The latest climate science from the IPCC and some early reactions

The summary report for policy makers from the latest IPCC Working Group 1 report was released a few hours ago, at 10:00 am this morning Stockholm time.  For the last five days the IPCC has been meeting to consider and finalise the draft report.  By all accounts it was a mammoth session, with participants working around the clock.  If nothing else, it shows that all the participants took the summary report very seriously.

I watched the live telecast and have skimmed the Summary for Policy Makers.  It's only 36 pages from beginning to the figures and tables at the end.

David Rose asks an "ill-posed question", from a scientific point of view

During the telecast, tabloid writer David Rose asked a question and was told by Michel Jarraud of the WMO that from a scientific point of view it was "an ill-posed question" based on a misunderstanding of how models work.  Good for Michel Jarraud!

How much more can we burn?

One figure that stood out was a plot of temperature against cumulative CO2 and cumulative carbon.  I was going to include the full caption but it's long.  Scientists don't make things simple to follow, do they.  You can read the caption at the top of page SPM-20 here. Click image for larger version.

Figure SPM.10: Global mean surface temperature increase as a function of cumulative total global CO2 emissions from various lines of evidence. 

The thing I like is that it shows our choices in terms of a carbon budget.  If we are happy to send humanity to a dreadful future we can decide to keep burning carbon.  If we want to opt to give future generations a reasonable hope of continuing civilisation, then we will set a budget limit.  From what I can work out that limit will need to be at around 800 Gt of carbon (GtC is shown on the bottom horizontal scale).  I've overlaid lines showing the 2 degree mark and the 800 Gt mark.  The report states:

Limiting the warming caused by anthropogenic CO2 emissions alone with a probability of >33%, >50%, and >66% to less than 2°C since the period 1861–188022, will require cumulative CO2 emissions from all anthropogenic sources to stay between 0 and about 1560 GtC, 0 and about 1210 GtC, and 0 and about 1000 GtC since that period respectively23. These upper amounts are reduced to about 880 GtC, 840 GtC, and 800 GtC respectively, when accounting for non-CO2 forcings as in RCP2.6. An amount of 531 [446 to 616] GtC, was already emitted by 2011. {12.5}

I think that translates to - don't burn any more than 800 Gt of carbon if you want to leave any sort of future for humankind.

IPCC Headline Statements

There are the nineteen headline statements from the approved Summary for Policy Makers (my bold italics).  It seems to me that they are more forceful than were previous reports.  I won't list the lot - you can read them all here in a separate document or as part of the SPM itself.  I'll just list a few of them:

• Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, sea level has risen, and the concentrations of greenhouse gases have increased. 
• Ocean warming dominates the increase in energy stored in the climate system, accounting for more than 90% of the energy accumulated between 1971 and 2010 (high confidence). It is virtually certain that the upper ocean (0−700 m) warmed from 1971 to 2010, and it likely warmed between the 1870s and 1971. 
• Over the last two decades, the Greenland and Antarctic ice sheets have been losing mass, glaciers have continued to shrink almost worldwide, and Arctic sea ice and Northern Hemisphere spring snow cover have continued to decrease in extent (high confidence). 
• The atmospheric concentrations of carbon dioxide (CO2), methane, and nitrous oxide have increased to levels unprecedented in at least the last 800,000 years. CO2 concentrations have increased by 40% since pre-industrial times, primarily from fossil fuel emissions and secondarily from net land use change emissions. The ocean has absorbed about 30% of the emitted anthropogenic carbon dioxide, causing ocean acidification. 
• Human influence on the climate system is clear. This is evident from the increasing greenhouse gas concentrations in the atmosphere, positive radiative forcing, observed warming, and understanding of the climate system. 
• Climate models have improved since the AR4. Models reproduce observed continental-scale surface temperature patterns and trends over many decades, including the more rapid warming since the mid-20th century and the cooling immediately following large volcanic eruptions (very high confidence). 
• Human influence has been detected in warming of the atmosphere and the ocean, in changes in the global water cycle, in reductions in snow and ice, in global mean sea level rise, and in changes in some climate extremes. This evidence for human influence has grown since AR4. It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century. 
• Continued emissions of greenhouse gases will cause further warming and changes in all components of the climate system. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions. 
• Changes in the global water cycle in response to the warming over the 21st century will not be uniform. The contrast in precipitation between wet and dry regions and between wet and dry seasons will increase, although there may be regional exceptions. 
• The global ocean will continue to warm during the 21st century. Heat will penetrate from the surface to the deep ocean and affect ocean circulation. 
• Cumulative emissions of CO2 largely determine global mean surface warming by the late 21st century and beyond. Most aspects of climate change will persist for many centuries even if emissions of CO2 are stopped. This represents a substantial multi-century climate change commitment created by past, present and future emissions of CO2.

