New Research Strengthens The Theory That Climate Change Will Make Our Space Debris Problem Worse

Conceptual image of space debris around Earth, not to scale.

In the near future, two big, catastrophic problems will become one: Climate change is likely to worsen the problem of space debris. a study It was published last month in Geophysical Research Letters.

Changes in air density can result in an over-densification of the upper atmosphere, making satellites more likely to collide. Moreover, recent research projects that the upper atmosphere will lose density twice as fast as in the past under middle-of-the-road climate scenarios.

“Space debris is becoming a rapidly growing problem for satellite operators due to the risk of collisions,” said Ingrid Knossen, an atmospheric scientist at the UK’s Natural Environment Research Council and lead researcher on the study. press release From the British Antarctic Survey. “There is a long-term decrease in the density of the upper atmosphere [the issue] worse,” he added.

NASA tracks the estimated number of objects in orbit around Earth. This chart, based on 2019 data, shows all objects currently being tracked in Low Earth Orbit.

It’s counterintuitive, but as humans continue to pump greenhouse gases into the lower atmosphere, thereby warming the surface of our planet, we middle and upper atmospheric cooler. The reasons are varied, but a major contributing factor is CO2 emissions.

Carbon dioxide molecules absorb heat easily. In the lower atmosphere, this means more molecules are bumping into each other and more heat is reflected back to Earth. But in the upper atmosphere, where there are fewer molecules around, the heat-trapping CO2 stores energy so tightly that it’s more likely to escape into space than meet another particle and heat the thin air.

As the upper atmosphere cools, it loses its density. Less dense air means less drag on Earth-orbiting satellites and other space objects. Our atmosphere must be self-purifying, as objects fall from orbit and burn up. However, in a less dense environment, satellites and space debris remain airborne for longer periods of time.

Atmospheric space debris collection in itself growing, impending crisis. We rely on satellite infrastructure for communications, research and data collection, and weather forecasting, and we’re running out of real estate fast. There are already some concerns collisions and near corn.

Nowadays, there are more 30,000 trackable items According to the European Space Agency, it orbits in low Earth orbit. NASA estimates that 23,000 units Debris larger than a softball and about 100 million smaller fragments orbit the Earth. And each collision creates more pieces of debris. Add in climate change and accidents may increase.

Previous research reached similar conclusions. A 2021 editionThe paper, also contributed by Gnossen, found that objects in low Earth orbit would have 30% longer lifetimes under 1.5 degrees Celsius of global warming compared to the year 2000.

The latest findings reinforce these past results and offer a new quantification of atmospheric change. According to the study, the upper atmosphere will lose heat and density twice as fast in the next 50 years than in the last half century. This acceleration closely follows the expected concurrent increase in atmospheric CO2 levels between now and the 2070s, the study author writes.

Cnossen cited computer models to reach this conclusion. He used climate, emissions and atmospheric data to create one of the most complete models of climate change in the upper atmosphere to date.

“The changes we see between the upper atmosphere climate over the past 50 years and our projections for the next 50 years are the result of carbon dioxide emissions,” Cnossen said in a press release. For the satellite industry and policymakers, understanding climate change — beyond Earth’s surface — is “increasingly important,” he said.

In the next work, the scientist hopes to explore a wider range of climate and CO2 emission scenarios to better prepare the world for all possible space debris outcomes.

And ideally, it will lead to a better understanding of the problem meaningful solutions. “I hope this work will help guide appropriate actions to control the problem of space pollution,” Cnossen said in a statement. Ultimately, he wants to “ensure that the upper atmosphere remains a usable resource in the future.”

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