The year 2022 will be remembered across the U.S. for its devastating flooding and storms – and also for its extreme heat waves and droughts.
By October, the U.S. had already seen causing more than US$1 billion in damage each, well above the average. The year started with widespread severe winter storms from Texas to Maine, affecting tens of million of people and causing significant damages. Then, March for the most reported in the month – 233.
During a period of five weeks over the summer, occurred in , , , California’s and , causing devastating and sometimes deadly flash floods. Severe flooding in Mississippi for weeks. A , brought on by heavy rain and melting snow, forced large areas of Yellowstone National Park to be evacuated.
In the fall, and deluged Florida and Puerto Rico with over 2 feet (6.6 meters) of rain in areas and deadly, destructive storm surge.
Ian became hurricanes in U.S. history. And a 1,000 miles (1,600 km) of the Alaska coast.
While too much rainfall threatened some regions, extreme heat and too little precipitation worsened risks elsewhere.
Persistent heat waves lingered over many parts of the country, setting temperature records. Wildfires raged in and on the background of a more severe than anything the region has experienced in at least 1,200 years.
Drought also left the Mississippi River so low near Memphis in the fall that barges couldn’t get through without additional dredging and upstream water releases.
That snarled grain shipping during the . Along the Colorado River, officials discussed even tighter water use restrictions as in the major reservoirs.
The United States was hardly alone in its climate disasters.
In Pakistan, inundated more than one-third of the country, killing over 1,500 people. In and , prolonged heat waves and droughts dried up rivers, disrupted power grids and threatened food security for billions of people.
Widespread flooding and mudslides brought on by torrential rains also killed hundreds of people , and .
In Europe, heat waves set record temperatures and other parts of the continent, leading to severe droughts, , and wildfires in many parts of the continent. Much of East Africa is still in the grips of a multiyear drought – the , according to the United Nations – leaving millions of people vulnerable to food shortages and starvation.
This isn’t just a freak year: Such extreme events are occurring with increasing frequency and intensity.
Climate Change is Intensifying These Disasters
The most from the United Nations Intergovernmental Panel on Climate Change found significant increases in both the frequency and intensity of extreme temperature and precipitation events, leading to more droughts and floods.
Extreme flooding and droughts are also getting deadlier and more expensive, despite an improving capacity to manage climate risks, a study published in 2022 found.
Part of the reason is that today’s extreme events, enhanced by climate change, often exceed communities’ management capabilities.
Extreme events, by definition, occur rarely. A 100-year flood has a 1% chance of happening in any given year. So when such events occur with increasing frequency and intensity, they are a clear indication of a changing climate state.
Climate Models Showed These Risks Were Coming
Much of this is well understood and consistently reproduced by climate models.
As the climate warms, a shift in temperature distribution leads to more extremes. For example, globally, a 1 degree Celsius increase in annual average temperature is associated with a 1.2 C to 1.9 C (2.1 Fahrenheit to 3.4 F) .
In addition, global warming leads to changes in how the atmosphere and ocean move. The temperature difference between the equator and the poles is the driving force for global wind.
As the polar regions warm at much higher rates than the equator, the reduced temperature difference causes a weakening of global winds and leads to a .
Some of these changes can create conditions such as persistent high-pressure systems and atmospheric blocking that bring more intense heat waves. The heat domes over the Southern Plains and South in June and in the West in September were both examples.
Warming can be further amplified by positive feedbacks.
For example, higher temperatures tend to dry out the soil, and less soil moisture reduces the land’s heat capacity, making it easier to heat up. More frequent and persistent heat waves lead to excessive evaporation, combined with decreased precipitation in some regions, causing more severe droughts and more frequent wildfires.
Extreme Storms Get Wetter as Temperatures Rise
As temperatures rise, the intensity of storms increases, the IPCC's latest assessment report shows. The chart shows how much wetter heavy one-day storms that historically occurred about once every 10 years are likely to become as temperatures rise.
Higher temperatures to hold moisture at a rate of about 7% per degree Celsius. This increased humidity leads to heavier rainfall events.
In addition, storm systems are – the large amount of energy released when water vapor condenses to liquid water. Increased moisture content in the atmosphere also enhances latent heat in storm systems, increasing their intensity. Extreme heavy or persistent rainfall leads to increased flooding and landslides, with devastating social and economic consequences.
Even though it’s difficult to link specific extreme events directly to climate change, when these supposedly rare events occur with greater frequency in a warming world, it is hard to ignore the changing state of our climate.
The New Abnormal
This year might provide a glimpse of our near future, as these extreme climate events become more frequent.
To say this is the “new normal,” though, is misleading. It suggests that we have reached a new stable state, and that is far from the truth. Without serious effort to curb greenhouse gas emissions, this trend toward more extreme events will continue.
This updates an article on Sept. 21, 2022.
(Shuang-Ye Wu is a Professor of Geology and Environmental Geosciences, University of Dayton. Shuang-Ye Wu does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.)
(This is an opinion piece and the views expressed above are the author’s own. The Quint neither endorses nor is responsible for the same. This article was originally published on The Conversation. Read the original article here.)