Natural radiative forcings

[Geckko]

Originally Posted by mhaze

I am fairly certain that this is an actual case of 5+ years hindcasting and 15- years futurecasting, but do you have a page refence to verify?

They should have at least got their hindcasting right.

The climate projections are contained in Chapter 10 of AR4, which can be downloaded here:

http://ipcc-wg1.ucar.edu/wg1/wg1-report.html

It is very clear that the projections (e.g. "0.4 degrees warming expected over the the next two decades"; "0.2 degrees of warming already committed over the next two decades") relate to the model ensemble runs that were for 2000-2100. This is repeatedly mentioned through the chapter, for example here on page 753 where they introduce the approach taken to produce the projections:



Or, this is a nice one, showing graphically the process, of running the models from 2000, based on information up to that point (hence the incorporate the effect of the naturally warmer 1998 that might lead to slower temp increases in the short term because you are moving from a higher base):



What I am trying to do for myself is square the circle and this requires to compare information on an appropriate yardstick. The yardstick to assess the projection is the period over which they were made which was from 2000.

[Geckko]

Originally Posted by CapelDodger

"For the next two decades a warming of about 0.2°C per decade is projected for a range of SRES emissions scenarios", as a statement made in 2007, presumably refers to the next two decades - 2008-2027.

Let's get back together in 2027 and see how that works out. I doubt they'll be far out.

I think you are right; that I can assess what happens over the 20 years from 2007. Equally I could do 20 years from 2010 or 2020.

But what I read is information about the IPCC projections from 2000 (although published in 2007) and now 8 years (40% of a 20 year projection) of observable outcome, plus some peer reviewed updated projections that cover the balance of that 2000-2020 period (which might end up being refuted, but presently stand in the literature).

That is useful information now - hence my initial quandry as outlined in the OP.

[mhaze]

Originally Posted by Geckko

The climate projections are contained in Chapter 10 of AR4, which can be downloaded here:

http://ipcc-wg1.ucar.edu/wg1/wg1-report.html

It is very clear that the projections (e.g. "0.4 degrees warming expected over the the next two decades"; "0.2 degrees of warming already committed over the next two decades") relate to the model ensemble runs that were for 2000-2100. This is repeatedly mentioned through the chapter, for example here on page 753 where they introduce the approach taken to produce the projections:



Or, this is a nice one, showing graphically the process, of running the models from 2000, based on information up to that point (hence the incorporate the effect of the naturally warmer 1998 that might lead to slower temp increases in the short term because you are moving from a higher base):



What I am trying to do for myself is square the circle and this requires to compare information on an appropriate yardstick. The yardstick to assess the projection is the period over which they were made which was from 2000.

I thought that was where you were at, but wasn't sure. I've read that chapter many times.

For starters, there is this concept often expressed of "Warming yet in the pipeline" from the past accumulation of CO2 from the industrialized nations output which is supposed to keep warming the atmosphere even if emissions were drastically cut immediately.

No evidence of "warming yet in the pipeline" is displayed from 2000 on, though.

[lomiller]

Originally Posted by mhaze

google <--- rahmstorf climate

answers this, nothing more needs be said.

As I said, if you don't want to specify which of these supposed criticisms you think are valid or come from valid sources I can live with that.

Originally Posted by mhaze

http://www.internationalskeptics.com...134dddac9a.png

We "are doing better" at cooling than under the "draconian emissions" cuts scenario and we have had basically no emissions cuts.

As you have been informed of repeatedly, actual emissions fall just under “Hanson B”, the light blue line on the graph so those projections are bang on with reality.

[lomiller]

Originally Posted by Geckko

What I am trying to do for myself is square the circle and this requires to compare information on an appropriate yardstick. The yardstick to assess the projection is the period over which they were made which was from 2000.

Perhaps this will help, it’s a plot of the individual realizations that made up the IPCC ensemble prediction. Because climate is chaotic, a model will give a different result each time, so this is all the runs of all the models used. Note how wide the range is in the individual models, and how many have low and even legitimate cooling periods of nearly 2 decades.

Actual climate is similarly just one realization, so the range of possibilities should be as great as what you see in the model realizations.

[CapelDodger]

Originally Posted by David Rodale

BTW Capeldodger, in your haste to repeat ad nauseum (and erroneously) referring to Lindzen's "iris effect" as ridiculous, please note that satellite observations support his hypothesis. References available upon request, but then observations aren't really in the AGW Manifesto are they?

