Shaun Lovejoy thinks so. Shaun is a professor of physics at McGill University, so he’s a Physicist, and therefore should know what he is talking about, right?
Well, this month he got an article published in Climate Dynamics in which he reports that there is a “greater than 99.9% confidence that climate change is happening because of greenhouse gas emissions related to human activities.” His research was based on a probability analysis of temperature data going back to 1500’s.
In the last 24 hours, I’ve been watching this story rise from being broken on lesser well visited websites, then up the ranks until well, I thought it would have appeared on the major media outlets – but I’m sure it will by the time you read this! (I’ll update when I see it…) Nothing like a scientist publishing something so damning towards humanity in a scientific journal – it must be right, right???
But, although I have never questioned the fact the planet is warming, I do have a lot of questions regarding the burning of fossil fuels being the only cause of any warming in the last century and a half. So someone stating they are 99.9% confidant, based on temperatures records going back to the 1500’s just brings out the big skeptic in me – not skeptic about the planet warming, but skeptic about humans being the sole and only cause!
For starters, we don’t have any consistent temperature record for the planet going back to the 1500’s. None. In fact, it would appear that the scientists didn’t even particularly agree on how to measure temperature until the 1700’s and each time you convert the temperature, there is probably some margin of error carried with it. So if scientists were only just beginning to wrestle with measuring temperatures in the 1700’s, then it very unlikely there are any good records from the 1500’s, and there certainly no consistent effort to measure the temperature all over the planet prior to the 1800’s or 1900’s. That’s a pretty poor temperature foundation to have absolute confidence in!
Heck, even now we still don’t have uniform coverage of weather stations across the planet – but I’m willing to bet, we have a LOT better coverage than we did in the 1500’s or the even the 1700s’s! (Interesting.. reading the blurb from the above links, it would appear the world didn’t even start acting globally and plugging the temperature gaps until the 1970’s…)
Furthermore, have you ever tried to find the raw temperature date today? You can’t. It’s all statistically manipulated to moderate for variables (see below – there is so much information on this…) – some might be ‘cleaner’ than other’s, but its just about all tweaked for variables like area of influence between weather stations, the changing landscape and its albedo etc. In addition, which variables are moderated for will vary with who is moderating the raw temperature data. And then of course, most of the climate models are based on these statistically ‘smoothed’ temperature data sets. The two biggest global climate data sets come from NOAA (US) and the MetOffice (UK) – who both use slightly different methods, and upon which, many climate models are built on.
Anyway, I digress… To get back to the point, what temperature data sets was Shaun Lovejoy looking at to give him 99.9% confidence? To find out, I went to Climate Dynamics, where I discovered I was sort of locked out because they wanted a staggering US$39.95 to view one article! (But it would apparently cost me between $6,000 and $7,200 for a years subscription, so I guess a bargain in comparison?!). I swear, the digitising of journals has done NOTHING for information transparency because once I could wonder into university libraries (paid for by tax dollars) and look at any of these journals for free, but now, I have to pay MORE to view a single article than I would to probably pay for a book on the subject. However, I’ll save that rant for another day…
But you and I, the poor and uninformed public who can’t get to the source of information without hurting our pockets, could at least get a glimpse at the paper by reading the abstract. And for the most part, it is completely uninformative and for the layman, eye-glazing – more so as it is apparent it is based on statistical manipulation of data. Yay. Statistically manipulated statistical data. How many more errors can be introduced into this??? However, even eye-glazing abstracts can be generally understood by the population at large if they can see the data that the abstract is based on. Which isn’t happening for this article…
Fortunately, others do work at Universities or bodies with subscriptions to such journals, and are happy to provide us, the locked out public, with an insight into what gave Shaun Lovejoy such confidence… Well, the first thing one learns is that 99.9% confidence means that it is so accurate, it is virtually unquestionable. Given this level of confidence is based on statistically manipulated temperature data, I don’t doubt someone could run the numbers again using Shaun Lovejoy’s data and formulae and get the same answer. But what if they decided to use different temperature data? What if someone didn’t like whatever was used for temperatures in the 1500’s and substituted some other temperature variable? They could get wildly different answers from more confidant (if possible) to less confidant.
Well, as I said above, I’m not a statistician, but I for one do not doubt the planet is warming, and none of these models to date have informed us as to why the planet warmed a good 6oC before the Industrial Age without humankind having really any input to that (and probably none to explain why the last ice age ended – but it definitely wasn’t because of humans burning excessive amounts of coal and trees!), and why we should be solely responsible for the last 1.5oC. Would I be willing to say that I have 99.9% confidence in the data on hand to say man hadn’t warmed the planet at all? No. But by the same token, I also don’t have 99.9% confidence that we are the only contributor either! A statistical analysis I cannot easily access based on statistically manipulated temperature data does NOTHING to improve my confidence in man’s contribution. My money is on we have contributed to warming only and how much is still up for debate, despite Shaun Lovejoy’s confidence in his statistical analysis!
What do you think? Feel free to leave your comments below.