Leading Paleoclimatologist: Prepare for the Next Ice Age

[nzucker]

Except you specifically said .2-.3C was the standard of climatologists. Nice try though.

Which it isn't. Numerous studies in the last 5 years peg the equilibrium sensitivity and transient climate response lower than the IPCC mean of 3C. And the IPCC mean was around .18C/decade at the start of the 21st century.

I said "most climatologists and modeling agencies." Hadley is a modeling agency that supports the higher numbers. Hansen is a climatologist who supports the higher numbers. The poll is of climatologists even though it's being reported/interpreted by the popular media, and 200 of them seem to be leaning higher. IPCC is at .18C/decade which is close to .2C, a good estimation. Not sure why you're making such a big deal of this as the .2C-.3C range includes both more conservative estimates such as IPCC 2007 and more aggressive estimates such as Hadley 2010. Sure there are numbers below and above...there's plenty of studies that find the climate sensitivity to be less, and I'm sure some folks like Viner at Hadley believe it to be more. But .2-.3C is a very acceptable range.

Also, we are past the start of the 20th century by 11 years so the climate sensitivity for this decade on IPCC is higher than .18C.

Of course, the word "standard" can include media and science, but in this case I was referring to scientists and their feelings about decadal/century warming rates. Again, you are just trying to obscure the issue, which is that the Earth is not warming as fast as expected, by erroneously discrediting the higher end of the decadal range I used as being "extremist," even though Hadley Center is not considered an extremist organization in anyone's book.

[LakeEffectKing]

Maybe in the media it is downplayed but an understanding that the 11-yr solar cycle amplifies and depresses the warming has been understood for a while in the scientific literature.

So in your estimation, how much (in terms of temperature) can we attribute solar influences (current minimum) to the current "leveling" in the last decade? And to that point, how much (again in terms of temperature) can we attribute the warming in the last half of the past century to solar influences? Your recent comment about how "it's not surprising" is......well surprising, considering the considerable dearth of credit the experts give the sun relative to previous warmings....

[BethesdaWX]

And plenty of other respectable sources continue to disagree.

And even more agree...all who remove tree rings agree, tree rings suck for temperature.

Admit you were wrong regarding your statement, and I'll let it die.

[BethesdaWX]

No it has not, we are on the lower edge of IPCC confidence intervals, which is not surprising given the solar minimum.

To think this is only Intracycle cooling! Imagine what an extended minimum would do,we'd be back in a LIA in 150 years if we see 50-70 years of Maunder-like activity.

You're contradicting yourself. You agree with the IPCC, that says "Solar has minimal effect", yet PUNY intracycle cooling is here to affect the trend?

[tacoman25]

And .1C/decade is a good estimate of the lower IPCC models. If you're going to state that .3C/decade "is the expectation" you need to specify who, because it certainly is not the general expectation of scientists or the IPCC. Saying .3C/decade is the expectation is just as disingenuous as me claiming that .1C/decade is the expectation and IPCC models are verify perfectly correct.

Isn't the IPCC mean by 2020 like .23C/decade? Therefore, over the next 10-20 years, it's very fair to say the general expectation is .2-.3C/decade.

[tacoman25]

All I was making was a very simple straightforward correction to the claim that .2-.3C/decade is the "standard" expectation of climatologists.

What turned it into a big deal is your refusal to accept this very simple no big deal correction. The IPCC mean is .18C/decade.

Dude...that was for the 2000s. Nzucker was talking about where we would be IN 10 YEARS.

[WeatherRusty]

If we end up with no more forcing than a doubling of CO2 since pre-industrial times by 2060 then by 2090:

If equilibrium climate sensitivity equals:

2C = 0.16C per decade trend

3C= 0.24C per decade trend

4C= 0.32C per decade trend

[BethesdaWX]

If we end up with no more forcing than a doubling of CO2 since pre-industrial times by 2060 then by 2090:

If equilibrium climate sensitivity equals:

2C = 0.16C per decade trend

3C= 0.24C per decade trend

4C= 0.32C per decade trend

Doubling without feedbacks = 1C warming

Feedbacks = Mystery. In order for AGW to work, the climate needs to be full of positive feedbacks, not negative. About 90% of feedbacks are "assumed to be" based on correlations to Warming, when much of that "warming" may be a result of climactic forcings such as Cloud Cover. Its only Assumed that Cloud Cover is a Positive feedback.

