Welcome Guest! To enable all features please Login. New Registrations are disabled.

Notification

Icon
Error

71 Pages«<697071
Options
Go to last post Go to first unread
Offline John S2  
#1401 Posted : 05 August 2012 14:26:39(UTC)
John S2

Rank: Advanced Member

Joined: 06/04/2006(UTC)
Posts: 1,775
Location: West Yorks/East Lancs

This is a response to the following comment from Stephen Wilde in the Arctic Sea Ice thread:
'As for the suggestion that the globe is showing a 'robust' upward temperature trend, I find that laughable.'
I like this article which appeared on Skeptical Science on 01/05/12:
http://www.skepticalscie...nued-global-warming.html
Within the article is a chart showing trendlines of global temperatures for the 44 years starting in 1967. Individual years are categorised into three groups according to whether the average ENSO condition over 12 months was El Nino, neutral, or La Nina. The upward linear trend is similar for each group.
I would also mention research by Foster & Rahmstorf [2011] which concluded that there has been no recent slowdown or acceleration of global warming when short term noise [ENSO, volcanic eruptions] and solar variations [which are small] are removed from the signal.
Offline Solar Cycles  
#1402 Posted : 05 August 2012 15:02:38(UTC)
Solar Cycles

Rank: Advanced Member

Joined: 04/09/2008(UTC)
Posts: 18,483
Man
Location: Blackburn Lancs

Originally Posted by: John S2 Go to Quoted Post
This is a response to the following comment from Stephen Wilde in the Arctic Sea Ice thread:
'As for the suggestion that the globe is showing a 'robust' upward temperature trend, I find that laughable.'
I like this article which appeared on Skeptical Science on 01/05/12:
http://www.skepticalscience.com/john-nielsen-gammon-commentson-on-continued-global-warming.html
Within the article is a chart showing trendlines of global temperatures for the 44 years starting in 1967. Individual years are categorised into three groups according to whether the average ENSO condition over 12 months was El Nino, neutral, or La Nina. The upward linear trend is similar for each group.
I would also mention research by Foster & Rahmstorf [2011] which concluded that there has been no recent slowdown or acceleration of global warming when short term noise [ENSO, volcanic eruptions] and solar variations [which are small] are removed from the signal.
This is what YD and I have been saying John, that temps have remained static for the past fifteen years. It will be interesting to watch which signal will be the overriding one over the next few years, or whether temps remain static.
Offline Gandalf The White  
#1403 Posted : 05 August 2012 16:00:33(UTC)
Gandalf The White

Rank: Advanced Member

Joined: 12/04/2006(UTC)
Posts: 40,228
Man

Originally Posted by: Solar Cycles Go to Quoted Post
Originally Posted by: John S2 Go to Quoted Post
This is a response to the following comment from Stephen Wilde in the Arctic Sea Ice thread:
'As for the suggestion that the globe is showing a 'robust' upward temperature trend, I find that laughable.'
I like this article which appeared on Skeptical Science on 01/05/12:
http://www.skepticalscience.com/john-nielsen-gammon-commentson-on-continued-global-warming.html
Within the article is a chart showing trendlines of global temperatures for the 44 years starting in 1967. Individual years are categorised into three groups according to whether the average ENSO condition over 12 months was El Nino, neutral, or La Nina. The upward linear trend is similar for each group.
I would also mention research by Foster & Rahmstorf [2011] which concluded that there has been no recent slowdown or acceleration of global warming when short term noise [ENSO, volcanic eruptions] and solar variations [which are small] are removed from the signal.


This is what YD and I have been saying John, that temps have remained static for the past fifteen years. It will be interesting to watch which signal will be the overriding one over the next few years, or whether temps remain static.



I'm puzzled by this post, SC.   John makes it clear that there has been no slowdown (or acceleration) in global wamring when short term noise is excluded, yet you feel it appropriate to restate that temperatures have remained static for the past 15 years.


