There's an article on the climate conspiracy blog, WUWT, which illustrates the tunnel vision or selective bias of deniers. It is another example of blatant cherry-picking. Eric Worrall repeated nonsense that he read on a denier website (archived here). He wrote about a recent publication from the UK Met, which has the title:
UK Met: "Changes Underway in the Climate System?"
The misleading headline at WUWT reads:
That's right. Compare the two titles. The UK Met booklet is suggesting there may be big changes underway, while the WUWT article is suggesting the Met Office is saying there'll be more of the same.
Telltale Technique No. 4: Cherry picking
Eric's article plucked out of the booklet part of the section about the Atlantic Multidecadal Oscillation (AMO), writing how it may be about to enter a cool phase. That's called cherry-picking and is Telltale Technique No. 4 of climate science denial.
About the North Atlantic
The AMO index is used to indicate changes in the pattern of sea surface temperature in the North Atlantic. This mainly affects precipitation and land surface temperature in western Europe and parts of North America. It doesn't have as big an impact on global mean surface temperature as does the Pacific. Here is the segment of the report that Eric copied and pasted:
Observational (Folland et al. 2013) and model (Knight et al. 2005) estimates further suggest AMO shifts have an effect on global mean near-surface temperatures of about 0.1˚C. A rapid AMO decline could therefore maintain the current slowdown in global warming longer than would otherwise be the case.As I understand it, the 0.1 ˚C estimate is from the peak to the trough of the AMO. What Eric didn't mention was the much larger Pacific Ocean. The UK Met report suggested that the Pacific Decadal Oscillation might be shifting from a cool phase to a warm phase (which has been discussed here before on more than one occasion).
Faster warming quite likely
In its summing up, the UK Met Office wrote that it's going to be hot this year and next, and it's likely to warm much faster again within two years:
Changes are occurring in some of the leading patterns of global climate variability, altering the risk of regional climate impacts worldwide and affecting decadal rates of global warming.
El Niño is now well underway and is growing in strength. This is likely to have widespread regional impacts and to continue to contribute to raised global average temperatures this year and next year.
On longer timescales, the Pacific Decadal Oscillation has been negative in recent years and this has been linked to a slowing of the rate of global warming. Changes in the North Pacific suggest that the PDO may now be entering its positive phase, but because understanding of what drives the low frequency behaviour of the PDO is limited and its predictability appears to be low, a definitive statement on its future state is not yet possible.
The Atlantic Ocean has been warm in recent years but is now showing the first signs of a switch to cooler conditions, consistent with observed changes in the deeper ocean circulation. Widespread impacts around the Atlantic basin are likely if this continues.
While global surface warming slowed from the end of the 20th century, our best estimates of global mean temperature for 2015 are at or near record levels, and this is consistent with climate predictions for similarly high values that we made last year (http://www.metoffice.gov.uk/news/releases/archive/2014/2015-global-temp-forecast). Record or near record temperatures last year and so far this year, along with the expected warming effects of El Niño, mean that decadal temperature trends are likely to increase. Barring a large volcanic eruption or a very sudden return to La Niña or negative AMO conditions which could temporarily cool climate, ten year global average warming rates are likely to return to late 20th century levels within the next two years. Nevertheless, the slowdown in warming is still an active research topic and trends over a longer (15 year) period will take longer to respond.
Further long-term global warming is expected over the coming decades but variations of climate worldwide from year to year or decade to decade will always depend on the subsequent variations in the patterns of climate variability described in this report.
Has the PDO entered a warm phase?
It's quite possible that the PDO has entered a warm phase, though it's too early to say for sure. Here again is a chart showing the PDO and ENSO with GISTemp, click to enlarge it:
From the WUWT comments
Most WUWT comments showed that WUWT readers are fake sceptics. They took Eric's article as if it was an accurate depiction, which it wasn't. There were only a few people who noticed that Eric chose to mislead WUWT readers.
