IPCC AR5 – WG1 Physical Science Basis

The UN Intergovernmental Panel on Climate Change (IPCC) now says we are as certain that humans are dramatically changing the planet’s climate as we are that smoking causes cancer.” (J. Romm)

Working Group 1 of the IPCC (Intergovernmental Panel on Climate Change) has issued the first part of Assessment Report 5. This Report covers the Physical Science Basis for anthropogenic climate change.

Global warming is confirmed yet again: “Total radiative forcing is positive, and has led to an uptake of energy by the climate system. The largest contribution to total radiative forcing is caused by the increase in the atmospheric concentration of CO2 since 1750.” This statement is backed up by direct measurements of the climate system.

And it is human caused: “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.” …and… “It is extremely likely that human influence has been the dominant cause of observed warming since the mid-20th century.

Even models are better: “Climate models have improved since 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).

Dealing with projections and required action: “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.

There is little change in the climate sensitivity (still in range 1.5 to 6). The “transient” climate sensitivity (that likely over decades or centuries) is given as in the range 1 to 2.5 (sensitivity is the expected rise in temperature for a doubling of CO2). The response to the cumulative quantity of GHG emissions

These statements are based on a broad range of measured data from across the entire climate system and on close monitoring of our burning of fossil fuels and other human activities such as forest clearing.

Of course, to most this is no surprise. The main message of the report is that since AR4, nothing much has changed only the urgency to act has increased. It is all the more certain that we are heading for disaster if we don’t cut emissions. Scientists hold the same confidence in the evidence that smoking kills as they do that humans are causing global warming.

The huge effort on research in the last 7 years has failed to find any doubt that we are causing our planet to warm by our use of fossil fuels and that we must act swiftly to stop this or suffer serious and long term consequences.

So, the science is settled (and has been for some time). What then should we do….

The Report uses projections of how the climate will change. These are based on new scenarios that relate to the amount of GHGs in the atmosphere (Representative Concentration Pathways: RCP2.6, RCP4.5, RCP 6.0 and RCP8.5, Skeptical Science has a good rundown on these… http://www.skepticalscience.com/rcp-guide-part1-post.html).

These pathways are similar to previous future scenarios in that they give a range of human emissions from strong reductions in emissions (RCP2.6) to business as usual emissions (RCP8.5). RCP8.5 sees global temperature approaching 4.5 degrees by 2100 – a disaster scenario. The modeling is conservative because it omits some positive feedback effects such as permafrost melt and loss of arctic sea ice.

There is little difference to the previous AR4 in that strong cuts are required to give us any chance of staying below the 2 degree limit. 2 degrees of rise is the internationally agreed safety rail beyond which dangerous climate change would occur.

Many scientists believe we may be already too late to stay below the 2 degree limit, essentially because of poor decisions made by our leaders over the last few years. Certainly, the failure at Copenhagen had a lot to do with it.

For a 2 in 3 chance of staying below the 2 degree limit, total emissions needs to be limited to a total budget of around 800 GtC – we have so far used up 530 GtC of this amount so there is only 270 GtC still available. This equates to the reduction scenario represented by RCP2.6. Including reduction in aerosols (particles from fossil fuel burning) and melting of permafrost would reduce the emissions budget limit still further.

To achieve RCP2.6, global emissions need to peak before 2020 and reduce at around 5% per year. Current thinking is that RCP2.6 is not a practically achievable scenario as we have already gone past the window to achieve it.

Finally, it must be remembered that the IPCC reports are highly conservative and are regularly revised ‘upwards’. This results from the highly scrutinized process and editing by the many countries that are involved. Consequently, the outcomes of the Report are highly robust and generally we can expect that the reality will turn out to be worse.

Further info…  http://www.realclimate.org/index.php/archives/2013/09/the-new-ipcc-climate-report/    http://thinkprogress.org/climate/2013/09/27/2681861/15-things-ipcc-report/   http://www.businessspectator.com.au/news/2013/9/27/science-environment/warming-hit-home-australians-ipcc .

A few other points to note in AR5:

Atlantic Meridional Overturning Circulation (AMOC) research shows this current is likely to slow (between 10% and 35%). This slowing is likely to impact on the European climate (make the region colder).

Sea Level Rise is expected to be between 0.3m and 1.0m for the range of scenarios (slightly increased from AR4). There is insufficient confidence in the empirical assessments to include them even though they predict up to double the rise. Also, the contribution of Antarctica is still not fully included due to the uncertainty of the actual melting there. Many researchers consider destabilization of marine based Antarctic ice (such as in West Antarctica) to be a serious risk.

Ocean acidification is very well defined as it depends directly on the emissions that occur. The values for reduction in ph (i.e. acidification) are:-   0.15 for RCP4.5, 0.2 for RCP6 and 0.31 for RCP8.5.

Large climatic changes are already locked in and likely to continue for centuries, unless GHG’s are actively removed from the system. Around 25% of the CO2 released will remain in the atmosphere for 1000 years, even if we stopped now.