That ignores, of course, the deeply flawed logic (or attempted deception, depending on your motive) of using 1997/98 as your baseline.  You must have seen my repeated flagging of this point whenever Stephen tries the same trick.


 

Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E
Offline John Mason  
#1404 Posted : 05 August 2012 16:03:41(UTC)
John Mason

Rank: Advanced Member

Joined: 06/04/2006(UTC)
Posts: 3,447

Oh, they see what they want to see, GTW!

Offline Stephen Wilde  
#1405 Posted : 05 August 2012 17:17:24(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266

"Feedbacks in response to climate variations during the period 2000-2010 have been calculated using reanalysis meteorological fields and top-of-atmosphere flux measurements. Over this period, the climate was stabilized by a strongly negative temperature feedback"


http://journals.ametsoc....5/JCLI-D-11-00640.1?af=R

There might be room for differences about how the stabilisation was achieved but not as regards the stabilisation itself.

If one says that the stabilisation was achieved by La Ninas then it follows that the earlier warming was caused by El Ninos.

That begs the question as to why the late 20th century El Ninos were so strong.

The best explanation is reduced global cloudiness caused by more zonal jets allowing more sunlight into the oceans.

The problem for AGW theory is that the positive water vapour feedback is supposed to result in more clouds but that didn't happen.


Offline TomC  
#1406 Posted : 06 August 2012 10:11:47(UTC)
TomC

Rank: Advanced Member

Joined: 27/04/2006(UTC)
Posts: 11,024
Location: Glossop

A strongly negative temperature fedback arises from an El-Nino (warm ocean surface anomaly. you really need to read the paper carefully.

Offline Stephen Wilde  
#1407 Posted : 26 August 2012 18:10:27(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266


Then a strongly negative feedback arises from AGW warming too does it not ?

Both El NIno and CO2 add energy to the air and the system response is the same in both cases (a shift in the global air circulation) but the effect of human emissions of CO2 is infinitesimal compared to the effect of an El Nino.



Offline John Mason  
#1408 Posted : 26 August 2012 20:27:49(UTC)
John Mason

Rank: Advanced Member

Joined: 06/04/2006(UTC)
Posts: 3,447

In any given year, yes.
Offline Stephen Wilde  
#1409 Posted : 26 August 2012 21:11:16(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266

So what shift in air circulation would you expect from a doubling of CO2 as compared to the solar induced oceanic effect between MWP and LIA or LIA and today ?

Edited by user 27 August 2012 07:05:05(UTC)  | Reason: Not specified

Offline Stephen Wilde  
#1410 Posted : 27 August 2012 07:04:45(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266

John,

Have you noticed that you just accepted that the system response to warming of the air from El Nino events and warming in the air from more CO2 would be the same.

That is, negative.

Yet AGW theory relies upon a positive feedback from more CO2

If we applied the supposed positive feedback of CO2 to El Nino events then the increased water vapour in the air from the El Nino warmth (a GHG after all) would give even more water vapour in the air in an ever increasing feedback loop until a single El Nino event causes catastrophic consequences.

Doesn't happen though does it ?

What is supposed to be so different with regard to the warming of the air by CO2 ?

Edited by user 27 August 2012 07:07:00(UTC)  | Reason: Not specified

Offline TomC  
#1411 Posted : 27 August 2012 10:30:49(UTC)
TomC

Rank: Advanced Member

Joined: 27/04/2006(UTC)
Posts: 11,024
Location: Glossop

Originally Posted by: Stephen Wilde Go to Quoted Post


John,

Have you noticed that you just accepted that the system response to warming of the air from El Nino events and warming in the air from more CO2 would be the same.

That is, negative.

Yet AGW theory relies upon a positive feedback from more CO2

If we applied the supposed positive feedback of CO2 to El Nino events then the increased water vapour in the air from the El Nino warmth (a GHG after all) would give even more water vapour in the air in an ever increasing feedback loop until a single El Nino event causes catastrophic consequences.