We know 10/BE concentrations have correlated to warming in the pat, and that would have to be through GCC. So, if GCR's are really driving cloud cover...then AGW is probably comlpetely unmeasurable.

[tacoman25]

If we end up with no more forcing than a doubling of CO2 since pre-industrial times by 2060 then by 2090:

If equilibrium climate sensitivity equals:

2C = 0.16C per decade trend

3C= 0.24C per decade trend

4C= 0.32C per decade trend

By my math, these would be the numbers for 2060.

1C = .2C/decade

2C = .4C/decade

3C = .6C/decade

[BethesdaWX]

Dude...that was for the 2000s. Nzucker was talking about where we would be IN 10 YEARS.

The Cooling trend since 2002 is pretty damning considering the supposed trend to near +0.2C/decade.

What could causing more than -0.2C/decade cooling, when CO2 forcing is supposed to be overwhelming everything?

PDO was positive, but cooling. AMO was warming, IOD was warming, Global SST's were flat. Only thing that would have significant global impact would be either a) Sun, clouds, c) Both

But still, a cooling PDO would be met by a warming AMO & IOD, so that may cancel out?

[skierinvermont]

I said "most climatologists and modeling agencies." Hadley is a modeling agency that supports the higher numbers. Hansen is a climatologist who supports the higher numbers. The poll is of climatologists even though it's being reported/interpreted by the popular media, and 200 of them seem to be leaning higher. IPCC is at .18C/decade which is close to .2C, a good estimation. Not sure why you're making such a big deal of this as the .2C-.3C range includes both more conservative estimates such as IPCC 2007 and more aggressive estimates such as Hadley 2010. Sure there are numbers below and above...there's plenty of studies that find the climate sensitivity to be less, and I'm sure some folks like Viner at Hadley believe it to be more. But .2-.3C is a very acceptable range.

Also, we are past the start of the 20th century by 11 years so the climate sensitivity for this decade on IPCC is higher than .18C.

Of course, the word "standard" can include media and science, but in this case I was referring to scientists and their feelings about decadal/century warming rates. Again, you are just trying to obscure the issue, which is that the Earth is not warming as fast as expected, by erroneously discrediting the higher end of the decadal range I used as being "extremist," even though Hadley Center is not considered an extremist organization in anyone's book.

I'm not making a big deal, I am making a straightforward correction. The mean estimate of climatologists and modelling agencies is more like .15-.22C/decade, not .2-.3C/decade. I understand that you were ballparking, and I am making it more specific and accurate. It is not a big deal so there is no need to be so defensive.

Numerous climatologists and agencies have published climate sensitivities and transient climate responses lower than the IPCC mean estimates over the last 5 years.

[tacoman25]

I'm not making a big deal, I am making a straightforward correction. The mean estimate of climatologists and modelling agencies is more like .15-.22C/decade, not .2-.3C/decade.

Not by 2020 or 2021. You and Zucker both seem to have overlooked that point....he originally said 10 years from now.

[WeatherRusty]

So in your estimation, how much (in terms of temperature) can we attribute solar influences (current minimum) to the current "leveling" in the last decade? And to that point, how much (again in terms of temperature) can we attribute the warming in the last half of the past century to solar influences? Your recent comment about how "it's not surprising" is......well surprising, considering the considerable dearth of credit the experts give the sun relative to previous warmings....

Question 1) 0.1C peak to trough

Question 2) Very close to 0.0C. ~0.1C prior to 1970

[BethesdaWX]

As was stated, the 2000's were supposed to see a +0.18C/decade trend. Instead, we've seen a cooling trend since 2002 to this date, so something is removing 0.2C/decade of heat from the atmosphere.

Answer: Negative feedbacks in the Climate system. Nautral drivers are supposed to be overwhelmed by CO2, but apparently, this is not the case.

[skierinvermont]

Dude...that was for the 2000s. Nzucker was talking about where we would be IN 10 YEARS.

It's still not .2-.3C.. more like .15-.25

[tacoman25]

I'm not making a big deal, I am making a straightforward correction. The mean estimate of climatologists and modelling agencies is more like .15-.22C/decade, not .2-.3C/decade. I understand that you were ballparking, and I am making it more specific and accurate. It is not a big deal so there is no need to be so defensive.