September 15, 2015 at 9:25 am
I am surprised that the Met Office did not read the memo from NOAA that the Pause in global warming is non-existent. Talk about a confused lot they seem to be.
September 15, 2015 at 10:01 am
Wait a minute, the headline to this that sprang up on Yahoo! stated that the Met Office had predicted the end of the hiatus…
September 15, 2015 at 10:38 am
Jokes are easy, but the take-away is good. The Pause exists. The Pause may well continue. This is a mainstream outfit obviously, and they are saying things that are highly inconvenient for the warmist crowd.
September 15, 2015 at 2:39 pm
– Headed up with a graph that has nothing to do with the report.
– The header link is to an article in an IT news-sheet. The link to the original 20-page paper is included only in the footer.
– The first and last of the 3 quotations are taken from page 11. There was a paragraph between them, but this has been removed and replaced by a different paragraph from a different section, on page 9.
It’s unclear to me why the quotations have been manipulated in this way. I assume that replacing the middle paragraph, which contained numerous literature references, had the benefit of giving the impression that this report (with its 4 pages of detailed international references) was merely a rambling PR job, rather than the very serious and balanced overview that it actually was.
Matt G thinks that the PDO warm phase is only going to last two years, which in effect means that he thinks the PDO is still in its cool phase (which may be the case). Although I don't know why he says that this El Nino "puts some of the ideas previously about the PDO into the bin":
September 15, 2015 at 4:10 pm
The most interesting part is if the current strong El Nino will cause a step up in global temperature after the immediate La Nina? (like the 1997/98 El Nino)
I don’t know, but sooner or later these strong El Nino’s will have a cooling affect after, once the accumulated energy has been released larger than the net intake. It’s been a long time coming since 1997/98 and after this event we should learn a lot from it. This strong El Nino also puts some of the ideas previously about the PDO into the bin. Usually during a long term negative PDO period you get weak El Nino’s, but we are in a short term positive PDO at the moment.
SAMURAI thinks it's going to get colder, and gets the length and timing of the oscillations cycles wrong (they are of no fixed length). He thinks the opposite to :
September 15, 2015 at 4:46 pm
The 30-yr PDO cool cycle already started in 2008, and the 30-yr AMO cool cycle will start around 2020. Moreover, the sun is entering a very weak phase, which may evolve into another Grand Solar Minimum…
There is a growing probability global temps may actually FALL 1C by 2100 should a GSM event occur, which would entirely wipeout the 0.85C of warming recovery experience since the end of the Little Ice Age in 1850….
The tiny amount of CO2 warming will actually mitigate some of the negative effects of a GSM, so ironically, manmade CO2 induced warming is a good thing. Moreover, the increased crop yields and forest growth will help offset the negative impacts of shorter growing seasons should a GSM occur.
Oh, the irony…. it cuts like a knife…
References and further reading
Big Changes Underway in the Climate System? UK Met Office, September 2015 - pdf here
Knight, Jeff R., Robert J. Allan, Chris K. Folland, Michael Vellinga, and Michael E. Mann. "A signature of persistent natural thermohaline circulation cycles in observed climate." Geophysical Research Letters 32, no. 20 (2005). doi:10.1029/2005GL024233 (open access)
Folland, Chris K., Andrew W. Colman, Doug M. Smith, Olivier Boucher, David E. Parker, and Jean‐Paul Vernier. "High predictive skill of global surface temperature a year ahead." Geophysical Research Letters 40, no. 4 (2013): 761-767. doi:10.1002/grl.50169 (open access)
From the HotWhopper archives
- Global Warming and the Pacific: Kevin Trenberth's Perspective - August 2015
- A short pause: Bob Tisdale thinks climate models are weather forecasts of the Northern Hemisphere - February 2015 - on the Atlantic Multidecadal Oscillation
- Bob Tisdale goes AMO-ing to a big chill - not! - May 2015 - also on the AMO