Joe Romm at Climate Progress believes the Paris climate talks should not be written off as a failure if they don’t do enough to keep warming below 2°C. He thinks the CFC ozone layer example is apt. The Montreal Protocol was concluded in 1987. Initially the protocol’s targets and timetables slowed the rate of growth of concentrations only slightly and would have still led to millions of extra cases of skin cancer by mid-century.
President Reagan endorsed the protocol, and the Senate ratified it. By the end of 1988, 29 countries and the European Economic Community — but not China or India — had ratified it. The treaty came into effect the next year. But it took many more years of negotiations, continuous strengthening of the scientific consensus, and significant concessions to developing countries before amendments to the treaty were strong enough and had enough support from both rich and poor countries to ensure that CFC concentrations in the air would be reduced.
2. 2013 record heatwave ‘virtually impossible’ without climate change
That’s according to a new report from the Climate Council.
The country experienced its hottest day, month, season and calendar year in 2013, registering a mean temperature 1.2C above the 1961-90 average.
The Climate Council says recent studies show those heat events would have occurred only once every 12,300 years without greenhouse gas emissions from human activities.
Record hot days have doubled in Australia over the past 50 years. During the past decade heat weather records were set three times more often than cold ones.
Heatwaves across Australia are becoming hotter, lasting longer, occurring more often and starting earlier.
The ABC article has handy links to other sites.
The following graph shows the number of days each year where the Australian area-averaged daily mean temperature was above the 99th percentile for the period 1910-2013:
3. Two degrees by 2036
Michael Mann using an Earth energy balance model has calculated that we could reach 2°C of warming as early as 2036. To stay within the 2°C guardrail we need to limit CO2 concentrations to 405 ppm. It would be 450 ppm but for the aerosol issue. If we cease burning coal we lose the cooling effect of the crap that coal spews into the atmosphere along with CO2.
Mann has done the calculation on the basis of climate sensitivity of 3°C. Problem is, he says, that this modelling is based only on short term feedbacks.
David Spratt at Climate Code Red has done a long and thorough post based on Mann’s article. Spratt looks in some detail at the longer term climate sensitivity issue, drawing also on the work of James Hansen, Aradhna Tripati and others. Hansen found that climate sensitivity with long term feedbacks was considerably higher than 3°C; Tripati found that in the Miocene with CO2 concentrations similar to now “temperatures were ~3° to 6°C warmer and sea level was 25 to 40 meters higher than at present”.
Spratt also reminds us that 2°C warming is not safe.
4. Would turfing Abbott help climate change policy?
In short, yes, but perhaps not a lot. The conservative side of politics is still infested with climate change denialists.
Mother Jones in an article One of the World’s Worst Climate Villains Could Soon Be Booted From Office would clearly like to see the back of Abbott. Julie Bishop has a background of denialism, but is pragmatic and has understood from the Lima experience that our stance on climate is negatively affecting our international standing.
Turnbull stated back in 2009:
“I will not lead a party that is not as committed to effective action on climate change as I am.”
He would now, of course.
See also Lenore Taylor at The Guardian.