Tree Planting for Urban Heat Improvement

From Esri Environment: "Extreme heat events, or heat waves, are on the rise and becoming more intense according to the U.S. Environmental Protection Agency (EPA). These events are more than just an annoyance and can lead to illness and death, particularly among vulnerable populations including seniors and young people. The EPA also states prolonged exposure to these heat events can lead to other impacts such as damaging crops or killing livestock. Climate resilience planning is one approach to preparing for and mitigating the effects of extreme heat. Climate resilience planning in local communities involves several steps including assessing vulnerability and risk. It is a fact that trees can lower the surrounding air temperature through evapotranspiration, providing shade, and taking up space that might otherwise be converted to pavement. Lots of pavement, blacktop roads, and concrete buildings absorb the sun's heat and radiate that heat into the surrounding air. This is especially evident in highly developed urban areas which can get up to 20 degrees warmer than surrounding vegetated areas. These hot zones are referred to as Urban Heat Islands. One way to reduce the warmer temperatures in urban areas is to plant trees and other vegetation. This layer displays census tracts that are ranked according to which would benefit most from tree planting. The ranking is based upon a composite index built with the following attributes: High Summer Average Surface Temperature (°F) Percent of Tract Covered by Tree Canopy (%) Population Density (ppl/km2) These attribute links take you to the original data sources. Preprocessing was needed to prepare many of these inputs for inclusion in our index. The links are provided for reference only." Dates of Data The layer “High Summer Average Surface Temperature” uses data from 2023. The layer “Percent Tract Covered by Tree Canopy” uses data from 2020. The layer “Population Density” uses data from 2019-2023.本数据集源自Esri平台：美国环境保护署（U.S. Environmental Protection Agency, EPA）指出，极端高温事件（又称热浪）的发生频次正持续攀升，且强度不断加剧。此类事件绝非仅带来不便，更可能引发疾病乃至死亡，对老年人、儿童等脆弱群体的威胁尤为突出。EPA同时强调，长期暴露于极端高温环境还会造成其他负面影响，例如损毁农作物、导致牲畜死亡。 气候韧性规划是应对并缓解极端高温影响的有效路径之一。地方社区开展气候韧性规划包含多项核心步骤，其中便包括脆弱性评估与风险研判。 科学研究表明，树木可通过蒸散作用降低周边空气温度，同时提供树荫，并占据原本可被铺设为硬质路面的空间。大量路面、沥青道路与混凝土建筑会吸收太阳辐射热量，并将热量重新辐射至周边空气中，这一现象在高度开发的城市区域尤为显著——此类区域的气温可比周边植被覆盖区域高出最高20华氏度。这类高温区域被称为城市热岛（Urban Heat Islands）。 缓解城市区域高温问题的可行手段之一，便是种植树木与其他植被。本图层展示了按植树收益优先级排序的普查区域（census tracts），排序依据为综合指数，该指数由以下属性构建： 1. 夏季平均地表高温（华氏度，°F） 2. 普查区域树木冠层覆盖率（%） 3. 人口密度（人/平方公里，ppl/km²） 以下链接可跳转至各属性对应的原始数据源。为将各类输入数据纳入本综合指数，我们已完成多项预处理工作。此处提供的链接仅作参考用途。 ### 数据日期说明 - 「夏季平均地表高温」图层采用2023年采集的数据 - 「普查区域树木冠层覆盖率」图层采用2020年采集的数据 - 「人口密度」图层采用2019-2023年采集的数据