Consider the references requested.

[CapelDodger]

Originally Posted by Geckko

I think you are right; that I can assess what happens over the 20 years from 2007. Equally I could do 20 years from 2010 or 2020.

But what I read is information about the IPCC projections from 2000 (although published in 2007) and now 8 years (40% of a 20 year projection) of observable outcome, plus some peer reviewed updated projections that cover the balance of that 2000-2020 period (which might end up being refuted, but presently stand in the literature).

That is useful information now - hence my initial quandry as outlined in the OP.

Presumably "For the next two decades a warming of about 0.2 per decade is projected" comes from the Summary for Policymakers, page 12. I see no reason to think that "the next two decades" doesn't mean precisely that - the next two decades, 2008-2027. Which, after all, is what policymakers are going to be interested in. We're hardly a year into that yet, so we'll have to wait and see.

Which may well be what the policymakers do; they've done squat so far.

[CapelDodger]

Originally Posted by David Rodale

That should read:
If you’re content to leave it at your link to a blog vs my link to a an paper essay published printed in the magazine Science , I can live with that.

Science is not just "a magazine". It is a prestigious journal which publishes peer-reviewed papers.

Quote:

The AGW axiom:
1) Necessarily the climate models cannot be falsified.
2) If the climate models didn’t represent reality, they could be falsified.
3) Therefore the climate models represent reality.

Keep it up, you're doing your case no end of good.

Quote:

Do you know what parameterization (fudging) is?

I know what flailing around looks like, and I'm looking at it right there.

Quote:

Assessment of the reliability of climate predictions
based on comparisons with historical time series

From the abstract

Quote:

"Based on these analyses, we discuss the usefulness of climatic model future projections (with emphasis on precipitation) from a hydrological perspective, in relationship to a long-term uncertainty framework. "

Coming from the National Technical University of Athens, Faculty of Civil Engineering, Department of Water Resources and Environmental Engineering, that's hardly surprising. It doesn't say much about temperature modelling (and I doubt you'll convince Greeks that there's been cooling since 2000).

Quote:

On the credibility of climate predictions

Not sure about that one, the link gives me some stuff about my cookie settings, but from the quote you provide it concerns eight (count them, eight) stations, and also gets into precipitation.

Quote:

There are many others ...

I doubt that. Not just because you say so, but generally.

Quote:

but also recently which you have no doubt read in full.
Spencer, R.W., and W.D. Braswell, 2008: Feedback vs. Chaotic Radiative Forcing: “Smoking Gun” Evidence for an Insensitive Climate System?

Spencer again. The guy puts Don Quixote to shame.

Got anything relevant and credible?

Quote:

What is earth's climate sensitivity lomiller?

Speaking for myself, it's sensitive enough that the world's glaciers and Arctic ice are disappearing rapidly.

Quote:

Where is the missing hot spot?

What is this "hotspot" I keep hearing about? mhaze won't tell me, despite repeated requests.

Quote:

Where is the missing heat from Hansen's "smoking gun"?

What missing heat?

Quote:

I'll be patiently waiting for the AGW scripted answers, unsupported statements and more magazine essays. Or will we be treated to more news hype on "unprecedented" Arctic ice melt?

We'll be waiting for more of the same from you. I bet Spencer will be included.

The fact that you sing with a choir doesn't mean everyone does.

[Pipirr]

Originally Posted by CapelDodger

Science is not just "a magazine". It is a prestigious journal which publishes peer-reviewed papers.

Its an oddity, because a lot of people would describe it as 'the journal Science'. But the AAS do in fact call it Science Magazine, and the URL is sciencemag.com. Maybe science.com was already taken...

I have found that 'Science Magazine' is a damn sight easier to find than just 'Science' in library system searches. The curse of a very generic journal name.

I would have gone with 'Science Journal' myself.

[mhaze]

Originally Posted by Pipirr

Its an oddity, because a lot of people would describe it as 'the journal Science'. But the AAS do in fact call it Science Magazine, and the URL is sciencemag.com. Maybe science.com was already taken...

I have found that 'Science Magazine' is a damn sight easier to find than just 'Science' in library system searches. The curse of a very generic journal name.

I would have gone with 'Science Journal' myself.

You would probably have made less money with your product then, as the number of people who picked up a copy in Barnes and Noble would have gone down. That is, people pick up "a magazine" from the "magazine racks" and buy "a magazine". I gotta conclude that thing is "a magazine".

