…or does warming cause CO2?
Darn that pesky “correlation is not causation” thingie.
[Update a few minutes later]
This seems sort of related — does iron-rich dust cause ice ages?
The thinking goes that, during warm periods, much of the Southern Ocean is an oceanic desert because it lacks the iron crucial for plankton growth. That changes at the start of ice ages, when a wobble in the planet’s orbit causes an initial cooling that dries the continents, generates dust storms – particularly in central Asia – and sends dust onto the surface of the Southern Ocean.
The plankton that then bloom take the carbon they need from the water, causing the oceans to absorb carbon dioxide from the atmosphere to compensate. This cools the atmosphere further, creating yet more dust-producing regions, and the cycle continues, sinking Earth into an ice age.
When the planetary wobbles, known as Milankovitch cycles, eventually choke off the cooling, the feedback goes into reverse: continents warm, dust storms subside, the Southern Ocean is starved of iron, and CO2 levels in the atmosphere rise again.
Emphasis mine.
The iron dust was paid off by Big Oil. /sarc
That said, I’m shocked that NewScientist published this at all. They’ve been all-in on the CAGW bandwagon since I can remember.
And today the BBC is reporting this article: Arctic ‘tipping point’ may not be reached dispelling another piece of climate alarmism. Their study indicates that there was less sea ice a few thousand years ago than today, meaning that the chances of a positive-feedback loop causing a thermal runaway as sea ice melts is unlikely.
Dr Funder and his team say their data shows a clear connection between temperature and the amount of sea ice. The researchers concluded that for about 3,000 years, during a period called the Holocene Climate Optimum, there was more open water and far less ice than today – probably less than 50% of the minimum Arctic sea ice recorded in 2007.
But the researcher says that even with a loss of this size, the sea ice will not reach a point of no return.
“I think we can say that with the loss of 50% of the current ice, the tipping point wasn’t reached.”
The idea of an Arctic tipping point has been highlighted by many scientists in recent years. They have argued that when enough ice is lost it could cause a runaway effect with disastrous consequences.
“I don’t say that our current worries are not justified, but I think that there are factors which will work to delay the action in relation to some of the models that have been in the media.
“I think the effect of temperature and global warming may cause a change in the general wind systems which maybe will delay the effects of the rapidly rising temperatures a little bit.”
Frankly, if the Earth’s climate was subject to as many positive feedback loops as the warm-mongers claim, it would’ve ran away long ago. It seems the Earth’s climate is more stable than that. There’s a lot we still don’t understand about climate mechanisms. Any attempts to “stop climate change” could well have unintended consequences. Good intentions based on poor knowledge often have bad results, e.g. kudzu.
How can these computer climate models accurately incorporate the effects of things like plankton growth? What confidence do we have in projecting their population at any given time?
And if we can’t, then what justifies confidence in the climate models?
OMG!! The warnings I read back in the 70’s during middle school that the Earth was returning to an Ice Age are coming to pass!
Of course, one of the definitions of ice age is a period where the poles have ice caps year round, so I guess we’ve been there, done that, and bought the t-shirt
Jiminator: to coin a phrase, “Heh. Indeed.”
“Frankly, if the Earth’s climate was subject to as many positive feedback loops as the warm-mongers claim, it would’ve ran away long ago. It seems the Earth’s climate is more stable than that. ”
This is the heart of my skepticism.^^^
You have science. Then you have funding. Which do ya want?
Humans are so predictable.
It’s been known for a long time that feedback effects must have something to do with the ice ages, since the direct forcing from the Milankovich cycles is too weak. This feedback likely had something to do with CO2 levels. This work just seems to be proposing one mechanism for this feedback. The CO2, once in the atmosphere, would still be influencing temperature.
It’s not clear what this has to do with the current situation, unless you are proposing the current much more rapid CO2 increase isn’t due to fossil fuel (and to a lesser extent, standing biomass) combustion.