Are we sure CO2 is the only explanation for recent warming?

Question

We now have a very good explanation for the warming since the late 70s. And that explanation is the Southern Oscillation Index (SOI).

"This is scientific research, not an opinion." - Co-Author Chris de Freitas

Commentary: http://www.climatedepot.com/a/2117/PeerReviewed-Study-Rocks-Climate-Debate-Nature-not-man-responsible-for-recent-global-warminglittle-or-none-of-late-20th-century-warming-and-cooling-can-be-attributed-to-humans

Full text: http://climatedebatedaily.com/southern_oscillation.pdf

Answer 1

Yes, we are sure it's responsible for the vast majority of the recent warming.



And no, this study does not support the conclusion that SOI accounts for any of the global warming since 1970. They managed to slip in a statement that ENSO "perhaps" accounts for some of the warming trend even though their research in no way supported this statement. In fact, the way they did their data analysis, they literally could not have made that conclusion, because they removed all effects of long-term trends in their data (they were examining temperature variability, not long-term trends). Unfortunately whoever peer-reviewed this study fell asleep at the helm and let them leave this completely unsupported "perhaps" statement in the conclusion. As they say, peer-review is necessary but not sufficient to ensure that a journals are only publishing quality science.



And so the denial blogosphere went nuts. Bob Carter - one of the co-authors - made some statements that their research showed ENSO causing the warming trend even though again, their research showed no such thing. The error was so obvious that a rebuttal paper was published in record time.

http://climateprogress.org/2009/08/06/journal-of-geophysical-jgr-denier-paper-enso-pacific-ocean-rebuttal/



We discussed the SOI paper in several previous questions. A few linked below, and also here:

http://www.ecohuddle.com/forum/thread/1637/carter-et-al-skeptical-climate-science-in-a-nutshell#post_9583



*edit* agreed with Dawei - there is nothing "vengeful" about reactions to this paper. They threw in a conclusion which was in no way supported by their research. Not only was it a conclusion which their research could not possibly have supported, but it's a physically impossible theory. Oscillations like ENSO cannot cause a long-term warming trend. For one thing they're oscillations, switching between cool and warm states. For another they neither create nor retain heat, they simply move it around between oceans and air.



This paper is unquestionably bad science. Bad science is bad science, regardless of your opinions on AGW. If you can't admit that, you can't call yourself a skeptic.

Answer 2

Increase levels in Carbon Dioxide is not the only thing that contributes to Global Warming. There are other Greenhouse Gases like Nitrous Oxide and Methane. Scientist believe that the main cause of Global Warming is the skyrocketting levels of Greenhouse Gases in the Atmosphere in the planet Earth.



Deforestation is also another cause for Global Warming. Plants like Trees take in Carbon Dioxide and releases Good gases like oxygen.



A cows digestive System produce the greenhouse gas called Methane which is more than 20 times powerful as a Greenhouse gas than Carbon Dioxide.



We need to reduce the amount of Greenhouse gases that us Humans put into the Atmosphere. This is the best way to keep the earth more balance in temperature.

Answer 3

I think we are missing the big picture here.



Science will have differing theories as it always does. In the end one theory will become basis of all theories to come. We might already be there or we might not. It is part of the scientific method many posters here seem to forget. Different opinions are not only good but are necessary for good science.



Fact We have a very small sample of world temperatures.



Fact As the money is poured into this research will will have more differing opinions from the scientific community.



Fact The data will improve as more research is done.



Part of the big picture I think that gets lost is there is no downside to trying to reduce our carbon emissions. Who knows what scientific discoveries will come out of this effort. Remember the space program. It delivered far more than pretty pictures from the moon.



Relax. Don't be so in love with your theory that you might miss the truth. Give the opposition a chance they might be right. And I am addressing both sides of the argument.



off the top of my head scientific theories that were given allot of press



cold fusion had been accomplished



cocaine is not addictive



the egg is bad for your health



We are headed for another Ice Age



California is going to fall into the sea



lighten up folks the ride has just begun.

Answer 4

There is still much uncertainty in the TSI record from 1980 to 2000, in fact Scafetta has a new paper that shows that if the ACRIM composite is used in climate modeling that the sun can account for as much as 65% of the warming from 1980 to 2000. The PDO cycle shift is undeniably linked to 30 year cooling and warming cycles, its amazing that some of these individuals can blatantly make the statement that ENSO has been carefully considered, when there is not a single human on the face of this planet that could predict with any accuracy as to why and when the next La-Nina or El-Nino will occur.



http://wattsupwiththat.com/?s=Scafetta

Answer 5

It would be difficult to escape atmospheric physic's other then CH4. But hey! most of the climate is a derivative of ocean pressure and temperatures. From what little I understand with the exception of Northern latitudes almost nothing is known about deep ocean pressure and temperature gradients. How in the Heli can can someone explain a molecular change occurring and reoccurring in less then a tenth of a second? Even if they could it would have almost no substance to climate predictability. Why do you think most climatologist limit themselves to SS T's? The climate your getting today may be a influence from 280-10 yrs ago or longer. I just wish someone would put this in a realist perspective. http://www.encyclopedia.com/doc/1G2-3409400230.html



Yep! you can find arguments from reliable sources that contradict each other. I'm getting use to the rhetoric.

Answer 6

The authors of that paper first ran the data through a moving-average (lowpass) filter, then differentiated it (highpass filter). The moving-average filter in combination with the differentiation operation was, in effect, a bandpass filter -- with a passband corresponding to the SOI frequencies!



It should not be surprising that temperature data run through a bandpass filter with an SOI passband would correlate highly with SOI data.



