These posts include a brief mention of a number of news items relating to climate change. They don’t preclude treating any of these topics at more length in a separate post.
They can also serve as an open thread so that we can keep each other informed on important climate news.
Clouds and climate sensitivity
Climate sensitivity is the temperature increase caused by a doubling of the trace gas CO2 in the atmosphere. The IPCC AR4 gave this as between 2 and 4.5 °C for short term “Charney” feedbacks, which is a large uncertainty range for such an important number. Clouds are largely to blame.
Recent research indicates less cloud cover as the sea surface warms. Thus uncertainty is taken away from the low side.
Gavin Schmidt of NASA GISS says:
what’s needed are models with even finer detail, and data on all different kinds of clouds. Nevertheless, evidence is building for a warming influence from cloud changes: Clement’s research shows that when the sea surface is warm there is less low cloud cover.
That’s right. Schmidt’s boss, James Hansen, using paleoclimate data, reckons the value for shorter term climate sensitivity should be 3C plus or minus 0.5C (see Storms of My Grandchildren) based on paleoclimate data. Hansen reckons that full climate sensitivity is more like 6C, pointing out that there was about a 5C differential between now and the last ice age. He also says that climate sensitivity is not constant for all climate states. As we warm he thinks it will increase.
Global warming shares the blame for Europe’s cold weather
That is according to Vladimir Petoukhov, a climate scientist at the Potsdam Institute for Climate Impact Research in Germany.
He says there are two main causes. One is a positive North Atlantic Oscillation (NAO) and the other low levels of sea ice in the Barents-Kara Sea, north of Norway and Russia. These two phenomena interact with and amplify each other. The latter is caused by global warming.
Other causes include reduced solar activity and changes in the Gulf Stream but are less strongly correlated.
Please note Petoukhov is not predicting the coldest European winter in 1000 years, nor is any other scientist. A story to that effect seems to have originated in a Polish tabloid newspaper, which made it up.
Arctic ice volume as of last September has never been lower
Climate Progress has a look at Arctic ice volume story.
Tamino, back in October, dealt with Arctic ice area which turned out to be the third lowest in modern times and smack on his longer term declining trend.
Veron on the world’s coral reefs
Climate Progress also features John “Charlie” Veron on the grim future of coral reefs this century.
the science is clear: Unless we change the way we live, the Earth’s coral reefs will be utterly destroyed within our children’s lifetimes.
On our current trajectory of increasing atmospheric CO2, we can expect that by 2030 to 2050 the acidification process will be affecting all the oceans of the world to some degree. At that point, the relatively cool, deep-water tropical regions that have offered refuges to corals from temperature stress will be those most affected by acidification.
The atmospheric levels of CO2 we are already committed to reach, no matter what mitigation is now implemented, have no equal over the entire longevity of the Great Barrier Reef, perhaps 25 million years. And most significantly, the rate of CO2 increase we are now experiencing has no precedent in all known geological history.
Reefs are the ocean’s canaries and we must hear their call. This call is not just for themselves, for the other great ecosystems of the ocean stand behind reefs like a row of dominoes. If coral reefs fail, the rest will follow in rapid succession, and the Sixth Mass Extinction will be upon us — and will be of our making.
We won’t get a four metre sea level rise the but threat to tropical forests is ‘greater than suspected’
That’s according to a new review of climate predictions by the Hadley Centre.
Alaskan wildfires threaten runaway climate change
That’s according to a new study:
This is the first study to reveal that fires in the Alaskan interior – an area spanning 18.5 million hectares – have become more severe in the past 10 years, and have released much more carbon into the atmosphere than was stored by the region’s forests over the same period.
The carbon sink is becoming a source.
It’s crawling with life down there
For something a little different, John D sent me this link about an extensive biological community living in porous rock deep beneath the seafloor in the basalt layer. The pool of organic carbon down there is about the same size as the pool of atmospheric carbon dioxide. This alters our ideas of the oceanic carbon cycle.
I was reminded of a similar article in the New Scientist where they found life in the gabbroic layer below the basalt.
And back on the local scene
Two climate change activists chained themselves to a conveyor belt carrying coal to one of Australia’s largest power stations on Saturday, temporarily shutting the belt down.
Xstrata said its own mining operations had not been disrupted, but at least they tried.