Neven, 500 congratulations for your brilliant blog(http://neven1.typepad.com/blog/ - for those reading this on twitter)

2.2 million square kilometres. If the estimate required is for average sea ice in September it might be a bit higher but I'm going lower than most because 1. Piomas volume is dropping and I have suspect that Piomas is beginning to estimate slightly higher figures than it used to. 2. Much of the ice is in a position which will melt more easily. (NOSEDIVE! on DOSBAT) 3. Rotten ice. Reinforced by reports of algal blooms. 4. The cracks in the ice. 5. More warm water coming in from the south. 6. More mixing of lower and warmer salty layers with surface water. 7. Tamino's statistical predictions set a target before most of the above are considered. 8. Methane's lurking in my mind somewhere too. Sources: Neven and the people on this blog, Chris Reynolds' DOSBAT, Tamino, David Barber's talk on rotten ice last year. Thank's to you all. Especially the amateurs.

2.2 Mkm^2

I had an exchange of emails with Govindasamy Bala of the Lawrence Livermore National Laboratory in 2007. My summary of his view after a few emails was 1. Planting (or keeping) trees in tropical regions is good. 2. Planting trees in snowy areas is bad. 3. Planting trees in other areas may be good or bad. His response was Points 1 and 2 are ok. Point 3 should be "planting trees in other areas may offer little benefit." The LLNL press release in 2007 was https://www.llnl.gov/news/newsreleases/2007/NR-07-04-03.html The situation is clearly complex. There are lots of other considerations e.g. if cities are cooled by trees will the energy use fall? http://www.fs.fed.us/psw/programs/uesd/uep/products/psw_cufr684_TreesAndGHG.pdf Trying to make the case for the use of wood, I had made this point to Bala at the time ... "I may have not made clear my concerns about the 'short term'. I am not suggesting that it is possible to stop climate change quickly. What I ask is "Will we need to bring in emergency, short term, measures to cut the carbon burden on the atmosphere?" For example, should much more biomass be used in the construction industry to lock up carbon in the fabric of buildings so it is stored for the lifetime of the building at least. I have heard that significant positive feedbacks have not yet been incorporated in the appropriate climate models (e.g. methane from the tundra) and that we may have an acceleration of climate change. Does this mean a tonne of carbon dioxide released now has a worse effect than one in a hundred years time? Do we need to think of emergency measures to buy time?" This is a big topic. Should it be on the Forum?

I went to the meeting with Julia Slingo (Chief Scientist, Met Office) and others speaking - including a civil servant from DECC,the UK Department of Energy and Climate Change. He thought that that sustainable oil and gas exploration in the Arctic was OK. He also that "climate change was the front an centre of what DECC does", "gas demand will rise", and stuff about keeping our emissions below the 2 degrees Celsius rise. His platitudes were so blatant I was laughing. I felt much sympathy with Julia Slingo she is put in the position of defending the climate models which we all know aren't performing well in the Arctic: One speaker had actually shown that graph of the CMIP4 models Neven posted in Models are improving, but can they catch up?. I (and others)asked about this and what the Met Office thought of the extreme weather events and the Jennifer Francis view that "it's the Arctic what's done it". She answered that the CMIP4 models were out of date to which I responded "The CMIP5 models aren't any better". (Actually they may be a bit better.) She said they had some new models that gave better results. She painted a picture of the climate being a very complex system, hard to model. I think she said that using simple trends wasn't the right thing to do. I'm fairly sure she said that there was no evidence that the Arctic was driving extreme weather events like the 2010 Russian fires or the Texas drought of 2011 or the high plains drought last year. At the Met Office they had related this to exceptional La Nina years in the Pacific. (She did mention a paper which suggested climate change was making the effects of La Nina worse.) So down in Exeter at the Met Office's Hadley Centre they are not convinced by Jennifer Francis. I think that may be true in the University as well. What really worried me is the seeming complacency of everybody that appears to be "doing their jobs" especially the DECC man and another speaker from the Foreign Office. They seemed nice people and not part of A-team's Hindenburg blimp safety committee - these people must know - but are just not getting the enormity of it all. I spoke to two people there with military connections they seemed to get the humanitarian impacts rather better. e.g. water will get scarce, the fertile river deltas will shrink and be inundated by rising seas and people will starve. The populated area of the Nile delta has already shrunk. European navies can cope with 1000 people coming across the Mediterranean, 10,000 is difficult. 100,000 is a very big problem. Also it's not pleasant picking dead bodies out of boats filled with fleeing refugees. Lack of water in Italy and Greece will be a problem in Europe but the really big worry is the USA. Failing empires have a tendency to seek war as a diversion so when the population of many of the states in the USA have little water .... I must admit I'm not sure if I understood what I was told or whether I was being strung along - and I suppose this has got off topic ...