[Geckko]

Originally Posted by lomiller

Perhaps this will help, it’s a plot of the individual realizations that made up the IPCC ensemble prediction. Because climate is chaotic, a model will give a different result each time, so this is all the runs of all the models used. Note how wide the range is in the individual models, and how many have low and even legitimate cooling periods of nearly 2 decades.

Actual climate is similarly just one realization, so the range of possibilities should be as great as what you see in the model realizations.

That isn't much help actually.

Don't forget I have read the original (go to the link in the OP). They stress the use of ensembles rather than any single model run (presumably especially in the case where you have some observations and you are searching a large number of models to find one that fits the data - flawed statistics)

The WG1 report takes care to point out some of the following:

Quote:

Many of the figures in Chapter 10 are based on the mean and spread of the multi-model ensemble of comprehensive AOGCMs. The reason to focus on the multi-model mean is that averages across structurally different models empirically show better large-scale agreement with observations, because individual model biases tend to cancel (see Chapter 8). The expanded use of multi-model ensembles of projections of future climate change therefore provides higher quality and more quantitative climate change information compared to the TAR.

and

Quote:

The use of multi-model ensembles has been shown in other modelling applications to produce simulated climate features that are improved over single models alone (see discussion in Chapters 8 and 9).

[mhaze]

Originally Posted by Geckko

That isn't much help actually.

Don't forget I have read the original (go to the link in the OP). They stress the use of ensembles rather than any single model run (presumably especially in the case where you have some observations and you are searching a large number of models to find one that fits the data - flawed statistics)

The WG1 report takes care to point out some of the following:

Quote:
Many of the figures in Chapter 10 are based on the mean and spread of the multi-model ensemble of comprehensive AOGCMs. The reason to focus on the multi-model mean is that averages across structurally different models empirically show better large-scale agreement with observations, because individual model biases tend to cancel (see Chapter 8). The expanded use of multi-model ensembles of projections of future climate change therefore provides higher quality and more quantitative climate change information compared to the TAR.

and

Quote:
The use of multi-model ensembles has been shown in other modelling applications to produce simulated climate features that are improved over single models alone (see discussion in Chapters 8 and 9).

I fail to see any merit in a "mean" (multi-model mean) drawn from unlike sample populations, and error bounds from such a "mean" would seem to also suffer from a lack of meaning.

[CapelDodger]

Originally Posted by Pipirr

Its an oddity, because a lot of people would describe it as 'the journal Science'. But the AAS do in fact call it Science Magazine, and the URL is sciencemag.com. Maybe science.com was already taken...

I have found that 'Science Magazine' is a damn sight easier to find than just 'Science' in library system searches. The curse of a very generic journal name.

I would have gone with 'Science Journal' myself.

There's an in-house magazine element to Science ("This Week in Science", "News Focus", "Perspectives", book reviews, editorial, etc), it isn't just a dry-as-dust Journal. On the other hand, it's far from being "Hello!" magazine or whatever in-house newsletter Heritage Foundation or Discovery Institute members get. The stuff towards the back of Science has real meat in it.

The AAAS is just a club, but it's a prestigious club for good reason. The good reason being that it has standards, and the people involved in it take them very seriously.

[CapelDodger]

Originally Posted by Geckko

I am trying to make sense of recent developments on the climate change front. I start with the IPCC views on the sources of forcings shown in this graph.


http://www.realclimate.org/images/ipcc2007_radforc.jpg


Conclusion: Anthorpogenic dominate natural by a wide margin.

Naturally , the logical conculsion is drawn in the AR4 Summary for Policymakers in the interpretation of what was making temperatures rise over the last 50 years, as in this quote:


And they go on to make the logical projected statement as follows:





So I am happy that I understand from that::

• Natural forcings are theoretically too small to swamp anthropogenic forcings
• Over the last 50 years anthropogenic forcings have easily dominated natural forcings (as theory suggested)
• Over the next 20 years (2000-2020 in the context of AR4) the predictable natural forcings will not be enough to swamp anthropogenic forcings (even if the increase in anthropogenic forcings stopped completely in 2000)

But, here is the confusion. Standing in 2008 I have been seeing the following fairly recently:

1. Measured data showing no trend increase in temperatures for the last 10 years:
   
   http://wattsupwiththat.files.wordpre...ng?w=510&h=303
   
   
   
2. some recent peer review work citing "natural forces" as being likely to produce no further wraming for another 10 years - http://www.nature.com/nature/journal...ture06921.html
   

That leaves me a little confused.

