Researchers find models must account for volcanic eruptions to accurately predict climate change.
From:MIT Joint Program on the Science and Policy of Global Change
By the late 1990s, scientists had observed more than two decades of rapid global warming, and expected the warming trend to continue. Instead, despite continuing increases in greenhouse gas emissions, the Earth’s surface temperatures have remained nearly flat for the last 15 years. The International Panel on Climate Change verified this recent warming “hiatus” in its latest report.
Researchers around the globe have been working to understand this puzzle — looking at heat going into the oceans, changes in wind patterns, and other factors to explain why temperatures have stayed nearly stable, while greenhouse gas concentrations have continued to rise. In a study published today in Nature Geoscience, a team of scientists from MIT and elsewhere around the U.S. report that volcanic eruptions have contributed to this recent cooling, and that most climate models have not accurately accounted for the effects of volcanic activity.
“This is the most comprehensive observational evaluation of the role of volcanic activity on climate in the early part of the 21st century,” says co-author Susan Solomon, the Ellen Swallow Richards Professor of Atmospheric Chemistry and Climate Science at MIT. “We assess the contributions of volcanoes on temperatures in the troposphere — the lowest layer of the atmosphere — and find they’ve certainly played some role in keeping the Earth cooler.”
There are many components of the Earth’s climate system that can increase or decrease the temperature of the globe. For example, while greenhouse gases cause warming, some types of small particles, known as aerosols, cause cooling. When volcanoes erupt explosively enough, they enhance these aerosols — a phenomenon referred to as “volcanic forcing.”
“The recent slowdown in observed surface and tropospheric warming is a fascinating detective story,” says Ben Santer, the lead author of the study and a climate scientist at Lawrence Livermore National Laboratory. “There is not a single culprit, as some scientists have claimed. Multiple factors are implicated. The real scientific challenge is to obtain hard quantitative estimates of the contributions of each of these factors to the so-called slowdown.”
The researchers verified the cooling phenomenon by performing two different statistical tests to determine whether recent volcanic eruptions have cooling effects that can be distinguished from the intrinsic variability of the climate. The team found evidence for significant correlations between volcanic aerosol observations and satellite-based estimates of both tropospheric temperature and sunlight reflected by the particles off the top of the atmosphere.
“What’s exciting in this work was that we could detect the influence of the volcanic aerosols in new ways. Using satellite observations confirmed the fact that the volcanic particles reflected a significant amount of the sun’s energy out to space, and of course losing energy means cooling — and the tropospheric temperatures show that too,” explains Solomon, who is also a researcher with MIT’s Joint Program on the Science and Policy of Global Change. “There are still uncertainties in exactly how big the effects are, so there is more work to do.”
Alan Robock, a professor of environmental sciences at Rutgers University and a leading expert on the impacts of volcanic eruptions on climate, says these findings are an important part of the larger climate picture. “This paper reminds us that there are multiple causes of climate change, both natural and anthropogenic, and that we need to consider all of them when interpreting past climate and predicting future climate.”
“Since none of the standard scenarios for evaluating future global warming include volcanic eruptions,” Robock adds, “this paper will help us quantify the impacts of future large and small eruptions when they happen, and thus better interpret the role of humans in causing climate change.”
This research was led by a team at Lawrence Livermore National Laboratory and builds upon work Solomon conducted in 2011, finding that aerosols in an upper layer of the atmosphere — the stratosphere — are persistently variable and must be included in climate models to accurately depict climate changes.
The research was supported by the U.S. Department of Energy.
h/t to Roger Sowell
For reference, here is the associated paper; (h/t Greg)
http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2098.html
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Has the heat stopped hiding in the deep oceans?
Bottom line: “All warming is man-made and all cooling is natural fluctuations. It’s all right there in the models (except the natural part).”
Horse pucks. Aerosol load depends on where you measure it. The most important component of equatorial load comes from Africa. Ben has no idea what he is talking about. Am responding from my phone. There is plenty of research on this topic and I doubt Ben took serious stock of it. Will add comments later when I have a computer screen in front of me.
“Bill Strouss says:
February 23, 2014 at 9:22 pm
How about clouds? Seems that variations in cloud cover would cause wide swings in temperature, I’ve heard the models don’t take into account cloud variability, go figure, I guess the computations would get complex. Not to mention the monitoring, and quantifying of cloud variability would be tedious.”
Observed cloud cover over the period 2002-2014 is trendless.
I hate to point out the obvious, especially after pages of replies, but it’s simple logic… If there have been 15 years of little or no volcanic eruptions and this has ceased the warming trend, that suggests before this hiatus there were volcanic eruptions that were at least partially if not wholly responsible for the warming trend,,, Aha! Does this mean the warming of the 20th century was volcano driven and not CO2 driven? It seems you can’t have it both ways. There was either enough volcano driven heat to keep the warming trend alive, until it stopped, or there wasn’t enough and then volcano’s can’t explain the warming trend ending…
Haven’t they already claimed that global warming will increase the frequency and severity of volcanic eruptions? That makes this a NEGATIVE feedback mechanism.
