skierinvermont

Nonsense, as I've demonstrated to you several times. There is much data that has been adjusted both up and down. Deniers just focus on the data that has been adjusted upwards. Also if reality is an "up trend" but you have an inaccurate method of measuring it, more often than not the method will yield a result which shows a lower trend than reality. Improvements in accuracy will result in upwards revisions. Which is essentially what happened with the ARGO floats. We had inaccurate measurements yielding wacky inaccurate results that were averaging out to not much trend. When the measurements were fixed, or the inaccurate floats removed from the analysis, the actual warming trend that was occurring in reality became prevalent in the data.

Yes stupid could definitely be placed on #1, and possibly #2 although #2 as I described it is a little closer to the scientific opinion than #4 is. I do not think the terms alarmist, skeptic, or denier are any less subjective, loaded and/or pejorative than the terms arrogant, stupid, biased, or misled. Alarmist and denier are clearly pejorative. Skeptic is intended to stake out a claim of scientific superiority which does not exist. Instead of using these conventional loaded and pejorative terms, I made the pejorative and loaded nature of these terms more obvious and less subtle. If you can think of a term to describe alarmists and deniers which has no value judgment inherent in it, I would consider that term. But I do not wish to use labels which give false validity to opinions which are irrational. The value judgment within the label and description should either be nonexist (I don't know if this is possible) or direct, obvious and clearly stated (rather than subtle). Also Will, I don't think my intolerance of #1 is any less than it is for #5 or #6. I've spent plenty of time arguing with group #1 on this forum (Terry, Vergent usually, sometimes Phillip or Friv). And my tolerance of group #2 is similar to group #4, although as I said above I think the way I described it group #2 is closer to the scientific opinion than #4 is. #2 is a group that follows the science but just has a consistent bias towards the worst case scenario. #4 not only has a bias towards the best case scenario but also steps outside of the range of scientific uncertainty at times.

Indeed it is, which is why you can see the smaller confidence intervals during that period than pre-2003. However, you can see that there is more than enough confidence to be certain OHC was rapidly rising during the 80s and 90s.

It's true that if we look at just the last 15 or 20 years, a little cooling has occurred in U.S. and European winters, but it's a short enough period and a small enough amount a lot of other factors could explain. I don't think there's been much change in aerosols in those places over that period (maybe a small further decrease I'm not sure). China and SE Asia has also witnessed no winter warming over that period, which could reasonably be explained by the big increase in aerosols there. While one might expect the aerosol effect to be slightly stronger in winter, winter temps are also more effected by weather patterns and we it reduces the time period of data for the analysis from 240 months to 60 months (DJF). Given the above, it still is probably better to use annual trends to look for possible aerosol effects just because you get 4X more data. If we look at annual trends, we definitely see that China and SE Asia has been one of the slowest warming areas the last 20 years (no warming over much of that area). We still see it looking just at winter as I said before, but there's a lot more global spatial variability because of the smaller amount of data. The annual analysis is better because it gives us 4X more data and a clearer picture.

Oh and the response by the reviewer that I read points out that numerous other surface and satellite sources which have been considered fairly reliable disagree with the findings of major global brightening.

Your second study concerns only the land area of China and is written by chinese scientists and I am not sure the quality of the the review.. I tend to be speculative about any academic research coming out of china. Anyways, it only concerns the area of china so it's not all that interesting to this discussion. Your first study claims a 2.7W/m2 increase in solar radiation reaching earth's surface. This is an incredible finding. If this were the case, there should have been a massive amount of warming. Incredible findings require incredible evidence. This paper was just published and nobody has cited or responded to it, although I did find one very critical response by a reviewer.

Pinatubo studies do not provide evidence of lower climate sensitivity. They provide evidence of climate sensitivity within the IPCC range. We've had this discussion before. There are some legitimate studies giving speculative evidence of climate sensitivity 1.5-2C, but there aren't any rigorously reviewed good studies suggesting anything lower than 1.5C is likely.

This simply reinforces my point. Rapid warming occurred in the industrialized nations after passage of clean air acts during the period 1980-1997. My chart also illustrates this by showing how much warming the 1990-2012 period was relative to the 1950-1970 period in the industrialized nations in winter.

Again, all of those phenomenon are the last 10-20 years Cohen is talking about. I was talking about the last 40 years or so. As you can see from my chart above, a lot of the warming since 1970 has come from already industrialized areas (and arctic amplification).