Chris You say I don't like the science bashing that sometimes goes on here. Especially the regular attacks on the modellers. We are amateurs, and we shouldn't forget it. As amateurs we don't have reputations at stake if we make public pronouncements that are later shown wrong by events. I should get to see Prof. Julia Slingo, (Chief Scientist, Met Office) this week. I won't tell her that I trust you more than the Met Office modellers. I do - and that also goes for others on this blog. You obviously have the background to cope with your wide ranging reading and are in a position to give your judgements without pulling your punches. It would be impolite to tell Professor Slingo how this contrasts with her Met Office modellers, who may understandably be held back by reputational reticence. But should I say anything at all? Should I ask her why the models seem so wrong about Arctic sea ice?

Espen Feel free to continue this conversation HERE where I point out the following advantages of a carbon tax to create jobs: - It creates jobs - It reduces domestic demand for energy so it - closes the "energy gap" - reduces imports - increases exports - It redistributes from rich to poor Please note the last item. "Unrealistic"? Yes - but it's a mad dream to think we can escape this unfolding disaster and have cheap energy for the next few decades. "Unrealistic" is what we are left with.

Espen I don't think you can have read my blogs pieces or papers. Within the closed national economy I studied, subsidising the labour of the low paid creates jobs for them. If the subsidies come from increased taxes on capital and the labour of the higher paid, the affluent may have a downward pressure on their wages but since production rises (because more people are in work) this is partly offset by a higher GDP. The argument is similar if the subsidies are financed by a carbon tax: the biggest polluters - the affluent - may lose but the subsidies ensure full employment at the bottom of the labour market. Higher up the labour market, the affluent might have to cut their labour rates to get jobs but they could increase their living standards by cutting their pollution. In an economy that has substantial trade flows it would be necessary to tax imports on the basis of their carbon content. The goods produced from overseas would face high taxes if they had high embodied carbon. This would repatriate "green" jobs and the subsidies could plug any gap that was left by cutting "polluting" jobs. Question: Did Denmark recycle it's environmental taxes into creating jobs for the low-paid? Crandles. China would quickly clean up its act if we taxed imported goods on embodied carbon. I don't always agree with Myles Allen but I heard him recently praise California for it's emissions standards for cars. Because California insisted on better standards the rest of the USA had to follow. That's a good example. A well designed carbon tax regime would spread throughout the world in much the same way if it were implemented in a market of sufficient size (e.g. Europe). P.S. Hansen's carbon fee would work in a similar way but perhaps less directly.

Alex, Neven (The full version of this didn't appear for some reason. Too long?) it is not at all clear, how high carbon price can global economy endure – actually, the financial crash of 2008 was helped by high oil prices, What do you mean by "global economy"? It’s perfectly possible to have full employment and a high carbon price. Job creation doesn’t need economic growth but carbon intensive goods and services must be made more expensive and labour intensive goods cheaper. Read the rest here

Aaron Any carbon tax that works is cheaper than real global famine. Yes. I believe James Hansen has suggested $1000 per tonne of CO2e. I was going for £1000 per tonne. What's your tax rate? Terry Is there really sufficient time for any of these schemes? If anthropomorphic emissions suddenly ended tomorrow would this save the Arctic ice cap? Let's keep trying. What about anthropomorphic extractions? 1. Biomass burning with carbon capture? 2. Olivine? 3. & many others the market could provide. Any one nation could implement a high carbon tax - and have full employment - and enable schemes like these.