What the papers are saying

I went to see what the papers were saying.  The Telegraph, where denier blogger James Delingpole has a large if mainly illiterate following, wrote a fairly straight report with a couple of interesting quotes:

One delegate told the Telegraph on Thursday night: "The good news is that the Saudis are not objecting to every word like used to happen [at previous meetings].

"It is pretty tame compared to the early years of the IPCC when you used to have a real scrum between people like the Chinese, who could be quite difficult. There is no-one in there saying climate change isn't real."...

...Ed Davey, the Energy and Climate Change Secretary, said solutions to the problem of man-made greenhouse gases accumulating in the atmosphere “must be set in motion today.”
He said: “The risks and costs of doing nothing today are so great, only a deeply irresponsible government would be so negligent.

“Without urgent action to cut greenhouse gas emissions this warming will continue, with potentially dangerous impacts upon our societies and economy.”

Sky News Australia wrote a straight report with the headline: Man-made warming 'extremely likely'

Australia's Sydney Morning Herald featured a strong editorial:

The new Intergovernmental Panel on Climate Change report should be a game-changer in how Australia tackles global warming. But it won't be - not without strong leadership from Prime Minister Tony Abbott.

Future generations will look back, see the clear evidence of human-induced climate change in this and previous IPCC reports and wonder why more wasn't done sooner to tackle the problem? They will look at the safety-first approach of the Howard Coalition government on, say, terrorism, where substantial policy, investment and cultural change was implemented to minimise that risk.

Why, they will ask, does this Abbott Coalition government at best play down the risk of global warming and at worst deny it to protect vested interests and reinforce the ideological groupthink among its cheer squad?

Read the full SMH editorial here.


The Washington Post wrote a fairly straight article, with some quotes from leaders in the USA inexplicably next to a couple from anti-science blogger, Anthony Watts, presumably to show up just what clowns the fake sceptics are.  A short excerpt (my bold italics):

In the United States, officials reacted favorably to the report. Secretary of State John Kerry said “climate change is real,” happening now, and that the United States is determined to be a leader in curbing emissions.

Sen. Barbara Boxer (D-Calif.), chair of the Committee on Environment and Public Works, called the report a landmark and said it underscores the administration’s recent efforts. “I will do everything in my power to support the administration in their efforts to address the dangerous impacts of climate disruption,” Boxer said.

Frances Beinecke, president of the Natural Resources Defense Council, an environmental advocacy group, called the report “a warning bell to the world.” She said the impact are fierce wildfires, drought, floods and storms that will only get worse with delay. “The science is clear: We are altering the climate,” Beinecke said.

But deniers of climate change dismissed the report. Anthony Watts, a former television meteorologist who writes the blog WattsUpWithThat, called it “comical at best.”

Read the full Washington Post article here.

There's a miscellaneous collection of news items, newspaper blogs and editorials here on Google news.  Mainstream media is doing straight reporting.  I'd say if you want to read what science deniers are saying you'll have to go to their blogs, because they don't seem to be getting much airplay in the news.

What the science deniers are saying

Anthony Watts on his blog WUWT (archived here) says his first reaction was:

That IPCC had a golden opportunity, and blew it due to being unable to adapt to reality.

He didn't say what he thought the "golden opportunity" was or how the IPCC "blew it", only why.

Anthony promised a "bullet point collection" of reactions as they come in, but he left out the bullet points.  There is not a dot to be seen at WUWT.

