There is nothing particular new in this piece by Stefan Rahmstorf in New Scientist but it is clear and well-written. The year 2013 is likely to involve record high global temperatures simply because of the trend growth in temperatures (0.16 degrees C per decade over the past 30 years) and because a new El Nino is approaching. The El Nino effects as well as volcanic activity and solar activity create short-term cycles around this rising trend that dishonest denialists have cheery-picked to seek to show that temperature increases are not continuing. But the trend rates of temperature increase are a fact not a theory. The accepted theory explaining these trends is the increase in Greenhouse gas emissions. Rahmstorf asks what new dishonesties will be used to justify denialism in 2013? If next year is a new record then 14 years out of the last 16 will be hottest ever recorded. One would think that strident hysterics in the denialist movement would feel some slight measure of discomfit at the self-evident lack of realism in their views.
Or will there be a new class of deceit introduced? Twists on the “climate change has always occurred” or “even if it does occur it won’t be harmful and even if it was we can’t do anything about it” lies.
Update: I have been reading the second edition of Neil Robert’s book The Holocene: An Environmental History. This is a careful history of the global environment over the past 10,000 years. Its very cautious on the issue of climate change causation noting that climate did display quite a bit of instability during the Holocene. He is therefore cautious about drawing conclusions. But he does inspect data on the connection between CO2 levels and temperature over the last full glacial-Interglacial cycle using the Vostok ice core data from Antartica which he describes as providing the “most complete and direct record of greenhouse gases and temperatures” over this period. His conclusion is straightforward: The data “strongly supports a link”. Its a great read by the way and discusses at length other very long term environmental changes introduced by the development of agriculture.