Scientists have been responding to claims that if they were unable to predict the bad weather how can they predict climate change over the next century?
Scientists have been responding to claims that if they were unable, a few weeks ago, to accurately predict the severe weather that has hit Britain over the past few days, how are they able to accurately predict climate change over the course of the next century?
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Speaking on last night’s Newsnight, Dr Patrick McSharry, research scientist at the Smith School at Oxford University, explained that there is a “big difference” between short-term weather forecasts and long range climate forecasting. He said:
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“If you look at the actual scientific details of what’s been attempted to be calculated there is a huge difference. Before someone generates a forecast they have to validate the model, they have to make sure it adds up to being able to predict the historical events that have gone beforehand and if it’s able to do that then you have some confidence that it will actually work into the future.”
Keith Groves, Director of Operations at the Met Office, added that global warming can only have come from carbon dioxide:
“We do validate our climate models. To actually reproduce the change in temperature that we’ve seen in the last 100 years, the only way you can do that is by adding carbon dioxide into the model, so we have real confidence in the skill of our climate model to replicate the global climate as we move forward.
“That’s completely different to trying to forecast the variability on one month or two month or a season ahead. It’s a completely different application of the science.“
30 Responses to “Long range forecasting is accurate and CO2 does cause global warming”
hmmm
Anthony Zacharzewski, yes, my comment was flippant and simplistic. Apologies. I think you will find, though, that much of the failure of risk management was down to poor understanding of the assumptions, implications, global topology, and numerical stability of models. Of course, there may well have been underlying regulatory and policy failures, but I would venture to suggest that a significant fraction of the practical failure originated this way.
Don’t put scientists on a pedestal, though, unless they really deserve it. Go ahead and sing effusive songs about Debakey, if you like. Praise Dirac to the skies. Which climate scientist will you put in the same league?
“Highly advanced modelling software” in practice tends to be MATLAB. It’s pretty good but it is off-the-shelf, and definitely doesn’t take a genius to operate it. Of course, programming supercomputers efficiently is still a fairly rare skill, but the most widespread use tends to be cluster applications, and most scientists these days know at least the rudimentary philosophy of multithreaded code. I doubt climate scientists have a huge demand for packages to deal with arbitrary precision arithmetic, but you can use any number of free libraries to do so. I personally have a preference for BigNum but YMMV. Almost everyone doing numerical work knows how to do Monte Carlo simulations. Most know basic speedup algorithms, though they generally aren’t necessary as surprisingly little science is actually computationally intensive.
I think you will find the basic techniques used for climate modelling, financial modelling, or any kind of numerical modelling are fairly standard. It is very legitimate to compare them. PDEs don’t care what their purpose is; just whether they are elliptic, hyperbolic or parabolic. A Hessenberg matrix doesn’t care whether it’s being used to price CDOs or to calculate currents.
Collecting data? Well, it is hard for me to judge experimental scientists, as I am have never been one. Speaking generally, measurement requires patience and dedication rather than innovation and genius though. I am glad there are people willing to do this work in dangerous conditions, though.
I am categorically NOT saying the climate science models are bad, just idly wondering on a day off from work what they said 20 years ago. I’m sure it was perfectly valid and they spelt out their assumptions very clearly. I could just go ahead and look up the journal articles, but I figure, seeing as this is an evidence-based blog, someone will know the references offhand.
Oxford Kevin, yes, both the RS and NAS wholeheartedly support research in climate change, and as an issue of important public policy, take an active role in trying to disseminate the science, as you would fully expect them to. I have respect for climate scientists – I have respect for all scientists. My main point was that I just don’t see any true genius working in the field though.
Oxford Kevin
Do those societies just support climate research or have they come out with statements backing the climate scientists position on AGW?
Does the Royal Society feel so strongly about this issue that they have put out a guide on climate change controversies?
hmmm
Oxford Kevin, please stop being so paranoid. I am not a climate change sceptic, in the conventional sense. I just think that “evidence” should mean “evidence”, not things which sound like “evidence”. I support the work of the Royal Society in promoting scientific literacy, and scientific outreach programmes, in all their forms, including the excellent public dissemination work on climate science. I have often done outreach work in my own field, and it is refreshing to do so.
Are you really saying it is unacceptable to think that physics professors are more intelligent, on average, than climate science professors?
Oxford Kevin
Economic modelling has for too long been dominated by the theories of the Chicago School of economics which posits that we all behave as rational actors when making financial decisions. When in fact human behaviour has lots of elements of herd like behaviour, we put too much weight on recent data, and discount things that happened long ago. This has not just had impacts in the modelling but also in the stripping of regulations relating to the financial sector which were introduced in the thirties. Making comparisons between economic models and ones based on the physics and chemistry as best as we understand them is not really valid.
Oxford Kevin
Could you please answer my question in relation to the two societies you mentioned about whether they support the climate scientists position on AGW or not and not give a politicians response as you did?