Destabilized Saturday Edition #30
The climate model detail that explains widespread flooding, Bordeaux burning, finding love in the aftermath of hate, no previous sheepdog experience
Quick note #1: It’s HUGE the Senate and House have passed the Biden climate bill, now called the Inflation Reduction Act (which also includes good and important health care policy changes). While it’s true it’s not “enough” – that would be completely eliminating net greenhouse gas emissions yesterday – it is a giant, historic step forward in slowing and eventually stopping climate change.
Quick note #2: Without making any judgment about the FBI’s authorized removal of government documents from Trump’s home, Republicans’ predictably unhinged, violence-infused response to the was alarming. These two pieces give a good overview.
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One defining feature of contemporary life is there’s always so much happening that important events never get the attention and focus they deserve and would have gotten a generation ago. One recent trend that has received too little attention is the unprecedented flooding around the globe. Since late July there have been more than a dozen highly destructive flooding events (source: Twitter + Floodlist):
Niger, 27 dead, 6,000 homes destroyed
Sudan, 6 dead, 2,500 homes destroyed
South Korea, 9 dead, 6 missing, 49.6 cm (19.5 in.) of rain in 48 hours
Death Valley USA, 100s stranded, 75 percent of a year’s worth of rain in 3 hours
Yemen, 38 dead, scores of homes damaged, 35 cm (14 in.) of rain in 24 hours
Japan, 2 bridges destroyed, 540,000 ordered to evacuate, 16.3 in. rain in 24 hours
Sri Lanka, 3 dead, 3 missing, 300 homes damaged, 9.5 in. rain in 24 hours
Uganda, at least 24 dead, more missing, scores left homeless
Kentucky USA, at least 37 dead, another 37 missing
Iran, at least 53 dead, 16 missing, hundreds of villages damaged
St. Louis USA, 1 dead, extensive property damage, 9 in. of rain shatters record
Central African Republic, 13 dead or missing, thousands of homes damaged
Russia, at least 2 dead, 4 missing, hundreds of buildings damaged
Denver USA, 1.76 in. of rain in 26 minutes, I-70 closed
I left off this list destructive but slightly less devastating floods in Venezuela, Senegal, Colombia, Mexico, The Gambia, Thailand, Nigeria, Nevada, and southern Illinois. A bit earlier in July there was serious flooding in China and Afghanistan, where 39 people died. And I’m sure I missed some, too. This list is both long and strikingly global. The locations of these floods are scattered across the continents.
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One thing I’d like is better metric conventions for measuring the overall historic-ness of this set of rainfall events. I haven’t seen a good answer to the question, “how unusually heavy were the rains that caused these floods?” I think much of the data required to formulate an answer exists, even if its imperfect. What we need are better availability, smarter ways to frame and slice it, and updated journalistic conventions for conveying what’s happening.
For instance, I would love to know how many places on earth in the last X days have experienced rainfall over a period of Y hours that exceeded the previous record by Z percent or more? X and Y here could vary (e.g., 7 days 30 days, 90 days; 1 hour, 6 hours, 24 hours, 72 hours; 5%, 10%, 20%) to produce a set of metrics that measure the aggregate intensity level of global rainfall over different periods of time. Climate change is moving so fast that our analytical and reporting conventions haven’t kept up with our need to understand the transforming natural world.
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The other question we’re left with is why rainstorms of such extreme intensity are already happening consistently when climate models weren’t predicting them for decades. This recent piece from Grist about Yale physicist Joshua Studholme asks this very question and offers a fascinating answer:
Climate scientists have long known that global warming increases rainfall, since a hotter atmosphere holds more water vapor. But when the remnants of Hurricane Ida swept into the Northeast in the summer of 2021, they brought the kind of catastrophic rain event experts had predicted would typically occur later this century. Studholme’s study sought to investigate why Ida, and the many other record-breaking rain events that occurred last year across the globe in Europe, China, and other places, seemed to happen ahead of schedule.
Studholme zeroed in on a seemingly small detail in climate models. He looked only at models that included a calculation predicting an increase in precipitation efficiency, which is the proportion of rain that falls all the way to the earth’s surface rather than evaporating back into the atmosphere on the way down.
By focusing on the group of climate models that most realistically simulate the actual physics of raindrops, Studholme’s study found that the average climate model likely underestimates how extreme precipitation will change in response to global warming. It’s possible that there will be a twofold increase in the volume of extreme rainfall in the 21st century compared to what previous studies estimate, he said, which would help explain why the globe is already seeing such intense and unprecedented rainstorms.
In other words, the models whose algorithms varied precipitation efficiency with temperature accurately predicted the timing of the extreme rain events we’re seeing. Those that omitted the connection between temperature and precipitation efficiency significantly underestimated how soon intense rainfall would become commonplace.
Two points here. First, this gives me a much more intuitive sense of how massively intricate climate models are. Think about all the natural system dynamics in the biosphere that are as granular as what fraction of raindrops reach the ground versus getting reabsorbed into the atmosphere. Then imagine trying to program a large set of interlocking algorithms that include calculations describing each detail. And then imagine proof-reading it to make sure it doesn’t contain any little errors that would cause you to misdescribe the future of human life on earth. It’s a lot.
Second, this likely does explain in large part why rainfall has already become so much more intense. Not only do higher temperatures 1. cause more surface water to evaporate into the atmosphere and 2. enable clouds to hold more moisture that eventually gets released as rain, but 3. increased heat also reduces the portion of raindrops that are absorbed on the way down so that more fall on land. They’re now falling in such quantities that the systems humans have built can’t handle the volume, which produces powerful, deadly floods.
In order to live safely on earth over the next century, we have to rebuild our systems to higher tolerances. Upgraded infrastructure has to be able to withstand the weather events that our transformed biosphere will whip-up even more powerfully and frequently in the future.
My Work
Climate change will dramatically worsen inequality
Place will not be the only driver of unequal climate harms. The more time I spend reading and thinking about climate change the clearer it is that money, along with location, will be the critical dividing line. Most people and communities with enough money will be able to protect themselves from the worse climate impacts, while impoverished people and communities around the globe will be more exposed and have a more difficult time finding shelter from literal and figurative storms.
Related:
Interesting Reads
How Covid Stole Our Time and How We Can Get It Back
[T]he life we’ll be living 10 years from now will largely be determined not by our past selves but by our present and future selves. If we imagine what we might regret down the road, it’s very much in our hands to do something about it now.
This is the good news about being a human. The time we have left with family and friends is not a law of nature like the weeks we have left to live. It’s a function of priorities and decisions.
Tweets of the Week
Extreme Weather Watch
Photo of a flood that didn’t even make the list, in Washington, DC this week:
Creeping Authoritarianism Watch
Progress Joy and Hope
This is my kind of Unite the Right 5-year anniversary retrospective:
