New Study: No "hiatus" in AGW

[Cheeznado]

http://abcnews.go.com/Technology/wireStory/fed-data-shows-stopping-slowing-global-warming-31530995

[LocoAko]

Full paper: http://www.sciencemag.org/content/early/2015/06/03/science.aaa5632.full?sid=eb05f3e2-485f-420d-bc4c-a4cd367ad80c

 

PDF: http://www.sciencemag.org/content/early/2015/06/03/science.aaa5632.full.pdf?sid=eb05f3e2-485f-420d-bc4c-a4cd367ad80c

[StudentOfClimatology]

Interesting analysis, but rather unconvincing, especially their ISTI/ERSST3 merge in the face of better data like OISST or HADSST3 that have been thoroughly vetted? Why go through the trouble trying to rely on homogenizing bouy records to ship intake measurements when the ship intake data wasn't designed to measure climate in the first place due to frequent contamination? How do you determine which compartment to homogenize? That's very sketchy science and the final product will be full of spatial uncertainty.

If you ask me, this paper is analogous to a denier paper using ISCCP cloud cover data to claim that the warming is natural.

[stadiumwave]

The subject bias in climate science is down right ridiculous anymore.

And then we wonder why skeptic and non skeptics alike question data gathering at times. This is true denial!!

[Ginx snewx]

goal post change anyone?

 

http://mashable.com/2015/06/04/global-warming-hiatus-study/?utm_cid=hp-hh-pri

 

Lisa Goddard, director of the International Research Institute for Climate and Society (IRI) at Columbia University, told Mashable that the study does not support the conclusion that global warming didn't slow down for a relatively short time period.

"It is clear that Karl et al. have put a lot of careful work into updating these global products," Goddard said in an email.

 

"

"However, they go too far when they conclude that there was no decadal-scale slowdown in the rate of warming globally.

This argument seems to rely on choosing the right period — such as including the recent record-breaking 2014.

[AvantHiatus]

 

goal post change anyone?

 

http://mashable.com/2015/06/04/global-warming-hiatus-study/?utm_cid=hp-hh-pri

 

Lisa Goddard, director of the International Research Institute for Climate and Society (IRI) at Columbia University, told Mashable that the study does not support the conclusion that global warming didn't slow down for a relatively short time period.

"It is clear that Karl et al. have put a lot of careful work into updating these global products," Goddard said in an email.

 

"

"However, they go too far when they conclude that there was no decadal-scale slowdown in the rate of warming globally.

This argument seems to rely on choosing the right period — such as including the recent record-breaking 2014.

 

If your hiatus theory gets messed up by annual averages then you know it's not really relevant in the grand outcome of AGW.

[ORH_wxman]

If your hiatus theory gets messed up by annual averages then you know it's not really relevant in the grand outcome of AGW.

I haven't read the paper through fully yet but the irony of the SST augmentation that they use is that it reduces the warming trend overall from the late 19th century despite increasing the trend during the hiatus years.

[stadiumwave]

Great response by Dr. Judith Curry to this "new creation" by NOAA:

 

 

"The greatest changes in the new NOAA surface temperature analysis is to the ocean temperatures since 1998.  This seems rather ironic, since this is the period where there is the greatest coverage of data with the highest quality of measurements – satellites don’t show a warming trend.  Nevertheless, the NOAA team finds a substantial increase in the ocean surface temperature anomaly trend since 1998.

 

In my opinion, the gold standard dataset for global ocean surface temperatures is the UK dataset, HadSST3.  A review of the uncertainties is given in this paper by John Kennedy http://www.metoffice.gov.uk/hadobs/hadsst3/uncertainty.html.  Note, the UK group has dealt with the same issues raised by the NOAA team.  I personally see no reason to the use the NOAA ERSST dataset, I do not see any evidence that the NOAA group has done anywhere near as careful a job as the UK group in processing the ocean temperatures.