1. We believe that anthropogenic forcings dominate natural forcings and have done so significantly in the past and had expected them to do so over the future, but
   
2. Over the most recent decade global average temperatures have not increased despite anthropogenic forcings continuing to rise, which some researchers suggest might be due to natural forcings that were deemed to be theoretically and observationally too insignificant to have any material affect in comparison.

I hope that isn't too confusing.

I must confess to being a little confused by this. Quite apart from who "we" refers to, "The next ten years" in a paper published in Nature you take to mean the next ten years from now, whereas "The next two decades" in the AR4 (2007) you take to mean the next two decades from 2000. Perhaps it would be clearer if you specified exactly what you mean by "we", in this context.

We (meaning all of us) have been able to observe the glacial retreat, Arctic sea-ice loss, and permafrost-melt since 2000, thanks to the internet, satellite pictures, and reports from intrepid people with cramponed boots on the ground (of whom Watts ain't one, by the way). And we'll be able to observe the next few years as well. I don't see hope winning out over unfeeling reality, however the numbers are manipulated. (Not that Watts trusts numbers anyway, without photographs to back them up.)

The next two-to-seven years will weed out most of the speculation. We're on a steep learning-curve, one way or other.

[lomiller]

Originally Posted by Geckko

That isn't much help actually.

Don't forget I have read the original (go to the link in the OP). They stress the use of ensembles rather than any single model run (presumably especially in the case where you have some observations and you are searching a large number of models to find one that fits the data - flawed statistics)

The WG1 report takes care to point out some of the following:



and

Ensembles improve the calculation of the trend, it does not remove natural variation from individual realizations. You are confusing the trend with the variation in the trend of one realization, the actual observed climate.

The earths climate is a chaotic system, so it will generally follow a trend but randomly be above/below that trend, sometimes for more then a decade. The range of values in the model runs show us the limits to that possible variation.

[mhaze]

Originally Posted by lomiller

Originally Posted by mhaze
The much criticized Ramsdorf 2007, which Megalon kept posting the comparative chart from.

Originally Posted by lomiller
Criticized by whom? You realize you can’t say something is “much criticized” based on your own criticism right?

Originally Posted by mhaze
google <--- rahmstorf climate
answers this, nothing more needs be said.

Originally Posted by lomiller
As I said, if you don't want to specify which of these supposed criticisms you think are valid or come from valid sources I can live with that.

Bwhahahaha!

Criticized by whom?

Self evident from a simple Google check, you should have done that first.

You realize you can’t say something is “much criticized” based on your own criticism right?

A made up yet irrelevant argument from one who didn't do any homework.

As I said, if you don't want to specify which of these supposed criticisms you think are valid or come from valid sources I can live with that.

As you didn't say. Your question was fully answered: Criticised by whom: Answer: Google ---> many.

Now you would change that goalposts and indicate you'd like more information. Why not just say it? If after studying the criticisms a bit you want to defend this paper go at it.

Oh wait - It wasn't even on the right IPCC report. Never mind.

[CapelDodger]

Originally Posted by mhaze

Bwhahahaha!

Criticized by whom?

Self evident from a simple Google check, you should have done that first.

So you've got nothing. Fair enough; nobody expected anything different.

[mhaze]

Originally Posted by CapelDodger

So you've got nothing. Fair enough; nobody expected anything different.

Since it is not on topic (proven) and since I have shown many such links, your derail attempt is silly. But I leave you with an amusing tidbit from one of the many criticisms:

quantitative and rational evaluation of reality has its limits in the case of the climatic hot head (Stefan Rahmstorf)

[Geckko]

Originally Posted by lomiller

Ensembles improve the calculation of the trend, it does not remove natural variation from individual realizations. You are confusing the trend with the variation in the trend of one realization, the actual observed climate.

The earths climate is a chaotic system, so it will generally follow a trend but randomly be above/below that trend, sometimes for more then a decade. The range of values in the model runs show us the limits to that possible variation.

Please stay on topic. I meant this to address some specific issues. There are lots of other threads for partisan nitpicking.

I am confusing nothing.

We have the IPCC projections.

We have some data.

We have some new peer review research.

If you have nothing to say in answer to my OP, please don't send this into an irrecoverable OT spin like so many other threads.

