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IPCC Report is Released


donsutherland1

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But CO2 forcing is a small overall. Cloud cover variations and water vapor changes in the upper troposphere which amplify or damp radiative forcing are not fully known. How can you say this? Remember CO2 is a weak GHG.  It only has effect at -50C which is associated with the 15 micron absorption band.  There is no observational evidence that the upper troposphere is warming very much at all. There is also a presentation that shows that the IR opacity of the Earth has changed little in the past 60 years despite increasing CO2. 

 

see  http://climateclash.com/ferenc-miskolczi-the-stable-stationary-value-of-the-earths-ir-optical-thickness/

 

Ah so you abandon your original argument and jump ship the hard-core denier favorite: CO2 is a weak GHG. 

 

If you actually think you have evidence that CO2 is a weak GHG, why bother entertaining us with the antics of other irrelevant arguments that in reality are all dependent on your initial (and false) assumption that CO2 is a weak GHG?

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You seem to have an overly simplistic view of the PDO/ENSO relationship. During a +PDO phase, the tendency is towards stronger +PDO, regardless of exact ENSO. During -PDO phase, vice versa. Which is why you'll find that between 1976-2005, even weak +ENSO years often produced significant +PDO....and since then, even weak -ENSO years produce major -PDO. Which was also the case from 1946-1975 during the last -PDO phase.

 

You really think the sudden flip to warming in the late 1970s had very little to do with the PDO phase flip? Or the lack of warming since the early/mid 2000s isn't related to the -PDO phase setting in again?

 

Too many coincidences if you ask me. The oceans are a huge factor in decadal/multi-decadal climate trends, and the PDO is the most powerful oceanic oscillation. 

 

I'm aware of this. But if you want to define the PDO, or at least the climactically significant portion of it as the residual of PDO-ENSO, then the PDO was still negative until the mid 1980s. And of course warming had started long before then.

 

So what's the climactically significant variable? How do you want to define the PDO "phase?" Is it the PDO value itself, or is it the PDO-ENSO residual?

 

Again you're dissecting it and trying to squeeze it into a box. In reality it's simple

 

1) The eyeball appearance of a correlation is dependent upon two coincidences a) the flip in PDO and temperature in 1945 and B) the flip in PDO and temperature in 1977. Two coincidences are hardly the basis of a strong statistical correlation nevermind causation.

 

2) This eyeball correlation is made artificially stronger by the flips in ENSO that occurred simultaneous to the PDO. These changes in ENSO surely do effect temperature, but the continued warming after 1983 is attributable neither to ENSO nor to the PDO. Without CO2, the jump in temperature 1977-1983 would have been unsustainable. 

 

3) All of this requires glossing over the continued warming after the PDO went neutral in 1998 and negative in 2008. Again if you want to say it was still positive 1998-2008, then you must also say it was still negative 1977-1983. And then you cannot attribute the warming 1977-1983 to the PDO.

 

You can't attribute both the warming 1977-1983 and the warming 1998-2008 to the PDO or ENSO. 

 

 

I'm not saying the PDO has no effect. It has a modest effect mostly through ENSO.

 

I'd say the PDO/ENSO had a .1C step warming effect 1975-1985 and a .1C step cooling effect 1998-2010. 

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Will, while it is a little rambling, it is a very good direct discussion of the two seperate issues:

 

1) Why has warming slowed?

 

2) Why has warming been slower than modeled?

 

 

They answer 1) very directly: the observed recent warming hiatus, defined as the reduction in GMST trend during 1998–2012 as compared to the trend during 1951–2012, is attributable in roughly equal measure to a cooling contribution from internal variability and a reduced trend in external forcing (expert judgment, medium confidence).

 

They answer 2) as well: There is medium confidence that the GMST trend difference between models and observations during 1998–2012 is

to a substantial degree caused by internal variability, with possible contributions from forcing error and some CMIP5 models overestimating the response to increasing greenhouse-gas forcing. 

 

The reduced trend in forcing from #1 is due to volcanic aerosols and the weak solar cycle. 

 

In #2 the overestimated response to ghg forcing is a reference to the fact that the CMIP5 model mean may overestimate climate sensitivity by 10%. There is no mean bias between CMIP5 models and AR5 best estimate forcing. So the models forcing probably is not off by much. But they seem unsure of exactly how CMIP5 models are handling aerosols, so there may be some forcing bias there. 