 

I am also unconvinced by NOAA’s gap filling in the Arctic, and in my opinion this introduces substantial error into their analysis.  I addressed the issue of gap filling in the Arctic in this recent publication:  Curry JA, 2014:  Climate science:  Uncertain temperature trends. Nature Geoscience, 7, 83-84.

Relevant text:

 

Gap filling in the Arctic is complicated by the presence of land, open water and temporally varying sea ice extent, because each surface type has a distinctly different amplitude and phasing of the annual cycle of surface temperature. Notably, the surface temperature of sea ice remains flat during the sea ice melt period roughly between June and September, whereas land surface warming peaks around July 1. Hence using land temperatures to infer ocean or sea ice temperatures can incur significant biases.

 

With regards to uncertainty, in their ‘warmest year’ announcement last January, NOAA cited an error margin in the global average surface temperature anomaly of 0.09^oC. The adjustments to the global average surface temperature anomaly is within the error margin, but the large magnitude of the adjustments further support a larger error margin.  But they now cite a substantially greater trend for the period 1998-2014, that is now statistically greater than zero at the 90% confidence level. 

 

My bottom line assessment is this.  I think that uncertainties in global surface temperature anomalies is substantially understated.  The surface temperature data sets that I have confidence in are the UK group and also Berkeley Earth.  This short paper in Science is not adequate to explain and explore the very large changes that have been made to the NOAA data set.   The global surface temperature datasets are clearly a moving target.  So while I’m sure this latest analysis from NOAA will be regarded as politically useful for the Obama administration, I don’t regard it as a particularly useful contribution to our scientific understanding of what is going on."

 

http://judithcurry.com/2015/06/04/has-noaa-busted-the-pause-in-global-warming/#more-18991

[chubbs]

I haven't read the paper through fully yet but the irony of the SST augmentation that they use is that it reduces the warming trend overall from the late 19th century despite increasing the trend during the hiatus years.

Yes the headline only tells part of the story. This is a case where government scientists have adjusted the data to reduce overall warming.

[donsutherland1]

Full paper: http://www.sciencemag.org/content/early/2015/06/03/science.aaa5632.full?sid=eb05f3e2-485f-420d-bc4c-a4cd367ad80c

 

PDF: http://www.sciencemag.org/content/early/2015/06/03/science.aaa5632.full.pdf?sid=eb05f3e2-485f-420d-bc4c-a4cd367ad80c

Interesting paper. Even as a thorough and detailed review of the data and corrections would require a period of time, some immediately sought to dismiss the paper. From The New York Times:

 

The Cato Institute, a libertarian think tank in Washington that is critical of climate science, issued a statement condemning the changes and questioning the agency’s methodology. “The main claim by the authors that they have uncovered a significant recent warming trend is dubious,” said the statement, attributed to three contrarian climate scientists: Richard S. Lindzen, Patrick J. Michaels and Paul C. Knappenberger.

 

http://www.nytimes.com/2015/06/05/science/noaa-research-presents-evidence-against-a-global-warming-hiatus.html?_r=0

 

When the scientific method is applied properly, review of the data is thorough. Findings one might not like require even greater caution to avoid one's conclusions being tainted by one's subjective biases. Given the complexity of the technical details (http://www.sciencemag.org/content/suppl/2015/06/03/science.aaa5632.DC1/Karl-SM.pdf) and cross-references to various other methodologies it's highly unlikely that an adequate review of the paper could have been completed just hours after it was released. 

 

Indeed, The New York Times article added:

 

At the same time, senior climate scientists at other agencies were in no hurry to embrace NOAA’s specific adjustments. Several of them said it would take months of discussion in the scientific community to understand the data corrections and come to a consensus about whether to adopt them broadly.

 

IMO, a near immediate rejection of the findings strongly indicates that those seeking to reject the paper failed to make the kind of meaningful effort required to understand the changes, much less comment on the merits of the paper in an informed fashion. If, in fact, it were that simple, serious climate scientists would not be suggesting that "months of discussion" might be required to assess the paper and underlying corrections.