[CapelDodger]

Originally Posted by mhaze

Since it is not on topic (proven) and since I have shown many such links, your derail attempt is silly. But I leave you with an amusing tidbit from one of the many criticisms:

quantitative and rational evaluation of reality has its limits in the case of the climatic hot head (Stefan Rahmstorf)

So you've still got nothing. Fair enough; nobody excepted anything different.

[Dancing David]

Wow, congratulation! This seems to have the minimum of trolling response ever.

I am glad to see that some people still can't muster more that the Discovery Institute and Plasma Cosmology type arguments.

Geckko, I am confused, what specific point would you like to have discussed? Thanks.

[mhaze]

Originally Posted by Geckko

Please stay on topic. I meant this to address some specific issues. There are lots of other threads for partisan nitpicking.

I am confusing nothing.
We have the IPCC projections.
We have some data.
We have some new peer review research......

Comments by Dr. Scott Armstrong on Patrick Frank's article in Skeptic (2008, 14:1) titled “A climate of belief”:

Frank demonstrates that the IPCC grossly under-reports the cumulative uncertainty of the model forecasts. The figure below from Frank’s article shows that, when proper allowance is made for uncertainty about the effects of clouds and greenhouse gases, the nominal bounds of errors in the complex IPCC models’ forecasts of temperature change by 2100 are plus or minus 120°C. As a consequence, the IPCC projections contain no useful information. It would be foolish indeed to base public policy on forecasts from such models.

[Spud1k]

Originally Posted by Geckko

Please stay on topic. I meant this to address some specific issues. There are lots of other threads for partisan nitpicking.

I am confusing nothing.

We have the IPCC projections.

We have some data.

We have some new peer review research.

If you have nothing to say in answer to my OP, please don't send this into an irrecoverable OT spin like so many other threads.

The issue is that climate forcing works on time scales of longer than decades, so looking at the variability over the last few years doesn't really tell you anything about any natural vs anthropogenic radiative forcing. Thanks to the heat capacity and dynamics of the oceans you could be increasing the amount of overall heat within the earth system and yet the mean surface temperature could be constant or even decreasing within the time bracket of a few years (and vice versa for that matter).

Bottom line is that it is far too soon to say whether the predictions in the latest IPCC report were accurate or not.

[CapelDodger]

Originally Posted by Spud1k

The issue is that climate forcing works on time scales of longer than decades, so looking at the variability over the last few years doesn't really tell you anything about any natural vs anthropogenic radiative forcing. Thanks to the heat capacity and dynamics of the oceans you could be increasing the amount of overall heat within the earth system and yet the mean surface temperature could be constant or even decreasing within the time bracket of a few years (and vice versa for that matter).

Bottom line is that it is far too soon to say whether the predictions in the latest IPCC report were accurate or not.

The contrarian concentration on this current decade indicates, IMO, that we're into the end-game of the "controversy". In the next two-to-seven years we'll see global surface temperatures breach 1998, if only because we'll get a sustained El Nino during that period. 2005 matched 1998 without one. 2007 would have breached 1998 without the La Nina at the end (which, of course, stores up heat under the Western Pacific). I don't know how significant the amount of heat absorbed by the melting of Arctic sea-ice is, but it's not zero, and there's not much sea-ice left to absorb more.

When I see (as I have) contrarians make much of the difference between Jan 2008 and Jan 2007, I know I'm looking at a collapsing case.

[CapelDodger]

Originally Posted by lomiller

Ensembles improve the calculation of the trend, it does not remove natural variation from individual realizations. You are confusing the trend with the variation in the trend of one realization, the actual observed climate.

The earths climate is a chaotic system, so it will generally follow a trend but randomly be above/below that trend, sometimes for more then a decade. The range of values in the model runs show us the limits to that possible variation.

Well said.

[mhaze]

Originally Posted by CapelDodger

....In the next two-to-seven years we'll see global surface temperatures breach 1998, if only because we'll get a sustained El Nino during that period. 2005 matched 1998 without one. 2007 would have breached 1998 without the La Nina at the end (which, of course, stores up heat under the Western Pacific). I don't know how significant the amount of heat absorbed by the melting of Arctic sea-ice is, but it's not zero, and there's not much sea-ice left to absorb more.....

Since we are in the negative PDO phase and El Nino occurs in the positive PDO phase, you will not see your El Nino in your 7 year timeframe.

