3 ms·

A very short term difference. We would not make much of a dent (or bump, if you are into being literal) in the thermal balance of our planet if our greenhouse g

by usrusr 5y ago

A very short term difference. We would not make much of a dent (or bump, if you are into being literal) in the thermal balance of our planet if our greenhouse gas activities did not involve unearthing large quantities of carbon that had been buried away "forever" in climate timescale. Years are not the issue, the problem is that everything we unearth won't re-bury itself in centuries and millennia.

regularfry 5y ago
The difficulty is in catastrophe curves. While the water from a single flight doesn't hang around long, there are always aircraft in the sky, so it's constantly getting refreshed and amounts to a constant thermal load. If that additional thermal load, on top of the other greenhouse gases, is enough to tip some nonlinear system past its tipping point, then we've still got a problem. Fortunately, it's also its own solution: if we find we need to avert a catastrophe next week, grounding all flights today might do the trick. But of course it's very hard to predict a tipping point to that level of accuracy. If we had that sort of movie-plot threat in climate change we might actually see meaningful action. So yes, while carbon dioxide and methane are terrible, awful, no good gases we shouldn't be dumping into the atmosphere with quite such abandon, choosing to maintain water vapour at a particularly vulnerable point in the system is also something of an unforced error.
- labster 5y ago
  You misspelled “radiative forcing” as “thermal load” but the analysis is correct. We did in fact shut down flights on 9/11 and that’s when we noticed the cooling. The tipping points are like, well, there are millions of them and they all interact with each other, thus computer models. I feel unforced error is bit harsh too. Climate sustainability is a series of mostly hard problems, and aviation is one of the hard ones.

by usrusr 5y ago

regularfry 5y ago

The difficulty is in catastrophe curves. While the water from a single flight doesn't hang around long, there are always aircraft in the sky, so it's constantly getting refreshed and amounts to a constant thermal load. If that additional thermal load, on top of the other greenhouse gases, is enough to tip some nonlinear system past its tipping point, then we've still got a problem. Fortunately, it's also its own solution: if we find we need to avert a catastrophe next week, grounding all flights today might do the trick. But of course it's very hard to predict a tipping point to that level of accuracy. If we had that sort of movie-plot threat in climate change we might actually see meaningful action. So yes, while carbon dioxide and methane are terrible, awful, no good gases we shouldn't be dumping into the atmosphere with quite such abandon, choosing to maintain water vapour at a particularly vulnerable point in the system is also something of an unforced error.

labster 5y ago
You misspelled “radiative forcing” as “thermal load” but the analysis is correct. We did in fact shut down flights on 9/11 and that’s when we noticed the cooling. The tipping points are like, well, there are millions of them and they all interact with each other, thus computer models. I feel unforced error is bit harsh too. Climate sustainability is a series of mostly hard problems, and aviation is one of the hard ones.