Doesn't happen though does it ?

What is supposed to be so different with regard to the warming of the air by CO2 ?



El-Ninos last a few months to a year the water vapour feedback taskes decades as does CO2 induced warming as we see in the data. The transient response to ENSO is very different to the change in forcing produced by changing atmospheric composition or solar output. That was the big mistake Lindzen made in his Earth Iris paper.

Offline Stephen Wilde  
#1412 Posted : 27 August 2012 11:35:13(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266

Sorry Tom, that doesn't get you out of the problem.

The relative strengths of El Nino and La Nina change over that 1000 year cycle from MWP to LIA to date so we need to compare the scale of that process to the scale of any effect from human emissions.Over 500 years of increasingly strong El Nino events there would be plenty of time for a positive water vapour response to show up but it never did.

Focusing on individual ENSO events is misleading.

The system response to warming of the air by El Nino is negative and not positive at all timescales. There was no visible increase in global humidity during the late 20th century warming, in fact it seems to have reduced.

The response to AGW warming is just the same.

How far do you think the jets and climate zones shift as a result of more human emissions compared to the solar / ocean induced shifts over that 1000 year cycle ?

Not long ago ALL the shifting was being put down to AGW. That proposition is now obviously a dead duck.





Offline Gandalf The White  
#1413 Posted : 27 August 2012 11:42:19(UTC)
Gandalf The White

Rank: Advanced Member

Joined: 12/04/2006(UTC)
Posts: 40,228
Man

Originally Posted by: Stephen Wilde Go to Quoted Post


Not long ago ALL the shifting was being put down to AGW. That proposition is now obviously a dead duck.


All?  Do you have evidence for that assertion?


 


Originally Posted by: Stephen Wilde Go to Quoted Post


That proposition is now obviously a dead duck.


How so?  What evidence do you have?

Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E
Offline TomC  
#1414 Posted : 27 August 2012 11:55:03(UTC)
TomC

Rank: Advanced Member

Joined: 27/04/2006(UTC)
Posts: 11,024
Location: Glossop

Further ENSO events have no long term impact on global temperature they are just internal variability when an El-Nino or La-Nina ends the temperature returns to its pre-existing value in a few months.


On the subject of atmospheric water vapour it has increased (Stephen is confusing water vapour content and relative humidity)


eg


http://www.pnas.org/content/104/39/15248.abstract


Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m2 per decade since 1988. Results from current climate models indicate that water vapor increases of this magnitude cannot be explained by climate noise alone. In a formal detection and attribution analysis using the pooled results from 22 different climate models, the simulated “fingerprint” pattern of anthropogenically caused changes in water vapor is identifiable with high statistical confidence in the SSM/I data. Experiments in which forcing factors are varied individually suggest that this fingerprint “match” is primarily due to human-caused increases in greenhouse gases and not to solar forcing or recovery from the eruption of Mount Pinatubo. Our findings provide preliminary evidence of an emerging anthropogenic signal in the moisture content of earth's atmosphere.

Edited by user 27 August 2012 12:04:05(UTC)  | Reason: Not specified

Offline Stephen Wilde  
#1415 Posted : 27 August 2012 12:07:10(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266

"Further ENSO events have no long term impact on global temperature they are just internal variability when an El-Nino or La-Nina ends the temperature returns to its pre-existing value in a few months."


Focus on the longer term. Individual ENSO events are simply imposed on the longer term 1000 year cycle from MWP to LIA to date.

Over that period the relative strengths of El Nino and La Nina gradually shift under the effect of solar changes.


That is why one sees upward stepping from one PDO phase to the next when there is a background wasrming trend such as the recovery from the LIA.


Gsandalf asks:

"How so? What evidence do you have?"


CO2 continues to rise but the jets are no longer shifting poleward as evidenced by the current widely acepted change to greater jetstream meridionality.