 

A far better approach for those who may be skeptical of the paper's findings would have entailed stating that the existing temperature record appears to strongly support a "pause." Then, they could have noted that until the paper and its underlying methodology are carefully reviewed, it would be premature to suggest whether or not the paper's conclusions are robust.

[stadiumwave]

Interesting paper. Even as a thorough and detailed review of the data and corrections would require a period of time, some immediately sought to dismiss the paper. From The New York Times:

 

The Cato Institute, a libertarian think tank in Washington that is critical of climate science, issued a statement condemning the changes and questioning the agency’s methodology. “The main claim by the authors that they have uncovered a significant recent warming trend is dubious,” said the statement, attributed to three contrarian climate scientists: Richard S. Lindzen, Patrick J. Michaels and Paul C. Knappenberger.

 

http://www.nytimes.com/2015/06/05/science/noaa-research-presents-evidence-against-a-global-warming-hiatus.html?_r=0

 

When the scientific method is applied properly, review of the data is thorough. Findings one might not like require even greater caution to avoid one's conclusions being tainted by one's subjective biases. Given the complexity of the technical details (http://www.sciencemag.org/content/suppl/2015/06/03/science.aaa5632.DC1/Karl-SM.pdf) and cross-references to various other methodologies it's highly unlikely that an adequate review of the paper could have been completed just hours after it was released. 

 

Indeed, The New York Times article added:

 

At the same time, senior climate scientists at other agencies were in no hurry to embrace NOAA’s specific adjustments. Several of them said it would take months of discussion in the scientific community to understand the data corrections and come to a consensus about whether to adopt them broadly.

 

IMO, a near immediate rejection of the findings strongly indicates that those seeking to reject the paper failed to make the kind of meaningful effort required to understand the changes, much less comment on the merits of the paper in an informed fashion. If, in fact, it were that simple, serious climate scientists would not be suggesting that "months of discussion" might be required to assess the paper and underlying corrections.

 

 

Don....read what Dr. Curry stated.  I can't believe any objective person, skeptic or non-skeptic alike, cannot see immediately what's going on.  The "haitus", which is real, has been a real thorn for many reasons. 

 

#1 Producing lower confidence in our climate model predictions.

 

#2 Bringing into question the premise that climate sensitivity is extremely high...& thus rethinking "attribution" of the warming since 1950

 

#3 Failed predictions by fearmongers

 

#4 Ammunition for ignorant deniers

 

Just to name a few.  We all know the hiatus does not really mean anything in relation to the absolute truth of humans contributing to global warming. So, conveniently rewriting history to erase the hiatus is huge in public perception.

 

If climate science is really going to advance objectivity is a must.  Subjectivity has to die, as well as a desire to "be right" if climate science is to move forward.

[donsutherland1]

Don....read what Dr. Curry stated.  I can't believe any objective person, skeptic or non-skeptic alike, cannot see immediately what's going on.  The "haitus", which is real, has been a real thorn for many reasons. 

 

#1 Producing lower confidence in our climate model predictions.

 

#2 Bringing into question the premise that climate sensitivity is extremely high...& thus rethinking "attribution" of the warming since 1950

 

#3 Failed predictions by fearmongers

 

#4 Ammunition for ignorant deniers

 

Just to name a few.  We all know the hiatus does not really mean anything in relation to the absolute truth of humans contributing to global warming. So, conveniently rewriting history to erase the hiatus is huge in public perception.

 

If climate science is really going to advance objectivity is a must.  Subjectivity has to die, as well as a desire to "be right" if climate science is to move forward.

Personally, it's probably a little premature to accept the paper's conclusion that there may have been no hiatus whatsoever without a careful review of the paper, methodology, and data. I'll wait until some of the other major science organizations have vetted it, as I'm not a climate scientist with the requisite expertise.

 

It is plausible that a pause at the surface could have occurred without any impact on the larger issue of ongoing climate change e.g., the heat was accumulating below the sea surface (where OHC has been rising). A broader measure that ties together OHC, sea and land surface temperatures, and lower tropospheric readings, might well have shown steady warming. ENSO may well explain the pause in the major surface datasets, as the natural mechanism for bringing the OHC to the surface had been lacking in recent years due to the general absence of El Niño events. But we'll see what the later reviews of the paper have to say.

