Four degrees of warming 'likely'

[hans]

Siberian permafrost thaw warning sparked by cave data

Evidence from Siberian caves suggests that a global temperature rise of 1.5C could see permafrost thaw over a large area of Siberia.

A study shows that more than a trillion tonnes of the greenhouse gases CO2 and methane could be released into the atmosphere as a result.

[chas]

This article (not available for free, I can only see the abstract) finds that the productivity for outdoor workers has already decreased by 10% in the last few decades due to increases in the wet-bulb temperature in hot climates, and will go down another 10% in the next 40 years and down to 40% by 2200.

I find this interesting, because last I knew, models indicate a much greater increase in temperature in the colder climates. But I guess because warmer climes are already close to the human tipping point, a small rise in temperatures accompanied with a significant rise in humidity is enough for the effect to be pretty significant.

[an seanduine]

I guess this is a corollary to "Only mad dogs and Englishmen. . . ."

Bob

[mutepointe]

On the positive side, some of the younger of us will have really great seats for the destruction of the earth. It will be almost like the restaurant at the end of the universe. Almost.

[Innocent Bystander]

http://www1.plymouth.ac.uk/marine/secch ... fault.aspx

There is some controversy over an apparent reduction in the numbers of phytoplankton, and whether this is associated with climate change.
This website is asking for sea-going volunteers to participate in an analysis project. Some of the Chiffy denizens are sea-going, and might like to consider it.

[hans]

US scientists report big jump in heat-trapping CO2
http://bigstory.ap.org/article/us-scien ... apping-co2

The amount of heat-trapping carbon dioxide in the air jumped dramatically in 2012, making it very unlikely that global warming can be limited to another 2 degrees as many global leaders have hoped, new federal figures show.

Scientists say the rise in CO2 reflects the world's economy revving up and burning more fossil fuels, especially in China.

Carbon dioxide levels jumped by 2.67 parts per million since 2011 to total just under 395 parts per million, says Pieter Tans, who leads the greenhouse gas measurement team for the National Oceanic and Atmospheric Administration.

In 2009, the world's nations agreed on a voluntary goal of limiting global warming to 3.6 degrees Fahrenheit over pre-industrial temperature levels. Since the mid-1800s temperatures haven already risen about 1.5 degrees. Current pollution trends translate to another 2.5 to 4.5 degrees of warming within the next several decades, Reilly says.

[hans]

Climate scientists have linked the massive snowstorms and bitter spring weather now being experienced across Britain and large parts of Europe and North America to the dramatic loss of Arctic sea ice.

"The sea ice is going rapidly. It’s 80% less than it was just 30 years ago. There has been a dramatic loss. This is a symptom of global warming and it contributes to enhanced warming of the Arctic," said Jennifer Francis, research professor with the Rutgers Institute of Coastal and Marine Science.

According to Francis and a growing body of other researchers, the Arctic ice loss adds heat to the ocean and atmosphere which shifts the position of the jet stream – the high-altitude river of air that steers storm systems and governs most weather in northern hemisphere.

"This is what is affecting the jet stream and leading to the extreme weather we are seeing in mid-latitudes," she said. "It allows the cold air from the Arctic to plunge much further south. The pattern can be slow to change because the [southern] wave of the jet stream is getting bigger. It’s now at a near record position, so whatever weather you have now is going to stick around," she said.

Read whole article: http://en.zistboom.com/2731?goback=.gde ... _229041598

[hans]

"More than half of common plant species and a third of animals could see a serious decline in their habitat range because of climate change.

New research suggests that biodiversity around the globe will be significantly impacted if temperatures rise more than 2C.

But the scientists say that the losses can be reduced if rapid action is taken to curb greenhouse gases."

"The scientists projected that if no significant efforts were made to limit greenhouse gas emissions, 2100 global temperatures would be 4C above pre-industrial levels.