Here's the chart FWIW. The UK's warming looks pretty pronounced compared to the surrounding ocean and much of the rest of the NH. It's also interesting to me that Europe and central Asia warmed faster than the arctic or even norther Asia. Almost like a stripe of aerosols had been lessened blowing across the continent. Usually it seems like the fastest warming is a bit farther north than that.

It looks like Cohen is only looking at the last 20 years.. most of the brightening occurred before then. If you compare 1950-1970 (aerosols era) vs 1990-2012 (clearer air), there is solid warming over the industrialized areas. Including during winter. In fact, the UK, Germany and northern Europe saw some of the fastest warming in winter on earth (1-2C in the UK and Germany, 2C+ in scandanavia).

1. Lifespan of aerosols is short so effect must be small. False. Surface and satellite based measurements show solar dimming due to aerosols. Aerosols are short-lived, but emissions are high enough that they accumulate in significant concentrations before the end of their lifespan. If we stopped all aerosol emissions, aerosol concentration would plummet (unlike long-lived GHGs). 2. Faster warming in the northern hemisphere is evidence that aerosols have smaller RF than most scientific studies say. False. The NH is projected to warm faster for numerous reasons which may not be cancelled by aerosol forcing roughly 25% the strength of GHG forcing. In addition, you can observe that within the NH, the areas of highest aerosol concentration have warmed the slowest. In fact, the SE U.S. is one of the slowest warming regions on earth. While warming in Europe has generally been .5-1C, warming in adjacent North Africa, Scandanavia, and eastern Europe has been 1-2C.

To introduce some facts into this discussion, the IPCC gives the RF from well-mixed GHGs as 2.8+/-.3Wm/2. The RF for aerosols is -.7W/m2, and the AF is -.9W/m2 (-.3 to -1.5W/m2). They say there is "high confidence" that aerosols have offset a substantial portion of GHG forcing. Best guess appears to be 25%.

That's not true, if you think about it. There was a lot of CO2 warming built up in the industrialized areas by 1980. With the brightening that occurred, this CO2 warming simply became apparent. Many of the areas that warmed pre-1980 because of CO2 and their lack of industrialization are now seeing industrialization and a pause in warming.

Please show these posts. I've been aware of these studies for quite some time, and have been suggesting that there is some possibility for an ECS <2C for quite some time. I have said, and still would say, that anybody saying that climate sensitivity is probably <2C is biased and not looking at the full body of evidence. Personally I think the most likely range is 2-3C, but there's no evidence that can rule out anywhere from 1.5-4.5C.

It doesn't matter whether the temperature correlates or not. There are a million factors interacting all at the same time, so expecting any single one or two of them (say aerosols+CO2) to correlate perfectly to temperatures is stupid. The endless teasing out and eyeball comparison of charts that goes on here and across the blogosphere is completely scientifically useless. Aerosols are literally blocking out the sun. This causes cooling. This is an indisputable fact. Aerosols have increased rapidly throughout the last century, until 1970 when their rise slowed. The period of fastest rise was the 1950s and 1960s relative to CO2 concentration, which may have had something to do with the lack of warming in this period. There could have been 100 other factors at play as well. We may never know exactly how all of these factors interacted in the 1950s and 1960s. But it remains indisputable that the blocking out of the sun by aerosols this century has caused major cooling.

Climate sensitivity (warming per doubling of Co2 concentration) is probably the best way to break down peoples opinions into categories. Since you've all used loaded language in you labels, I'll continue with the tradition: 1. Extreme alarmist: believes or focuses solely on the high end or even higher than the scientifically accepted climate sensitivity (>4C). Focuses solely on the worst case consequences and denies or ignores all benefits. 2. Alarmist: believes or focuses on the high end of scientifically accepted climate sensitivity (3-4.5C). Focuses usually on the worst case consequences and acknowledges few of the benefits. 3. Scientifically grounded: acknowledges the full range of scientifically accepted climate sensitivity (1.5-4.5C). May lean slightly one direction or another within that range based on a good-faith effort to objectively interpret the evidence with assistance of peer-reviewed literature, but acknowledges all of the uncertainty and the lack of concrete evidence. Has a balanced understanding and acceptance of the various consequences and benefits and the evidence that on net the consequences will be negative. A moderate to high level of mitigation is warranted, and adaptation cannot be relied upon solely. 4. The biased/arrogant/confused/misled lukewarmer category: believes or focuses solely on the low end or slightly below scientifically accepted climate sensitivity (1-2C). Ignores the evidence that climate sensitivity is probably higher than 2C. Often an undue focus on the benefits of AGW, or downplaying of the consequences. Possibly believes that the benefits of AGW will outweigh the consequences. 5. Denier/stupid: believes in a climate sensitivity below the scientifically accepted range (0-1.5C). Usually focuses on the benefits of warming and downplays the consequences. Probably believes that the benefits of warming will outweigh the consequences. 6. Extreme denier/stupid: believes CO2 has little to no warming effect. If warming did occur, it would be good.