As for reactions, Anthony did report that Judith Curry went looking through the summary report for her favourite "uncertainty".  Going by what I've read she will be certain to have found less uncertainty than was in previous IPCC reports.  Therefore it is extremely likely that Judith Curry won't be happy (high confidence).

The reaction from the rest of what Anthony has collated is predictable and boring.  The usual "I don't believe it" and "all the world's experts are wrong" mixed in with mostly non-specific grumbles and moans.

From the WUWT comments

The comments are archived here with Anthony Watts bullet-less bullet points.

Mike Bromley the Kurd says:

September 27, 2013 at 7:17 am
They just keep running for the shelter of their old pal CO2. It’s tiresome.

What is BBC Radio 4 doing talking to Bob Carter? son of mulder says:

September 27, 2013 at 5:25 am
Just heard Prof Bob Carter on BBC Radio4 World at One. Brilliant interview putting a sound sceptical perspective on the IPCC report. Well worth a listen again when it is available.

Professional science disinformer, Ross McKitrick,  is running out of gigs and is commenting on WUWT.  He also hasn't read much climate science but thinks he's being "clever" instead of wrong as usual - he says:

September 27, 2013 at 5:32 am
SPM in a nutshell: Since we started in 1990 we were right about the Arctic, wrong about the Antarctic, wrong about the tropical troposphere, wrong about the surface, wrong about hurricanes, wrong about the Himalayas, wrong about sensitivity, clueless on clouds and useless on regional trends. And on that basis we’re 95% confident we’re right.

Bill Illis resides on different planet, or so he says:

September 27, 2013 at 5:35 am
We should just be pointing out the errors now. There is no point discussing the virtual world the IPCC is talking about – they are not talking about the real planet Earth, but some virtual world, planet Nibiru in a climate model.
———-
One major graphic is clearly wrong. The observed change in temperature from 1901 to 2012 – figure SPM.1 (b), particularly the Oceans part. There has been no warming in the central Pacific but it is shown as +0.4C or so in the graphic (large parts of it not shown despite there being a large number of measurements in this region covering the whole period). There has been no warming in the far southern ocean (again it is missing despite a large number of ships being there over the whole period – including whaling ships in the early part of the 20th century). Other areas have no warming over this period yet the entire Ocean area is shown as having warmed. Clearly the Figure is meant to show warming everywhere yet that is not correct.
———–
The graphic showing observed change in temperature relative to the climate models shown in earlier drafts is not included in the report anymore.

Here is the chart to which Bill refers:

Bill provides no evidence of why he thinks the chart is wrong.  I'm going to go with the science rather than a WUWT regular.

Peter Ward is complaining that people are listening to scientific experts instead of anti-science bloggers:

September 27, 2013 at 5:35 am
In the MSM (BBC, CNN, etc) the IPCC report is being portrayed as the gospel truth on climate change. For example the CNN summary is “The world’s getting hotter, the sea’s rising and there’s increasing evidence neither are naturally occurring phenomena”. I think it’s fair to say that the MSM are onside with the warmists. The online debate is not reaching the consciousness of the general public.

Steve C says he refuses to look at the evidence, fearing being shaken and stirred:

September 27, 2013 at 5:39 am
The BBC are all over it today, of course. Fawning interviews with the IPCC crowd to spread their political message and – a new development! – the occasional few words from the likes of Bob Carter, now being allowed as the “minority view” to give the impression of balance. Overall, exactly as you’d expect from “The World’s Most Respected Broadcaster” (© BBC): junk reporting of junk politics.

I, meanwhile, remain unshaken and unstirred. Nobody has yet produced any evidence (that I’ve been able to find) to suggest that humanity has had any effect, still less a “catastrophic” one, on the world’s weather systems, therefore the null hypothesis holds. Still waiting, guys. Show me how evil we are, rather than how evil you are.

Robert W Turner is in a world of his own and says:

September 27, 2013 at 8:06 am
The sad part is most of the policy makers that will read this are going to fall for it. How long can this lie last and will anyone be held accountable when the jig is up?