Thanks, Climate Change: Heat Waves Will Keep on Grounding Planes

Last month, Phoenix enduring a blistering heat wave, with temperatures so high that airport officials had to cancel dozens of flights. The reason was two-fold. First off, some jet engines risk catching on fire in extreme heat. And when air gets hot, it expands and becomes less dense—so an airplane’s wings can’t generate enough lift to get off the ground. Planes either need to speed up during take-off or use a longer runway.

But Phoenix’s flight delays aren’t a one-off event. As the Earth’s climate undergoes a 1 to 3 degree Celsius warming over the next half-century, extreme heat waves will hit more frequently. Some of these heat waves will hit airports with short runways. Forget about rain delays or missing flight crews. At places like Washington’s Reagan National Airport, New York’s LaGuardia Airport, and Dubai International, the real trouble will come during heat waves.

During the hottest part of the day, 10 to 30 percent of planes will have to offload cargo or people, according to a new study by graduate student Ethan Coffell and climate scientist Radley Horton at Columbia University. “This study shined a light on a potential vulnerability,” Horton says. “A lot of airplanes at full capacity are ill-equipped to take off on some of the world’s runways when temperatures get really high.”

The scientists looked at five common commercial airplane models—the Boeing 737-800, Airbus A320, Boeing 787-8, Boeing 777-300, and Airbus A380—and calculated how their takeoffs would be affected at 19 airports around the world, based on projected temperatures from 27 different global climate models. The runways represented the most common climates, elevations, and runway conditions at busy airports around the world—including US airports in Denver, Phoenix, Chicago, Atlanta, New York, Washington, DC, Los Angeles, Houston and Miami.

The good news for air travelers is that London, Paris, and JFK in New York will be able to shrug off the worst of future heat waves. But a Boeing 777-300 departing from Dubai at the time of the daily highest temperature may be weight-restricted about 55 percent of the time according to the study, which appears today in the journal Climactic Science. Because of the short runways, airplanes at Washington’s Reagan-National (7,170 feet) and New York’s LaGuardia (7,000 feet) will also have to lighten their load to get off the ground. Expanding the runways probably won’t work, given that they are either sandwiched along the Potomac River or Jamaica Bay.

Heat waves aren’t the only problem facing the aviation industry as the Earth’s climate changes rapidly. Other scientists have calculated that severe turbulence—the kind that sends drink carts flying and sometimes even unbuckled passengers—will increase over certain transatlantic routes that follow the meandering jet streams.

Paul D. Williams, an atmospheric scientist at the University of Reading who published on the connection between climate change and turbulence this past year, thinks the industry needs to start dealing with climate change more aggressively. They could develop engines that produce fewer greenhouse gases, for one, as well as adapt its planes to the future world. “I’ve yet to see a benefit of climate change to aviation,” Williams says. “All the published studies have been about thing getting worse.”

There are plenty of solutions out there, some more complicated than others. Flights may have to leave earlier in the day when its cooler, Horton suggests, or aircraft manufacturers may have to make planes lighter. Or engineers could step in, building some kind of special new wings that generate additional lift. There’s one other option that probably won’t happen: leaving three or four paying customers back at the terminal in order to make the takeoff weight.

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NASA finally admits it doesn’t have the funding to land humans on Mars

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NASA’s chief of human spaceflight, Bill Gerstenmaier, speaks at the Humans to Mars summit in 2015.

NASA


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For the last five years or so, NASA has sold the public on a Journey to Mars, a grand voyage by which the agency will land humans on the red planet during the 2030s. With just budgetary increases for inflation, the agency said, it had the resources for humanity’s next great step, to land crews safely on Mars, and to bring them home. The agency’s new rocket, the Space Launch System, and spacecraft, Orion, were sold by NASA administrator Charles Bolden as the vehicles that would get the job done.

There were plenty of naysayers. For example, a National Research Council report cautioned that the agency had too much work, and too little funds, to accomplish these goals in the 2030s with the SLS rocket—and that sustaining a “Mars program” into the 2040s would be a tremendous challenge. NASA’s remarkable response to this critical report was that it validated the Journey to Mars.

Can’t land

Now, finally, the agency appears to have bended toward reality. During a propulsion meeting of the American Institute for Aeronautics and Astronautics on Wednesday, NASA’s chief of human spaceflight acknowledged that the agency doesn’t really have the funding it needs to reach Mars with the SLS rocket and Orion spacecraft. These vehicles have cost too much to build, and too much to fly, and therefore NASA hasn’t been able to begin designing vehicles to land on Mars or ascend from the surface.

“I can’t put a date on humans on Mars, and the reason really is the other piece is, at the budget levels we described, this roughly 2 percent increase, we don’t have the surface systems available for Mars,” said NASA’s William H. Gerstenmaier, responding to a question about when NASA will send humans to the surface of Mars. “And that entry, descent and landing is a huge challenge for us for Mars.”

This seems like a fairly common sense statement, but it’s something that NASA officials have largely glossed over—at least in public—during the agency’s promotion of a Journey to Mars. Agency officials have also been loathe to mention the possibility of NASA astronauts landing on the Moon, because George W. Bush had an initiative to return to the Moon that President Obama canceled. However, Gerstenmaier opened the door to this possibility Wednesday.

Maybe the Moon?

“If we find out there’s water on the Moon, and we want to do more extensive operations on the Moon to go explore that, we have the ability with Deep Space Gateway to support an extensive Moon surface program,” he said. “If we want to stay focused more toward Mars we can keep that.”

It has been a long time since NASA, especially its chief human spaceflight official, talked openly about an “extensive Moon surface program.” However after six months of a new presidential administration, the agency realizes that its destination may well change. Therefore its leadership is keeping the decision about destinations open, be it the surface of the Moon or Mars.

The reality is that NASA may not be able to go either place unless something changes. The agency doesn’t have the funding to build a large lunar outpost if it must rely on the Space Launch System—which will only fly about once a year, at a cost of more than $1 billion. Mars landings, clearly, would cost even more with the big, expendable rocket approach requiring five or more launches per mission.

Another, less costly option is having the freedom to rely much more heavily on partly or completely reusable launch and in-space transports systems being built by SpaceX, Blue Origin, and United Launch Alliance. Politically, so far any reliance on commercial companies for deep space exploration has been a non-starter in Congress. But that could change, as Vice President Mike Pence has been making some noise about increasing commercial partnerships at NASA. “The truth is that American business is on the cutting edge of space technology,” he recently said.

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