The British Geological Survey say If the [carbon price] remains low, CCS will be slow to develop because there is no financial incentive. When CCS technology is better developed and proven, its costs may lower. Some people suggest that money spent on CCS will divert investments away from other solutions to climate change. That means we need a high carbon price soon so that power stations can become carbon negative with CCS and biomass. Have we the time to "allow the current infrastructure to reach the end of its natural economic life"? The Arctic snow is disappearing fast with the Arctic sea ice and messing with our weather and food supplies!

I have had an interesting discussion on carbon taxes with Timothy Worstall of the Adam Smith Institute. He is a regular contributor to Forbes Magazine and the Daily Telegraph. He seems very influential. He is an advocate of a carbon tax but I don't think he has yet appreciated the scale of climate change. To my surprise he calls himself "rather a lefty" I don't agree with all he says but he's worth reading. I have written before on carbon taxes and spend some effort to get my favorite economists to do more. They support it but seem to do little. One big problem is that economic models do not disaggregate their labour sectors sensibly. They could then show that a carbon tax recycled into creating employment for the low paid (who are the ones out of work) could create full employment without economic growth

I am a founder member of the No miles high club (Motto: "We promise never to fly until we break our promise") and run the (very limited) No Planes website. This means I want to know how bad (or otherwise) are the effects of aviation on climate - I am already confused afere reading Unger et.al Attribution of climate forcing to economic sectors which suggests that the short-term effects of aviation may be to cool the Earth. I have looked briefly at one of the papers Chris Reynolds suggested Contrails, Natural Clouds, and Diurnal Temperature Range by Dietmüller et.al. It hasn't helped much but this interested me: Another point questioning the Travis hypothesis is that the decrease in DTR of 1.1 K for 11–13 September 2001 lies within the 99% confidence interval of natural DTR variability, indicating that a 3-day anomaly of the respective magnitude can be largely explained by natural fluctuations. Does this mean that unless an event has a 99% chance of being consistent with a particular theory of ("99 to one on" in horse racing terms) it should not be considered as part of the evidence that "Science" can pass on to policy makers?

Steve Thanks. That's a good example. Although the story is still available at the URL you gave, it is no longer seems to be referenced on the science-environment section of the BBC website. Much older stories are. I will raise this with MP. Surely they are not putting stories up to cover their backs then making them difficult to access. I have also been interested in the pattern of reporting from different journalists. Many of the more realistic stories seem to come from outside the usual team.

Thanks Boa05att Looks to me that the BBC/Met Office are consistently choosing the “it might not be climate change” story line. The piece gives me the impression that we don't really know if it's climate change so we need not worry too much. It might be the Arctic sea-ice loss or just the long-standing North Atlantic Oscillation. I find this typical of many BBC reports. Jennifer Francis is much clearer: While various oceanic and atmospheric patterns such as El Niño, La Niña, and the North Atlantic Oscillation have been blamed for the spate of unusual weather recently, there’s now a new culprit in the wind: Arctic amplification. Directly related to sea-ice loss and earlier snowmelt in the Far North, it is affecting the jet stream around the Northern Hemisphere, with potentially far-reaching effects on the weather. OK, the BBC piece is not dissimilar to what Jennifer Francis says but to the casual observer they have very different impacts. I think the BBC is soft peddling climate change - again. This may be down to their choice of experts. A decent debate putting the BBC's favourite experts to the test would be interesting.

In Downpours make 2012 England’s wettest year on record a Met Office spokeman is reported as saying that it was impossible to say whether the spate of wet years was due to climate change. “Britain is a wet country,” he said. “There will always be dry spells and wet spells. This year’s wet weather has been due to a buckled jet stream. Normally it is straight and pushes wet weather systems far to the north. It hasn’t done that this year.” Comments?

When I'm less susceptible to seasonal cheer, I will read A-Team's last entry again but does it mean climate scientists have failed the test of courage. I sympathise with them - I would probably fail this test too but give me a few years when death is nearer I hope I would do better. But this may not be tested. I'm not in the firing line. Seasons greetings.

Crandles Do you argue that if we apply some unspecified trend function the results of the CMIP5 models, it is possible to say There is very high confidence that CMIP5 models realistically simulate the annual cycle of Arctic sea-ice extent This means the models should get realistic results for the phase of the annual cycle and the amplitude of the annual cycle. Do they catch the slippage of maxima and minima? Is the asymmetric change of maximum and minimum values simulated correctly? But in these arguments over semantics are we missing a more damaging possibility - that the draft of Chapter 9 is designed to confuse and paper over the failings of the CMIP5 models? I hope not. That would be very dangerous for the whole world.

