The target should not be 1.5°C; rather we should aim for a safe climate. James Hansen told us in 2007 that to achieve a safe climate we need to bring GHG concentrations down to 350 ppm as soon as possible. That’s CO2 equivalent, not CO2. Current CO2e is not often quoted, but would be around 500 ppm on the basis that CO2 is about 80% of total GHGs. Also we need to focus on what we are doing to the planet over centuries and millennia, not just the next 50 to 100 years.
However, the IPCC team putting the report together were not asked what the goal should be. They were asked to build a scenario for achieving the 1.5°C warming limit specified as desirable in the Paris Agreement of 2015, and to look at the impacts of a 1.5°C world as against a 2°C world. Two Degrees came out of Europe in the 1990s, achieved a general currency, then became the official goal of at the Conference of Parties of the UNFCCC in Cancun in 2010. At that time there was a move mainly by many of the island states vulnerable it inundation for a more ambitious target. Essentially the whole group at Paris agreed to try.
However, while two degrees was commonly seen as a guardrail for a safe climate even by many scientist, it was never a scientifically derived goal for a safe climate.
Patrick Brown of Stanford University in California, working with Ken Caldeira, has found that the planet will warm 10 to 20 per cent more than previously thought. Here is the critical graph from their research:
I can’t comment on his blog, because the Askimet software has got me marked as a pest, and my comments go straight to spam. There is no facility for telling Askimet I’m OK, so there it is, I’m as good as banned. So I’ll make my comments here, which are in any case longer than is form for comments there.
should we be seriously looking at what the safe levels of CO2 in the atmosphere are for human beings?
That was in the context of an informed comment that we have not seen CO2 levels above 320 ppm for 27 million years, which predates hominid evolution. Studies indicate that 600 ppm globally, which is where we could be by 2050, might just render us extinct.
To jump to the chase, we don’t really know what the full effects of elevated CO2 will be, or indeed what they are now. However, indications are that as CO2 rises, our brains will work less well and we will become more limp and sluggish. A bit like a frog in a pot of water gradually being heated. Continue reading CO2 is scrambling our brains, but will it kill us all?→
Donald Trump in announcing that the USA will withdraw from the Paris Climate Agreement made a big fuss about the Chinese being able to increase their emissions, and that this was unfair to the US economy.
a revised worst-case sea-level rise scenario of 2.5 metres by 2100, 5.5 metres by 2150 and 9.7 metres by 2200. It says sea level science has “advanced significantly over the last few years, especially (for) land-based ice sheets in Greenland and Antarctica under global warming”, and hence the “correspondingly larger range of possible 21st century rise in sea level than previously thought”.
Start stopping now, is the short answer. No new coal mines, oil wells or gas fields, and start decommissioning existing ones now. “Managed decline” is the new imperative.
A new study released by Oil Change International, in partnership with 14 organizations from around the world, scientifically grounds the growing movement to keep carbon in the ground by revealing the need to stop all new fossil fuel infrastructure and industry expansion. It focuses on the potential carbon emissions from developed reserves – where the wells are already drilled, the pits dug, and the pipelines, processing facilities, railways, and export terminals constructed.
The summary sentence tells us that “coal and gas will begin their terminal decline in less than a decade”. Frequently the title of an article and the summary lead-in sentence are not written by the authors. In this case the “terminal decline” of coal and gas is more than a little misleading. Continue reading Bloomberg’s New energy outlook, 2016→
French President Francois Hollande did not turn up to give the opening address at a major climate science conference in Paris recently, being otherwise occupied with questions concerning Grexit. Had he been there he may have been able to explain why France has restored subsidies to the French companies building coal-fired power stations in other countries.
When I heard Greg Hunt spruiking the first auction under the Emissions Reduction Fund (ERF) last week, he sounded like a used car salesman. He has form on cherry picking statistics and imaginative accounting, so it’s best to ignore what he said and look to other sources (please note, there is other commentary in the link, including from Tim Flannery).