[CapelDodger]

Originally Posted by Geckko

Please stay on topic. I meant this to address some specific issues. There are lots of other threads for partisan nitpicking.

I am confusing nothing.

We have the IPCC projections.

We have some data.

We have some new peer review research.

If you have nothing to say in answer to my OP, please don't send this into an irrecoverable OT spin like so many other threads.

As I said in post #54, you have confused me. You have projections from the IPCC AR4 2007 for the next two decades, which you say means from 2000; you have a peer-reviewed paper in Nature referring to the next one decade, which you say means from 2008. That's in the OP.

Even if that made any obvious sense, lomiller has pointed out that the data from between 2000 and 2008 is too short to reveal anything about the climate trend.

If you could clear up the confusion it would be much appreciated.

[CapelDodger]

Originally Posted by mhaze

Since we are in the negative PDO phase and El Nino occurs in the positive PDO phase, you will not see your El Nino in your 7 year timeframe.

I've made my prediction, and now you've made yours. See you in two-to-seven years to settle up. If I'm wrong, I'll go hands-up like a true mensch.

[lomiller]

Originally Posted by Geckko

Please stay on topic. I meant this to address some specific issues. There are lots of other threads for partisan nitpicking.

If you are going to say the answer to your question is outside the topic I guess I can’t help you, nor is it likely that anyone else will either.

Originally Posted by Geckko

I am confusing nothing.

You most certainly are. The observed climate is just one realization of an infinite number of possibilities within a given range. Like an individual model run it’s a single realization. The IPCC isn’t attempting to predict the individual realization they are attempting to predict the range and mean of the possible realization. Just as with the models those individual realizations can have variation between them even on a scale of 10+ years.

As long as you do not understand the difference in behavior of the ensemble trend and individual realization, and trend for an individual realization you will never find an answer to the questions you are asking. The question I am now asking myself is if you are deliberately refusing to understand the distinction.

[mhaze]

Originally Posted by CapelDodger

I've made my prediction, and now you've made yours. See you in two-to-seven years to settle up. If I'm wrong, I'll go hands-up like a true mensch.

Well, I'm only stating some basic established science:

1. The PDO is about a 60 year cycle with a positive and negative section of about 30 years each.
2. The positive section of the PDO has El Nino, the negative has La Nina.
3. We are in a negative section (cooling).

Conclusion: There will be no El Nino in the next 2-7 years.

There are several "abouts" in 1, 2, and 3, granted; the exact start and stop of the negative phase we are in case only be guessed at; but you don't seem to be lined up with these basic facts....

So let me restate your premise:

AGW will overwhelm the (relatively weak) global cooling effect of PDO negative/La Nina within 2-7 years because AGW is far more powerful an effect. If not El Nino, then some other powerful manifestation of AGW will come forth and do its job.
within 2-7 years.

But the planet disagrees with you:

And here is our favorite graph that sums this century up quite nicely. Now look over at .... 2000+. See the big black line? See the error bounds? See the line past 2000 goes D-O-W-N?

[Spud1k]

Originally Posted by mhaze

Well, I'm only stating some basic established science:

1. The PDO is about a 60 year cycle with a positive and negative section of about 30 years each.
2. The positive section of the PDO has El Nino, the negative has La Nina.
3. We are in a negative section (cooling).

Conclusion: There will be no El Nino in the next 2-7 years.

I wouldn't call #2 'basic established science' myself, but hey.

Originally Posted by mhaze

And here is our favorite graph that sums this century up quite nicely. Now look over at .... 2000+. See the big black line? See the error bounds? See the line past 2000 goes D-O-W-N?

Is it just me, or do the two sets of oscillations in your two graphs not match up time-wise? The two troughs in the top graph occur around 1920 and 1960, which correspond to periods of warming and cooling respectively in your bottom graph, putting the two phenomena out of phase with each other. More generally, the top graph doesn't seem to follow anything resembling a nice sinusoid pattern, so how can you justify using it for the bottom graph or having any confidence in its predictions?

You'll forgive me for being sceptical of hand-waving approaches such as this when it comes to explaining the decadal variations in climate. A few years ago, your crowd were claiming that these oscillations could be explained in their entirety by solar activity, but that all turned out to be wishful thinking. What makes this any different?