 

As the hiatus is a prominent issue, the paper will receive a lot of scrutiny. So, once there's a scientific consensus, I have confidence that it will be fairly robust.

 

Judith Curry had a thoughtful response.

 

P.S. It should be noted that with 2014's record and a possible record by a much larger margin this year, the hiatus may have ended.

[FloridaJohn]

Here's RealClimate's take on the new paper. Some useful quotes:

 

"This kind of update happens all the time as datasets expand through data-recovery efforts and increasing digitization, and as biases in the raw measurements are better understood."

 

"The first thing to remember is that an estimate of how much warmer one year is than another in the global mean is just that, an estimate. We do not have direct measurements of the global mean anomaly, rather we have a large database of raw measurements at individual locations over a long period of time, but with an uneven spatial distribution, many missing data points, and a large number of non-climatic biases varying in time and space. To convert that into a useful time-varying global mean needs a statistical model, good understanding of the data problems and enough redundancy to characterise the uncertainties."

 

"The sum total of the improvements discussed in the Science paper are actually small. There is some variation around the 1940s because of the ‘bucket’ corrections, and a slight increase in the trend in the recent decade: "

 

"The ‘selling point’ of the paper is that with the updates to data and corrections, the trend over the recent decade or so is now significantly positive. This is true, but in many ways irrelevant. This is because there are two very distinct questions that are jumbled together in many discussions of the ‘hiatus': the first is whether there is any evidence of a change in the long-term underlying trend, and the second is how to attribute short-term variations."

 

"The harrumphing from the usual quarters has already started. The Cato Institute sent out a pre-rebbutal even before the paper was published, replete with a litany of poorly argued points and illogical non-sequitors. From the more excitable elements, one can expect a chorus of claims that raw data is being inappropriately manipulated. The fact that the corrections for non-climatic effects reduce the trend will not be mentioned. Nor will there be any actual alternative analysis demonstrating that alternative methods to dealing with known and accepted biases give a substantially different answer (because they don’t)."

 

"Part of the problem here is simply semantic. What do people even mean by a ‘hiatus’, ‘pause’ or ‘slowdown’? As discussed above, if by ‘hiatus’ or ‘pause’ people mean a change to the long-term trends, then the evidence for this has always been weak. If people use ‘slowdown’ to simply point to a short-term linear trend that is lower than the long-term trend, then this is still there in the early part of the last decade and is likely related to an interdecadal period (through at least 2012) of more La Niña-like conditions and stronger trade winds in the Pacific, with greater burial of heat beneath the ocean surface."

[FloridaJohn]

Interesting analysis, but rather unconvincing, especially their ISTI/ERSST3 merge in the face of better data like OISST or HADSST3 that have been thoroughly vetted? Why go through the trouble trying to rely on homogenizing bouy records to ship intake measurements when the ship intake data wasn't designed to measure climate in the first place due to frequent contamination? How do you determine which compartment to homogenize? That's very sketchy science and the final product will be full of spatial uncertainty.

 

I look forward to reading your paper about how it should have been done.

[StudentOfClimatology]

I just finished reading the paper..I'm now convinced that it's garbage..I'm sure ORH_Wxman et al will agree. The methodology used to obtain the result is quite strange. They rely mostly on buoy data in the ERSST3 domain, which they then homogenize w/ ship intake data and merge with ISTI land surface to extend the data poleward, when they have prestigious SST datasets like HADSST3 and OISST3 readily available to homogenize subsequent extrapolations.

The choice to ignore the two best SST datasets in existence was the deal breaker for me.

[donsutherland1]

Here's RealClimate's take on the new paper. Some useful quotes:

 

"This kind of update happens all the time as datasets expand through data-recovery efforts and increasing digitization, and as biases in the raw measurements are better understood."

