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Is it possible to accurately predict climate?

The earth's climate is described with GCMs (General Circulation Models or Global Climate Models). GCMs are complex, containing many input variables and positive and negative feedback loops. These models are simulated on supercomputers to create predictions. The IPCC's predictions are based on an aggregate assessment of several GCMs. Global Warming skeptics have suggested that climates are in fact so complicated that such predictions cannot be trusted.

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Agree
Experts In Climatology


RealClimate    Climatology Blog
Agree
Another common false statement, which some contrarians may also find support for from the Cohn and Lins paper, is that the climate system is not well understood. ... If this statement were generally true, then how could climate scientists make complex models – GCMs – that replicate the essential features of our climate system? The fact that GCMs exist and that they provide a realistic description of our climate system, is overwhelming evidence demonstrating that such statement must be false...
16 Dec 2005    Source

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Does unpredictable weather imply unpredictable climate?
   Disagree

Roy Spencer    Meteorologist
Mostly Agree
And now my old boss when I was at NASA (as well as James Hansen’s old boss), John Theon, has stated very clearly that he doesn’t believe global warming is manmade…and adding “climate models are useless” for good measure. Even I wouldn’t go quite that far, since I use simple ones in my published research.
29 Jan 2009    Source

Sub-Arguments Of This Expert:
Does unpredictable weather imply unpredictable climate?
   Agree

Ian Enting    Physics Professor, IPCC Lead Author
Agree
One of the things is that the climate system is very complex. It's not as complex as Senator Minchin would make out, it's not the most complex system known to man-the human brain I would probably rate higher, the development of life and so on-because Arrhenius could predict four degrees warming back in 1896 from doubling CO2.
14 Jul 2007    Source


Disagree
Experts In Politics


Don Aitkin    Politics Professor
Mostly Disagree
Despite all the hype and the models and the catastrophic predictions, it seems to me that we human beings barely understand climate. It is too vast a domain. Though satellites have given us a sense of the movement of weather systems across the planet, portrayed every night on television, we still know little about the oceans, ... the atmosphere... [, or the] solar energy and the effect of the sun's magnetic field on Earth, and only a little about the land. The Earth is a big place.
09 Apr 2008    Source

Sub-Arguments Of This Expert:
Does unpredictable weather imply unpredictable climate?
   Agree

Ambiguous or Flip-Flop
Experts In Astronomy


S. Fred Singer    Head of NIPCC, Astrophysics Professor
Agree
The startling element of Bond's results is the close correlation found when the global temperatures and solar-strength records are laid next to each other. ...we know that the linkage exists and is powerful... Computer models indicate that a 0.1 percent change in the sun's radiation could cause a 2 percent change in the Earth's ozone concentration, affecting atmospheric heat and circulation.
01 Feb 2007    Source


S. Fred Singer    Head of NIPCC, Astrophysics Professor
Disagree
While useful in experiments to study the sensitivity of changes in climate parameters, computer models are unsuited for predictions of future climate. [editors note: assuming all climatologists agree it would be *even harder* to predict climate *without* computers]
02 Mar 2008    Source



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0 Points      Oluseun Idowu      21 Apr 2009      Stance on Question: Mostly Agree
Although it is pretty difficult to accurately predict climate, I believe it is very much feasible to continue to achieve higher levels of accuracy in climate predictions. From historical standpoint, and based on the present performance assessment of climate models, one would agree that climate modeling and, use and interpretation have improved over time.

We know that processes in the atmosphere are not perfectly predictable in a deterministic sense because the atmosphere is regarded as a non-linear dynamic or “chaotic” system. Therefore, the dynamic flow of the atmosphere is inherently non-predictable.

We also know that many physical parameterization schemes have been introduced in efforts to resolve physical processes in the atmosphere, such as cloud processes, rainfall and radiation fluxes, which all also have influence on the atmospheric flow dynamics. Our ability to predict atmospheric flow and processes is also restricted by our limitations in spatial as well as temporal observations of weather. In practice, model surface conditions are simplified and homogenized and the atmosphere is regarded as a medium that consists of square grid boxes in order to facilitate the mathematical treatment of the atmosphere. Atmospheric turbulence which plays an important role in the atmospheric convection is also another small-scale process that is difficult to resolve analytically.

The inaccuracies caused by these estimations of reality in climate models are a result of limitations in resolving complex processes that occur in the atmosphere. It is also important to know that climate models need strong computers to simulate estimated atmospheric flow and processes in order to generate predictions – an asset or luxury many meteorological centers simply cannot afford. Because of these limitations, climate models are subject to systematic errors and biases.


0 Points      Tyler      07 May 2009      Stance on Question: Mostly Agree
I agree. Although climate models can assist in giving us an idea about climate change, they are somewhat limited. They are subject to systematic errors and biases. However, with an increasing knowledge and further research abilities, I believe these models can serve as an excellent tool allowing us to focus deeper into the subject of climate change. Further research is needed in order for climate models to be more effective.