The failure of global climate change models: scientific hysteria

Posted on August 30th, 2008 in Environment,General,Science by Robert Miller

No subject in the history of science has depended more on models and computer simulations than the science of global climate change. If you look back into our history, our knowledge of the distant past has been derived from studies of the the geological and fossil record that have been going on for more than two hundred years. And increasingly the view we get from these studies is that cataclysmic climate change can occur. But all of the past events have not been created by humans, but from other causes. If you try to look forward, by predicting our future climate conditions, it all comes from computer models and simulations that are extremely limited in their capacity to incorporate all the variables, primarily because the variables themselves are insufficiently understood. Events in the last few years have made it very clear: we don’t understand the variables that we need to know about in order to generate global climate change models that can tell us something which will give us confidence about our future. In the past year, we have witnessed the utter collapse of models that have proven the conservative nature of science and the scientists who study global climate change. There may not be enough time left to fix the problem. Climate models are being scrapped or rapidly revised to see if better predictions can be achieved by exploding the models to include as much as possible. I tend to think that this mass hysteria is going to fall short, simply because of the scale of the problem. I have spent a good part of my scientific career developing models of nerve cells, so I know something about how long it takes to get models that have good accuracy and I think the planet is probably more complicated than the single nerve cells I study and model. It is possible that we are at the beginning of a global emergency on climate change, but don’t know it yet because the computer models haven’t predicted it. But those models are now completely discredited and not because of a bad strategy, but because they aren’t sophisticated enough to be useful and helpfully predictive. They confirm that we may have a future problem, but they haven’t been able to predict the events of the last few years, particularly with respect to the melting of the polar ice caps and what this might do to sea levels and global temperatures.

Here are two examples of the failure of contemporary models. EXAMPLE 1: The ice of Antarctica is melting faster and by mechanisms that were not appreciated or included in models. This past February through March, the Wilkins Ice Shelf broke up and disappeared in a matter of a few weeks. This was not the first time that such a seismic event of ice breakup has occurred. Climatologists have incorporated into their models the assumption that the loss of ice would take place at the edges, where the ice meets the increasingly warmer ocean. But that is not what happens. Like the Wilkins Ice Shelf loss, the surface of the ice is melted during the day, with the water accumulating into pools and fissures that penetrate into the ice further back from the ice-ocean interface. At night, when this water freezes, it expands and puts pressure on the ice sheet to break up into smaller sections. So, instead of losing an ice shelf over hundreds if not thousands of years, as the edge model would have us believe, massive ice shelfs can be lost virtually overnight. No model ever had that mechanism included and it is one reason why we must question all the results of all the models.
Example 2: The acute focus of many climatologists has now been targeted to Greenland, which was once thought to be relatively free from short-term meltdown created by global climate change. But a group of researchers from Woods Hole Oceanographic Institute, working in Greenland earlier this year, watched a 3 kilometer (about 1.8 miles) wide lake suddenly disappear into a 1 kilometer fissure in the lake within 90 minutes. The flow of water necessary to drain the lake so quickly would be greater than the flow of water over Niagara Falls. The point behind this observation is that climate change can occur quickly, as if there might be a tipping point and that kind of climate behavior does not emerge from the models. There aren’t enough chaotic variables in the models that can spin the simulation into predicting short-term, highly non-linear catastrophes. If Greenland loses its ice, then water levels could be elevated by as much as 6 meters (~18 ft) and many cities would be under water. This could occur so rapidly that there would not be enough time to move inland in an orderly way and many people could either drown or starve to death. It would be very hard for any model to predict either of the illustrated events.

All climatologists are in a state of panic, because governments are relying on their data to formulate global climate change treaties and policies. The Intergovernmental Panel on Climate Change (IPCC) is a multinational organization that studies climate change patterns and provides governments with data that are used by them to formulate treaties, such as the Kyoto treaty (that the United States did not sign). Now European governments are going ahead with a new treaty and formulating it on models and data that we know are completely inaccurate. The models used so far underestimated the rising temperatures by at least a degree (2.5 vs 3.5 degree centigrade–a huge difference).

The treaty that is now under development will propose keeping the atmospheric carbon dioxide level below 450 ppm. This compares with pre-industrial levels of 280 ppm and the current level of 380 ppm. The assumption is that by allowing the carbon dioxide to get to 450 ppm, but no more, the earth will experience no more than a 2 degree C increase in temperature. But the modeling data that supports that conclusion is completely discredited and no one has a better model that is ready to give us better results or a more certain understanding of what we can expect.

A paper submitted to SCIENCE MAGAZINE by James Hansen of NASA has argued that if you look back 50 million years at a time when carbon dioxide levels were falling and reached a level of about 425 ppm, a level we are likely to see in a decade or two, that is about the time that Antarctica got its ice cap. This raises the possibility that the planet may have a tipping point near that level and by going above it, as future treaties are likely to allow and project, Antarctica might become ice free and if so, the projected rise in sea levels would be more like 60 meters or ~180 feet. While I wouldn’t start moving to the mountains just yet, we should all appreciate the high degree of uncertainty that we will live with for the rest of our lives about global climate change and recognize that we still know very little about the planet that we live on.

We started to devour the planet long before we ever tried to figure out how it works. Perhaps the planet is getting ready to devour us or many of us and do so faster than we think. It would of course be naive for anyone to assume near-term calamity threatening extinction of the human species. But progress on understanding the planet we live on is very likely to be so slow that we may not be able to keep up with the changing reality of the global climate change itself. In other words, we will continually be faced with studying a new planet every time one of the homeostatic mechanisms gets lost. The melting of the polar ice caps that we are witnessing before our eyes is roughly 10 to 50 years ahead of schedule. If a tipping point exists for polar ice caps and Greenland, then it seems almost certain that this planet cannot sustain the human population that it has now (6.5 billion). The exponential growth of the population ceased in the 20th century, so that we are expected to reach zero population growth sometime this century, at which time we may level off at 7-9 billion humans on our little planet. If some catastrophic future lies ahead of us, it is only too bad that nature can’t selectively pick out the Republican Party as a kind of trial balloon to see if their extrication can, all by itself, fix the lovely little blue planet we have gown fond of.

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