Some global warming deniers assert that the global climate models (GCMs) used to analyze and predict climate change can be ignored because they are "untestable" or "have no predictive ability." In the words of "Mug Wump" on the amazon.com Science Discussion Forum "Global Warming is Nothing but a Hoax and a Scare Tactic:"
If you had any scientific evidence that human CO2 causes global warming, you would have produced it by now. Ergo, reality eludes you. Don't believe or argue with me. There are many, many scientists who once rubbed shoulders with the AGW idiots like brothers that can't take enough showers now to wash off the stink--they've come clean and have acknowledged that global warming alarmism is nothing but a hoax. Amaze us all and admit that simple fact. While you're at it, why not admit that GCMs have been shown to have zero predictive ability? Oh wait, you can't: that requires an understanding of math. It's a lot easier for you to stick to the a Leftist-libs' kind of 'truth' and continue sticking science and the search for objective truth in the back.
-Posted Tuesday, September 22nd, 2009, at 5:28 PM PDT.
Are the models, in fact, untestable? Are they unable to make valid predictions? Let's review the record. Global Climate Models have successfully predicted:
Seventeen correct predictions? Looks like a pretty good track record to me.
Are there problems with the models, and areas where they haven't gotten it right yet? Sure there are. The double Inter-Tropical Convergence Zone which shows up in some coupled models, ENSO variability, insufficiently sensitive sea ice, diurnal cycles of moist convection, and the exact response of climate to clouds are all areas of ongoing research. But the models are still the best thing we have for climate prediction under different scenarios, and there is no reason at all to think they're getting the overall picture wrong.
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|---|---|---|
| Troposphere warms, stratosphere cools | Manabe and Wetherald 1967 Manabe and Stouffer 1980 | Ramaswamy et al. 1996, 2006 De F. Forster et al. 1999 Langematz et al. 2003 Vinnikov and Grody 2003 Fu et al. 2004 Thompson and Solomon 2005 |
| Nights warm more than days | Arrhenius 1896 | Dai et al. 1999 Sherwood et al. 2005 |
| Winter warms more than summer | Arrhenius 1896 Manabe and Stouffer 1980 Rind et al. 1989 | Balling et al. 1999 Volodin and Galin 1999 Crozier 2003 |
| Polar amplification | Arrhenius 1896 Manabe and Stouffer 1980 | Polyakov et al. 2001 Holland and Bitz 2003 |
| Arctic warms more than Antarctic | Arrhenius 1896 Manabe and Stouffer 1980 | Doran et al. 2002 Comisa 2003 Turner et al. 2007 |
| Pinatubo effects | Hansen et al. 1992 | Hansen et al. 1996 Soden et al. 2002 |
| Last Glacial Maximum sea surface temperatures | Rind and Peteet 1985 | Farreral et al. 1999 Melanda et al. 2005 |
| Temperature trend versus UAH results | Christy et al. 2003 | Santer et al. 2003 Mears and Wentz 2005 Santer et al. 2005 Sherwood et al. 2005 |
| Water vapor feedback from ENSO | Lau et al. 1996 | Soden 2000 Dessler and Wong 2009 |
| Ozone hole effect on southern ocean winds | Fyfe et al. 1999 Kushner et al. 2001 Sexton 2001 | Thompson and Solomon 2002 |
| Hadley Cells expand | Quan et al. 2002 | Fu et al. 2006 Hu and Fu 2007 |
| Storm tracks move poleward | Trenberth and Stepaniak 2003 | Yin 2005 |
| Tropopause and radiating altitude rise | Thuburn and Craig 1997 Kushner et al. 2001 | Santer et al. 2003 Seidel and Randel 2006 |
| Tropical "super greenhouse effect" | Vonder Haar 1986 | Lubin 1994 |
| Constant average relative humidity | Manabe and Wetherall 1967 | Minschwaner and Dessler 2004 Soden et al. 2005 Gettelman and Fu 2008 |
| Increased coastal upwelling of ocean water | Bakun 1990 | Goes et al. 2005 McGregor et al. 2007 |
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| Page created: | 09/30/2009 |
| Last modified: | 02/09/2011 |
| Author: | BPL |