“hard quantitative estimates …”
FFS.
“The recent slowdown in observed surface and tropospheric warming is a fascinating detective story,” says Ben Santer, … “There is not a single culprit, as some scientists have claimed. Multiple factors are implicated…”
Well then, Mr. Santer, could not multiple factors have been implicated in the increase in atmospheric temperatures that occurred prior to 1998? Or, did the bulk of the evidence suggest a discernible human influence back then and no further detective work was required in those good old days of world transformationdom?
Santer gives the game away when he says, ““There is not a single culprit, as some scientists have claimed. Multiple factors are implicated. The real scientific challenge is to obtain hard quantitative estimates of the contributions of each of these factors to the so-called slowdown.” [Bold mine]
The use of the word “culprit” in this context is interesting, It’s as if he’s off on a Holmesian search for the perpetrator of a crime- in this case, the crime of falsifying AGW.
He will find some way to confirm the theory in his eyes. Because the idea that the climate is self-adjusting or that greenhouse gases are far more benign than previously understood can’t enter into it. He’s got to find his culprit
It’s a set up for a new “volcano tax.” Sequestering volcanoes is going to be expensive…. 🙂
What are two well known gases that volcanos emit when they erupt (and often vent continually when they are not actively erupting)? Come on warmists….you can say them….methane and C02!
Good scientists! Now, here’s a toughie….if volcanos are ejecting enough particulate matter to actually affect the global temperatures negatively…is it possible that they can also eject enough GHGs to affect the global temperatures positively? In real science, “underestimations” cut both ways.
Oh, and if more sunlight has been blocked by particulates than we thought, then less sunlight was available to heat the oceans. Make sure you re-adjust your math “estimates” in the models there too.
Nice try, Hoser. It was a very simplified graphic that omitted other reactions for clarity, since carbon dioxide is not implicated in noctilucent cloud formation.
Anthropogenic compounds eventually migrate to the polar atmosphere, which is how CFCs ended up there, causing (or not causing) the “ozone hole.”
Methane from a wide variety of sources (manure, landfills, gas drilling/transport etc.) is widely distributed in the atmosphere including the poles. We observe high concentrations of chlorinated hydrocarbons in the Arctic, this may be due to reactions of chlorides from seawater (discussed on WUWT) with reactive methane.
http://www.ccpo.odu.edu/~lizsmith/SEES/ozone/class/Chap_10/10_3.htm
Allan M.R. MacRae says:
February 24, 2014 at 3:10 am
Ed Zuiderwijk says: on February 24, 2014 at 2:55 am
“Ed, writing a poem about the hiatus is difficult, as there are few if any words that rhyme with hiatus.
A Scottish friend wrote a song extolling the virtues of haggis – same problem. :-)”
Any poet worth his salt…. how about “high flatus” from Benny S. on arseho..er no .. aerosols. All this volcanic “flatus” will “dilate us”.
And haggis it will “gag us” because its really a “coprophagus” (slag us, bag us, drag us,..) I hope I have helped.
Oh and probably the aerosols from submarine volcanoes are largely “scrubbed” out by the sea water, so they shouldn’t be much help.
Climate…it’s just one damn thing after another, isn’t it?
Mr Santer may finally be realizing An Inconvenient Truth …
Actually all y’all have it backwards.
Volcanoes add to global warming.
1 – they inject large amounts of CO2 into the atmosphere.
2 – they inject large amount of dust into the atmosphere. Dust that settles out on the white snow causing it to melt faster, changing the color of the earth from white to dark increasing the take up of electromagnetic radiation of the earth which causes more energy to be released which is then captured by the extra CO2. That is the process that add heat to the atmosphere.
Now, we are flushing more money down the toilet with “revelation” studies chasing after “the” reason or reasons for the stalled warming.
Everything continues to be based on the original theory of catastrophic global warming being right(and their reputations intact) and rather than just state, “OK, the global climate models and theory had some serious chinks” the response is to back up the theory with newly discovered science that not only will show they were right in the first place, but now, they are so smart as to be able to provide the world with the secret reason being the warming stall that nobody knew before.
The reality is that even if their reason is/was correct, it means their theory is wrong. If the natural response of the oceans, atmosphere and sun is causing temperatures to not go up for 15 years(after also cooling a bit for 30 years before the 80’s/90’s warming), then it’s clear that whatever the reason they give……………………..the system, for decades at a time is driven by whatever reason they give and during that time, CO2 takes a back seat.
In fact, if whatever reason they give is offsetting the warming right now, it means that the whatever reason they give was likely enhancing the warming(80’s/90’s) when it’s effect was the opposite as it is now.
That is proof that CO2 is not as powerful of a climate driver as theorized.
