Scientists say climate change worsened the impact of Harvey, which brought historic rainfall and devastation to Texas

Hurricane Harvey set new records for rainfall and economic destruction. After making landfall on August 25, Harvey dropped more than 50 inches of rain and earned the distinction of being the most extreme rain event in U.S. history. Estimates of Harvey’s costs range from $81 billion to up to $190 billion, the uppermost of which would make it the nation’s costliest natural disaster. [Houston Chronicle, 9/4/17; The Washington Post, 8/29/17; Los Angeles Times, 9/1/17; Newsweek, 9/1/17]

Scientists say climate change worsened Harvey’s impacts. A number of climate scientists have stated that climate change exacerbated the worst impacts of Hurricane Harvey, as warm ocean water fueled the storm’s intensity. Climate scientists have also said that climate change may have been responsible for Harvey stalling over Texas, which was a major factor in its record rainfall. Texas Monthly reported:

In a mere 48 hours, Harvey went from a middling tropical storm, with winds of 45 miles per hour, to a Category 4 hurricane, with winds of 130 miles per hour. When it hit land, it dumped close to 50 inches of rain on Texas, which makes it the biggest rain storm in U.S. history. “There are many explanations for Harvey’s rampage,” Dr. Andrew Dessler, a professor of atmospheric science at Texas A&M in College Station, said. “But human induced climate change definitely made the storm worse.”

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Few bodies of water have heated up like the Gulf of Mexico. As a result, when a tropical storm passes over the Gulf, those warm waters become pure fuel for that storm to tap. What’s more, because the temperatures in the atmosphere over the Gulf are also warmer, more ocean water is evaporating and hanging in the air, just waiting to be swept up by a storm and dumped over land as rain.

We’re not saying that climate change is creating more tropical storms or hurricanes,” said Dr. Daniel Cohan, an atmospheric scientist and professor of environmental engineering at Rice University in Houston. “But what’s becoming clear is that once these storms form, they are likely to become much more intense.” Cohan noted that in the past three years, Houston has been hit by three so-called “500-year storms.” “The chances of that happening by coincidence are just about zero,” he concluded.

Cohan even speculated that global warming was the reason Harvey stalled over southeast Texas. “We know that with climate change, as the world gets warmer, the jet streams are now moving away from tropics and moving closer to the poles,” he explained. “What happened in Harvey’s case is that the jet stream wasn’t out there to push the storm along. It had moved north. I think for that very reason we’ll see more of these hurricanes stall over land, which means more devastating monster rains.” [Texas Monthly, 9/5/17; The Guardian, 8/28/17; The Atlantic, 8/27/17]

Broadcast networks: ABC and NBC did not air a single segment on the link between climate change and hurricanes like Harvey, while CBS and PBS each aired three

Neither ABC nor NBC mentioned that climate change influences hurricanes like Harvey. From August 23 to September 7, none of the morning, nightly, or Sunday news shows on ABC or NBC featured a segment that discussed the link between climate change and hurricanes.

CBS aired three segments discussing the connection between climate change and hurricanes. The August 26 episode of CBS This Morning featured an interview in which physicist Michio Kaku discussed how warm ocean waters fuel hurricanes like Harvey. The August 30 episode of CBS Evening News and the August 31 episode of CBS Morning News both featured a segment in which environmental engineering professor Jim Blackburn explained that Harvey was a “climate-influenced storm” and said, “This is what the climate scientists have been telling us would happen.” [CBS This Morning, 8/26/17; CBS Evening News, 8/30/17; CBS This Morning, 8/31/17]

PBS also aired three segments that highlighted the link between climate change and hurricanes. On the August 30 episode of PBS NewsHour, correspondent Miles O’Brien interviewed climate scientists and experts about the connection between climate change and extreme weather events. O’Brien again brought up climate change in the context of Hurricane Harvey on September 1 during a discussion with Mark Shields and David Brooks about whether Harvey would bring about a sea change in political discussions about climate change. And, on the August 31 episode of PBS NewsHour, O’Brien referred viewers to the show’s website to watch an interview he conducted with Rep. Clay Higgins (R-LA), stating, “The record-breaking nature of Harvey has renewed the conversation about the link between climate change and extreme weather events. Congressman Higgins is a vocal climate change skeptic. I asked him if the events of the last week have at all changed his mind. You can listen to that exchange on our Web site, PBS.org/NewsHour.” [PBS NewsHour, 8/30/17, 9/1/17, 8/31/17, 8/31/17]

