The Intergovernmental Panel on Climate Change has now concluded its fifth assessment on the state of knowledge about global warming and how to contain its risks, by releasing its Synthesis Report. The Synthesis Report is an attempt to draw together and summarise the vast amount of material in the other three sections of the Fifth Assessment, which were released over the space of the last 12 months covering:
- Physical science – which looks at how rising greenhouse gas emissions are likely to affect our climate including global temperature, precipitation, sea level and also ocean acidity.
- Impacts – how these changes in climate will affect humans as well as the natural world.
- Mitigation – how could we reduce greenhouse gas emissions.
Climate Spectator has extensively reported on each of these component sections of the Fifth Assessment. So rather than just summarising a report that is meant to be a summary in itself, we thought now might be a good point in time to provide a recap of what we’ve learnt about why the climate sceptics are wrong, via our reportage on three heroes of the climate science denialist movement.
Hero 1 – Maurice Newman
Prime Minister Tony Abbott’s adviser on matters of business, Maurice Newman has suggested the Intergovernmental Panel on Climate Change is really a plot for socialists to impose a one-world government intent on mass wealth redistribution (he said it here).
According to him – and an array of mass conspiracy theorists – the smoking gun that exposes their plot is that global warming has apparently stopped since 1998 and, Newman warns us, we may even be about to descend into a global war driven by global cooling (See: We’re ill-prepared if the iceman cometh).
But before you go on a shopping spree to stockpile thermals, winter woollies, guns and ammunition, can I suggest you read IPCC – a primer for conspiracy theorists. This article helps to explain that the IPCC is not some monolithic standing army of United Nations employees, but more a process whereby a disparate group of researchers from a wide array of universities and other research institutions across many countries come together to co-operate in summarising the research literature on climate change.
Once you’ve reassured yourself there’s no need to revive Joseph McCarthy from the dead to investigate the IPCC, you might then want to read about whether global warming really has stopped. The article IPCC rebuff to the global warming sceptics explains that even if the rate of surface temperature rise has slowed in the last decade (it is still the hottest decade on the instrumental record, by the way, and the last 30 years are likely the hottest 30-year period in the last 1400 years) this misses the bigger picture of heat absorbed by the ocean. In the end this slowing in the rate of temperature rise is likely to be temporary. If you’re wondering what has been driving extra heat into the ocean then you could also read Another scientific dagger to the deniers.
Hero 2 – Bjorn Lomborg
OK, so maybe you aren’t one for conspiracy theories, you’re prepared to accept expert advice that global warming is real from the Academies of Science and the meteorological agencies of the United States, the UK, Australia, Germany, Italy, Canada, France… okay, I’ll stop there.
But according to Lomborg, while global warming is real, it’s nothing much to worry about and everyone’s just being alarmist. Lomborg said: “The IPCC report is out. It is moderate – global warming is real, but not end-of-the-world … The report shows similar temperature rises to earlier reports, at about 1 to 3.7 degrees by the end of the century ... The IPCC’s moderate projections clearly contradict alarmist rhetoric, such as the recurring claims from activists of temperature rise of more than 5 degrees.”
As we explained in Lomborg misleads on IPCC, he was rather cute in this little take-out from the IPCC report. If we took Lomborg’s own advice about what government’s should do to constrain global emissions (pretty much nothing), then the IPCC suggests we are on track to a likely range of temperature rise that skirts 5 degrees above pre-industrial temperatures and gives us a greater than 50 per cent chance of exceeding 3.7 degrees. We also explained that Lomborg plays another trick with the IPCC’s work by focusing on the average estimate of temperature rise from our carbon emissions, and ignoring the reasonable probability we face of catastrophic outcomes. We also showed how work beyond that of the IPCC helps to better explain some of the risks we are running. For example, the chart below from the International Energy Agency illustrates that based on current government policies at the time (red line) we face a very high probability of exceeding 5 degrees temperature rise by 2200.
Figure 1: Projections of greenhouse gas concentrations and temperature rise probabilities for different policy paths
Source: International Energy Agency – World Energy Outlook 2012
Hero 3 – Richard Tol
Richard Tol, an active participant in the IPCC process, grabbed headlines this year when he publicly withdrew his name from the Summary for Policy Makers chapter of Fifth Assessment’s Climate Change Impacts Report. This was because he claimed it was “alarmist” and not an accurate reflection of the underlying research in the Impacts report.
I suggested the complete opposite in the article The limits to climate change adaptation. This went through specific findings within the underlying chapters of the Impacts Report to show that we are running a very serious risk of climate changes that humanity would struggle to adapt to. We then took a more in-depth look at Richard Tol’s own work in The Lomborg man behind the IPCC mutiny. It turns out that the IPCC had to subsequently correct some of Richard Tol’s contributions to the Impacts Report after errors were found in research he published in the Journal of Economic Perspectives which acted to downplay the negative consequences of global warming.