Are we seeing a trend toward greater heat absorption by the Pacific?
In Global warming is unpaused and stuck on fast forward, new research shows that climate change is manifesting differently. After the super El Niño of 1998, deep oceans have been absorbing more heat. Trenberth's research puts the estimate of absorbed energy equivalent to more than 6 Hiroshima atomic detonations per second instead of of 4. This casts doubt on studies that gave a lower estimate to the Earth's climate sensitivity to greenhouse gases. The Earth system isn't in equilibrium, in effect it's shifting gears.
… the main point of the paper is that global warming is stuck on fast forward.
… after the massive El Niño event in 1998, the Pacific Ocean appears to have shifted into a new mode of operation. Since that time, Trenberth's research has shown that the deep oceans have absorbed more heat than at any other time in the past 50 years.
Trenberth and Fasullo's new paper also casts doubt on the conclusions a few recent studies that estimated the Earth's climate is less sensitive to the increased greenhouse effect than previously thought. These studies have been based on measurements of recent climate change, including the warming of the oceans.
However, the type of approach taken by these studies suffers from some significant drawbacks. Mainly the size of the cooling effect due to human aerosol pollution remains highly uncertain, and while the oceans have been warming rapidly, just how rapidly is another unsettled question.
Previous estimates put the amount of heat accumulated by the world's oceans over the past decade equivalent to about 4 Hiroshima atomic bomb detonations per second, on average, but Trenberth's research puts the estimate equivalent to more than 6 detonations per second. Trenberth and Fasullo note that using their ocean heating estimate by itself would increase the equilibrium climate sensitivity estimate in the paper referenced by Ridley from 2°C to 2.5°C average global surface warming in response to a doubling of atmospheric carbon dioxide, and using other more widespread accepted values would bring the estimate in line with the standard value of 3°C. They thus note, "Using short records with uncertain forcings of the Earth system that is not in equilibrium does not (yet) produce reliable estimates of climate sensitivity." [emphasis mine]
Meanwhile, in Climate change to make 'Super El Nino' events twice as likely, we learn that Australian researchers find extreme versions of El Niño, called Super El Niño, will occur twice as often as climate warms.
AUSTRALIAN RESEARCHERS have found that extreme versions of the cyclical weather pattern El Niño — dubbed 'super El Niños' — will double in frequency under projected global warming scenarios, with repercussions for many countries across the globe.
In a collaborative effort, scientists from the national science agency CSIRO and the Australian Bureau of Meteorology used statistical modelling to uncover how global warming influences the super El Niño.
"Using these models we confirmed, even under modest global warming scenarios, these unusual El Niño events doubled in frequency," said Santoso.
"Our results show that a warmer climate will increase the probability for the occurrences of super El Niños, and lead to a higher probability for associated extreme weather."
If we put these findings together, doesn't it hint at yet another destabilizing positive feedback?
Some authors express the short-sighted view that deep oceans absorbing heat is good for land-dwellers such as ourselves. Any process that accelerates the future development of a stratified Canfield Ocean, anoxic at depth, horrifies me.
Anoxia increases from warmer water, and from decreased Thermohaline Circulation (which has already started in the Southern Ocean), and from decreased phytoplankton (already 40% lower in the Southern Ocean). If areas of anoxia proliferate, they'll deplete the global ocean system of bio-available nitrogen necessary for all marine life.
We're won't just be just killing off vertebrates such as whales and bony fish. If a stratified partly anoxic ocean develops in the future, we're talking very serious extinction event. As in Permian extinction, where nearly 97% of all living things died, the sky would turn green and oxygen levels would sharply drop. See Under a Green Sky. Anoxic ocean bacteria released hydrogen sulfide, a toxic gas, during the Permian extinction.
Some climate scientists consider the probability of widespread ocean anoxia moderate.
Will an overheating climate cause more Super El Niño's, which shift ever more excess heat into the Pacific? Will we keep discovering we'd underestimated Earth's climate sensitivity again, and again, as our planet Eaarth lurches toward a new equilibrium?
Time will tell. Only by bringing fossil fuel business-as-usual to a halt can we prevent future generations from this possibility.
More immediately, warmer water is increasing sea snot explosions, that also deplete oxygen in the deep ocean.
I don't "Like" these facts, but appreciate both the alert, and the vivid illustrations!