Extreme Heat and Health
Climate and health vulnerability assessment for Harris County, Texas
Heat and Health
Hot and humid weather is typical within Harris County and the Southeast Texas. When temperatures become extremely high and humidity levels peak, heat stroke, heat exhaustion, heat cramps and dehydration become a concern. Certain groups within our community are more at-risk for heat related illnesses.
In addition to the groups depicted to the right, the following groups are also at-risk.
- People with diabetes
- Socially-isolated individuals
- People without access to air conditioning
- People of certain racial and ethnic groups
- People whose primary language is not English
- People experiencing homelessness
- People who work outdoors
Extreme Heat Vulnerability
Because extreme heat can impact people and communities differently, it is important to look at more than just temperatures to determine which areas of our community are most vulnerable. There are physiological, socio-economic, systemic, and environmental factors that also contribute to health outcomes. A vulnerability assessment combines all of these factors together to create a vulnerability score for each census tract. The vulnerability score allows us to compare different areas to one another.
Climate and Health vulnerability is a combination of three groups; exposure, sensitivity, and adaptive capacity.
In this vulnerability assessment, the Built Environment unit of Harris County Public Health (HCPH) measures the degree to which our communities are susceptible to injury, illness, damage, or harm caused by high temperatures and humidity.
This a tool that can be utilized by HCPH and other organizations to provide a data-driven approach to climate and health solutions. This map depicts the overall vulnerability for extreme heat and health throughout Harris County.
The score assigned to each census tract is a combined score calculated based on sixteen different factors. As you progress through the maps you will discover how to the different factors come together to create this heat and health vulnerability assessment.
Exposure to Extreme Heat
Exposure quantifies how much or how little individuals, communities, and populations experience a certain hazard. For this assessment, we are focusing on temperature and humidity.
Temperature and humidity are combined to create a heat index which is used to determine heat advisories and heat warnings in Harris County. Reducing or eliminating exposure to extreme heat is an ideal way to reduce risk.
This vulnerability assessment utilizes data from the National Center for Atmospheric Research (NCAR). The map represents the maximum average heat index through years 2011-2016.
Sensitivity
For this assessment, sensitivity refers to physiological, socio-economic and community design factors that increase susceptibility to extreme heat events. The assessment included a variety of indicators in this group, some of which have been highlighted here.
Percentage of Adults with Diabetes
When it comes to extreme heat, certain pre-existing conditions are important to consider. Medications for some conditions can cause individuals to become dehydrated more easily. Diabetes, for example, can impact the body’s ability to regulate temperature. For this reason, we have included the percentage of adults in Harris County with diabetes into this assessment. Other pre-existing conditions such as cardiovascular disease and asthma were also included.
65+ years of age
There are multiple factors that make older populations vulnerable to high temperatures. Older populations are more likely to have underlying health conditions like respiratory and cardiovascular illnesses that can be exacerbated by extreme heat. Additionally, older populations are more likely to take medications that can affect urination and their ability to sweat, which in turn can impact the body’s ability to cool and stay hydrated.
Older individuals may live alone which is a concern especially if they are socially isolated. The support of family, friends and caregivers is important during extreme heat events in providing essential items, access to health care services, and assistance with evacuation. This support could even be life-saving to some individuals living alone, such as older populations or those with disabilities. Social isolation has become even more a concern during the Covid-19 Pandemic because social distancing measures and stay at home orders have added extra challenges.
Outdoor Workers
Outdoor workers, like those that work in construction or agriculture, often have extended exposure to extreme heat and are therefore at higher risk of illness. These occupations often require lots of physical activity that can increase sweat production and lead to dehydration. The proper protective clothing and equipment often necessary for job safety and can also make the body hotter and reduce its ability to cool. Outdoor works should take frequent water breaks and seek air conditioning when possible.
No Health Insurance
Extreme heat can cause heat related illnesses that often require medical care. In other cities, extreme heat events have been associated with increased an increase in hospital admissions, emergency room visits, and emergency medical services calls. Studies have shown that populations without health insurance are less likely to seek health care, and if they do receive care will likely have the added stress of the health care costs. This may be more of a concern with increased unemployment due to the pandemic.
Adaptive Capacity
Adaptive Capacity is an evaluation of the ability to adjust, limit and cope with potential hazards or exposures. The adaptive capacity indicators chosen for extreme heat include access to air conditioning, access to cooling centers, and tree canopy coverage. Three indicators were chosen to represent adaptive capacity for extreme heat, but in general adaptive capacity can include access to financial resources and aid, government policies and programs, health infrastructure, access to technology, and access to natural resources.
Tree Canopy
Areas with limited tree canopy and lack of air conditioning will have lower adaptive capacity compared to areas with a high percentage of air conditioning and plentiful tree coverage. Air conditioning during extreme heat events is essential in reducing exposure and keeping people cool. Trees naturally provide shade and have cooling effects which is why they remain an important part of communities when temperatures rise.
Household Air Conditioning
Access is not a perfect measure and simply because people have access does not mean they are receiving benefits from that resource. For example, a household may have access to an air conditioning unit, but air conditioning isn’t used because the electricity costs are too expensive. While the measure is not perfect and it has limitations, it is the best data available at this time. For that reason, it has been included in this assessment.
Extreme Heat Solutions
Explore the assessment more
Click on each census tract to see the heat and health vulnerability score.
Heat Vulnerability Index 2021