True, which is why "low to medium confidence" in these conclusions should be stressed. As I pointed out above though, the period since 1970 has seen a strong increase in droughts concurrent with the period of fastest warming, so we may be beginning to witness the increase. If climate models are to be believed, drought frequency/intensity since 1980 would probably have been slightly lower.

How is acknowledging the obvious fact that human aerosol emissions have caused very large negative forcing and cooling "extreme" or "alarmist?" Do you deny that a significant fraction of the sun's SW radiation does not even reach the surface of the earth anymore because of these aerosols, a phenomenon known as "global dimming" which has gone so far as to even slow the growth of plant life on earth? You cannot simply wish these facts away. It is yet another nail in the coffin of denialism. The earth would have warmed far more if we were not literally blocking out the sun with aerosols.

The long-term trend on drought in the central U.S. is close to zero. The trend during the period of fastest warming, since 1970, is strongly towards more drought. Without the warming in this period we would probably be closer to 1940s-1960s drought frequency and the long-term trend due to the massive 1930s aberration (which might also have had something to do with land-use feedbacks) would be even more negative. The effect on frequency and intensity thus far is likely quite small, given the increase after much more warming may still only be modest according to some (Hoerling and peers). Reporting on the issue should always stress this using the 'loaded dice' paradigm instead of blaming the event entirely on AGW. Actually "loaded" might still be too strong of a word in this case, but you get the idea and I think we pretty much agree. I just don't agree blaming the drought on AGW is ignorant or false. Depending on exactly how the blame is ascribed, it would be more like an exaggeration.

I'm not saying his science is wrong, but he ripped into Hansen pretty hard (probably a little harder than was scientifically deserved given the great uncertainty in this field) and the way he went about it was beyond normal criticism you see between scientists. For example, when Trenberth criticized Hoerlings studies, he wasn't quite so belligerent about it. i think Hoerling and his co-authors are making good faith efforts to interpret evidence objectively and they are doing good science. I'm just saying that if anybody could find evidence that central U.S. drought would not increase, it would be Hoerling, but even he concludes that there will be a modest increase. Other studies find a larger increase. We shouldn't be so quick to assume either party is right. And we definitely should not ignore the overall probability that drought in the central U.S. will increase with AGW. Rising temperature will cause an increase in drought without a pretty solid increase in rainfall to go with it, which does not appear likely.

The increased temperature trend likely outweighs any small increase in precipitation. At least this is the conclusion of most climate models, climate experts, and the IPCC which gives low to medium confidence of increased drought risk in the central U.S. I see little reason to disagree with this conclusion. Even Hoerling whose "schtick" seems to be trying to one-up and attack Hansen and others forecasting dire consequences acknowledges CO2 forcing probably drives a "modest" increase in drought risk.

I don't believe that your quoted portions and links are saying what you think they do. There is a difference between drought and precipitation. Precipitation has and is expected to continue to decrease over the SW states WY,CO, NV, UT, AZ, CA, NM. Precipitation is not expected to change much over the central U.S. and has actually shown slight long-term increase thus far. However, precipitation is very different from drought. Because surface temperatures are rising, evapotranspiration is higher. This is why the central U.S. is modeled to see drying. Even the passage you quote refers to Hoerling's finding of "modest" modeled drying. Other methods of modelling soil moisture find more severe drying. I would feel pretty confident that the drought in CO, WY, AZ, UT, NV and CA was made more likely and exacerbated by climate change given the long-term drying that has occurred and is projected to continue to worsen. The Great Plains drought is less certain but the evidence generally points to future drying of this region. The 2012 drought was probably made slightly more likely and exacerbated by this forcing, although we can't be quite as confident in this conclusion as we can be for the southwest.

Blaming the 2012 drought on CC isn't ignorant at all. It's probably correct. CC is supposed to cause summer drying and warming (the two primary factors driving drought) over much of the U.S. and especially the western U.S. CC has probably made droughts like last year more likely.

Ok what's your point Jonger?