Grant was not even close to being fat in the civil war time frame.
Comment on ‘Pause’ discussion thread by timg56
↧
↧
Comment on ‘Pause’ discussion thread by Bill
That is very good, Judith. It makes several good points. It is one thing for commenters on a blog to fudge the truth, but scientists and the agencies they work for should play fair.
You don’t make a big deal out one data release when it shows what you want it to show and then next time release it quietly when it shows less warming. The point about giving the error bars on the trend lines and being sure to be clear about whether it is significant is also a good one.
It was only in the last few years that Santer and others showed that you would need a stretch of 15-17 years without warming before it was necessarily significant. To pretend now (as some on this blog seem to) that they knew all along it is not unusual to have 15 years without warming is indeed being economical with the truth.
↧
Comment on Alternative approach to assessing climate risks by mwgrant
First, thank you for posting the audio of your talk. It was interesting and easy to listen to. I had thought 24 slides for the time was ambitious–and it is for many presenters–but you are exceptionally efficient. Things flowed. When I looked at the slides alone nothing clicked in my worn brain, but the slides and audio…well, damn nice job. ‘nuf said.
Second, your characterization and critique of GCMs from the perspective of application in decision processes make some good points that need to be repeated time and again. However, refocusing the modeling approach alone is not enough. The expectations of the policy makers regarding the role (informing) and limitations of modeling in decision processes also needs some refocusing.
↧
Comment on Alternative approach to assessing climate risks by Joshua
This seems to me like a very interesting approach. Kind of cuts above the petty bickering that fills up so many jr. high school lunchroom cafeteria tables.
↧
Comment on ‘Pause’ discussion thread by kim
Simples, really, lolwot. TSI varies only 0.5%, so your(our) recent solar minimum had minor, probably indistinguishable, effect. The real solar cause of major climate effect is…..well, come back after the pause that refreshes our sponsors, this story is breaking, but someone’s got to pay the bills.
================
↧
↧
Comment on ‘Pause’ discussion thread by kim
Mike’s is funny, mine’s just sad.
============
↧
Comment on Alternative approach to assessing climate risks by David L. Hagen
<b>First fix corrupt politics on flood plain development – then adapt to anthropogenic global warming. </b>
Consider the challenge of “climate change” evaluation for a city built on a flood plain and the city council promoted “development” in areas where the “probable” flood level was less than half the historic flood level. The “climate change” contribution appears negligible compared with the challenge of corrupt city government. See the report of the Brisbane flood of January 2011. <a href="https://www.google.com/search?q=brisbane+city+council+flood+plain+probability&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a" rel="nofollow">The 2011 Brisbane Floods: Causes, Impacts and Implications.</a> Robin C. van den Honert, and John McAneney, Water 2011, 3, 1149-1173; doi:10.3390/w3041149
See the consequent <a href="http://www.brisbane.qld.gov.au/community/community-safety/disasters-and-emergencies/types-of-disasters/flooding/index.htm" rel="nofollow">2012 Brisbane interim plan.</a>
New Orleans has similar problems having had inadequate defenses against the Category III hurricane Katrina when the region is known to be in danger of Category V hurricanes. Contrast the Dutch for prudent flood planning.
Demetris D. Koutsoyiannis et al. have been developing <a href="http://itia.ntua.gr/en/documents/?title=flood&authors=&supervisors=&proj=&tags=" rel="nofollow">flood prediction and design methods </a> incorporating climate persistence using <a href="http://itia.ntua.gr/en/documents/?title=hurst&authors=&supervisors=&proj=&tags=" rel="nofollow">Hurst Kolmogorov Dynamics. </a>
I strongly endorse the sanity of your "alternative approach to assessing climate risk".
↧
Comment on ‘Pause’ discussion thread by Faustino
The GWPF of course includes highly experienced policy-makers and policy advisers, the kind of people who I hoped would be invited to the RS workshop.