Good news for drought stricken California. Some hefty rains coming later this week.
Not drought busting but very welcome.
Maybe we should call this “The Obama effect”.
Like when Al Gore went to Washington to speak about global warming and the place got shut down by a blizzard, Obama’s recent visit to California to intensify the spell/brainwash in peoples minds that everything, including the California drought is from humans spewing carbon pollution(known to authentic scientists as a beneficial gas that is boosting plant growth and world food production by 15%)
Now we have rain on the way.
BTW, California had a severe drought also in the WInter of 76/77 which also featured the circumpolar vortex temporarily dropping extremely far south(into the US and S.Canada) bringing extreme cold to the Eastern 2/3rds of the US.
The PDO was near the end of its 30 year cycle when it was negative most of the time(followed by being positive in the 80’s/90’s).
The PDO, right on schedule has returned to being negative.
Expect more of these type of Winters.
Speaking of the Obama effect. Thanks to the EPA declaring CO2 as pollution, they can regulate it however they want. In this case, it means shutting down as many coal fired power plants as possible………..which is already happening.
Who thinks that our country needs MANY less power plants generating electricity for residential heating if the next couple of decades will have these type of Winters more often than we did in the 80’s/90’s?
This administration is aggressively taking complete control of our energy policy based on an agenda to fight global warming and make us believe in the human caused climate change boogy man that only exists in the minds of those that have fallen into the trans of an idea with no support from the real world and science.
Take note that these explanations for why the warming stalled are all coming AFTER the warming stalled. Not one of them was predicted or even considered BEFORE the warming stalled.
Take note also, that AFTER our Winters in North America took a turn towards increasing snow in the mid 2000’s, then they claimed that global warming puts more moisture in the atmosphere and caused bigger snowstorms and blizzards. Not one of them predicted or even considered this before hand(the prediction was that our future world would feature no snow for its children)
Take note also, the AFTER we had record breaking cold this WInter in the US, Obama’s climate science expert produced a marketing video to explain how we should expect more extreme cold because of global warming. Why were we never told this before hand?
Reason. None of it was predicted before hand, just like the theory of CAGW is being crushed by real world empirical data and authentic science. They were wrong about almost every prediction but hindsight is always 100%.
So the marketing brainwash is to use hindsight and come up with a convincing sounding explanation for why every extreme weather or climate event WAS caused by humans burning fossil fuels.
They already have a massive amount of people convinced. Once a person thinks they know something their brains will easily accept new information that confirms what they think they know and it gets stored in their brains as knowledge.
It’s 10 times harder to convince that person that they are wrong about what they think they know. They will reject things that contradict what they think they know…………..even if they are dead wrong about their belief and the evidence showing that they are wrong is compelling and placed in front of them.
“ALL-CLEAR IN THE STRATOSPHERE: Earth’s stratosphere is as clear as it’s been in more than 50 years. University of Colorado climate scientist Richard Keen knows this because he’s been watching lunar eclipses”
http://spaceweather.com/archive.php?view=1&day=19&month=12&year=2010
“The lunar eclipse record indicates a clear stratosphere over the past decade, and that this has contributed about 0.2 degrees to recent warming.”
Did they just delete the two big events to make the aerosol release from 2000-2013 look big?
I went back and looked at 1950-1999 vs 2000-2013; more moderate ones recent but more big ones in the past.
Is this just doctoring the historical down to make recent data look big?
http://en.m.wikipedia.org/wiki/List_of_large_volcanic_eruptions_of_the_21st_Century
Compare the reduction in sulphur dioxide emissions resulting from the implementation of the 1990 Clean Air Act with the increase in SO2 from the eruption of Pinatubo.
Pinatubo – 17mm ton increase
Clean Air Act – 12mm ton decrease EVERY YEAR
http://en.wikipedia.org/wiki/Mount_Pinatubo
http://www.epa.gov/airmarkets/quarterlytracking.html
European environmental regulations preceeded ours by about 10 years, and caused similar decreases in SO2 emissions in the 1980s.
Let’s put it all together, if you are reading this blog you now know the answer. The EPA and Congress (and European regulators) caused all the global warming in the late 20th century. The global cooling in the 1960s and 1970s was caused by the gradual increase in SO2 as the world industrialized and electricity generation using coal increased. When we cleaned out the SO2 temperatures went back up. But now guess what?? China put 50 coal fired power plants online in the last year. The EPA wants to undo the effects of their prior regulation by regulating something else… and as our dear leader said, “under my plan electricity prices would necessarily skyrocket”.
OK, so where does this leave the previous “explanations” for the lack of warming?
It’s hiding in the deep ocean
It’s because we’ve not included the arctic properly
??????????????????????
I am waiting for Katla to cut loose as it sometime does, to add to the misery of a cooling climate.
Words and excuses from the officialists will have little meaning to the Europeans at that point.