen local environmental conditions exacerbating the risk to human health and wellbeing, under what conditions can urban waterbodies promote the vertical transport of heat, air and pollutants away from the urban surface? A better understanding of these conditions will allow urban areas to be better planned to incorporate bluespace to reduce or even neutralise the urban heat island and providing relief from heatwaves and future environmental change.