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Felaguin t1_iw0wgze wrote

Reply to comment by SuaveMofo in Climate change is extending the lifetime of space debris. A new study found that the density of the thermosphere will decrease by 30-35% at an altitude of 250 miles over the next few decades. That loss of drag would increase the lifetime of space debris in LEO by 30% compared to 2000. by clayt6

I did read the article but the premise is bullshit and flies in the face of decades of observation for anyone who has tracked satellites.

You can see this every solar max cycle. The atmosphere heats up when the Earth heats up. Drag increases on satellites in LEO because the atmosphere expands when it heats up. We have literally decades of data on this.

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SuaveMofo t1_iw0x7ft wrote

There is overwhelming evidence that the climate of the upper atmosphere is changing. While the troposphere shows a global warming trend, the middle and upper atmosphere (stratosphere, mesosphere, and thermosphere) have been cooling (e.g., Cnossen, 2012; Laštovička et al., 2006). This cooling results in thermal contraction, resulting in a lowering of ionospheric layers (Bremer et al., 2012; Rishbeth & Roble, 1992) and a reduction in thermosphere density at fixed height (Emmert, 2015; Keating et al., 2000; Weng et al., 2020). The increase in atmospheric CO2 concentration is thought to be the main driver of the global mean cooling and contraction of the upper atmosphere (e.g., Laštovička et al., 2006), with other trace gases playing a relatively minor role (Qian et al., 2013)

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SuaveMofo t1_iw0wt1t wrote

You didn't read the article because it specifically states that when the lower atmosphere is heated the upper atmosphere experiences the opposite. They have sources, you don't. They are scientists, you clearly are not. Stop running your mouth and let the people who know what they're doing do their work, because you don't have the answers.

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Felaguin t1_iw0xevt wrote

Mmm … no, that’s not how it works and you have no idea what data I have. But here’s a clue — you can actually download the element sets for the last 3 decades and look at the drag experienced at a variety of altitudes. The claim was specifically for 250 miles — 400 km — where we have a LOT of data because we tend to keep a very careful eye on objects at the same altitude as the ISS.

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