 

"The first thing to remember is that an estimate of how much warmer one year is than another in the global mean is just that, an estimate. We do not have direct measurements of the global mean anomaly, rather we have a large database of raw measurements at individual locations over a long period of time, but with an uneven spatial distribution, many missing data points, and a large number of non-climatic biases varying in time and space. To convert that into a useful time-varying global mean needs a statistical model, good understanding of the data problems and enough redundancy to characterise the uncertainties."

 

"The sum total of the improvements discussed in the Science paper are actually small. There is some variation around the 1940s because of the ‘bucket’ corrections, and a slight increase in the trend in the recent decade: "

 

"The ‘selling point’ of the paper is that with the updates to data and corrections, the trend over the recent decade or so is now significantly positive. This is true, but in many ways irrelevant. This is because there are two very distinct questions that are jumbled together in many discussions of the ‘hiatus': the first is whether there is any evidence of a change in the long-term underlying trend, and the second is how to attribute short-term variations."

 

"The harrumphing from the usual quarters has already started. The Cato Institute sent out a pre-rebbutal even before the paper was published, replete with a litany of poorly argued points and illogical non-sequitors. From the more excitable elements, one can expect a chorus of claims that raw data is being inappropriately manipulated. The fact that the corrections for non-climatic effects reduce the trend will not be mentioned. Nor will there be any actual alternative analysis demonstrating that alternative methods to dealing with known and accepted biases give a substantially different answer (because they don’t)."

 

"Part of the problem here is simply semantic. What do people even mean by a ‘hiatus’, ‘pause’ or ‘slowdown’? As discussed above, if by ‘hiatus’ or ‘pause’ people mean a change to the long-term trends, then the evidence for this has always been weak. If people use ‘slowdown’ to simply point to a short-term linear trend that is lower than the long-term trend, then this is still there in the early part of the last decade and is likely related to an interdecadal period (through at least 2012) of more La Niña-like conditions and stronger trade winds in the Pacific, with greater burial of heat beneath the ocean surface."

Thanks for this info. I suspect a key question concerns whether or not the paper's major conclusions would change were any of the other major datasets substituted. Certainly, any improvement in any data is a constructive development.

[nflwxman]

The amount of scrutiny the hiatus gets on "both" sides is

perplexing. This paper makes an interesting case for

the past decade, but the large scale changed in the early 20th century is pretty eye opening. Personally, I

think papers that stastically isolate all of

the natural variables that affect surface temperature more than adequately determine the cause of the slowdown.

People have used the hiatus to come to really premature assumptions about TCR and ECS, unfortunately.

[StudentOfClimatology]

The amount of scrutiny the hiatus gets on "both" sides is

perplexing. This paper makes an interesting case for

the past decade, but the large scale changed in the early 20th century is pretty eye opening. Personally, I

think papers that stastically isolate all of

the natural variables that affect surface temperature more than adequately determine the cause of the slowdown.

People have used the hiatus to come to really premature assumptions about TCR and ECS, unfortunately.

Agree 100% with this.

[The_Global_Warmer]

Bring back the hiatus

[ORH_wxman]

Yes the headline only tells part of the story. This is a case where government scientists have adjusted the data to reduce overall warming.

 

 

Yep....this is another reason why I always scoff at the obsession over hundreths of a degree in annual temp talk...the post hoc adjustments are often more than magnitude of the differences to begin with.

 

The new ERSSTv4 actually warmed the early period by quite a bit...and particularly the period in the late 19th century. This cuts the instrumental warming rate by over 10% despite the hiatus disappearing...but yet everyone is focused on the past 12-14 years.

 

If you didn't read any headlines about the hiatus, the first thing that probably stands out in the animation to most observers is how much the early period warmed:

 

 

 

 

 

 

 

 

 

 

 

 

 

So many of the responses on the blogosphere are typical fast responses with a predetermined mindset.

 

 

 

I'm not sure how robust these changes will stand up to scrutiny in the coming year and I haven't read the paper yet, so I won't make any judgements as to the validity of the changes.

