2022’s US climate disasters, from storms and floods to heat waves and droughts

2022 will be a memorable year across the nation with devastating floods and storms, extreme heat waves and drought.

By October, the United States had already experienced 15 disasters, each with more than $1 billion in damage, well above average. The year began and ended with severe winter storms that swept across Texas and Maine, affecting tens of millions of people and causing significant damage. March then set a monthly record for the most reported tornadoes, 233.

During five weeks of summer, five 1,000-year rainfall events occurred in St. Louis, eastern Kentucky, southern Illinois, Death Valley in California, and Dallas, causing devastating and sometimes fatal flash floods. Severe flooding in Mississippi cut off Jackson’s water supply for weeks. Massive areas of Yellowstone National Park have been evacuated due to Montana’s historic flooding brought on by heavy rains and melting snow.

In the fall, Hurricanes Ian and Fiona hit Florida and Puerto Rico, bringing over 2 feet (6.6 meters) of rain and deadly and devastating storm surges. Ian became one of the most expensive hurricane girlfriends in US history. And a typhoon hit her 1,000 miles (1,600 km) off the Alaskan coast.

Too much rain has threatened some regions, while extreme heat and too little rain have exacerbated the risks in others.

A persistent heat wave lingered in many parts of the country, setting record temperatures. Wildfires raging through Arizona and New Mexico are the worst the region has seen in at least 1,200 years, against the backdrop of a massive drought in the southwestern United States.

The drought also made the Mississippi River so low in the fall near Memphis that barges could not pass without additional dredging and water discharge upstream. Along the Colorado River, water levels in major reservoirs have approached dangerously low levels, prompting officials to discuss even tighter restrictions on water use.

The US was not alone in the climate disaster.

In Pakistan, record monsoon rains have flooded more than a third of the country, killing more than 1,500 people. In India and China, persistent heatwaves and drought have dried up rivers, disrupted power grids and threatened food security for billions of people. Hundreds have also died in South Africa, Brazil and Nigeria due to widespread flooding and landslides caused by heavy rains.

In Europe, a heatwave set record temperatures in the UK and other parts of the continent, leading to severe drought, reduced river flow that slowed transportation, and wildfires in many parts of the continent. . Large parts of East Africa are still suffering from a multi-year drought, according to the United Nations, the worst in more than 40 years, leaving millions of people without food or starving. are at risk of

This year is not an anomaly. Such extreme events are occurring with increasing frequency and intensity.

Climate change is exacerbating these disasters

The latest global climate assessment by the United Nations Intergovernmental Panel on Climate Change found that both the frequency and intensity of extreme temperatures and precipitation events have increased significantly, leading to more droughts and floods.

A study published in 2022 found that extreme floods and droughts are becoming more deadly and costly despite our growing ability to manage climate risks. Part of the reason is that today’s extreme events, enhanced by climate change, often exceed the capacity of communities to manage.

By definition, extreme events are rare. The probability of a 1-in-100-year flood is 1% in a year. So when such events are occurring with increasing frequency and intensity, they are a clear indication that climate conditions are changing.

Climate models showed these risks were coming

Much of this is well understood and consistently reproduced by climate models.

As the climate warms, changes in temperature distribution lead to more extreme conditions. For example, globally, a 1 degree Celsius increase in average annual temperature would result in a 1.2 to 1.9 degree increase in maximum annual temperature (2.1 to 3.4 degrees Fahrenheit).

Global warming will also change the movements of the atmosphere and oceans. The temperature difference between the equator and the poles is the driving force behind the world’s winds. Polar regions warm at a much faster rate than the equator, so a reduction in temperature differentials weakens the global winds and makes the jet stream more meandering.

Some of these changes could create conditions such as persistent high-pressure systems and blockages of the atmosphere, resulting in more intense heatwaves. The Southern Plains and Heat Domes of June and his Western Heat Domes of September were both examples.

Warming can be further amplified by positive feedback.

For example, high temperatures tend to dry out the soil, and low soil moisture reduces the heat capacity of the land, making it easier to heat. More frequent and sustained heatwaves, combined with less precipitation in some areas, will lead to excessive evaporation, leading to more severe droughts and more frequent wildfires.

Warmer temperatures increase the water-holding capacity of the atmosphere by about 7% per degree Celsius. This increase in humidity will lead to more intense rainfall events.

Additionally, storm systems are powered by latent heat, a large amount of energy released when water vapor condenses into liquid water. An increase in atmospheric moisture content also increases the latent heat of the storm system, increasing its strength. Extreme and sustained rainfall will lead to increased flooding and landslides, with devastating social and economic impacts.

While it is difficult to directly link specific extreme events to climate change, it is difficult to ignore the changing state of climate when these supposedly rare events occur more frequently in a warming world.

new anomaly

With these extreme climate events occurring more frequently this year, we may be able to catch a glimpse of the near future.

But to say this is the “new normal” is misleading. This suggests that we have reached a new state of stability, which is far from the truth. Without serious efforts to curb greenhouse gas emissions, this trend will continue toward more extreme phenomena.

Shuang-Ye Wu is Professor of Geology and Environmental Geosciences at the University of Dayton.

This article is republished from The Conversation under a Creative Commons license. Please read the original article.