rb1957 said:
I think both sides [question data/research] regularly, with or without malice or intention.
Yes, that’s true. However, when one side questions the data/research, they publish peer-reviewed papers discussing the matter. When the other side questions the data/research, they make a blog post about it. Now, for those that distrust the entire peer-review process/scientific institution, this difference will matter little to them...but their opinion matters little to me. Especially when one of the more notable cases of "pal-review" involved skeptic papers, not "conformist" papers (i.e. Soon and Baliunas 2003 and Chris de Freitas). However, I don't even care about that because saying "sometimes bad science gets through to publication" (both skeptic and "conformist") is obvious and well-known; peer-review is not perfect. However, to extend this to think, "Therefore, blogs should be considered more reputable than peer-reviewed journals" or "Therefore, peer-review can be dismissed with a wave of the hand" is ridiculous.
rb1957 said:
personally, i believe that climate is a horribly complicated thing, and when i'm told "the one and only thing that's causing this trend is AGHG" i say "BS"…
While, yes, climate is extremely complicated, most of the complications come from interactions within the climate system (internal variability, feedbacks etc.). The hard question in climate science is determining long-term effects. However, there are actually relatively few external factors that can influence long-term changes in Earth’s energy budget that can lead to long-term, significant changes in global climate (i.e. solar variations, orbital/tilt variations, massive volcanoes, asteroids, large-scale anthropogenic actions). So prescribing attribution is a (relatively) easy question within climate science because (1) there is only a small number of external factors that it could possibly be and (2) the exact manner, the rate and extent these factors influence climate are quite different and therefore discernible from each other.
This distinction is well represented in the science. The IPCC has 95% confidence (“extremely likely”)
in AR5 (up from 90% in AR4) that “more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas concentrations and other anthropogenic forcings together.” However, the confidence in sensitivity (i.e. the extent of long-term effects) is lower and the range is quite high:
AR4 – “likely” (>66%) range 2 deg C to 4.5 deg C, best estimate “about 3 deg C” and “very unlikely” (<10%) less than 1.5 deg C
AR5 – “likely” (>66%) range 1.5 deg C to 4.5 deg C, no best estimate and “extremely unlikely” (<5%) less than 1 deg C and “very unlikely” (<10%) greater than 6 deg C.
(If you’re interested in discussing climate sensitivity, I’d encourage you to read and post in
my thread on it.)
rb1957 said:
My 2nd issue is that I don't believe that the FFs we burnt yesterday are changing the climate today.
You need to separate fast and slow feedbacks. The carbon we release today that makes its way into the atmosphere, will have a very slight impact on the energy budget of the planet tomorrow. In high enough quantities, these start to have a notable impact – represented by fast feedbacks. Overtime, the initial impacts begin to have secondary, indirect impacts that develop over decades and centuries – represented by slow feedbacks.
The FFs we burnt yesterday are (slightly) changing the climate today. However, the full impact will not be realized for decades or centuries. (You’ve mentioned this before and I came across a great article that described this a while back and thought of showing it to you (but it would have been out-of-the-blue) Now I can’t think of where I read it. If I come across it again, I’ll post it.)
rb1957 said:
my 3rd issue with AGHG is that if burning FF is the worse thing we've ever done, why are we still doing it ? why isn't petrol $10/gallon (/liter?) ? and the resulting funds directed towards energy solution that don't create GHG ? because it's politically unacceptable.
Well, it’s not the “worst thing we’ve ever done” but the rest of the questions are exactly the same as those the people on my side ask. And your answer is spot on as well.
People don’t like to think long-term. Politicians sure as hell don’t like to think long-term. It’s a bad mix for creating policy that might be hard in the short-term but is beneficial to us in the long-term. Furthermore, and arguably more importantly, it works against the consumption-based capitalist zeitgeist. The capitalist structure requires increasing growth and consumption to sustain itself. Asking people to consume less works against this. So it's not just a political issue but a deep-seated cultural issue - which is why I'm doubtful that we can voluntarily (without regulatory and taxation reform) change our consumption habits (as cranky108 suggests).
rb1957 said:
and straight to my 4th problem, this is a political problem and solution, not a scientific one.
I’d broadly agree with this.
Climate Science is a risk assessment exercise . What are the risks of us not mitigating climate change and what are the costs to do that? Scientists set up the inputs for the risk assessment but it’s up to the people and politicians to determine what actions (if any) are needed.
As you stated in your first problem, the climate is a complicated beast. Establishing an exact value for the temperature in 2100 and the exact dollar value of the related impacts is impossible. The best science can do is create a probability distribution function (PDF) for the sensitivity, both TCR and ECS (and they have - WGI). Scientists and economists then need to examine the potential social, economic and environmental impact based off the PDF of sensitivity (and they have – WGII). Then you need to examine the economic benefits (or lack thereof) doing something to mitigate the damage (and they have – WGIII) (…it’s almost as if there is a method to the IPCC’s madness!). With this information, the people and the politicians need to determine what the “tolerable risk” is and how much mitigation is necessary.
We engineers should understand this very well as many of us do Failure Modes and Effects Analysis (or similar). We pour over the data, calculate the risk and present that to management. Often, however, management looks at the costs to implement the risk avoidance measures and look for ways not to do it. “It’s awfully expensive! Are you sure it’s needed? Look at all this uncertainty in your numbers! The risk could be minimal. The risk is probably minimal. The risk is minimal. We don’t need these risk avoidance measures.”
The issue is that they look at the cost of reducing risk, don’t like it and then actively search for ways to justify not needing it. This is how most skeptics approach climate change science. They are told that reducing the risk requires costly, difficult reductions in CO2 emissions, don’t like that and then combed through the evidence, searching for the slightest fault and then extrapolate that to justify a “do nothing” position. But this is not how you do risk assessment as we engineers should know better. You don’t look at the range of possible outcomes, pick the smallest possible risk (despite it having very low probability), ignore the outcome with the highest probability and conclude the “do nothing option is best”.