 

There's still the persistent fact that they have low confidence in aerosol data (AOD - aerosol optical depth) and so while there is no mean bias vs their 'best estimate' of forcing, their forcing estimate has low confidence because of the lack of confidence in AOD trends.

 

In short, aerosols may still be partially responsible for both the warming hiatus and the model discrepancy.  Internal variability may be responsible for both as well. The hiatus (#1) is also partially caused by a slowdown in forcing increase but this cannot explain #2. Models have reasonable agreement with the best estimate for forcing, but there could still be some bias. 

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I'm aware of this. But if you want to define the PDO, or at least the climactically significant portion of it as the residual of PDO-ENSO, then the PDO was still negative until the mid 1980s. And of course warming had started long before then.

 

So what's the climactically significant variable? How do you want to define the PDO "phase?" Is it the PDO value itself, or is it the PDO-ENSO residual?

 

Again you're dissecting it and trying to squeeze it into a box. In reality it's simple

 

1) The eyeball appearance of a correlation is dependent upon two coincidences a) the flip in PDO and temperature in 1945 and B) the flip in PDO and temperature in 1977. Two coincidences are hardly the basis of a strong statistical correlation nevermind causation.

 

2) This eyeball correlation is made artificially stronger by the flips in ENSO that occurred simultaneous to the PDO. These changes in ENSO surely do effect temperature, but the continued warming after 1983 is attributable neither to ENSO nor to the PDO. Without CO2, the jump in temperature 1977-1983 would have been unsustainable. 

 

3) All of this requires glossing over the continued warming after the PDO went neutral in 1998 and negative in 2008. Again if you want to say it was still positive 1998-2008, then you must also say it was still negative 1977-1983. And then you cannot attribute the warming 1977-1983 to the PDO.

 

You can't attribute both the warming 1977-1983 and the warming 1998-2008 to the PDO or ENSO. 

 

 

I'm not saying the PDO has no effect. It has a modest effect mostly through ENSO.

 

I'd say the PDO/ENSO had a .1C step warming effect 1975-1985 and a .1C step cooling effect 1998-2010. 

 

1. There is a definite causation. You know the significant effect the oceans have on temperature trends. And you are forgetting the third and fourth "coincidences" - rising temps during the +PDO phase preceding the mid 1940s, the lack of warming over the past decade as the -PDO phase has returned.

 

2. You are again confusing the short term effects ENSO has has on global temps, and the longer/multi-decadal effects of oceanic phases. The PDO phase certainly affects ENSO tendencies overall.

 

3. Are you even looking at the actual PDO index, in relation to what was going on ENSO-wise? 1976-83 was certainly a +ENSO period, but the PDO flip was clear starting in 1976-77, when a relatively minor Nino produced significant +PDO. Overall, 1976-83 was both a +ENSO and +PDO period punctuated by a record strong Nino at the end.

 

In addition, as I have gone over previously, the evidence that the PDO phase truly flipped in the 2006-08 period also lies in the dominant patterns since then.

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I have always contended that the primary effect of the PDO was simply the short term effect of ENSO. All else equal, an El Nino in a +PDO would have a similar global temperature to an El Nino in a -PDO. 

 

The rising temperatures until the 1940s are easily explained by the large solar forcing increase, the positive volcanic forcing, and the increased occurrence of El Ninos. 

 

in addition, if ocean oscillations were as powerful as you contend, then they would show up in modifying the earth's energy budget. By artificially constraining surface temperature increase, -PDOs would broaden the energetic imbalance of the earth, and lead to rapid OHC increase.

 

Instead, previous and current -PDO periods were simultaneous with periods of little (first episode) and slow (present episode) OHC increase which suggests it was little more than coincidence and that the cooling during the previous episode, and slower warming during the present episode, were externally forced.

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Ah so you abandon your original argument and jump ship the hard-core denier favorite: CO2 is a weak GHG. 

 

If you actually think you have evidence that CO2 is a weak GHG, why bother entertaining us with the antics of other irrelevant arguments that in reality are all dependent on your initial (and false) assumption that CO2 is a weak GHG?

It is pretty much well accepted that CO2 is a weak GHG. It, alone, cannot do much to the climate  system other than around 1.2C at best without feedbacks upon doubling. This is within the range of normal variability and is of no significant concern. It is the feedbacks that is the main question in all this and I can tell you there is a ton of uncertainty in the feedbacks(you should know this). That is where I stand. Without significant positive feedbacks, there isn't much concern. Its all conjecture based on model guidance just like weather forecasters looking at uncertain model guidance 7 to 10 days or beyond from now. We see this all this  time in the field of meteorology...using models to make forecasts. When there are a lot of non-linear processes that are parameterized going on, models often produce too much precipitation or go to extremes...either cold or warm as the model is run out beyond a certain time period. Just look at all the GFS day 10-15 snowstorms in the winter that never happen!! anyway, these are my views.