Offline Stephen Wilde  
#1416 Posted : 27 August 2012 12:13:46(UTC)
Stephen Wilde

Rank: Advanced Member

Joined: 10/06/2008(UTC)
Posts: 3,266



http://www.stuff.co.nz/s...-warming-science-tackled

"The theory assumes no other major influence on temperature changed, so the effect of the CO2 must have been amplified threefold, presumably by changes in the atmosphere due to humidity and clouds.

There is no observational evidence for this amplification, but it is nonetheless built into all the models. Sceptics point out that if the extra humidity simply forms extra clouds, then there would be no amplification
"

Clouds have been increasing since around 2000.
Offline TomC  
#1417 Posted : 27 August 2012 12:25:41(UTC)
TomC

Rank: Advanced Member

Joined: 27/04/2006(UTC)
Posts: 11,024
Location: Glossop

Originally Posted by: Stephen Wilde Go to Quoted Post


http://www.stuff.co.nz/science/7400061/Global-warming-science-tackled

"The theory assumes no other major influence on temperature changed, so the effect of the CO2 must have been amplified threefold, presumably by changes in the atmosphere due to humidity and clouds.

There is no observational evidence for this amplification, but it is nonetheless built into all the models. Sceptics point out that if the extra humidity simply forms extra clouds, then there would be no amplification
"

Clouds have been increasing since around 2000.


There is direct evidence for it from increasing water vapour as I have linked above. You need to post evidence for increasing cloudiness since 2000. The sign of the cloud feedback is very sensitive to the type of cloud that increases. Remember , however, there is direct observed evidence for the increase in water vapour and the positive water vapour feedback. Still I am gald you now conceed , as does the article you link that doubling CO2 causes  a 1C warming alone. As the article says serious sceptics do indeed accept this point.

Edited by user 27 August 2012 12:30:11(UTC)  | Reason: Not specified

Offline TomC  
#1418 Posted : 27 August 2012 13:05:12(UTC)
TomC

Rank: Advanced Member

Joined: 27/04/2006(UTC)
Posts: 11,024
Location: Glossop

Originally Posted by: Stephen Wilde Go to Quoted Post


CO2 causes a 1C warming if all else remains equal but in fact there appears to be a negative system response.

The evidence on increased high and medium clouds plus reducing low clouds since 2000 combined with increasing global albedo as reported by the Earthshine project has already been supplied.

I'm going to take a break now.

I find you and John Mason reasonable to deal with even if your interpretations of the available evidence do not match mine.



An increase in high and medium level cloud would cause enhanced warming.

Offline Solar Cycles  
#1419 Posted : 27 August 2012 16:14:51(UTC)
Solar Cycles

Rank: Advanced Member

Joined: 04/09/2008(UTC)
Posts: 18,483
Man
Location: Blackburn Lancs

Originally Posted by: Stephen Wilde Go to Quoted Post
"Further ENSO events have no long term impact on global temperature they are just internal variability when an El-Nino or La-Nina ends the temperature returns to its pre-existing value in a few months."


Focus on the longer term. Individual ENSO events are simply imposed on the longer term 1000 year cycle from MWP to LIA to date.

Over that period the relative strengths of El Nino and La Nina gradually shift under the effect of solar changes.


That is why one sees upward stepping from one PDO phase to the next when there is a background wasrming trend such as the recovery from the LIA.


Gsandalf asks:

"How so? What evidence do you have?"


CO2 continues to rise but the jets are no longer shifting poleward as evidenced by the current widely acepted change to greater jetstream meridionality.


I think Stephen's response regarding how the jets no longer move poleward needs a response from Tom, as the theory states that the jets will continue to move polewards and remain in that position as long as CO2 levels remain at there present levels and higher.
Users browsing this topic
71 Pages«<697071
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

Code of conduct

× FORUM Settings Posting League USER PHOTOS Sky Eye Camera Sky Eye Live Sky Eye Gallery MODEL CHARTS Arome Arpege ECM ECM ENS GEM GEFS GFS HIRLAM Icon Met Office UM Fax CFS GFSP