[bobdroege7]

Originally Posted by mhaze

Well, I'm only stating some basic established science:

1. The PDO is about a 60 year cycle with a positive and negative section of about 30 years each.
2. The positive section of the PDO has El Nino, the negative has La Nina.
3. We are in a negative section (cooling).

Conclusion: There will be no El Nino in the next 2-7 years.

This site lists el nino and la nina years from 1950 to 2003

http://ggweather.com/enso/years.htm

Note the lack of 30 year periodicity.

You are confusing ENSO with PDO, therefore your conclusion of no El Nino in the next 2-7 years is bunk.

[fsol]

Atmoz has an interesting looking post up about the PDO today.

http://atmoz.org/blog/2008/08/03/on-...n-temperature/

His post before that on the PDO is also interesting.

http://atmoz.org/blog/2008/05/14/tim...o-nao-and-amo/

[mhaze]

Originally Posted by bobdroege7

Originally Posted by mhaze
Well, I'm only stating some basic established science:

1. The PDO is about a 60 year cycle with a positive and negative section of about 30 years each.
2. The positive section of the PDO has El Nino, the negative has La Nina.
3. We are in a negative section (cooling).

Conclusion: There will be no El Nino in the next 2-7 years.

Originally Posted by bobdroege7
This site lists el nino and la nina years from 1950 to 2003
http://ggweather.com/enso/years.htm
Note the lack of 30 year periodicity.

You are confusing ENSO with PDO, therefore your conclusion of no El Nino in the next 2-7 years is bunk.

Since PDO is calculated (in hindsight, some years of) from ENSO, how could that be?

Just one of many explanations of the relationship, this from worldcimatereport.com:

the state of El Niño Southern Oscillation (ENSO), the swing back and forth between the El Niño warm pools and La Niña cool pools, is strongly related to a much larger Pacific Decadal Oscillation (PDO) covering much of the North Pacific Ocean and impacting the entire Pacific Ocean. The phase of the PDO can not only change the probability of having El Niño or La Niña, but the phase of PDO also determines how strongly El Niño or La Niña will impact weather conditions from Australia to Florida. Once again, we learn that things are more complicated than they seem at first – any discussion about global warming, El Niño, and effects on regional climates must account for potential changes in PDO.

Joseph, R. and S. Nigam, 2006. ENSO evolution and teleconnections in IPCC’s twentieth-century climate simulations: Realistic representation? Journal of Climate, 19, 4360-4377.

[bobdroege7]

Originally Posted by mhaze

2. The positive section of the PDO has El Nino, the negative has La Nina.

I was just trying to point out that the statement above is just flat out wrong, and your world climate report article supports that.

from

http://www.worldclimatereport.com/in...about-el-nino/

Originally Posted by world climate report

The phase of the PDO can not only change the probability of having El Niño or La Niña, but the phase of PDO also determines how strongly El Niño or La Niña will impact weather conditions from Australia to Florida.

So your conclusion that there will be no El Nino in the next 2-7 years is not supported by your arguments

[mhaze]

Originally Posted by bobdroege7

I was just trying to point out that the statement above is just flat out wrong, and your world climate report article supports that. from
http://www.worldclimatereport.com/in...about-el-nino/

So your conclusion that there will be no El Nino in the next 2-7 years is not supported by your arguments

Yes, I should have said something like "El Ninos are mostly seen in the positive PDO phrase".

Originally Posted by fsol

Atmoz has an interesting looking post up about the PDO today.

http://atmoz.org/blog/2008/08/03/on-...n-temperature/

His post before that on the PDO is also interesting.

http://atmoz.org/blog/2008/05/14/tim...o-nao-and-amo/

Nice articles, but a bit confused. He seems to think someone does not believe PDO is a cycle and/or that he needs to caution people about detrending, etc. Perhaps there is such confusion, but if so he does not carry the argument to a logical conclusion by identifying specific abusers of the PDO in climate arguments and showing their errors. In fact, to the contrary: his conclusions should caution Warmers about making conclusions about their (very short) 30 year 1978+ timeframe which is all they have for satellite records:

It is important to be careful when making statements about long period oscillations in a time series that is short. When there are less than 2 full periods in the record, it is very difficult to say what the actual main period of the oscillation actually is.

When comparing two climate metrics, it is important to know their definition. It makes no sense to compare the temperature trend of the PDO to anything, since the PDO has no trend. If it is necessary to compare the PDO to the global temperatures, it is first necessary to detrend the temperatures or to calculate an adjusted PDO that includes the trend.