In this model, some 34% of animal species and 57% of plants would lose more than half of their current habitat ranges. "

http://www.bbc.co.uk/news/science-environment-22500673

http://www.nature.com/nclimate/journal/ ... e1887.html

[I.D.10-t]

Totally thread drift and off topic...

It gets on my nerves when journalists use the word scientist. I wouldn't give two craps and a handshake for what a skatole researching chemist thinks of the weather. Even less if he was talking about the climate. If you don't know the difference, ask a "scientist".

[hans]

It gets on my nerves when journalists use the word scientist. I wouldn't give two craps and a handshake for what a skatole researching chemist thinks of the weather. Even less if he was talking about the climate. If you don't know the difference, ask a "scientist".

I don't mind if a journalist writes "scientists say ..." when referring to peer reviewed and published scientific research, it is the research which counts, and making research results accessible to a wider public is an important function for a science journalist. It is usually not about a personal opinion of a scientist, unless such is in connection to research.

[I.D.10-t]

I guess I just don't like the lack of precision. It is like when I see "Doctors say..." The lack of precision always seems like a marketer is trying to sell me something and conceal something else. I guess I've seen some really misleading reporting from some "respected" news sources. The word "scientist" is only used by journalists to give a sense of authority but it is a bit of a weasel word.

[hans]

Predicting the weather can never be precise, nor can predicting the changes of climate. There are inherent uncertainties. Still the trend seems clear enough, the dangers of non-action or later action very real.

But data can be precise, even though the consequences on the level of local weather are not:
Climate Milestone: Earth’s CO2 Level Passes 400 ppm
Greenhouse gas highest since the Pliocene, when sea levels were higher and the Earth was warmer.
http://news.nationalgeographic.com/news ... e-400-ppm/

Policymakers worldwide have been stymied in their effort to reach a global agreement on reducing fossil fuel emissions. Many scientists argue that the CO2 concentration must be stabilized at 450 ppm to avoid the worst impacts of climate change. Some activists argue for a more ambitious goal of 350 ppm. NOAA has not recorded an average monthly CO2 reading below 350 ppm at Mauna Loa since October 1988.

The last time the concentration of CO2 was as high as 400 ppm was probably in the Pliocene Epoch, between 2.6 and 5.3 million years ago. Until the 20th century, it certainly hadn't exceeded 300 ppm, let alone 400 ppm, for at least 800,000 years. That's how far back scientists have been able to measure CO2 directly in bubbles of ancient air trapped in Antarctic ice cores.

[chas]

A couple of remarks on that. In graduate school, someone often brought in a copy of the Weekly World News. They were always quoting a "top scientist", often someone allegedly from Albania or some other place with very limited contact with the US. (Example: "Top scientist concludes that moon is giant space creature's skull.") So we had T-shirts made up that just said "Top Scientist."

Also, for some reason journalists think that physicists are more respected or perceived as more trustworthy by the public. So a lot of journalists who like to sensationalize things have lists of crackpot physicists that they can cite when promoting some wacky idea. Bob Park once said something to the effect, "For every crackpot idea out there, a journalist can track down a PhD physicist who will corroborate it."

I agree that it's generally more useful for the reporter to cite the scientist's specialty. Chemist is clearer than scientist, polymer chemist is more clear than chemist.

I read yesterday that CO2 passed the 400 ppm mark last Friday at Mauna Loa. (crossed with Hans's post).

[I.D.10-t]

"Top Scientist."

This is for all of the top scientists out there.

[hans]

'Best estimate' for impact of melting ice on sea level rise

"Researchers have published their most advanced calculation for the likely impact of melting ice on global sea levels.
The EU funded team say the ice sheets and glaciers could add 36.8 centimetres to the oceans by 2100.
Adding in other factors, sea levels could rise by up to 69 centimetres, higher than previous predictions.
The researchers say there is a very small chance that the seas around Britain could rise by a metre."

http://www.bbc.co.uk/news/science-environment-22527273