Human-caused climate change is triggering increasingly extreme weather. Greenhouse gases from the combustion of fossil fuels are making much of our planet hotter and wetter. Temperatures have been increasing steadily since the 1980s, and we are now experiencing more severe heat waves, fiercer wildfires, wilder hurricanes, heavier floods, and drier droughts.1,2 Scary terms like “bomb cyclone,” formerly the jargon of meteorologists and weather geeks, have become mainstream as these weather events occur more frequently.
How does climate change create extreme weather?
Extreme weather is climate change in action.3 Warmer air can hold more moisture than colder air, so a warmer atmosphere means stronger storms that can release record rain and snowfall.4 Drought can be intensified, as higher temperatures boost evaporation and precipitation patterns change.5 Higher temperatures are also making wildfire season longer and more intense as well as causing seawater to expand and glacial ice to melt.6 This is leading to rising sea levels, which can trigger storm surges, erosion, and flooding.7
What are the impacts of extreme weather?
Extreme weather touches every facet of our lives. More and more of us are experiencing these impacts in our own communities: in 2021, more than 4 in 10 people in the US lived in counties hit by climate disasters.8
Trees, which help mitigate climate change by removing carbon dioxide from the air and storing it, burn down in wildfires or uproot in floods.9 Firefighters tackle increasingly dangerous work, and wildfire smoke is harmful for all to breathe.10 Storm cleanup is staggeringly expensive for governments, communities, and individuals.11
Extreme weather has social costs too. Food can be harder to grow, drinkable water is scarcer,12 and job and housing security lessen. In some areas, these impacts make it unsafe to live, forcing people to flee their homes and migrate to safer areas.13
How does extreme weather harm human health?
Extreme weather can impact our health in a wide variety of ways. Extreme heat has been linked to increased hospital admissions for respiratory and heart problems. Heat waves exacerbate air pollution, which in turn can result in asthma attacks, increased vulnerability to infections, and even lung cancer, heart attacks, and stroke.14 Wildfire smoke contains fine particle pollution, also known as PM2.5 or soot, which is a leading cause of premature death worldwide.15 Air pollution is especially dangerous for babies, children, and the elderly.16
Heavy rainfall and storm surges can increase the transmission of diseases, including malaria. Mold and contamination are of concern in flooded homes, schools, and other built environments.17 Drought can impact drinking water, agriculture, and air quality too. And extreme weather disasters like hurricanes and wildfires are linked to depression, anxiety, trauma, and other mental health impacts.18
An Extreme Weather Glossary for Modern Times19
In a changing climate, many of the words used to describe intensified weather are familiar: hurricane, wildfire, and drought. But there are also new and weird meteorological terms and phenomena. Here are a few:
There’s no such thing as an ARkStorm—yet. It’s part of a US Geological Survey research project, a made-up megastorm scenario that could do unheard-of damage, similar to historical storms but with magnitudes and frequency intensified by climate change. The intentionally biblical name is an acronym blending “atmospheric river,” k (which stands for 1,000, because ARkStorm was projected as a 1-in-1,000-year event), and “storm.”
These air currents are long, concentrated regions in the atmosphere that transport moist air from the tropics. According to NOAA, rivers in the sky can be beneficial to regional water supply but can also release heavy wind, rain, and snow. In areas experiencing drought, they can cause flash floods, mudslides, and destruction of life and property.23
Bombogenesis (aka bomb cyclone) is when a cold air mass collides with a warm air mass, such as air over warm ocean waters. The National Ocean Service says these mid-altitude cyclones intensify quickly and can result in extreme rain or snow.24
Fire tornadoes are rare, occurring when wildfire heat creates its own wind system. Also called pyrogenetic tornado, fire whirl, and fire devil (experts debate the nuances of these terms), these tornado-like bursts rise from a fire, polluting the air with smoke and debris. Some can be more than 500 feet in diameter.
Climate change is currently impacting drought all over the world. Still, historical megadroughts, aka prolonged drought lasting for decades, have been documented, including some that took place thousands of years ago.26
The National Weather Service says this large area of low pressure and cold air surrounding both of Earth’s poles is not new. Still, climate change has impacted polar vortex behavior and can cause expansion to southern latitudes.29,30 “Vortex” refers to the counterclockwise airflow that keeps colder air near the poles. It’s weaker in summer and stronger in winter and is associated with outbreaks of arctic air in the US.
Make your voice heard
A sustainable and resilient future comes down to strong climate policy. We need laws and policies that can help our communities adapt to climate-driven extreme weather and reduce the causes of climate change. Urge your representatives to act on climate today.
Released: February 2023