Thanks to Réaumur I was alerted to this. It is a transcript from the BBC World at One – 27/09/2013 (starts at 7:28)
(BBC presenter) The last time the scientists on the Intergovernmental Panel on Climate Change, the IPCC, reported, they said it was very likely that man’s actions were the principle cause of the warming planet. This morning six years on, they say it’s extremely likely. It’s a simple phrase but it follows a big program of work involving authors in thirty nine countries. As an official body there was quite a bit of haggling in the hours preceding publication though, a process in which government sponsored scientists have to agree every phrase.
It’s then down to the governments to use the findings as a basis for a new treaty for tackling climate change. The energy and climate change secretary Ed Davey says it will strengthen the UK government’s demand for tougher international targets to reduce carbon emissions.
(Ed Davey) This piece of evidence that we are seeing from Stockholm is probably the most robust, rigourous, most peer reviewed piece of science in human history. I think it has put the question of whether climate change is happening beyond doubt. We have got to stop debating this issue as if we are some members of the flat earth society and get on and act.”
Even some of those who support the panel’s findings though are critical about the way it operates. Lord Stern who wrote a report for the last government on the economic effects of climate change has complained about filtering and haggling leading to bland conclusions.
That is nothing compared to the dissatisfaction felt by Bob Carter. An Australian geologist and Oceanographer he accuse the IPCC of being unscientific in its approach. He has contributed to an alternative non-governmental group calling itself the NIPCC.
(Bob Carter) The difference between between the two reports is this. That the IPCC has an idea. It is not actually their idea it was why they were set up. They were told to go away and consider the business, not of climate change in the round, but of climate change caused by human greenhouse gas emissions. So what it does it that it goes out and looks for evidence, for humans having a dangerous impact on climate. Now real science doesn’t work that way.
Now as you probably know science proceeds in general by setting up what is called a null hypothesis which is the simplest hypothesis. And that is: we look out the window and we see everyday change in the weather and in the longer term the climate. The distribution and patterns of nesting and flowering and so on of animals and plants. So we know the real world is variable the whole time.
The null hypothesis therefore is: that those changes we observe are due to natural variation. And the NIPCC report tries to invalidate that hypothesis. And the really interesting thing is that after looking at several thousand papers just like the IPCC, we come to the opposite conclusion. One of our conclusions is that climate has always changed and it always will. There is nothing unusual about the modern magnitudes or rates of change: of temperature; of ice-volume; of sea-level, or of extreme weather events.
The IPCC said today that having previously said that it thought it was very likely that man was responsible for global warming, the activity of man being the main reason for global warming. It now says it is extremely likely, 95% certain [delusion] that is a very different conclusion to yours.
The problem with what you just said to me about 95% probability is that it is hocus pocus science. In science the phrase 70% probable or 90% probable had definite meanings. They imply controlled trials, they imply numerical quantitative information objectively assessed. If you ask the IPCC they will tell you that when they use the term 95% probable it is based on the expert opinion of a group of people gathered around a table. It is completely wrong to use probability terminology to describe what is albeit an expert opinion. Continue reading →
