Space Traffic May Be Creating More Clouds 57
seagirlreed writes "Rocket traffic may be adding water to the Earth's mesosphere, leading to more very high clouds in this layer of thin air on the edge of space. From the article: 'A team of researchers looking for an expected decrease in the number of clouds in this layer, as solar activity and heating have ramped up, were instead surprised to find an increase in the number and brightness of clouds in this near-outer-space region over the last two years. ... The source of the water to make the clouds is a puzzle, Siskind explained, because there is not much sign of it coming up into the mesosphere. On the other hand, rockets and, until recently, shuttles roaming in space could rain water exhaust down into the mesosphere.'"
Re:another variable in climate modelling (Score:2, Informative)
Since CO2 levels have recently pass the 400 ppm level [guardian.co.uk] for the first time in "recorded history" (ignoring for the moment that nobody recorded this until last 50 years or so),:
You forget the well-known practice of extracting the air from bubbles in ice cores, for direct measures.
Re:Cloud size (Score:4, Informative)
Re:FUD (Score:4, Informative)
Funny thing about clouds... they increase reflectivity. As the temperatures go up more water vapour goes up into the sky to form clouds, which reflect incoming light and heat and provide a cooling effect. i.e.: it's self-regulating.
This is Richard Linzen's "Iris" hypothesis. One of the few plausible bits of actual science from the so-called climate skeptics. Unfortunately, it seems not to work and was thoroughly refuted [skepticalscience.com] about ten years ago.
Re:another variable in climate modelling (Score:2, Informative)
Always good to include a citation...
Keeling: The reconstructions before the ice core period, which take us only back 800,000 years, are a lot less secure. In the case of ice cores, we actually have samples of old air. And subject to some small caveats, you can simply analyze those and figure it out. In earlier geologic eras, the reconstruction of carbon dioxide depends on more indirect measurements. The work of people like Mark Pagani at Yale, who is in the business of reconstructing paleo CO2, shows that the last time that CO2 was around this level was probably in the mid-Pliocene, 2 to 4 million years ago.
http://www.guardian.co.uk/environment/2013/may/14/record-400ppm-co2-carbon-emissions
Re:Great, kill 2 birds (Score:4, Informative)
water != cloud
white cloud reflects a lot of sun's radiation back into space. Yes water vapor is a strong greenhouse gas, but we're talking about more efficient trapping of [heat that has been greatly reduced by higher albedo before it ever hit the ground]. Net effect is reduced overall heat.
Just go out on a cloudy summer day vs. a cloudless one and feel the effect.