↧
Comment on Alternative approach to assessing climate risks by Joshua
Stakeholders means stakeholders. The difficulty of choosing participants is not a reason to reject the process. There have been many successful products in the face of highly complex and contested problems that have resulted from stakeholder engagement. One key principle of participatory processes of that type is that the playing field should be leveled, and participants should be given equal power in affecting outcomes to the extent possible.
↧
↧
Comment on Alternative approach to assessing climate risks by David L. Hagen
PS I really must protest the ambiguity of today's English language, when the "norm for engineering and regulatory science" is considered to be having "a lack of formal model verification & validation"!
(<a href="http://curryja.files.wordpress.com/2012/10/rs-uncertainty-12.pdf" rel="nofollow">in slide 4)</a>
↧
Comment on Alternative approach to assessing climate risks by willard (@nevaudit)
> One problem is the tendency for some stakeholders to perceive and treat projections as forecasts. Indeed, it is difficult to communicate exactly what climate projections mean from a decision standpoint— they simulate what might happen under some conditions but do not preclude other outcomes.
I am shocked.
↧
Comment on ‘Pause’ discussion thread by Faustino
Joshua @ 8.45: reinforces my concerns about “government failure.” And about ideologues, I’ve never been an ideologue but earlier in life I knew many. My views are based on my knowledge, experience and understanding rather than a pre-defined position, and are moderated by self-knowledge, including of my weaknesses and ignorance.
↧
Comment on ‘Pause’ discussion thread by Paging Al Gore: Global Warming Stopped in 1997
[...] an Oscar and a Nobel Peace Prize. The film and book came out in 2006, in the middle of the “pause” in the rise in global temperatures. Now that’s what I call inconvenient. Here’s [...]
↧
↧
Comment on Recent challenges to the credibility of climate science by property lawyers
What’s Going down i’m new to this, I stumbled upon this I’ve discovered It positively helpful and it has helped me out loads. I am hoping to give a contribution & help other customers like its helped me. Great job.
↧
Comment on ‘Pause’ discussion thread: Part II by srp
If the following double-posts, I apologize, but it vanished after my first attempt and didn’t appear here when I refreshed through the blog front page.
The case for assuming that AGW matters is, in statistical terms, much like the hypothesis that broad-based stock indexes are good long-term investments. There is an upward secular trend but lots of plateaus and prolonged downturns and it’s easy to find windows that give different impressions. We know about the main external forcing, economic growth, and confounding forcings like tax and monetary policies.
The differences, it seems to me, are that the stock market has no known equivalent to PDO and the other oscillations; stock markets don’t have to worry about millennial-frequency factors; the fraction of economic output captured by earnings doesn’t vary as much as the distribution of heat across oceans, ice, atmospheric layers, land, etc.; and there is little reason to be concerned about time-varying sensitivity in the economic growth–>stock index relationship over long periods of time.
↧
Comment on ‘Pause’ discussion thread: Part II by David Appell
Re: “Concerns about data processing” — have you published papers about these concerns? As a scientist, I’m sure you know that’s where the rubber meets the road.
The most troubling aspect of today’s climate science is the way certain scientists — on both sides — have preconceived positions, and reflexively align with any findings that support them and casually dismiss (as here) anything that does not.
It’s very disconcerting. Of course, there are journalists who will give you inches. But dueling articles aren’t science, and this type of approach is ruining climate science. Historians will not look favorably on these times.
If you have reasons that the Argo data is false, present them. Vague insinuations do not stand.
↧
Comment on ‘Pause’ discussion thread: Part II by Joshua
Interesting logic:
Judith says:
Nuccitelli argues that the models are right, and therefore greenhouse warming dominates over natural warming. I argue that climate models are imperfect and incomplete, a statement that no climate modeler on the planet would argue with.
So Judith compares a statement that models are imperfect with a statement that models are right – not a parallel comparison.
The implication, just as in the Rose article that Judith applauded (while noting inaccuracies in how she was quoted w/o considering how someone who misquoted her might just do the same with others), is that others have said that the models are “perfect.”
