How Climate Change Fueled This Summer’s Record-Setting Extreme Weather

Oct 5, 2023

This summer saw thousands of climate records shattered as extreme weather events and disasters devastated communities around the world. It seems nowhere is safe from the continuous barrage of devastating and deadly extreme heat, fires, storms, and floods that have destroyed towns and communities and stolen lives on every continent.

Image of wildfire. Text reads, "2023: A Summer of Extremes."
Check out our video on extreme weather on our social channels.

The unprecedented scale of “natural” disasters we witnessed this summer is a direct result of the climate crisis. Here’s a closer look at how climate change contributed to extreme weather events around the globe over the past few months.

In this article:

Global Extreme Weather Events from May to September 2023

Extreme heat spreads as the global temperature hits record highs

Record-shattering heat is the result of ever-increasing levels of carbon in the atmosphere, and is one of the most widely understood (and felt) impacts of climate change. Over the summer, millions of people in communities around the world were confronted with extreme heat. Lack of infrastructure and resources made these heat waves debilitating, and even deadly, for impacted communities, especially those who have been historically excluded.

A chart showing increasing summer temperatures in the Northern Hemisphere from 1830-2021.
Credit: Ed Hawkins; Source: Scientific American

Statistics show that extreme heat has killed more people in the U.S. than any other weather phenomenon. Prolonged exposure to extreme heat can also cause dehydration, heat stress and heat stroke, and can exacerbate existing cardiovascular and respiratory conditions. Extreme heat also takes a costly toll on our physical infrastructure, melting roads, warping rails, and forcing fossil fuel refineries and dirty power plants to curtail their output or production.

Millions of people worldwide experienced the impacts of record-breaking heat events over the past few months, including:

  • The hottest month on record: July 2023 was the hottest month ever recorded with the global average temperature being 15.8°C (60.4°F), which is 1.12°C (2.02°F) above 20th century average.
  • The hottest three days ever recorded: July 3-6 were the hottest days on record globally, with July 6, 2023 being the hottest day ever recorded, checking in with a global average of 17.23°C (63.02°F).
    • Further heat records were broken in Catalonia, Spain; Verdun, France; and Rome, which all experienced their highest temperatures on record on July 16. On the same day, an airport in Iran saw a heat index of 66.7°C (152°F).
  • A deadly heat wave in India that resulted in 170+ heat related deaths.
  • Prolonged heat waves across Europe, China and the U.S., with Phoenix, Arizona experiencing a 31-day streak of temperatures exceeding 110°
  • The “worst drought in decades” in Chile and across the Horn of Africa.

The extreme heat we saw this summer is just a preview of what’s to come unless serious action is taken to reduce planet-warming emissions.

Wildfires worsened by dry conditions and high winds

Extreme heat on top of the drier land and air many regions are experiencing due to climate change is a dangerous combination that sets the stage for increasingly frequent and more intense wildfires.

A wildfire burns in Simi Valley, California.
A wildfire burns in Simi Valley, California. Credit: U.S. Air Force

This summer, some regions also experienced higher-than-normal winds generated by changing weather patterns and other storms. High winds caused wildfires to spread further and faster, ultimately making them even more destructive. Since May, we’ve seen:

  • The deadliest wildfire in the U.S in over a century on the island of Maui in Hawai’i. Prolonged drought in Maui, and strong winds from Hurricane Dora which passed Maui to its south, exacerbated the deadly blaze. The current death toll in Maui stands at 98, and several people remain missing or in critical condition nearly two months after the fire.
  • The EU saw its largest wildfire on record in Greece. The fire prompted the evacuation of over 20,000 people, severely damaged over 100 homes and businesses, and killed 28 people. A prolonged heat wave across Europe and unusually high winds in the area fueled the wildfire.
  • Canada experienced its worst wildfire season on record, which has burned over 70,000 square miles since May. Even as the country’s typical wildfire season would be winding down, hundreds of fires continue to burn across Canada, and experts estimate they will continue to burn until Canada gets heavy snowfall. The fires have displaced tens of thousands of Canadians, and entire Indigenous communities, and resulted in historically poor air quality across the U.S.

Devastating storms fueled by rising air and water temperatures

Global weather patterns that create storms are disrupted by rising air and water temperatures, exacerbating storm frequency and intensity.

