Published on November 15th, 2018 | by Steve Hanley0
Ho, Hum. A Warmer Planet Means Hurricanes Will Drop More Rain & Have Higher Winds
November 15th, 2018 by Steve Hanley
Katrina, Harvey, Irma, Maria — how much did warmer global average temperatures affect those recent storms? That’s the question Christina Patricola of Lawrence Berkeley National Laboratory wanted to answer. Together with fellow researcher Michael Wehner, she modeled 12 recent hurricanes, including Katrina. Then she and Wehner varied ocean temperatures and atmospheric conditions in their computer models and noted how the changes affected those storms.
The results of the study have just been published in the journal Nature with the title “Anthropogenic Influences On Major Tropical Cyclone Events.” The purpose of the study was to compare how the storms behaved today versus how they would have behaved in the pre-industrial era when average global temperatures were lower. That analysis will help inform the scientific, political, and business communities about how warmer temperatures will affect future storms.
“Climate change has exacerbated rainfall and is set to enhance the wind speed,” Patricola tells The Guardian. “My hope is that this information can be used to improve our resilience to the kinds of extreme weather events we are going to have in the future.” Patricola and Wehner tweaked the conditions to watch what would happen if Katrina, Irma, and Maria had unfolded in a pre-industrial world, and found that global warming boosted the deluge by between 4 and 9%. The team also analyzed wind speeds, but didn’t see much of a contribution of global warming for the recent storms.
That could change in the future. The study found that if average global temperatures rise 2º to 3º C by 2100 — as they surely will if humanity continues to dump millions of tons of carbon dioxide into the atmosphere every year — future hurricanes could drop up to 30% more rain and have winds as much as 33 miles per hour stronger than current storms.
James Elsner, an atmospheric scientist at Florida State university, tells The Guardian that Patricola’s study is supported by previous findings showing warming global temperatures have an impact on hurricanes. “There’s still discussion over the size of the affect but it’s clear. We need to connect the dots after storms more than we have in the past. We know climate change is having an affect, the only real question is how much.”
Ho, Hum At 1600 Pennsylvania Avenue
One place we know will not be connecting the dots is the White House. Putative president Donald Trump last year reversed regulations created by the Obama administration that would have required all new federal projects to plan for greater flooding in the future. Trump wants to avoid wasting federal tax dollars on things that cannot happen because global warming is, after all, just a hoax created by the Chinese to wreck the US economy. Nothing to see here. Move along. Studied ignorance has risen to a high art under the auspices of The Donald.
Costlier Storms Getting The Attention Of Insurers
America’s political leaders may shrug off the effects of a warmer planet on hurricane activity but the insurance industry is certainly paying attention. Last year’s trio of super storms in the US — Harvey, Irma, and Maria — cost insurers more than $300 billion. Politicians may not care much about climate change — it’s not as sexy as racism, homophobia, misogyny, and xenophobia — but when insurers start jacking up rates for new construction in flood zones the immutable laws of economics will kick in hard. Of course, by then it will be too late and the blame game will begin.
Cities May Invite More Flooding
A second study published in Nature this week is entitled “Urbanization Exacerbated The Rainfall And Flooding Caused By Hurricane Harvey In Houston.” It examines the effect urban areas have on mega-storms. This is a new area of inquiry for climate scientists but it may offer important insights for city planners and architects going forward. Gabriele Villarini is an hydrologist at the University of Iowa. Together with colleagues at Princeton, he took a closer look at Hurricane Harvey, the monster storm that dumped 5 feet of rain on Houston in 2017.
It is well understood that impermeable materials like concrete and asphalt exacerbate flooding because water has nowhere to go and can’t be absorbed by the surrounding land. But Vallarini wanted to know what Harvey would have been like if the city of Houston did not exist.
Apparently, the skyline of the city slowed the passage of the storm, allowing more rain to fall in the area than would have fallen if the land below were just farms. “The skyline, the tall buildings, the city footprint — we don’t know which one is more important,” Villarini tells The Verge. More research will be needed to determine if the findings pertain just to Houston and just to Harvey or whether they apply to other metropolitan areas and other hurricanes.
“This is, as far as I know, a new result and, as the authors point out, has important implications for urban planning,” says Kerry Emanuel, a professor of atmospheric science at MIT who was not involved in the study.
What Can Be Done?
In a perfect world, these studies would be a focus of discussion among government leaders. But the odds are they will have no impact on the US Congress or the federal government whatsoever. Someday, people will look back and ask why, with so much information available, no positive steps were taken by leaders of the United States to address a warming world. What possible explanation will they offer?
“Gee, we’re sorry. We believed all climate scientists were frauds whose research was fabricated to get more federal grant money?” Good luck with that when you find yourselves facing charges for perpetrating crimes against humanity. If history teaches us anything, it is that economics will impel the actions needed to address a warming planet, not the political process. in which profiles in cowardice are the order of the day, every day.