Please provide a quote, Judith.
↧
↧
Comment on ‘Pause’ discussion thread: Part II by Ammonite
What is the likely best predictor of changes to globally averaged temperature across the next 10 years: +0.00C or +0.16C? If the concept of a “pause” is to have any weight it either needs to have predictive power or it needs to be of sufficient duration to undermine climate sensitivity estimates in a material way.
Foster and Rahmstorf 2011 strip out leading sources of natural variability (ENSO, volcanic eruptions and solar strength)to show that both satellite and ground based temperature systems have risen consistently at ~+0.16C/decade decade on decade for the last 30 years. The factors driving this trend produce consistent effects (whatever comprises them) and the trend is clearly up. In F&R the trend reaches significance for intervals down to ~5 years.
Don’t like F&R (or Lean and Rind)? Object to their TSI measure? Think they left out significant sources of natural variability? Question their motivations? How about a simpler trend estimate approach? Divide the monthly temperature series into El-Nino, La-Nina and neutral months. Run a regression through each. The results are the same in each case, positive trends of similar magnitude.
So the underlying trend is up as derived from observable behaviour. Does the concept of “pause” have predictive power? No, not given the consistency of this trend. Maybe we will have another couple of years of La Nina followed by Mt Fuji blowing its stack… but the point of natural variability is that it tends to range +/-0.2C about this trend and +0.2C represents only 12.5 years at the current rate of increase.
So, given a ~+0.16C/decade trend, does this undermine climate sensitivity estimates in a material way? Knutti and Hegerl 2008 show a median sensitivity of +3C. The lukewarm argument is that climate sensitivity is less than +2C. Considerations (and rubbery figures), given model mean estimates of +0.2C/decade:
1. *If* model evolution is correct but consistently overestimated: 3C*0.16/0.2 = +2.4C. Note that this is reasonably consistent with instrumental estimates in Knutti and Hegerl.
2. Suppose instead we take the lowest trending system (UAH at 0.14C) and drop it a further 0.02C for effect. This would imply +1.8C, a narrow margin at best. (Note that it’s possible that models over-estimate transient sensitivity but under-estimate the timeframe to reach equilibrium. It’s possible that +1.8C is “worse than we thought” – consider arctic behaviour. It’s very possible, given developments in shale oil and coal extraction technologies that we can more than double atmospheric CO2…)
Is model evolution likely to prove correct? Will the current underlying trend prove consistent? What percentage of the trend is due to anthropogenic forcing? How reliable are aerosol estimates? Will negative feedbacks undermine the assumptions above? These are open questions. For now let’s at least acknowledge that the underlying trend is up and broadly consistent with the AGW hypothesis. Let’s also acknowledge that natural variability of +/-0.2C is quite capable of flattening out the temperature graph for extended periods without invalidating this observation.
Foster and Rahmstorf (2011): http://www.skepticalscience.com/foster-and-rahmstorf-measure-global-warming-signal.html
Lean and Rind (2009): http://www.skepticalscience.com/lean-and-rind-estimate-man-made-and-natural-global-warming.html
Knutti and Hegerl (2008): http://www.skepticalscience.com/working-out-climate-sensitivity.html
↧
Comment on ‘Pause’ discussion thread: Part II by John S.
To disabuse yourself of the notion that the present 35-year regressional slope can be linearly projected into the future, take any credible,century-long temperature time-series and plot the slope as a function of the latest year included in the calculation. You’ll be surprised by how quickly the “trend” changes.
↧
Comment on ‘Pause’ discussion thread by Jim Cripwell
timg56, you write “I’m guessing they have to rely on model output to do the latter.”
I like your second paragraph. Another way of looking at the same thing, is as follows. If CAGW is correct, and global temperatures are, indeed, going to rise to very high levels by 2100, then at some point the rate of rise of temperature must be significantly greater than your 0.05 C per decade. Unless and until this happens, I am not going to believe in CAGW.
↧
More Pages to Explore .....
