For everyone else it was the glaciers: for the Dutch it was the flooding. Last January errors in the work of the Intergovernmental Panel on Climate Change (IPCC) hit the headlines. The chapter on Asia in the report by the IPC's second working group, charged with looking at the impact of climate change and adapting to it, mistakenly claimed that the Himalayan glaciers would be gone by 2035. This contradicted some reasonably basic physics, had not been predicted by the glacier specialists in the first working group (which deals with the natural science of past and future climate change) and was unsupported by any evidence. There was a report from the 1990s which said something similar about all the world's non-polar glaciers, but it gave the date as 2350. Then there was a crucial typo and some shoddy referencing. Nevertheless the IPCC’s chair, Rajendra Pachauri, had lashed out at people bringing the criticism up, accusing them of "voodoo science". He then had to eat his words, and set up, with Ban Ki-moon, a panel to look into ways the IPCC might be improved.A report from a British panel prompted the New York Times to declare that climate alarmist scientists had been "cleared," despite the fact that it "was the University of East Anglia that commissioned a paid investigation to uncover corruption and (un)scientific malfeasance at -- wait for it! -- the University of East Anglia's own Climate Research Unit!"
Inspired by this to look for other errors, a journalist for a Dutch newspaper spotted that the chapter on Europe gave a figure for the area of the Netherlands below sea level that was much too large. The area at risk of flooding by the sea had been conflated with that at risk of flooding by the Rhine and the Meuse rivers. . .
The auditors found one new error which they deemed major: a statement about the frequency of turbulence in South African fishing waters which had been translated directly into a statement about the productivity of the fisheries. The IPCC has indicated it will produce an erratum for this, and for a number of other errors all concerned deemed minor. But the PBL also identified seven statements, which, while not errors, it thought were deserving of comment (for which read criticism).
Perhaps the most striking relates to Africa. The table in the summary for policymakers reads: "By 2020, in some countries, yields from rain-fed agriculture could be reduced by up to 50%." The evidence on which this is based says only that yields during years in which there are droughts could be reduced by 50%. Furthermore, the relevant reference applies only for Morocco--and it cites as its source an earlier paper that the PBL says no one, including the IPCC authors, now seems able to find.
Other criticisms turn on a tendency to generalise. Research showing decreased yields of millet, groundnuts and cowpeas in Niger becomes a claim that crop yields are decreasing in the Sahel, the strip that separates the Sahara from the savannah in Africa, rather than that the yields of some crops are decreasing in some parts of the Sahel. The results of research on cattle in Argentina are applied to livestock (which would include pigs, chickens, llamas and the rest) throughout South America. The expert authors do not provide a compelling reason for their claim that fresh water availability will decline overall in south, east and southeast Asia, or that the balance of climate-related effects on the health of Europeans will be negative.
Which shows the degree (hah!) to which lefties remain wedded to warming.