[stadiumwave]

Personally, it's probably a little premature to accept the paper's conclusion that there may have been no hiatus whatsoever without a careful review of the paper, methodology, and data. I'll wait until some of the other major science organizations have vetted it, as I'm not a climate scientist with the requisite expertise.

 

It is plausible that a pause at the surface could have occurred without any impact on the larger issue of ongoing climate change e.g., the heat was accumulating below the sea surface (where OHC has been rising). A broader measure that ties together OHC, sea and land surface temperatures, and lower tropospheric readings, might well have shown steady warming. ENSO may well explain the pause in the major surface datasets, as the natural mechanism for bringing the OHC to the surface had been lacking in recent years due to the general absence of El Niño events. But we'll see what the later reviews of the paper have to say.

 

As the hiatus is a prominent issue, the paper will receive a lot of scrutiny. So, once there's a scientific consensus, I have confidence that it will be fairly robust.

 

Judith Curry had a thoughtful response.

 

P.S. It should be noted that with 2014's record and a possible record by a much larger margin this year, the hiatus may have ended.

 

 

 

An El Nino event will only produce a brief spike in global temps & back down we go with more than likely a strong Nina event afterwards. What happens after that is what will determine whether the hiatus is over.  Smart money is not.  PDO looks to be headed back down to negative territory which is expected.  Cooler anomalies are starting to surface around the west coast.  AMO is headed to negative territory.  The smart money says hiatus will not end until the next long-term PDO phase similar to what happened in 1978-1998.  The next jump will be greater one would think than 1978-1998 period.  If not then really serious questions should be asked about our current understanding of the climate system.

[stadiumwave]

Yep....this is another reason why I always scoff at the obsession over hundreths of a degree in annual temp talk...the post hoc adjustments are often more than magnitude of the differences to begin with.

 

The new ERSSTv4 actually warmed the early period by quite a bit...and particularly the period in the late 19th century. This cuts the instrumental warming rate by over 10% despite the hiatus disappearing...but yet everyone is focused on the past 12-14 years.

 

If you didn't read any headlines about the hiatus, the first thing that probably stands out in the animation to most observers is how much the early period warmed:

 

 

 

 

 

 

 

 

 

 

 

 

 

So many of the responses on the blogosphere are typical fast responses with a predetermined mindset.

 

 

 

I'm not sure how robust these changes will stand up to scrutiny in the coming year and I haven't read the paper yet, so I won't make any judgements as to the validity of the changes.

 

 

The downward adjustments from 1945-1970's is questionable.

 

I mean heck....what a moving target.  The more adjustments to the record...substantial ones at that...the more clueless we look.  Good grief!!  And if we can't even get the last 200 years right before that should truly be considered a shot in the dark.

[nflwxman]

An El Nino event will only produce a brief spike in global temps & back down we go with more than likely a strong Nina event afterwards. What happens after that is what will determine whether the hiatus is over. Smart money is not. PDO looks to be headed back down to negative territory which is expected. Cooler anomalies are starting to surface around the west coast. AMO is headed to negative territory. The smart money says hiatus will not end until the next long-term PDO phase similar to what happened in 1978-1998. The next jump will be greater one would think than 1978-1998 period. If not then really serious questions should be asked about our current understanding of the climate system.

If you think global temperatures ever go back to 2000-2010 levels again, you aren't paying attention. Of

course a La Niña will drop temperatures, but La Niña years continue to get warmer with AGW.  Look at the graph that TGW showed above, you can't have that much heat building in the 0-700m range without some of the imbalance making it to the sfc temperature record.

The smart bet is to assume continued average warming at about 0.16-.2C per decade.  My personal thought is that natural variability will lead to a much steeper climb in temperatures between 2015-2024 than 0.2 C/decade. 

[stadiumwave]

If you think global temperatures ever go back to 2000-2010 levels again, you aren't paying attention. Of

course a La Niña will drop temperatures, but La Niña years continue to get warmer with AGW.

The smart bet is to assume continued average warming at about 0.16-.2C per decade.