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IPCC Report Due Tomorrow

With the next IPCC Report due to be released tomorrow, there has been some debate designed to undermine the science even before it is released. There has also been some effort put into diluting the contents of the report even before we get to see it.

Unfortunately, the report will repeat the basic statements regarding science that we all dread to hear… that warming is occurring, that there is already considerable change in the pipeline and that we must act quickly if we hope to slow the warming.

It would be great to listen to people like Curry or the other advocates of low impacts (or even that its all a hoax) but every time such statements are looked into, it becomes obvious how they are ignoring basic scientific knowledge regarding our climate.

But enough of the negativity, what can we do to fight the changes? We should be focusing on the opportunities, not the threats.

First there is the replacement of our fossil fuel power stations with renewable energy. This is the largest target in our use of energy. This would be followed by:- the vehicle fleet (replace with electric) cement production (find alternatives) aluminium/steel making and industrial processes (develop new methods) .

There are challenges with these, but we have time if we deal with the big problems first (power stations and vehicles).

When all this is done, we may have to look at extracting GHGs from the environment. There are already methods available to extract CO2 from the air. This would be a big task and require a lot of energy, but innovative methods may be developed in the longer term.

Still pressing is the need to get on with the job of cutting fossil fuel use. It is becoming more obvious that this will only happen when people are directly impacted. Extreme weather is likely to be the driving force. If only we didn’t have to be hit by floods or bushfires before people wake up to the threat.

ENSO appears to be looking neutral for the next 6 months which generally means quiet weather (http://www.bom.gov.au/climate/enso/). Lets hope it stays that way – the next El Nino will not be pleasant.

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Climate Future talks to Permaculture group

This Tuesday, there will be a talk at the local Permaculture group at the Hall in Anzac Road, Tuggerah – 7pm. All are welcome (small donation if not a member).

Hear the latest on the science and a run-down of the global targets we need to aim for. Hear what plans there are to replace our fossil fuel power stations with renewable energy. Find out what you can do yourself to keep Australia on track to fulfil our obligations to the world community and to future generations.

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New Senate Balance

There are to be a large number of independents in the Senate this time. It looks like the Greens will be out in the cold. Decisions related to climate are likely to be made by a couple of people who know nothing about the subject.

It is likely that Bob Day of Family First and David Leyonhjelm of the Liberal Democratic Party will side with the Govt. The Palmer United Party reps, Glenn Lazarus and Jacqui Lambie will also be in the denial camp. John Madigan of the DLP appears to be on the do nothing side also.

This leaves Nick Xenophon who thinks the Carbon Tax is not a good idea but supports action and two others who don’t appear to know anything about climate:- Ricky Muir of the Australian Motoring Enthusiasts Party and Wayne Dropulich of the Australian Sports Party. Both these appear to have got in by mistake – never expecting to take the trick!

These three voting with the Greens and Labor would …

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At long last! Climate Change figures in the debate

After a long election campaign of some 7 months, including a change of leader and many policy debates, Climate Change finally raised its head on Monday – just three days before the media blackout.

The most important issue! And ne where the main parties differ:-  How to deal with Climate Change. There are two parts to this:- one is how to mitigate (reduce emissions) and the other is how to adapt. Adaptation has not raised a single question during the entire campaign. Not even the Greens have raised this issue or perhaps the media have failed to report such. But I will focus on mitigation as that has been the main part of the political debate for a long time.

First, lets look at the target: 5% is agreed by both Labor and Coalition parties, that is, 5% reduction on Australia’s year 2000 emissions by 2020. The argument is that this is a lot as on projections for increased demand in recent years, we would have increased our emissions by around 10% between 2008 and 2020 under the business as usual scenario. It should be pointed out that this is a 4% reduction on 1990 emissions – a woeful target when compared to the EU which has already reduced their emissions from 1990 levels by 11% and plan to reduce a further 10% or so by 2020.

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Copacabana Climate & Energy Talk

Climate Change Talk
Copacabana Surf Club on 28th August starting 7pm

Check out:-    http://copacabana.nsw.au/news/   for more info.

This talk will set you up for the coming election. What should the government be doing, what about renewable energy, can you help with local energy development? Grab a tea and talk to others with similar concerns.

Find out more and discuss the issues.

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Saving Lives Trumps Saving Property Values

By JOHN ASQUITH June 7, 2013, 10:30 p.m.

SEVERAL years ago, I was driving south from Brisbane and got trapped in floods at Bellingen. After a massive downpour and a slightly later tidal surge, the waters rose rapidly. It was just on dark. Barely able to see the centre line of the road, I drove on slowly, expecting to see a road block.

I rang 000, but all the emergency services were rescuing and evacuating people from Harwood Island. I stopped in the middle of the road with other drivers,  and we decided to form a convoy and drive back to find higher ground.

I rang home to hear loved voices but did not tell them of my fear. We had no idea of where the flood was coming from, no sense of where to find safe ground. We were terrified.

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