Sunday, November 18, 2012

Space Debris and Climate Change (Really?)

I don't understand this notion that climate change will negatively affect space debris:
In a study published in the journal Nature Geoscience, a research team led by John Emmert of the U.S. Naval Research Laboratory's Space Science Division in Washington, described a new method for quantifying increases in carbon dioxide in the hard-to-measure portion of the upper atmosphere known as the thermosphere, which can't be reached by balloons and aircraft.

In that region, more than 50 miles above Earth's surface, carbon emissions cause cooling rather than warming because carbon dioxide molecules collide with oxygen atoms and release heat into space. Because such cooling makes the planet's atmosphere contract, it can reduce drag on satellites and debris that orbit the earth, possibly having "adverse consequences for the orbital debris environment that is already unstable," the researchers wrote.
The orbit of satellites and space debris is already affected by solar storms, which can heat the upper atmosphere and cause it to temporarily expand. Low-orbiting satellites experience more drag, which can shorten their lifetime, but the storms also clear out some low-lying space debris.

Is the rate of change of CO2 in the thermosphere (they find +24 ppm/decade) really enough to cause havoc to satellites on top of this? And space debris is random anyway -- this just mixes it up.... I guess I'm skeptical.

No comments: