Doctoral Dissertation Research: Climate-Health Vulnerability: Identifying Climate Thresholds for Heat-Related Illness

在美国，高温是与天气有关的死亡的主要原因。气候变化的一般循环模型预测热浪的严重性、持续时间和强度都会增加，从而使未来的人口面临与高温相关的疾病和死亡的更大风险。该项目的重点是确定与高温有关的疾病的局部到区域范围的模式以及控制这些模式的温度阈值。温度阈值代表气候值(例如，温度、热度指数和湿度)，超过这些值，与高温相关的疾病急诊科入院人数将显著增加。确定温度阈值允许启动早期热预警系统或紧急响应计划。与高温有关的疾病可以通过补充水分或转移到较凉爽的环境中轻松预防；因此，干预是减少与高温有关的疾病的关键组成部分。这项研究还将确定高危人群，他们经历了与高温相关的疾病急诊科入院人数不成比例的情况。之前的研究已经调查了城市中与高温相关的死亡率和发病率。然而，它相对忽视了美国农村地区高温对健康的不利影响。这项研究确定了城市和农村地区的高危人群和危险因素(包括那些处于高危状态的农业和农场工人)。这项研究的目的是了解与高温相关的疾病的时空模式以及它们如何与温度阈值的空间模式相对应。这项研究采用多学科方法来了解影响与高温相关的疾病模式的气候、环境和人口因素。它借鉴了脆弱性理论的人-生态方法、地理学的空间统计方法和气候学的气候阈值确定方法，以确定气候影响与高温有关的疾病的地点和因素。该方法将现有的细粒度发病率数据、人口普查和天气数据进行明确的时空整合，这将是对气候-公共卫生研究的新贡献，并提供关于影响高温相关疾病高发病率的环境和社会经济因素的新发现。对于不同的时间段、年龄、性别和空间位置，确定了广泛的时空关系。这些关系是通过地理信息系统(GIS)框架、用于识别温度阈值的自动免费软件(PYTHON)程序和几种回归技术来建立的，包括地理加权回归、空间回归和多水平建模。虽然这项研究以北卡罗来纳州为背景，并以与高温有关的疾病为中心，但所采用的方法也将适用于其他与气候有关的疾病(如水传播疾病或呼吸系统疾病)，也可用作评估其他地理位置气候健康脆弱性的模型。除了学术传播外，结果还将分发给北卡罗来纳州公共卫生司、卡罗莱纳州综合科学评估、国家气象局、北卡罗来纳州农工部委员会和北卡罗来纳州农工研究所。

Heat is the leading cause of weather-related death in the United States. General circulation models of climate change project heat waves to increase in severity, duration, and intensity, placing future populations at greater risk for both heat-related illnesses and deaths. This project focuses on identifying the local to regional scale patterns of heat-related illness and the temperature thresholds that control these patterns. Temperature thresholds represent climate values (e.g., temperature, heat index, and humidity) beyond which heat-related illness emergency department admissions increase significantly. Identifying a temperature threshold allows for the activation of an early heat warning system or emergency response plan. Heat-related illness can be easily preventable through hydration or relocation to a cooler environment; therefore, interventions are a key component in reducing heat-related illness. This study will also identify high-risk populations that experience a disproportionate number of heat-related illness emergency department admissions. Previous research has investigated heat-related mortality and morbidity in urban cities. However, it has relatively neglected adverse health effects of heat in rural US locations. This study identifies high-risk populations and risk factors in both urban and rural locations (including those with at-risk agricultural and farm workers).This objective of this study is to understand the spatiotemporal patterns of heat-related illness and how they correspond to the spatial patterns of temperature thresholds. This research employs a multidisciplinary approach to understanding the climatic, environmental, and population factors that affect patterns of heat-related illness. It draws from the human - ecological approach of vulnerability theory, spatial statistics from geography, and climate threshold identification from climatology to determine the locations and factors by which climate impacts heat-related illness. The explicit spatiotemporal integration of available fine-grained morbidity data, census, and weather data in the methodology will be a novel contribution to climate-public health research and provide new findings about the environmental and socioeconomic factors that influence high rates of heat-related illness. A wide array of spatiotemporal relationships is identified for different time periods, ages, genders, and spatial locations. These relationships are established through a geographic information system (GIS) framework, an automated freeware (python) program to identify temperature thresholds, and several regression techniques, including as geographically weighted regression, spatial regression, and multi-level modelling. Though set in North Carolina and centered on heat-related illness, the methodology utilized in this study will also be applicable to other climate-related diseases (e.g. waterborne or respiratory diseases) and can also be used as a model to assess climate-health vulnerability in other geographic locations. In addition to academic dissemination, the results will be distributed to the NC Division of Public Health, Carolina's Integrated Science Assessments, the National Weather Service, NC Farmworker Ministry Committee and the North Carolina Farmworker Institute.