Chesapeake PSR

Climate Change and Health

Scientists agree: Global temperatures are rising, causing more variable and extreme weather, more flooding and drought, more common heat waves and fire, and the spread of new and existing vector-borne disease. This "new normal" is already here, with the many impacts of climate change on health increasingly being recognized. 

Climate change's effects on health

The entire globe faces a dramatic change in environmental conditions that will differ from region to region. In Maryland, major health impacts are likely from sea level rise and more severe storms because of warming oceans and an increasingly humid atmosphere. In urban areas, people will suffer from higher temperatures.

Changes we can expect in Maryland

More severe and extreme weather

Storms and flooding will likely be very problematic, given Maryland's extensive coastline. Hurricanes and other coastal storms gain energy from the warming ocean, and rising temperatures cause air masses to hold more water, making storms more severe. For every 1°C increase in air temperature, the frequency of storms as damaging as Hurricane Katrina is expected to increase by 200-700 percent. Severe storms bring many and long-lasting health impacts, including:

  • Injuries from damaging winds, flying debris and flooding Damage to hospitals or other infrastructure may interfere with proper treatment of wounds.

  • Illnesses and infections from contaminated floodwaters - As floodwaters spread across wide areas, dangerous chemicals or pathogens distributed by floodwater can contaminate drinking water, recreational waterways, food crops, stored food and fish or shellfish stocks. Floodwaters may promote infection. In Maryland, flooding on the Eastern Shore has been linked with an increased frequency of intestinal illnesses.(2)

  • Exposure to sewage from flooded or overwhelmed sewage treatment systems - Flooding of overwhelmed or older sewage plants releases large quantities of sewage into waterways, spreading pathogens, contaminating drinking and recreational water, and infiltrating homes. During Hurricane Sandy, 84 million gallons of raw or partially treated sewage was released into Maryland waterways.(6)

  • Human injury and disease from increased exposure to rodents and other animals - Exposure to animals uncovered by floodwaters increases the potential for the spread of disease.

  • Aggravated asthma and other respiratory problems from mold and mildew growth in walls and furniture - After floodwaters retreat, damp conditions foster mold and mildew growth in homes and worsen asthma and respiratory issues. Floodwaters laden with bacteria and toxins also may contaminate furniture and possessions. 

  • Illness, anxiety and social unrest from destruction of homes - Large-scale displacement, illness, and social disruption may result from destruction of homes, as documented after Hurricane Katrina in New Orleans, where looting and violence were reported, as well as inadequate food and sanitation in shelters.

  • Psychological trauma from the scale of damage and loss - Psychological fallout from such an event may impede individual and community recovery. Effects on young children may be particularly pronounced and long-lived.(7)

  • Prevention of care or access to medicines because of damage, loss of power or flooding in hospitals - Hospital damages and evacuations may prevent the chronically ill or injured from obtaining necessary care and medicines.

  • Reduced access to food and medicine because of damage to transportation systems - Damage to transportation systems or infrastructure may interfere with access to food and medicine and prolong the recovery period.

Dramatic increases in routine tidal flooding

Sea level rises in coastal regions and Chesapeake Bay communities will cause high tides to wash over low-lying areas more often. Among the nation's most flood-prone cities, Baltimore, Washington, D.C., and Annapolis will each experience a dramatic increase in floods by 2030 (chart). 

Longer and more severe heat waves

Heat is a serious problem in urban areas, where temperatures can be 5-8°F warmer than in suburban areas. Heat stress is particularly serious for children exercising outdoors, the elderly, those without air conditioning and outdoor workers. Early stages of heat stress easily can be confused with fatigue. If ignored, heat stress can lead to coma and even death.

An increase in toxic algal blooms

Toxic algal blooms caused by warming river and coastal waters could contaminate drinking water and harm seafood. [LS: One sentence or clause - Where does it come from, why does this matter - make people sick with xxxx, how does it harm seafood?]

More droughts

As temperatures warm and weather becomes more variable, the mid-Atlantic will experience periodic drought, affecting Maryland agriculture and adding to the risks of water and food insecurity. Under dry conditions, toxins and pathogens can become concentrated in recreational waterways [LS: and drinking water reservoirs], increasing health risk. Drought and heat together also greatly increase the risk of heat stress.

Poorer air quality and higher pollen counts

As ozone production increases during hot weather, particulates from fires will blow through Maryland and aggravate the already serious asthma problem, and add to the risk of other respiratory disease, heart attack and stroke. [LS: sentence re aerial pollen concentrations - why and what it causes]

More insect-borne diseases

The geographic areas of insect vectors of disease are widening as temperatures get warmer. Lyme disease is spreading in our region as the ticks that spread it overwinter in greater numbers. The insect vectors that spread diseases like Dengue fever, malaria and chikangunya increasingly are found in the U.S., including the mid-Atlantic. [LS: Mention Zika?]

Greater risk to vulnerable populations

The effects of a changing environment will touch all segments of society, but the largest impacts of climate change are likely to fall on Maryland's children, elderly, chronically ill, outdoor workers, and those with low incomes and/or limited education. For these populations, climate change can multiply the many health risks already present.

Chesapeake PSR supports climate-friendly policies that protect public health

We support policies that will increase the use of clean, renewable energy, reduce greenhouse gas emissions and promote energy efficiency. We would like to see coal and other dirty energy sources eliminated from the state's energy mix by 2050. Cleaner energy will not only limit climate change but will have measurable positive effects on cardiovascular and respiratory health. We also support policies that will help communities adapt to problems that are now unavoidable, such as the impacts of sea level rise on flooding. A public health response to climate change will ensure that climate policies work to protect the heath and well-being of our families and communities.


The effects of climate change are being felt today, and figure projections represent an unacceptably high and potentially catastrophic risk to human health.
- The Lancet Report on Clmate Change and Health


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