Prime-time cable: Fox dismissed climate change's impact on Harvey, while MSNBC and CNN discussed the connection

In most of Fox’s segments that discussed climate change and Harvey, hosts argued that people shouldn't draw connections between the two. From August 23 to September 7, Fox News aired six prime-time segments on the hurricane that mentioned climate change. Three segments on The Five and one segment on Tucker Carlson Tonight featured Fox hosts dismissing or criticizing speakers who pointed out global warming's effect on the storm.

The September 1 edition of Special Report with Bret Baier did feature media figures and academics discussing how climate change worsened Harvey, but it also featured a clip of climate denier Myron Ebell saying, “The global warming alarmists are really doing a disservice in the public debate by saying we should be spending trillions of dollars to try and reduce greenhouse gas emissions when in fact we should be spending billions of dollars to upgrade the infrastructure in the Gulf Coast of Florida.”

The August 28 episode of The Fox News Specialists featured the only segment in which the link between Harvey and climate change was discussed and not rebutted, when radio host Jamila Bey stated, “These things happen. Climate change is real. We need to make sure that our policies absolutely recognize this and say how do we make sure that other areas that are prone to flooding get the resources that they need.” The hosts did not contradict Bey’s statement, instead moving on to another segment. [Fox: The Five, 8/25/17, 8/30/17, 8/30/17; Tucker Carlson Tonight, 8/31/17; Special Report with Bret Baier, 9/1/17; Fox News Specialists, 8/28/17]

CNN aired five segments discussing the link between climate change and Harvey. During the time period Media Matters analyzed, CNN ran five prime-time segments that discussed a link between climate change and Hurricane Harvey. For example, on the August 30 and August 31 episodes of Cuomo Prime Time, host Chris Cuomo asked counselor to the president Kellyanne Conway and Sen. Bernie Sanders (I-VT) whether the Trump administration would begin to have a discussion about how climate change impacts storms like Harvey. In both instances, Cuomo noted that the number of so-called “100-year storms” has increased significantly. [CNN: Cuomo Prime Time, 8/30/17, 8/31/17; Erin Burnett OutFront, 8/31/17; CNN Tonight, 8/29/17; The Situation Room, 8/28/17]

MSNBC also aired five segments that highlighted the connection between climate change and the hurricane. MSNBC aired five prime-time segments about the link between climate change and Harvey on its prime-time shows, including on the August 28 edition of All In with Chris Hayes, in which Hayes interviewed reporter Neena Satija. Sajita co-wrote a 2016 ProPublica report on Houston that cited multiple scientists issuing warnings about catastrophic flooding. Satija told Hayes, “Local officials in Houston didn’t have plans to study the effects of climate change in the city or think about whether the city needs to plan for more frequent and more intense rainstorms, which scientists say are a sure thing for Houston.” [ProPublica, 12/7/16; MSNBC: All In with Chris Hayes, 8/28/17, 8/29/17; The Last Word with Lawrence O’Donnell, 8/30/17, 8/31/17; Hardball with Chris Matthews, 8/29/17]

Chart by Sarah Wasko

Methodology

Media Matters ran the search term “Harvey AND (climate OR warming OR emission! OR carbon OR CO2 OR greenhouse gas!)” in Nexis to identify segments between August 23 and September 7 that mentioned both the hurricane and climate change.

On the broadcast networks, we examined the morning, evening, and Sunday news shows on ABC, CBS, and NBC, as well as PBS NewsHour, the only PBS program archived in Nexis. For CNN, MSNBC, and Fox News, we examined the networks’ prime-time shows that air on weekdays from 5 p.m. to 11 p.m.