by OWEN MARTIN
So tonight there was a presentation in Trinity College by Tim Palmer of Oxford University. First, the good parts - he tried to show both sides of view and addressed some of the claims made by climate "skeptics". On the bad side, as usual with these events, there was very little time for questions at the end. Here is just some bullet points and notes I made on the lecture :
• He gave a counter argument to some of the claims made by Matt Ridley in his October lecture to GWPF. However, no mention of greening i.e the increased plant growth observed around the planet. This to me was Ridley's ace card so I was surprised that he didn't take that on (or maybe not surprised).
• He explained quite well how using data over short timescales can be misleading. I agree with this however his own temperature graph (from NASA) started in the late 1800s. This is an extremely short time range to be basing any theory on. We didn't have weather stations before 1850 but we know (thanks to geologists) about the Little Ice Age. The Little Ice Age ended around 1850 when CO2 emissions were a tiny fraction of what they are now. We started coming out of the LIA around 1720. This data should be factored in to put climate change in perspective.
• He explained how the climate system is complex, again I agree, and that it is a chaotic system. When you introduce man made CO2, the system tends to become less chaotic and you end up with warming. So if you start with this theory, which looks plausible, then you need to fit the facts into this theory. This happens with NASA graphs which are based on adjusted data. You need to take the cooling in the 70s out and you need to reduce the warming in the 40s. You also need to ignore the Atlantic Multidecadal Oscillation (and PDO) which has a well established positive / negative cycle. This question was posed at the end but I cant even remember the answer. Again, these issues need to be addressed but were not considered as the original "greenhouse gas" theory was infallible.
• Palmer explained the clouds issue really well - we don't know whether they lead to cooling or warming.
• No mention was made of solar irradiance. Again, there was a question on this but an all too brief answer.
• If global warming is dangerous to humans today then in a period of natural cooling, global warming would be advantageous to humans (as it would reduce cooling). Like greening, the upsides were not considered.
• A question was asked at the end asking for evidence that CO2 remains in the atmosphere for 50 years or more. Palmer didn't have any evidence for that claim yet the claim was made as if it were fact.