Can we trust global warming predictions based on climate models?

Question

I remember when Hurricane Francis came over my home town in Florida and the Weather Channel, this is before the power went out of course, was giving us a 90% chance of precipitation for the day. I looked outside to see my bark porch flooded and winds lashing the palms. That 90% chance was the result of data entered into computer models apparently with a 10% margin of error. If these models give results like this can we really trust these global warming models? Especially when these models do not take into account variables such as atmospheric water vapor and location of weather stations?

Answer 1

No, we cannot trust the climate models.

"The claim by the IPCC that an imposed climate forcing (such as added atmospheric concentrations of CO2) can work through the parameterizations involved in the atmospheric, land, ocean and continental ice sheet components of the climate model to create skillful global and regional forecasts decades from now is a remarkable statement. That the IPCC states that this is a ‘much more easily solved problem than forecasting weather patterns just weeks from now’ is clearly a ridiculous scientific claim."
This quote was taken from "A Short Summary of Why Skillful Climate Prediction Is Much More Difficult than Skillful Weather Prediction," by Roger A. Pielke.
http://climatesci.colorado.edu/2007/05/23/a-short-summary-of-why-skillful-climate-prediction-is-much-more-difficult-than-skillful-weather-prediction/

Models that claim to predict climate 100 years into the future are worthless. The models were already wrong about Antarctica. See
http://researchnews.osu.edu/archive/anttemps.htm

Climate models used to predict short term regional climate are wrong more than half the time. This has been in the news. Peer-reviewed articles sometimes attempt to address this failure.
http://www.agu.org/pubs/crossref/2006/2006GL027654.shtml

Part of the reason climate models fail is that climate scientists have not bothered to learn from scientific forecasting the right methods to use. J. Scott Armstrong is one of the leaders of scientific forecasting. He audited the methods used by the IPCC to come up with their predictions and found they violated 79 principles of scientific forecasting. See his website http://www.forecastingprinciples.com/

Armstrong and Kesten Green wrote a paper explaining the audit of the IPCC and what they found. You can read the paper at http://forecastingprinciples.com/Public_Policy/WarmAudit31.pdf

After auditing the IPCC methods, Armstrong proposed a bet with Al Gore about global warming. Gore has not replied to his offer.

Another expert on predicting nature is Duke professor Orrin Pilkey. Pilkey is an expert on coastal geography. He has seen great many predictions about changing coastlines fail. He and his daughter wrote a book title "Useless Arithmetic."

Answer 2

Right now computer models are the best mechanism we have for such things as weather prediction or how global warming will play out over the next few years or decades. But there is a great unknown here because we don't know enough about our climate to predict how our weather will change over the coming years, This is why computer models are run over and over and changing the variables slightly and observing what difference those changes make. So if several computer models indicate a temperature change of 1.5 to 4.5 degree increase over the next fifty years then that range is best guide for what the future holds. Each time scientists run models they then watch how they play out over time and they get better at making predictions because those models get better over time. Having said all this scientists have been shocked by the opening of the Northwest Passage through the Arctic this summer because none of their computer models predicted that this would happen so soon. It is scary to think about, but we may have already reached the point of no return and global warming may continue to accelerate with more serious impacts every year. Global warming is real and based on the best science out there. People who want to deny that global warming is not a reality right now and that it could devastate this world as we know it are just like the holocaust deniers. Open your eyes and read the research or at least be open to considering this global problem.

Answer 3

You know, whether you trust climate models is totally up to you. If you don't, I can't think of the slightest reason that anyone else would care about that. The scientists seem to place value on them, but don't use them as their sole guide. I read the science news carefully, and apply the things I can to my own life. If you seriously want to debate the value of climate model ling, you are quite obviously in the wrong place. You need to take it up with the scientists, the IPCC for example. The people here aren't in charge of such things, in much the same way the people in Cars & Transportation are not the car companies or the airlines.

Answer 4

Yes. The fact that we can't predict short term weather has nothing to do with predicting long term climate.

Models work. Here's an example:

http://www.globalwarmingart.com/wiki/Image:Climate_Change_Attribution.png

More details here:

http://environment.newscientist.com/channel/earth/climate-change/dn11649

The fact is that the "signal" (statistical term) from greenhouse gases is so strong that the model doesn't need to be perfect to show that they are the main cause.

Water vapor is unimportant IN CAUSING WARMING. That's because water has a short "residence time", any excess falls out rapidly as precipitation. While CO2, with a long residence time, persists. More details here:

http://www.realclimate.org/index.php?p=142

Study after study shows the location of the stations is not contaminating the data.

T. C. Peterson (2003). "Assessment of Urban Versus Rural In Situ Surface Temperatures in the Contiguous United States: No Difference Found". Journal of Climate 16: 2941–2959

David E. Parker (2006). "A demonstration that large-scale warming is not urban". Journal of Climate 19: 2882–2895

Honestly, do you think 99+% of the scientists in the world don't understand the limitations of models, the role of water vapor, and how to check the data?

"The fact that the community overwhelmingly supports the consensus is evidenced by picking up any copy of Journal of Climate or similar, any scientific program at the meetings, or simply going to talk to scientists. I challenge you, if you think there is some un-reported division, show me the hundreds of abstracts that support your view - you won't be able to. You can argue whether the consensus is correct, or what it really implies, but you can't credibly argue it doesn't exist."

Dr. James Baker - NOAA

Good websites for more info:

http://profend.com/global-warming/
http://www.ucsusa.org/global_warming/science/
http://www.realclimate.org
"climate science from climate scientists"

Answer 5

this is totally very like asking "what training do maps modern". Maps are fashions of geography that could modern would issues on many scales, yet bypass away out maximum of actuality with the aid of fact it purely detracts from what you attempt to understand - soil variety would not remember plenty to persons who're attempting to maintain on with the interstate, to illustrate, even even with the undeniable fact that it became into considered necessary know-how to the developers of the gadget. a working laptop or computing device style of a actual gadget will contain as plenty documents as is mandatory to understand the variables you're analyzing. Milankovic cycles are important to the long-term climate, to illustrate, yet are understood nicely adequate which you do no longer would desire to place them right into a style this is gazing one hundred-3 hundred and sixty 5 days element. many circumstances an basic one-dimensional style will practice important constraints on complicated systems. evaluate the shaggy dog tale approximately "you're an engineer in case you have ever assumed a around horse".

Answer 6

Jim Hansen did pretty well with his model so we can trust climate predictions.

As for weather predictions though (which are completely different things), I don't think anyone really trusts them though (although they have been getting a lot better than they used to be).

Answer 7

good climate models come with probablities & caveats etc to give us the tools to make good decisions http://www.ipcc.ch
Weather forcasts include these, but the 2minute tv weather reports useuall omit them as people generally prefer someone else to take the decissions and make authorative statements.

trust is a personal/social issue, to do with who is in "our gang".
Do you choose global corp multi-millionaire board members;
or those given the absolute definitive word of "god", or someone who has designed and refined models, tested them against realtity

Answer 8

You can trust investment in Carbon offset trading cause even if GW ain't happening. The financially astute are gearing up to make bucks off it. Big media, big oil, big banks, big power, big Algore, all have a vested interest in keeping GW alive and well in the 21st century

Oh I'll bet the IPCC had one hellofa good time in Bangcock .

Answer 9

I think the question should be, can we afford to ignore the possibility that they might be right?

I don't know about you, but I'm not prepared to bet my children's lives that the IPCC has it wrong, especially when I don't see any huge downside to taking steps to prevent or ameliorate the effects.