Over the past week, floods, heat waves and wildfires across the United States have killed dozens of people and reshaped entire communities from Kentucky to northern California.
Why is this important: This summer has demonstrated time and time again that our infrastructure is not enough to withstand today’s changing climate, let alone the impacts on the horizon.
Driving the news: Last week, two 1,000-year-long rainstorms hit communities about 400 miles apart: St. Louis, Missouri and Hazard, Kentucky.
- In St. Louis, rainfall rates overwhelmed drainage systems and caused rivers and streams to overflow, washing away roads and requiring whitewater rescues.
- In Kentucky, water moved with such force that it pulverized school buses, swept away mobile homes and destroyed roads and bridges.
- Torrential downpours in eastern Kentucky have killed at least 37 people. Even now, homes remain cut off from the outside world, without electricity and surrounded by fast-moving water.
In the Pacific Northwest, last week brought a record heat wave that was not as severe as the 2021 extreme heat event, but lasted longer.
- Seattle set a record for its longest streak of days with highs of 90°F or higher. In Portland, there was a record seven straight days with highs of 95°F or higher in a city where the average high temperature in late July is in the low 80s.
- At least seven deaths have been blamed on the heat in the North West, but the toll in an area where few people have air conditioning could be much higher due to the length of the heat episode and the difficulty to determine heat-related deaths.
- The widespread lack of air conditioning has prompted cities to get creative with cooling shelters, as Portland-area malls and county libraries have been kept open late, for example.
And in California, the week also brought about a forest fire that stunned scientists due to its growth rate and extreme behavior.
- The McKinney Fire took just 48 hours to grow from its initial ignition in Siskiyou County, California to more than 50,000 acres, making it the state’s largest blaze so far This year.
- The fire threw ash into the stratosphere and formed its own thunderstorms due to the intense heat it generated.
- The heat wave, long-lasting drought and transient weather conditions all played a role in this extreme fire behavior. At least two people have died in the blaze so far, while at least 2,000 have been forced to evacuate their homes.
The big picture: We have long designed our infrastructure as if the climatic conditions and extremes of the past, such as the definition of a 100-year, 500-year, or even 1,000-year flood at a particular location, will continue into the future.
- With climate change, this is no longer the case, because the trend of outliers is closer to the norm.
- “Years of wear and tear from weather events have rendered our built environment unable to withstand greater rainfall per event, more intense wind impacts, prolonged temperature extremes, or more unusual wildfire behavior” said Steven Bowen, head of catastrophe analytics at Aon. , by email.
- Population growth also contributes to our precariousness, he said.
The United States, like other parts of the globe, has recently seen an acceleration in the pace and intensity of extreme weather events. When it rains, it rains harder. When it’s hot, it gets hotter and stays that way longer than before.
- Climate science is unambiguous when it comes to heat waves, finding that when the climate warms in response to human burning of fossil fuels for energy, these events are more likely to occur and more intense.
- And when there are wildfires, they behave like veteran firefighters have never seen before.
- “One thing is clear: the modeled climate impacts that we assumed to be 25 to 50 years away are already happening in some cases today,” Bowen said. “The cost-benefit ratio of investing now to save real money tomorrow should be an important determining factor in how we assess risk and limit potential physical damage and loss of life.”
- To some extent, the federal government recognizes this, with funds under the bipartisan Infrastructure Act aimed at strengthening infrastructure and building new projects with climate change in mind.
Yes, but: There’s a chance that even now we underestimate what Mother Nature is capable of due to man-made climate change.
- Some climate scientists and activists raise the possibility that climate change is already leading to missing surprises in their models, like the once-unthinkable temperature overshoot of 104°F (40°C) in the UK, for example.
- If that’s the case, we’d all better buckle up, because more unpleasant surprises are sure to await us.