Climate change drives extreme weather patterns, creates new obstacles for Missourians
Heatwaves, drought and heavy downpours are some of the main ways people encounter climate change. These extreme weather and climate events are becoming increasingly more common across the United States.
According to the National Climate Assessment, “over the last 50 years, much of the U.S. has seen increases in prolonged periods of excessively high temperatures, heavy downpours, and in some regions, severe floods and droughts.”
In addition, while the frequency and intensity of extreme weather events increases, the financial cost of such events is increasing as well. In 2020, there was a record breaking 22 climate-related disasters where overall damages exceeded $1 billion across the United States. This is much higher than the previous yearly average of 16 climate-related disasters, seen both in 2017 and 2011.
What does this mean for Missouri?
Missouri is affected by extreme heat, droughts, intense rainfall, flooding and severe weather events like tornadoes, high winds, thunderstorms and ice storms.
Throughout the Midwest, the National Climate Assessment found that the state of people’s health will decrease across the board due to the “frequency and intensity of poor air quality days, extreme high temperature events, and heavy rainfalls.”
Here is a look at a couple of the extreme weather patterns that are being exhibited throughout Missouri and how these events are exacerbated by climatic fluctuations.
Doug Kluck, the National Oceanic and Atmospheric Administration Regional Climate Services Director for the Central Region, said that Missouri is seeing more occurrences of heavy rainfall events and less moderate or light precipitation events.
“We’re sort of bending the curve of probabilities towards greater chances for heavy and/or extreme precipitation events,” Kluck explained.
This increase in heavy rainfall comes from the warmer air, which is able to hold more moisture to be available for storm systems to use as fuel. This prevalence of warmer air in the atmosphere is then responsible for igniting heavy bouts of rainfall.
Heavy rainfall can lead to infrastructure issues, flooding, flash-flooding and saturated soil, which leads to soil erosion and the potential loss of crops for farmers.
Due to heavier rainfall, flooding in Missouri has increased. High runoff from the Missouri, Mississippi and Meramec rivers has caused long-term flooding of the flood plains, threatening more than 220,000 people in Missouri who are living in areas at elevated risk of inland flooding, according to States at Risk.
Flash floods have also become more common. For example, in December 2015, more than 9 inches of rain hit the ground in St. Louis causing flood waters to breach a sewage treatment plant and overflow at least 100 million gallons of sewage into rivers and streams nearby, polluting the water and endangering local communities’ health.
“The amount of paved surfaces in metropolitan areas have prevented the kind of natural absorption of rainwater that might otherwise have occurred,” Andrew Hurley, professor of environmental history at the University of Missouri-St. Louis said.
Missouri farmers are especially at risk of the effects of flooding. In 2019, due to the Missouri River bursting its banks, farmers were prevented from planting millions of acres of crops.
Although springtimes are getting wetter, it is predicted that summer droughts will be more severe due to climate change. Climate change causes warmer temperatures that can enhance evaporation from soil, making periods with low precipitation drier than they would be in cooler conditions.
“The variability of extremes seems to have increased,” Kluck said. “In other words, we’re tending to get more and more really low or really high levels of precipitation.”
Drought impacts farmers when they have to spend more money to feed animals, water crops and also when yields are destroyed entirely by unpredictable weather events. People and animals depend on water as well, and drought can shrink food supplies and as well as animals’ habitats.
According to NOAA, “sometimes this damage is only temporary and other times it is irreversible.”
In other words, the longer the drought, the more detrimental the effects.
Missouri’s hot and humid summers can prove dangerous for residents simply from a health perspective. With the added effects of climate change, this problem will only get worse over time.
According to the Union of Concerned Scientists, “at the current rates, every summer in Missouri toward the end of the century is projected to be as hot as or hotter than 1980 — Missouri’s hottest summer of the last half century.”
These hot temperatures pose strong threats to public health and the agricultural industry. According to the EPA snapshot on what climate change means for Missouri, hot weather could cause cows to eat less, produce less and grow slower and hotter summers could reduce yields of corn unless there is adequate water available.
As far as increases in extreme weather events due to climate change go, the correlation is less clear.
“There hasn’t been a conclusive finding to say that we’re having more or less of those over time,” said Kluck, in reference to extreme weather and storm events like tornadoes, high winds and hail.
But the increasing humidity in the atmosphere promotes atmospheric instability, allowing for intense storms to percolate.
“When some kind of storm does come through, you can really wring out a lot more water at once,” Kluck said. “It’s the combination of temperature and precipitation that really causes the problem.”