 

But I agree we should be looking for alternate fuels and energy sources and in time these will become more viable economically.  I also support environmental causes and disagree with mankind abusing the environment. I also am not a staunch conservative either and do not watch FOX news!!!!  Imagine that!!! 

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Perhaps a picture can help. 

 

You can see that the earth was out of equilibrium when the LIA ended as solar and volcanic forcing rose. When they stopped rising, OHC and surface temperature stopped rising as much as well. When CO2 began to rise rapidly (outpacing aerosols) the earth lost its equilibrium again and OHC and surface temperature began to rise again.

 

We actually don't really know at all how OHC behaved before 1950, so your picture is speculative at best. Also, the Geomagnetic AA Index is a pretty good proxy of solar activity.. and can explain a huge fraction of the observed warming.. even part of the late-20th Century Warming.

 

fig6-ra.jpg

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We actually don't really know at all how OHC behaved before 1950, so your picture is speculative at best. Also, the Geomagnetic AA Index is a pretty good proxy of solar activity.. and can explain a huge fraction of the observed warming.. even part of the late-20th Century Warming.

 

fig6-ra.jpg

be careful. the sun has little effect on climate change. you should know better than to post this stuff on this forum. /sarc  

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be careful. the sun has little effect on climate change. you should know better than to post this stuff on this forum. /sarc  

 

Judith Curry has a nice thread on solar forcing right now, and it is really remarkable how the IPCC continues to insist that the only way the sun impacts Global Climate is through a small increase in brightness. I just finished reading a paper by Mende and Stellmacher.. and they attribute about half of the warming to solar forcing.

 

http://books.google.com/books?id=5QzIyN2hz4sC&pg=PA295&lpg=PA295&dq=solar+variability+and+the+search+for+corresponding+climate+signals&source=bl&ots=SLZKEiW5Gy&sig=1Tjz76l5OvEDLW3ca2Afdks0XoA&hl=en&sa=X&ei=OrhIUtORBbai4APquIDICw&ved=0CD8Q6AEwAw#v=onepage&q=solar%20variability%20and%20the%20search%20for%20corresponding%20climate%20signals&f=false

 

Beer et al. also found that 40% of the warming was due to solar forcing since the LIA.. with an additional 10-20% being due to natural variability. They find that natural factors and human factors have both been significant during the 20th Century warming phase.

 

http://pages-142.unibe.ch/products/books/qsr2000-papers/beer.pdf

 

The paper above has been cited over 200 times, so it is not "obscure" as Skier would like to say.

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Gotta explain the last 15 year divergence, however, when posting such a graph....

 

It's probably a result of other factors. Like I said, the sun can explain a large percentage of the warming in that chart.. but not all of the warming. That also does not mean that the sun was necessarily responsible for all of the warming before 1995. It likely wasn't. However, it was likely a significant contributing factor. The AA Index and SSTs match nearly perfectly until the super El Nino in 1998. A portion of the divergence could be also due to the anthropogenic forcing.

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We actually don't really know at all how OHC behaved before 1950, so your picture is speculative at best. Also, the Geomagnetic AA Index is a pretty good proxy of solar activity.. and can explain a huge fraction of the observed warming.. even part of the late-20th Century Warming.

 

fig6-ra.jpg

 

You complain about OHC data before 1950 being speculative and then show a graph of sea surface temperature back to 1850. Not much solar forcing since 1960 according to this chart.

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You complain about OHC data before 1950 being speculative and then show a graph of sea surface temperature back to 1850. Not much solar forcing since 1960 according to this chart.

SST data is definitely less reliable as you go back earlier in time. I would argue though that some data with uncertainties is more reliable than non existent OHC data before the mid 20th century.

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SST data is definitely less reliable as you go back earlier in time. I would argue though that some data with uncertainties is more reliable than non existent OHC data before the mid 20th century.

 

Older SST data needs to be corrected for measurement bias and uneven coverage. The SST data in this chart is not referenced and it doesn't look at all like the Hadcrut SST data. This chart is designed to mislead.

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Older SST data needs to be corrected for measurement bias and uneven coverage. The SST data in this chart is not referenced and it doesn't look at all like the Hadcrut SST data. This chart is designed to mislead.

