Warmer temperatures could endanger public health

By Amanda Phipps

phippsa@thejohnsonian.com

Populations that depend on snow for water may need to find a new method of water attainment thanks to climate change, which has resulted in warmer temperatures globally, geology professor Marsha Bollinger said.

Whether it is a normal change in weather or related to global warming, climate changes have resulted in a change in the timing of snow in certain areas that depends on snowmelt for their water supply, she said.

“We assume that when we go to a water fountain, water will be available and suitable for drinking,” she said, “but other parts of the world could be in trouble if the availability of water changes.”

Northern California currently has reservoirs that are engineered to catch snowmelt that will be used to supply water during dry periods, Bollinger said. 

The National Resources Conservation Service (NRCS) maintains a system to collect snow called SNOTEL (Snowpack Telemetry), which measures the snowfall in the western mountains and uses that information to forecast water supply, according to the NRCS website.

Places such as California, Washington and Oregon have already begun to experience a change in the amount and timing of snowfall, Bollinger said.

The conclusion is that climate change is causing this, but the question remains if this is normal climate change or change related to human-induced global warming, she said. 

Climate change may also affect the world’s food supply, she said. 

“Water impacts where plants grow,” she said. 

If there is a change in the amount of water an area gets, it may result in certain crops not being able to thrive there, she said. This can affect overall food supply and public health. 

Climate change can also affect rain patterns, which can brimg more water to dry areas of the world and less in areas that are used to having a steady water supply, she said. This causes a change in the distribution of water and can affect how people maintain a water supply. 

“We would have to adapt to it,” Bollinger said. 

People in certain areas may have to move elsewhere due to a lack of water because of global warming, political science professor Christopher Van Aller said. Certain countries will lose the availability of water if the time and amount of snowmelt changes due to warmer temperatures. These people may become environmental refugees and create overcrowding in refugee camps, further threatening public health. 

“Refugees are going to want to move to areas better for life,” he said, “but other countries are already there.” 

Psychology professor Jeffrey Sinn said most wars are fought over land and resources. As the arctic ice caps continue to melt, the problem will become figuring out who will own the oil beneath that area. 

If climate change makes some areas unable to support the same amount of resources and the populations continue to rise, tensions between territories may increase. 

“It will be a whole new level of chaos,” he said. “Countries will act in their own interest. We will not be together on this.” 

Climate change may also result in an increase of diseases, Van Aller said.  An increase in insect-spread diseases, such as malaria, may be a result of warmer temperatures, causing changes in water levels in certain areas. 

Climate change can lead to an increase of mosquitoes, which can carry malaria, because they thrive in warm weather, according to the Environmental Protection Agency (EPA) website. Insects can also spread other vector-born diseases, including yellow fever and dengue fever. 

Overcrowding of refugees can increase the spread of disease, Van Aller said. 

Diseases depend on insects, such as mosquitoes, for transmission between hosts, biology professor Paula Mitchell said. 

“The disease organism is usually transmitted in the saliva when the insect feeds on the host’s blood,” she said. 

Malaria is a disease that is caused by a protozoan and is evolutionarily tied to very few mosquito species, Mitchell said. The species will not thrive in temperate environments. 

“The disease organism cannot complete its development in the mosquito at low temperatures,” she said.

The vector that carries the disease in the mosquito and the mosquito itself will do better in warmer conditions, Mitchell said. This will result in an increased abundance of mosquitoes.

Global warming may result in an increase in temperature that will make the environment more tropical, and mosquito species will move from Central and South America to the U.S. and be able to populate and spread disease, Mitchell said. 

Dengue and yellow fever may also be able to spread with the increases in temperature, causing more regions to be able to hold the vector Aedes aegypti, a mosquito species that carries the disease, she said. 

Extreme temperatures can directly result in global loss of life, according to the EPA website. Changes in climate can cause ecological disturbances, such as “changes in the range of infective parasites,” which can indirectly impact health through the spreading of disease. Warm temperatures can also harm public health through an increase in air and water pollution. 

Van Aller said some benefits exist to climate change, but each one also affects something else. Certain areas normally too cold for crops to grow may become available, and longer growing seasons may be a result of climate change, but other areas will be affected.

“You can’t pretend that changing one massive thing will have no other effects,” he said. 

Van Aller said the problem with global warming is that it causes change too quickly.

“It takes a long time for a biological system to adapt to a new environment,” he said. “If it changes too quickly, it can have adverse effects.”

Sinn said it’s hard to tell exactly what climate change will result in. 

“There has never been this big of a shift (in environment) in human history,” he said. “It’s hard for social scientists to predict what’s going to happen.”