It's rather like running the The White Album through a 60 Hz filter and then concluding that Beatles music is mostly 60 Hz line noise.





Edited to add: According to OttawaMike's profile, he has degrees in electrical engineering (EE). He should know that the derivative operator acts as a high-pass filter that effectively removes the long-term trend component (in this case, the global-warming signal). This is one of the first concepts that EE students learn in college.



He should have absolutely no trouble understanding that differencing the temperature data (as the authors did prior to the SOI correlation) will effectively erase the global-warming signal.

Answer 7

Mike,



I know from your questions and answers that you're an intelligent person who knows a good deal about global warming / climate change. However, it strikes me that you're making the same mistake that many skeptics and deniers make in that they look only at a very small part of a very large and complicated picture.



By adopting that approach it's possible to 'prove' that the world is flat and that we don't actually exist.



It is imperative when considering the causes and consequences of global warming that all possible explanations are taken into consideration and are duly accounted for in any calculations or conclusions.



ENSO (and many other factors) has been carefully considered, it's effects have been established as far as is reasonably practicable.



There is certainly much that we have yet to learn about ENSO but one area in which we can confidently say that we know more than enough concerns it's contribution to global warming. Undoubtedly it has a role to play but the positive forcing is minor and very short lived and in no way accounts for the warming that we have witnessed in recent decades.



Unfortunately, there are many people who can write what appears to be a well researched and credible report (such as the ones you refer to) but on closer inspection it is immediately apparent that these reports are deliberately biased and are not in any way based on sound scientific principles or validated by reliable evidence.



Have you never wondered why the skeptic community constantly comes up with one report after another? It's because the longevity of each report they produce is negligible, within hours of publication it's ripped to shreds and not even it's authors refer back to it.

Answer 8

If CO2 is the only explanation for recent warming, why does the ETS tax farmers for the methane generated by their livestock? Why are naturally generated greenhouse gases taxes at all - because they are more effective GG's than the feeble CO2. We have managed to increase Global atmospheric CO2 since pre-industrial times by a pathetic 40%. Most real climate scientists (Meaning Meteorologists and Geologists, not Economists and Socialists) agree that doubling the CO2 concentration would warm the atmosphere by approximately 1Degree Celsius which is easily masked by other factors, such as the SOI, and solar activity.

In short we do not have the power to generate enough CO2 to seriously warm the planet by more that 1 degree.

So why tax Carbon? Because it generates revenue, like any other tax.

If taxing farmers for the flatulence of their cattle is a good idea, why are we not taxing the third world for their farting Elephants and Wildebeestes? Because it is a cash grab by Bureaucrats from their own citizens - it's a pretence for increased taxation.

Answer 9

I think this show the poor understanding of the scientific process displayed by many deniers

"As is expected with all studies of this nature, alarmists rebuttals are swift and vengeful."

Any published paper can and does have rebuttals published in any field of science the fact is some elements of GW do have weakness, but it also true that weakness don't make the theory incorrect, and certainly nothing produced by the few numbers of papers those like Carter or Lindzen have managed to get published have even come close to producing any real evidence. except when more strongly worded papers are published in energy & environment, which is only to be expected when denier groups have gone to the trouble of setting up their own pretend peer reviewed journal.

Answer 10

Look at the raw data for yourself. See if the El Nino/ La Nina variations in the last 25 years look like a plausible reason for global warming.

Answer 11

scientists can never say "we are 100% sure", therefor their theories are always viewed as doubtful whereas they are in fact highly likely to know.



C02 is not the sole culprit



SOI refers to El nino and the frequency of that, it is not an reason for global warming (or should i say climate change) it is merely an indicator of change.

Answer 12

Oh come on, not the ENSO hypothesis.



The authors of that paper eliminated the warming trend in the temperature records, and THEN they examined the correlation between temperature and ENSO. Then, after that, they tried to say that ENSO explains the warming trend (which they had already eliminated from the data.) Do you not see the disconnect there?



All they showed was that ENSO affects short term temperatures. This, as Tamino says, is very old news which no one really denies.

http://tamino.wordpress.com/2009/07/24/old-news/



To answer your question however, CO2 is not the only possible explanation. It is just the best explanation available. The backwards logic presented in this paper is one of the worst.

Answer 13

CO2 is a greenhouse gas. Greenhouse gases cause warming. Since we have increased CO2 by about 40% since pre-industrial times, we are causing the Earth to warm up. It's pretty straightforward really. You can't increase the greenhouse effect and *not* cause more warming, unless there is some kind of counterbalancing negative feedback, which there isn't.



What's particularly striking from your cited article is that the SOI clearly doesn't account for *any* of the long-term change in global tropospheric temperature anomalies (GTTA), which refutes any assertion that the SOI explains the global warming of the last 30 years. It only tells us what we already know - i.e. that ENSO has a large influence on the short term interannual variations in global temperature but cannot account for any of the long term warming trend, which is due principally to human output of greenhouse gases.



In summary, the article supports AGW.

Answer 14

well CO2 is only one of the many reasons why global warming is occuring...

people also turn to methane, cutting down trees and oil spills that are messing up our ocean currents

Answer 15

I would be very careful if I were you. People who have made common sense remarks like that have been targeted for lawsuits by radical leftist. If you had influence like Dr Lindzen you would have to go to court for daring to speak such blasphemy. Common sense is the worst enemy of the AGW doomsday cultist. I had to add that to discredit myself even though it is true. Those that are wacky enough to buy significant AGW might take me seriously and have no idea when I am just making a point. You have forced dana to come out in many of his various alias to counter what you said. It is indeed a threatening statement.