 

 

I don't agree with his assertions, but the bolded I disagree with too...that looks pretty close to HadSST data...maybe need to dip the SSTs in the early to mid 1970s a little bit.  

 

 

compare_datasets_hadsst3_logo_large3.png

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I don't agree with his assertions, but the bolded I disagree with too...that looks pretty close to HadSST data...maybe need to dip the SSTs in the early to mid 1970s a little bit.  

 

 

compare_datasets_hadsst3_logo_large3.png

 

I agree that the shape of the two SST records are similar, but the temperature scales are widely different.  SL's chart has a min of about -0.6 in 1910 and a max of about 0.75 in 1998 for a min to max spread of roughly 1.4 C.  The HadSST chart has a similar minimum of -0.6 in 1919 but a max of 0.4 in 1998 for a min to max spread of just 1.0.  That's close to a 40% difference in observed temperature rise.

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I agree that the shape of the two SST records are similar, but the temperature scales are widely different.  SL's chart has a min of about -0.6 in 1910 and a max of about 0.75 in 1998 for a min to max spread of roughly 1.4 C.  The HadSST chart has a similar minimum of -0.6 in 1919 but a max of 0.4 in 1998 for a min to max spread of just 1.0.  That's close to a 40% difference in observed temperature rise.

 

I agree...it appears they need to shift everything post-1970 down about 0.1-0.2C to make the graphs match better...and perhaps up about 0.1C in the 1940s and 0.1C down in the 1950s.

 

The shift would cause the SSTs to not match as well in the 1960 solar peak though it would make the 1970s-1990s match up better.

 

 

But I was disagreeing with the assertion that it "doesn't look at all like Hadley SST data"...it does IMHO...though the former graph looks a bit bullish on the overall warming.

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SST data is definitely less reliable as you go back earlier in time. I would argue though that some data with uncertainties is more reliable than non existent OHC data before the mid 20th century.

Older SST data needs to be corrected for measurement bias and uneven coverage. The SST data in this chart is not referenced and it doesn't look at all like the Hadcrut SST data. This chart is designed to mislead.

Before the mid 2000's, 1500M or below coverage was virtually non existent compared to 2005 onward. Coverage is several hundred to maybe 1000 times better.

I have no idea about surface coverage

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Older SST data needs to be corrected for measurement bias and uneven coverage. The SST data in this chart is not referenced and it doesn't look at all like the Hadcrut SST data. This chart is designed to mislead.

 

You need to check where the data came from before you accuse me of misleading. The chart uses HadSST2, but filters out the temperature shift in 1946. While HADSST2 has it's uncertainties, it's generally considered to be a good representation of what SST variations have done over the last 150 years.

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Before the mid 2000's, 1500M or below coverage was virtually non existent compared to 2005 onward. Coverage is several hundred to maybe 1000 times better. I have no idea about surface coverage

 

You can see the massive uncertainties in measuring the near surface of the ocean, when compared to the sea surface temperature. 

 

gouretski_etal_fig1.png?w=640&h=659

 

It is interesting to see that a huge chunk of the near surface temperature increases occured before significant Carbon Dioxide increases.

 

http://www.leif.org/EOS/2012GL052975.pdf

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I agree...it appears they need to shift everything post-1970 down about 0.1-0.2C to make the graphs match better...and perhaps up about 0.1C in the 1940s and 0.1C down in the 1950s.

 

The shift would cause the SSTs to not match as well in the 1960 solar peak though it would make the 1970s-1990s match up better.

 

 

But I was disagreeing with the assertion that it "doesn't look at all like Hadley SST data"...it does IMHO...though the former graph looks a bit bullish on the overall warming.

 

It filters out the 1946 shift in temperatures, and therefore has a larger trend in SSTs than the unfiltered HadSST2 data.  

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I don't agree with his assertions, but the bolded I disagree with too...that looks pretty close to HadSST data...maybe need to dip the SSTs in the early to mid 1970s a little bit.  

 

 

compare_datasets_hadsst3_logo_large3.png

The overall upward trend is similar but the SST on his plot doesn't have the 1940s peak or the dip afterwards lasting into the 70s.. Makes a difference in evaluating the correlation 

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I don't agree with his assertions, but the bolded I disagree with too...that looks pretty close to HadSST data...maybe need to dip the SSTs in the early to mid 1970s a little bit.  

