Climate Geoengineering Effort may not work after all

[NickB79]

http://www.accuweather.com/en/weather-blogs/climatechange/climate-geoengineering-effort/20717550

Two German researchers have determined that the climate geoengineering effort to reduce the amount of sunlight reaching the Earth's surface may not stop global warming after all and may have negative effects on the planet's rainfall patterns.

The research team showed how the Earth's water cycle responds differently to heating by sunlight than it does to warming due to a stronger greenhouse effect.

"These different responses to surface heating are easy to explain," says Axel Kleidon of the Max Planck Institute for Biogeochemistry who uses a pot on the kitchen stove as an analogy. "The temperature in the pot is increased by putting on a lid or by turning up the heat - but these two cases differ by how much energy flows through the pot," he says. A stronger greenhouse effect puts a thicker ‘lid' over the Earth's surface but, if there is no additional sunlight (if we don't turn up the heat on the stove), extra evaporation takes place solely due to the increase in temperature. Turning up the heat by increasing solar radiation, on the other hand, enhances the energy flow through the Earth's surface because of the need to balance the greater energy input with stronger cooling fluxes from the surface. As a result, there is more evaporation and a stronger effect on the water cycle.

When Kleidon and Maik Renner applied their results this particular geoengineering scenario, they found out that simultaneous changes in the water cycle and the atmosphere cannot be compensated for at the same time. Therefore, reflecting sunlight by geoengineering is unlikely to restore the planet's original climate.

Shocked, I tell ya, I'm shocked

[Bragi]

1. The headline is misleading

The headline suggests that no forms of geoengineering of any sort would work, but the article suggests that only one type of geoengineering was being studied by these researchers. Yes?

[NickB79]

2. Yes, they were only addressing one form of geoengineering

But the form they addressed (finding ways to block incoming radiation, usually suggested as done with sulfur dioxide injections) is considered one of the easiest, most cost-effective potential ways to do geoengineering.

If this particular route doesn't work, the cost of geoengineering (and hence the likelihood they will be successful) becomes more and more prohibitive.

[caraher]

3. But... but...

As a friend of mine likes to joke about many proposed fixes to problems...

(P1) We must do something!

(P2) This is something...
------------------------------
(C) Therefore, we must do this!

I'm more concerned about unintended consequences, but uncertain effects are more great reasons not to expect magical technology fixes to arrest climate change!