Numerous climatologists and agencies have published climate sensitivities and transient climate responses lower than the IPCC mean estimates over the last 5 years.

And this is an interesting point that many seem to overlook. Despite numerous claims of rock solid science and consensus, the range in expected warming remains HUGE. Anywhere from 1C to 5C over the next 75-100 years? This proves there is a lot more uncertainty at play here than some let on.

[tacoman25]

It's still not .2-.3C.. more like .15-.25

I'm almost positive that was the expectation for the 2000s (after all, look at the decadal trends the previous couple decades). Maybe things have been revised since those numbers?

[skierinvermont]

As was stated, the 2000's were supposed to see a +0.18C/decade trend. Instead, we've seen a cooling trend since 2002 to this date, so something is removing 0.2C/decade of heat from the atmosphere.

Answer: Negative feedbacks in the Climate system. Nautral drivers are supposed to be overwhelmed by CO2, but apparently, this is not the case.

The +.18C/decade is the theoretical underlying trend due to CO2. It doesn't include perturbation to this trend due to ENSO or the solar cycle.

We can correct for ENSO using statistical techniques and when we do we find the 2000s had an ENSO corrected trend of ~.1C/decade (.12C/decade GISS, 08C/decade UAH).

Correcting for the solar cycle (we started the decade in a maximum ended in a minimum) removes most or all of the remaining discrepancy.

We had an extremely ENSO-negative and TSI-negative decade.

[BethesdaWX]

It's still not .2-.3C.. more like .15-.25

IPCC says "higher levels of warming cannot be ruled out", so technically it could.

point is, who gives s sh*t on 0.05C? You love starting arguments.

[skierinvermont]

I'm almost positive that was the expectation for the 2000s (after all, look at the decadal trends the previous couple decades). Maybe things have been revised since those numbers?

It really doesn't change much from decade to decade, there is very slow acceleration, especially early in the 21st century. I think the 2000s were ~.18C/decade.

[BethesdaWX]

The +.18C/decade is the theoretical underlying trend due to CO2. It doesn't include perturbation to this trend due to ENSO or the solar cycle.

We can correct for ENSO using statistical techniques and when we do we find the 2000s had an ENSO corrected trend of ~.1C/decade (.12C/decade GISS, 08C/decade UAH).

Correcting for the solar cycle (we started the decade in a maximum ended in a minimum) removes most or all of the remaining discrepancy.

You need to take out more than ENSO dude! The effects of Cloud Cover (GCC), GLAAM in locations of HLB & strength, Global SST.........The BASIS of the ENSO events, the Strength of the PDO....ALL will have effects that will alter the trendline.

You need to take all those out, which is why we cannot remove ENSO.

Unless you know how to adjust for those impacts (IPCC says they do not understand clouds, HLB, and most of the feedbacks in the climate system).

So you must be running a new world order!

[skierinvermont]

IPCC says "higher levels of warming cannot be ruled out", so technically it could.

point is, who gives s sh*t on 0.05C? You love starting arguments.

It's not an argument.. it's a straightforward simple correction. What causes an argument is when Zucker insists .2-.3C is actually representative of the typical climatologists perspective and claims the revisions have been towards the higher end over the last 5 years.

Which is just wrong.. most of the revisions the last 5 years have been to exclude the higher climate sensitivities.. I can give you half a dozen recent papers arguing against the higher climate sensitivities and/or transient climate responses.

[skierinvermont]

You need to take out more than ENSO dude! The effects of Cloud Cover (GCC), GLAAM in locations of HLB & strength, Global SST.........The BASIS of the ENSO events, the Strength of the PDO....ALL will have effects.

You need to take all those out, which is why we cannot remove ENSO!

ENSO, TSI, and volcanoes have by far the largest short-term effects in perturbing temperature. Removing those 3 variables gives us a much better estimate of the underlying trend. When we remove them, we find an underlying trend near to the expected .18C/decade in the 2000s.

[WeatherRusty]

And this is an interesting point that many seem to overlook. Despite numerous claims of rock solid science and consensus, the range in expected warming remains HUGE. Anywhere from 1C to 5C over the next 75-100 years? This proves there is a lot more uncertainty at play here than some let on.

