Wednesday, 18 March 2015

Climate Change Debate Part III: Looking At The Science of Climate Change

Next week, in the final part of the series, I will undertake a full a cost-benefit analysis, looking at whether our long term problems are serious or not, and whether as our increased scientific, market and technological innovations continue they will render this whole climate change business a mere temporary red herring.

But before I do this, it is worth asking whether the green's interpretation of climate change science suffers from biases or intellectual skews. The indicators are that it does, and even that there are some pretty squalid distortions taking place. Greenpeace tell us that:

"The impacts of climate change are already being felt. Average global temperatures have risen every decade since the 1970s, and the 10 warmest years on record have all occurred since 1997".

This is true, but not necessarily compelling. Temperatures come in ups and downs. Measuring a few years since the 1970s just won't do. Below is a much more comprehensive set of data - it's a graph that shows global temperatures over the past 250,000 years:
Below is another graph - and this one goes even further - it shows global temperatures over the past 500 million years:



If you look carefully at both graphs, you'll see something interesting - we may be in a warm period, and quite a long one at that, but we are not in unprecedented territory - the planet has had similar peaks in the past. As you can see from the first graph, even the current warm period began several thousand years before the Industrial Revolution (the prior cooling period was down to an ice age). Given the foregoing observations, it's going to take quite a bit more than simply stating "We are in a current warm period" to show that this warm period is uniquely different to the others to the extent that we are the primary causers of a global catastrophe that needs mitigating by the green's preventative actions. The graphs show us that future scientific predictions should be done with humility. But even if scientists can confidently make forecasts about future global temperatures (it is thought that in the next 100 years global temperatures should increase from somewhere between 2-5%), such forecasts should come with some caveats.

Some scientists argue that climate modelling should be trusted because it is specific and can point to physical laws that are currently observable and constant. Alas, this is only half-true - but even if it were wholly true, that still does not justify such confidence that the green policies are the right ones. Just because a model relies on physical laws doesn't mean it has far teaching predictability. The weather relies on physical laws, but it does not have far reaching predictability. The predictions are relatively short-term; and in issues surrounding the perturbations of the environment short-term predictions are not very reliable antecedents for long-term outcomes.

Every day up until now 25 year old Julie has had eyesight good enough that she does not need glasses. She may justifiably predict that she won't in all likelihood need glasses in the next few days, nor weeks, nor maybe even months. But if she used those extrapolations to predict that she won't need glasses by the time she is 70, we would say that her short-term indicators are bad indicators for the future 45 years henceforward. Short-term climate change science suffers from the same problem. Trying to rely on long term predictions by extrapolating current patterns would be a bit like a man from another planet visiting earth for the first time in January and measuring the temperature in Trafalgar Square every day from January 1st through to August the 1st (increasing over the months from freezing up to 28°), and hypothesising that by December the temperature in Trafalgar Square will be 40°. 

Furthermore, merely focusing on the physics is not helping the green’s cause. No one disputes that the underlying physics behind any putative climate changes gives us empirical objects of study - and few deny that changes will occur. But the issue has never been about that - it has always been about how humans will respond to those changes.

Greens seem to have this faux-idealism that when it comes to temperature the world has some kind of objective optimality. It does not - some places benefit from higher temperatures, some from lower - but more than that - temperatures change over the centuries, and humans adapt to them - there is no optimal design for us. If there is no optimal design then this green metric of idealism that they use as a stick with which to beat us is misjudged. We cannot be castigated for contributing to the wrong kinds of temperature if there is no right temperature.

Yes it may be true that climate change is in some parts anthropogenic, but most of what we’ve done industrially and technologically has been to the huge benefit of the human race, not least in the way in which the industrial revolution and consequent progression-explosion of the past 200 years has increased life expectancy, prosperity, well-being, knowledge, and the many other qualities that benefit the human race. Don’t forget that our global emissions in the past century have been part of the very same scientific and industrial advancements that have facilitated this human progression. To criticise our innovations as being environmentally detrimental is a bit like criticising a vegetable patch for ruining perfectly good soil, or criticising medicine for ruining perfectly good plants.
For part one of this series - Climate Change Debate Part I: Confusion Between Risk & Uncertainty click here -

For part two of this series - Climate Change Debate Part II: Why We Don't Owe Future Generations As Much As We Think click here.