Climate & Health 101

Climate vs Weather

To understand how climate impacts health, you first need to know what climate is. Climate and weather are different.

Weather refers to short periods of time, days or weeks and is what is happening outside right now. Weather influences the clothes you wear each day. If it’s raining outside you may pull out rain boots and a raincoat to keep dry.

Climate represents long periods of time and is the weather you expect at certain times of the year. Climate influences the type of clothes you have in your closet.


For example, your closet would look very different if you lived in Houston compared to New York. If you lived in Houston your closet may be filled with shorts and sandals because you expect it to be warm all year; However, if you lived in New York you would have a winter coat and snow boots because you expect cold weather and snow

What is climate change?

Climate Change is the long-term change of the climate. This occurs because certain gases in the atmosphere prevent the sun’s heat from escaping; which is called the greenhouse effect. When sunlight reaches the earth’s surface, it can be absorbed into the atmosphere or reflected into space. Greenhouse gases such as water vapor, carbon dioxide, methane, and nitrous oxide, trap the sun’s heat inside Earth’s atmosphere. As more heat is trapped, Earth’s air and oceans get warmer and create a domino effect. The increasing temperatures affect other climate elements like precipitation patterns and sea level. As the climate changes, the weather will change, the atmosphere will get warmer, and eventually people and health are impacted.


How Climate Impacts Health

Climate change impacts can cause injuries and death, worsen pre-existing conditions such as asthma, create mental health problems, and more. Some health impacts are a direct result of the changing climate while others are indirect.

Heat stroke is an example of a direct impact of extreme heat. Rising temperatures lead to more extreme heat days with high temperatures and high humidity. This can increase heat exposure leading to heat stroke or heat exhaustion. In this case, the high temperature itself causes negative health outcomes making it a direct impact.

Hurricanes and mental health are a good example of indirect impacts. Hurricanes and major flood events can destroy homes and infrastructure and lead to loss of homes and belongings. Families must leave their homes, cope with the loss of personal belongings, and some may have to stay in shelters which can cause indirect health impacts like increased stress and anxiety.


Climate and Health Solutions

Climate solutions are grouped into two categories: adaptation and mitigation.

  • Mitigation refers to methods that reduce greenhouse gas emissions and prevent the Earth from warming more. Policy changes to decrease emissions and increase walking, biking, and public transit are examples of efforts to mitigate greenhouse gas emissions.
  • Adaptation refers to individual, community and government actions to reduce the negative impacts of climate change and increase the ability withstand the changes in the climate. Heat response plans, tree planting, updated infrastructure, improved flood control, public health messaging and financial assistance are some examples of potential adaptation strategies.

Our Initiatives

For information about how climate and health directly impact our community, explore the initiatives that the Climate Program has planned - including those around heat, air quality, and flooding.


The risk profile project is comprised of two parts— a vulnerability assessment and disease burden projections. These two components are also the first two steps in the CDC’s Building Resilience Against Climate Effects (BRACE) Framework. The risk profiles are essential for creating a strong foundation for future climate work. They allow for the prioritization of vulnerable communities and the targeting of climate impacts to better customize engagement and implementation activities. In addition, they provide HCPH with local references and statistics to communicate and advance our climate and health mission.



The vulnerability assessments examine certain climate impacts and the corresponding health effects they have on communities. They identify which communities are most vulnerable, allowing HCPH to concentrate public health interventions (e.g. community outreach, cooling center placement and nature-based solutions) in areas that need them most. The current vulnerability assessments are focused around extreme heat, flooding and air quality. In the future the focus will expand to include other climate concerns and explore the interactions between multiple climate impacts.


Disease burden projections combine climate change projections and current climate-related disease data to produce estimates of disease burden under future climatic scenarios. With funding from the National Association of County and City Health Officials (NACCHO) and the CDC, HCPH will collaborate with Houston Advanced Research Center (HARC) to begin the disease burden projections for extreme heat.