The range of 2C - 4.5C is since pre-industrial times for whenever CO2 has doubled plus 2 or 3 decades to reach equilibrium (no remaining TOA imbalance), not the next 75-100 years. The uncertainty range given is the state of the science. It is that very acknowledged uncertainty which is most troubling, because above 2C (0.8C experienced already) we have big problems, and over 3C the world is a very different place.

[BethesdaWX]

ENSO, TSI, and volcanoes have by far the largest short-term effects in perturbing temperature. Removing those 3 variables gives us a much better estimate of the underlying trend. When we remove them, we find an underlying trend near to the expected .18C/decade in the 2000s.

Get your head out of your ass dude

The effects of Cloud Cover (GCC), GLAAM in locations of HLB & strength, Global SST.........The BASIS of the ENSO events, the Strength of the PDO....ALL will have significant effects that will alter the trendline.

All of those together will make or break a trend, thus we cannot remove.

[tacoman25]

The +.18C/decade is the theoretical underlying trend due to CO2. It doesn't include perturbation to this trend due to ENSO or the solar cycle.

We can correct for ENSO using statistical techniques and when we do we find the 2000s had an ENSO corrected trend of ~.1C/decade (.12C/decade GISS, 08C/decade UAH).

Correcting for the solar cycle (we started the decade in a maximum ended in a minimum) removes most or all of the remaining discrepancy.

We had an extremely ENSO-negative and TSI-negative decade.

Except you quoted the 1998-2010 trends...which are not extremely ENSO negative. Remember, 1999-2001 was a multi-year Nina. You are thinking of the trend since 2002, which is more ENSO negative.

[BethesdaWX]

We had an extremely ENSO-negative and TSI-negative decade.

The 2010 El Nino spike changes the entire picture.

[tacoman25]

The range of 2C - 4.5C is since pre-industrial times for whenever CO2 has doubled plus 2 or 3 decades to reach equilibrium (no remaining TOA imbalance), not the next 75-100 years. The uncertainty range given is the state of the science. It is that very acknowledged uncertainty which is most troubling, because above 2C (0.8C experienced already) we have big problems, and over 3C the world is a very different place.

Read the conversation and what skiier and zucker have said. There are "climate authorities" out there forecasting anything from 1C to 5C+ for the next 75-100 years. Hadley, considered one of the leading authorities, has gone on record as saying positive feedbacks could easily lead to 4-5C of warming before this century ends! While there are others out there forecasting below IPCC estimates, as low as 1C over the next 75 years.

[tacoman25]

The range of 2C - 4.5C is since pre-industrial times for whenever CO2 has doubled plus 2 or 3 decades to reach equilibrium (no remaining TOA imbalance), not the next 75-100 years. The uncertainty range given is the state of the science. It is that very acknowledged uncertainty which is most troubling, because above 2C (0.8C experienced already) we have big problems, and over 3C the world is a very different place.

http://climateprogress.org/2008/12/21/hadley-study-warns-of-catastrophic-5%c2%b0c-warming-by-2100-on-current-emissions-path/

Is the Hadley Center unaware of proper CO2 forcing? In 2008, they forecasted anywhere from 2.1C-7.1C rise in temperatures by 2100, depending on emissions between now and 2050.

[skierinvermont]

Recent papers on climate sensitivity and transient climate response:

Climate sensitivity:

Assigns the most likely climate sensitivity of only 1.6C/doubling, much below the IPCC: http://journals.amet...1175/JCLI3611.1

Argues against higher climate sensitivities and assigns a best guess of 2.9C slightly lower than the IPCC:http://www.nature.co...ature04679.html

Argues against highest climate sensitivities: http://www.nature.co...ature04679.html

Assigns a mean climate sensitivity of 2.8C, slightly lower than the IPCC: http://journals.amet...1175/JCLI3611.1

There has been little change in the best estimate of climate sensitivity: http://www.nature.co...bs/ngeo337.html

Argues against the higher climate sensitivities: http://www.springerl...p5t35mq27p3q24/

Argues against the higher climate sensitivities: http://citeseerx.ist...p=rep1&type=pdf

Uses a climate sensitivity lower than the IPCC: http://books.google....esponse&f=false

Transient Climate Response:

Argues for a lower transient climate response: http://www.agu.org/j...7GL032904.shtml

Argues for a transient climate response similar to the IPCC: http://homepages.see...Forster2008.pdf