Climate change could make tracking the rotation of the Earth a lot more challenging and complex for NASA.
For the first time, NASA has been able to pinpoint what is causing changes to the Earth’s rotation and how it moves through space, and climate change is one of the big factors.
“Knowing what the axis of the Earth [is,] is kind of essential nowadays,” Gerald Bawden, a program scientist at NASA headquarters, told the Washington Examiner. “When you use your iPhone, Android, whatever device you use to help with your navigation, knowing where you are accurately on the Earth gets you there faster and safer.”
Yet, climate change, combined with other factors, is affecting the “position and what we define as the center of the Earth … and even the time of day,” he said.
“If I push it really down, it’ll ultimately affect how pizza is delivered,” Bawden quipped.
For now, there aren’t expected to be any day-to-day effects from the changing of the Earth’s rotation, he said. But NASA is looking for the long-term effects of what will become an ongoing change in how the Earth moves through space.
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Bawden leads a number of programs from NASA headquarters that cover the Earth and its many natural processes using satellites. He is responsible for research and analysis on the science of natural hazards and also serves as the principal liaison between the U.S. Geological Survey and NASA on Earth and hydrology issues.
NASA’s Earth Science mission has faced criticism by Republicans as being outside the space agency’s core mission of space exploration. The mission’s programs have suffered budget ups and downs over the last two years, although some get a boost in Trump’s fiscal 2019 budget request.
Improving the agency’s ability to detect “wobbles” in the Earth’s rotation is well within NASA’s overall mission, Bawden said, because these wobbles have bearing on satellite-based global positioning systems, which governments around the world have grown dependent upon in recent decades.
Last fall, NASA scientists identified for the first time that climate change was one of three reasons the Earth has shifted on its axis. The specific cause was the loss of ice in Greenland and other Arctic ice loss due to warming.
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“It’s kind of like an ice skater spinning around, and she lets her hands out a little further, it changes the rotation of the Earth and the wobble ever so slightly,” Bawden explained.
NASA satellite data and modeling showed the Earth drifted 11 yards over the last century.
Glacial rebound, or the return of mountain ranges as glaciers recede, is another reason for the drift. The third reason was mantle convection, or how the heat from the Earth’s core affects its mantle.
The effects of climate change could go beyond the report’s initial findings. Bawden said it’s not just the loss of sea ice that can affect the wobble, but severe weather such as hurricanes. Climate change is not defined by weather events, but the increasing severity and erratic nature of storms in recent years have been tied to steadily rising global temperatures.
Hurricanes, flooding, and drought all affect the rotation of the Earth, Bawden said. Floods, for instance, affect the Earth by redistributing mass in the form of water from one area to another. Drought affects the rotation of the Earth because it represents a loss in mass. It’s like the skater moving her hand closer to her torso, he explained.
“So, instead of being able to spin the same way yesterday, we are spinning a little bit differently because of these big storms,” Bawden added.