Vermont’s state capital in the aftermath of “historic”, “worst in a century” floods earlier this summer.
Vermont’s state capital in the aftermath of “historic”, “worst in a century” floods earlier this summer. This flooding occurred only a decade after Vermont was inundated with flooding from Hurricane Irene, which damaged over 200 bridges. Credit: U.S. Air National Guard photo by Senior Master Sgt. Michael Davis

Storms fueled by changing weather patterns set records throughout the summer and had devastating impacts on millions of people. In June, for the first time in recorded history, each of the five ocean basins where tropical storms typically form produced a Category 5 hurricane. Also in June, two tropical storms formed in the Atlantic, another phenomenon never before recorded. Some major storms of the summer include:

  • Cyclone Mocha which hit Myanmar and Pakistan in May was one of the most powerful storms to ever impact the region with winds reaching 155 mph. Months later, residents are still dealing with the impacts of the storm that destroyed their homes and the crops they relied on for food. Stagnant water in many areas has become a breeding ground for bacteria, making people sick and sending many to hospitals that are already overcrowded with patients suffering illnesses related to prolonged extreme heat in the region.
  • Typhoon Mawar, which made landfall in Guam as a Category 4 storm, making it the most powerful storm the U.S. territory has seen in 20 years.
  • Deadly tornadoes tearing through Mississippi.
  • Powerful monsoons striking India, killing at least 100 people.
  • Hurricane Hilary, which became the first hurricane to hit southern California in 84 years when it made landfall in Mexico and the southwest U.S.
  • Historic flooding in Vermont and Kentucky. The floods in Vermont have been dubbed “the worst in a century” and Kentucky broke its daily rainfall record when Graves County received 11.28 inches of rain over a 24-hour period.
  • Widespread and record-breaking flooding in the Mediterranean. Just a few weeks after the wildfires were put out, Greece, Bulgaria, and Turkey were inundated with severe rainstorms that caused widespread flooding. The Greek village of Zagora, received 30 inches of water in a single day. Flooding across the region killed at least 15 people and forced the evacuation of hundreds of others.
    • After sweeping through Greece, Bulgaria, and Turkey, the same storm system reached Libya, where it caused further catastrophic flooding. The floods, which were made 50x more likely to occur due to human-caused climate change and brought a national record-setting 16 inches of rain in a single day to some parts of the country, devastated the city of Derna, destroying neighborhoods and killing thousands. The storm is estimated to be the deadliest storm to ever hit the Mediterranean and the most expensive storm to ever impact Africa.
  • Deadly flooding in Mexico, where at least seven people were killed in the state of Jalisco as the Jalocote river overflowed.
  • Hurricane Idalia, which made landfall in Florida as a high-end Category 3 hurricane with 125 mph winds. It then swept through Georgia and the Carolinas, where it spurred a tornado that touched down in a Charleston suburb. Four people died in the hurricane.

What can I do?

These stories and statistics are startling, but we cannot allow the fear and devastation brought by extreme weather to cloud our vision for the future. It looks scary now, but the future looks a whole lot scarier if we don’t take action.

It is possible to cut the planet-warming emissions that drive climate change, all while advancing a cleaner and more just future. And while the climate crisis is a global issue, the actions we take here in the U.S. and at home can have profound benefits for the entire world.

In Washington, D.C. and across the country with our state affiliates, LCV is advocating for policies that will help cut emissions by setting strong limits on:

  • Methane emissions from the oil and gas industry,
  • Toxic air pollution from power plants,
  • Air pollution in our communities, and
  • Tailpipe emissions from trucks and cars.

As we work to cut harmful pollution, we’re also working toward a transition to clean energy across the country by advocating for federal and state commitments to:

  • Invest in clean wind and solar energy.
  • Facilitate the transition to electric vehicles, including passenger vehicles and school buses.
  • Build a green economy with good jobs in clean energy and manufacturing.
  • Prioritize environmental justice for the communities of color who often bear the brunt of the climate crisis and associated pollution.

The Biden administration’s affordable clean energy plan, and its cornerstone Inflation Reduction Act (signed into law one year ago), is already making enormous headway on these goals with its more than $369 billion in clean energy project investments, as well as rebates and tax incentives for individuals, schools, towns, and businesses to invest in clean energy updates for their homes, buildings and vehicles.

While we’ve made great strides, the fight continues. You can join by:

  • Telling your members of Congress to support the Freedom to Vote Act, so voters can freely and fairly elect leaders who will prioritize environmental health and safety.
  • Learning how to tap into benefits under the affordable clean energy plan.
  • Taking advantage of tax incentives to go green at your home or business.
  • Pushing the Department of Transportation to advance cleaner cars.
  • Adding your name to more of our online actions.
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