 

 

 

 

The chart is definitely designed to exaggerate any correlation by upping the 70s, and damping the 1970-present increase. It also somehow delays the decline of the aa index until after 1990. Here is a more accurate chart below. As you can see, there is not much correlation other than the coincidence that both parameters were rising for the first half of the 20th century (actually its an inverse correlation). 

 

Of course this graph is from 2003, and since then temperatures have continued to rise, while cosmic rays have continued to rise rapidly down up to early 20th century values (viewed as a drop on the chart). In short any correlation that existed, has completely fallen apart in the last 10 years (and really the last 30 years).

 

 

krivova_2003.gif

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The chart is definitely designed to exaggerate any correlation by upping the 70s, and damping the 1970-present increase. It also somehow delays the decline of the aa index until after 1990. Here is a more accurate chart below. As you can see, there is not much correlation other than the coincidence that both parameters were rising for the first half of the 20th century (actually its an inverse correlation). 

 

Of course this graph is from 2003, and since then temperatures have continued to rise, while cosmic rays have continued to rise rapidly down up to early 20th century values (viewed as a drop on the chart). In short any correlation that existed, has completely fallen apart in the last 10 years (and really the last 30 years).

 

 

krivova_2003.gif

 

The chart that involved HadSST2 filtered out the 1946 decline. This was because there was research that showed that at least part of it may have been due to instrumentation errors, which I have linked to in one of my above posts. To account for a lag between the AA Index and SSTs, the AA Index has also been advanced 7 years.

 

http://www.atmos.colostate.edu/ao/ThompsonPapers/Thompson_etal_Nature2008.pdf

 

Also, Solanki and Krivova's graph uses Neutron Counts to reconstruct the Cosmic Ray Flux over the late-20th Century. If you use Ion Chambers instead of Neutron Counts, you get a better fit to the late-20th Century Warming.

 

post-3451-0-92145200-1380753577_thumb.pn

 

I don't think that Solar has caused all of the warming. I think it has caused a larger warming than has been acknowledged by some though. Values from the Mende and Stellmacher and Beer et al. studies seem like a good estimate IMO.

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Of course this graph is from 2003, and since then temperatures have continued to rise, while cosmic rays have continued to rise rapidly down up to early 20th century values (viewed as a drop on the chart). In short any correlation that existed, has completely fallen apart in the last 10 years (and really the last 30 years).

 

I would not agree. In fact, the only temperature dataset that shows any sort of positive slope since 2003 is UAH.

 

post-3451-0-40674200-1380754363_thumb.pn

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Before the mid 2000's, 1500M or below coverage was virtually non existent compared to 2005 onward. Coverage is several hundred to maybe 1000 times better. I have no idea about surface coverage

 

There are some proxy methods for getting fairly precise SST or near surface ST, at least in the tropics, using isotopes in coral. Some of these records go back 500 years. Pretty cool stuff. Every method I've seen has the same looking graph over the past 100+ years so I'm pretty comfortable with the magnitude and trend. The deep water data is pretty limited pre-argo but see no reason it would not be following a similar trend. Could the magnitude of trend potentially be overstated? Sure.

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Before the mid 2000's, 1500M or below coverage was virtually non existent compared to 2005 onward. Coverage is several hundred to maybe 1000 times better. I have no idea about surface coverage

 

There are some proxy methods for getting fairly precise SST or near surface ST, at least in the tropics, using isotopes in coral. Some of these records go back 500 years. Pretty cool stuff. Every method I've seen has the same looking graph over the past 100+ years so I'm pretty comfortable with the magnitude and trend. The deep water data is pretty limited pre-argo but see no reason it would not be following a similar trend. Could the magnitude of trend potentially be overstated? Sure.

Isn't coral typically found in shallow water near shore? I would think this water would be very affected by local land temp swings, far more than most of the ocean and definitely more so than deep water.... Deep water, you know, where all the warming is hiding supposedly.

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I would not agree. In fact, the only temperature dataset that shows any sort of positive slope since 2003 is UAH.

 

attachicon.gifwoodfortrees.png

 

Ok the ENSO adjusted temperature has continued to rise.

 

There has been no sign of cooling as one would expect due to the huge increase in cosmic ray counts since 1980. Cosmic ray counts bottomed around 1980 and have been at early 20th century values since 2008 and yet temperature remains 1C above early 20th century temperature. If cosmic rays had even the slightest effect, we would have cooled due to the large change in cosmic rays.

 

In addition, there is no plausible mechanism by which cosmic rays effect climate.

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