Well...they already are per RSS & UAH. Tell me why I should trust NOAA/NCDC/NASA after this bull of a paper when trends on GISS, RSS, UAH, & Hadcrut have always been very close even during NINO events. Why such a departure 2014 & this year? If RSS & UAH do not catchup then something is just wrong.

[StudentOfClimatology]

Well...they already are per RSS & UAH. Tell me why I should trust NOAA/NCDC/NASA after this bull of a paper when trends on GISS, RSS, UAH, & Hadcrut have always been very close even during NINO events. Why such a departure 2014 & this year? If RSS & UAH do not catchup then something is just wrong.

GISS is the NASA dataset. It also happens to show more warming recently than NCDC, while HADCRUT4, RSS, and UAH show less.

The question of whether or not the "hiatus" is over cannot be answered right now, despite all the talking points. I could see us returning to 2008-2013 levels in 2016/2017, or stepping up much like we did after the 1998 Niño. We'll have to wait and see.

[nflwxman]

UAH and RSS don't measure the same thing as GISS/HADCrut4, NOAA, JMA, BEST ect.

 

Since 2000:

 

GISS warmed 0.145C

 

HADCRUT4 warmed 0.125C

 

NOAA warmed 0.132C

 

Not exactly a huge difference given the short time frame.

[StudentOfClimatology]

Here's a closer look at the five datasets. All this is pretty semantical when looking at the higher resolution depictions. Obviously, we'll have to wait and see regarding the continuation or cessation of the hiatus. Way too early to tell.

Right now we're still in the 2001-2013 "hiatus" standard deviation, on aggregation, statistically speaking. GISS and NCDC show slight warming since 2001, HADCRUT4, UAH, and RSS show slight cooling since 2001.

[nflwxman]

No cooling on Hadcrut4 since 2001.  Still warming FWIW.

 

We are not going back to the "hiatus."  It's really silly thinking otherwise.  By 2016 it will be 8 years after 2008 and unless the PDO and ENSO go LOWER than the hiatus years, they should be a fair bit warmer than 2008-2012, per additional forcing on the climate.  This is all barring a major volcanic eruption.  Simple statistics show that type of deviation from the trend line would be like a 3 sigma event.

 

The "stadiumwave" theory with Judith Curry is really out of the mainstream when she suggest the hiatus can last until 2030.  It quite simply ain't going to happen.  Even with a Mauder Minimum.

[StudentOfClimatology]

I could easily envision us returning to 2008-2013 levels for awhile, or I could envision this being another step change upwards. On 10-25yr scales, forcings can destructively interfere, so making declarations now is kind of silly. There's more that goes into short term climate change than ENSO, TSI, and volcanism.

We'll see what the climate system decides to do over the next several years. There isn't much that would surprise me, at this point.

[nflwxman]

I could easily envision us returning to 2008-2013 levels for awhile, or I could envision this being another step change upwards. On 10-25yr scales, forcings can destructively interfere, so making declarations now is kind of silly.

There's a lot more that goes into short term climate change than ENSO, TSI, and volcanism.

 

Nothing that can bring us back to 2008-2013 levels except ENSO and Volcanism.  And ENSO would really have to tank.  Like big time (think Super Nina). I'd encourage you to read the Church paper from Nature that shows hiatus periods become extremely unlikely by 2030 assuming BAU.

 

http://www.nature.com/articles/nclimate2513.epdf?referrer_access_token=NMvH_xHJTvCIc2CRWXNSQtRgN0jAjWel9jnR3ZoTv0OO9zeaQM0SsZ36aVR-KegKF_L2Vn8Ed-qCHOFxjrQ8LFNq2kxIXMoZgPzvYj0xt2IHgRdSSMtOcMgKOLNFR-_-Nsx26_7DGqCH1pFw-cu8PjKEV7Ws0_sOCyfe4FeoPjrYR99xEHljSuXvrrEu2ds_rJITL_JWsUMxgFCY8LTxPA%3D%3D&tracking_referrer=www.abc.net.au