Neven It's such a relief to me that you have taken up this issue. Can I hope that you can do something to engage 1. The European Commission? 2. The BBC? The reply to BlueSky from Connie Hildegaard, the European Commissioner for Climate Action, showed that the Commission are following the IPCC slavishly and are in denial about the seriousness of climate change. I hope you can highlight their failings. The BBC - as a public body - should tell us the truth. They are also in denial. My TweetsToTheBeeb and letters via my MP are easily ignored. You (rightly) have the status to make a difference. I hope you can put the BBC on your list for action. Thank you. Thank you. Thank you.

Espen Olsen I think the BBC is terrible on climate change. (See my TweetsToTheBeeb. But the film you mention wasn't the BBC - it was Channel4. See Wikipedia The great global warming swindle

On Record dominoes 13 Bluesky posted a letter from the European Commission saying that the IPCC was the body they followed on climate change. He got a more explicit reply than a similar one I received last year. There was something about a post I made following Bluesky's that preventing it getting posted so I have put a couple of pieces on my BrusselsBlog. The latest piece criticises the leaked draft of IPCC Chapter 9 (Evaluation of Climate Models) that Apocalypse4Real pointed us to. This says There is very high confidence that CMIP5 models realistically simulate the annual cycle of Arctic sea-ice extent, and there is high confidence that they realistically simulate the trend in Arctic sea-ice extent over the past decades. I did a bit of work on a part of their figure 9.24 which shows the CMIP5 estimates of Arctic sea ice decline compared with satellite measurements supplied by the NSIDC. I added in the 2012 September sea ice extent. The result has a similar message to the graph shown on this blog under Models are improving, but can they catch up?. This was more extensive and used the CMIP3 climate models. I just can't see how the IPCC Chapter 9 can justify their claim above and I don't see how the European Commission can support their claim that The European Commission bases its climate policies on the best available science and on the scientific consensus of experts in the field of climate change. The scientific consensus view on this subject is reflected in the IPCC (Intergovernmental Panel on Climate Change) Fourth Assessment Report from 2007. Am I missing something?

Kevin Anderson link corrected: http://www.ecoshock.info/2012/11/kevin-anderson-what-they-wont-tell-you.html

Darren Wood mentions Sea-level rise from polar ice melt finally quantified http://www.bbc.co.uk/news/science-environment-20543483 This says The findings are in line with the broad range of forecasts in the 2007 assessment by the UN's Intergovernmental Panel on Climate Change. Is this correct?

Neven, Thanks for your earlier comment about the BBC report 'Frankenstorm' bears down on US east coast. "I've just read the article. I'm not seeing any problem with it, to be frank.". I read the BBC climate reporting with a jaundiced eye. I suspected the "perfect storm" reference in the article was another example of the BBC downplaying climate change - a possible example of "Don't worry it's happened before". I wasn't sure it was a good enough example to add to my tweets to the BEEB. To conclusively show that the BBC has the wrong balance on climate change requires in-depth study that requires much more resources and time than I have available. But the tweets to the BEEB are there for me to follow it up if I ever have the time as well as an attempt to bring the issue to their attention. I do detect some shift in BBC reporting: There is now less of the false balance between climate scientists and sceptics but, except for Peter Wadhams and sometimes James Hansen, they don't seem to examine the climate-is-worse-than-the-official-line issue. From reading your blog I am sure you agree that the official line on climate is way behind the real world. (e.g. Models are improving, but can they catch up?). I would like the BBC's new balance to be between the officials, like the IPCC, and those that can put the arguments forward that think climate change is much worse - and much more complicated. I think your blog should be part of this balance. What impression do you and others have on the BBC's climate reporting? Should I save my effort and stop tweeting the BEEB? I have plenty of other things to do.

BBC says nothing to see here. Move along please: Forecasters say Sandy is similar to another late October storm - when several weather systems, including a hurricane, combined along the US Atlantic coast in 1991, leading to what was dubbed "the Perfect Storm". 'Frankenstorm' bears down on US east coast Comments?