CAREER: Research and education on landscape, climate, and biophysical controls of the urban water cycle amid urban warming and global change

地球上的大多数人口现在生活在城市地区。在城市中，人类密集地重新配置了景观，广泛地集中了资源。这些城市周围地区预计将容纳未来几乎所有的全球人口增长。然而，城市在未来是否以及如何保持宜居，是一个关键问题。宜居的关键因素包括舒适的环境、获得和有效利用水，以及对极端干旱、洪水、寒冷和炎热的适应能力。自然科学表明，这些因素与一个地方的植被覆盖、土壤以及热和水平衡密切相关，但在农村和自然地区进行的自然科学课程如何准确地应用于城市是一个悬而未决的问题。城市最突出、最独特的特征之一是其土地覆盖的极端空间差异(例如，草地、人行道、树木、花园和短距离并列的裸露地面)和被称为城市热岛(UHI)的现象。在城市地区比附近的农村地区温暖得多的地方会发生城市热岛，这是由于铺设路面对太阳能的吸收更多，以及城市干燥表面的蒸发冷却比农村田野或森林更少等因素造成的。该项目将决定(1)城市景观变化、热量和水平衡如何作为城市内局部冷热小气候的因果关系；(2)小气候及其植被和水文影响如何与城市人类健康和舒适度相关；(3)如何使城市的整体城市热岛气候和水文状况更能适应极端天气，从而有利于城市基础设施、城市环境质量和城市人类安全。如果一个城市的地表水和能量平衡可能受其景观构成和配置的控制，对城市异质性--热-水关系有足够的了解，就可以设计出更健康和更可持续的城市，即使面对全球变化也是如此。该项目的双重目标是(1)量化城市景观异质性、城市热量和城市水循环之间的联系和反馈；(2)在科学、教育和管理之间建立一条强大的管道，帮助所有能力和职位的人制定实践，以提高城市景观面对全球变化的舒适性和弹性。这项研究将探讨城市环境中分布的地表水和能量平衡是如何发挥作用的，它们在城市热岛或凉岛中的作用是不同的，它们如何受到不同类型的土地覆盖的控制，以及它们如何反过来影响水资源需求和人类舒适度。研究方法将包括：对受同一小气候岛影响并在不同小气候之间进行比较的最常见城市土地覆盖的热与水平衡进行现场定量监测；对城市土壤水分对城市变暖的控制进行实地、遥感和模拟调查；利用物理学方法对城市景观组成和结构进行数值模拟；对小气候、地表能量平衡和地表水平衡产生影响；对正在进行的城市化和变暖以及所考虑数据的规模如何影响城市热能和水循环的量化进行遥感和模拟评估。该项目还将通过多种开放获取创新促进研究-教育-管理的协同效应。将为不同年龄段(从学龄前到毕业)开发城市环境科学实地课程模块，以促进基于地点的、体验式的和终身的STEM学习。这些模块还将明确设计，使有行动需求的学生能够接触到实地科学。研究-管理合作将在美国西部城市和大学的一个联合体中进行，“城市后院科学”的公众宣传将免费为所有年龄的人分发教育城市环境活动。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A majority of Earth's population now lives in urban areas. In cities, humans have intensively reconfigured the landscape and extensively concentrated resources. These urban environs are expected to host almost all future global population growth. If and how cities will remain livable in the future, however, is a critical question. Key factors of livability include a comfortable environment, access to and efficient use of water, and resilience to extremes of drought, flood, cold, and heat. Natural science suggests that these factors are strongly related to the vegetation cover, soils, and heat and water balances of a place, but it is an open question how precisely lessons from natural science conducted in rural, natural areas might apply to cities. Among the most prominent, unique characteristics of cities are their extreme spatial variations in land cover (e.g., grass, pavement, trees, gardens, and bare ground juxtaposed over short distances) and the phenomenon called the urban heat island (UHI). An UHI occurs where an urban area is substantially warmer than nearby rural areas due to factors such as greater absorption of solar energy by paved surfaces and less evaporative cooling from dry urban surfaces than rural fields or forests. This project will determine (1) how urban landscape variations, heat, and water balances interact as cause and consequence of local hot or cool microclimates within the city, (2) how microclimates and their vegetative and hydrologic influences relate to urban human health and comfort, and (3) how the overall UHI climate and hydrologic regime of cities may be made more resilient to weather extremes for the benefit of urban infrastructure, urban environmental quality, and urban human safety. To the extent that the linked surface water and energy balances of a city might be controlled by is landscape composition and configuration, with sufficient knowledge of urban heterogeneity-heat-water relations, cities could be engineered for greater health and sustainability, even in the face of global change. The dual goals of this project are to (1) quantify the links and feedbacks between urban landscape heterogeneity, urban heat, and the urban water cycle and (2) to forge a strong pipeline between science, education, and management to help empower people of all abilities and positions to develop practices to enhance the comfort and resilience of urban landscapes in the face of global change. The research will address how the distributed surface water and energy balances of the urban environment function, whether they function differently in urban heat or cool islands, how they are governed by various types of land cover, and how they in turn affect water resource demands and human comfort. Research approaches will include in situ quantitative monitoring of the heat and water balances of the most common urban land covers subject to the same microclimate island and compared among different microclimates; field, remote sensing, and modeling investigation of urban soil moisture's controls on urban warming; physics-based numerical modeling of urban landscape composition and configuration controls on microclimate, surface energy balance, and surface water balance; and remote sensing and modelling assessments of how progressive urbanization and warming and the scale of data considered may influence the quantifications of urban heat and water cycles. This project will also foster research-education-management synergy with multiple open-access innovations. Urban environmental science field course modules will be developed for a variety of age levels (pre-school to graduate) to foster place-based, experiential, and life-long STEM learning. The modules will also be explicitly designed to make field science accessible to students with mobility needs. Research-management collaboration will occur among a consortium of western US cities and universities and public outreach on "urban backyard science" will freely distribute educational urban-environment activities for all ages.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.