James Hansen’s name looms large over any history that will likely be written about climate change.
Whether you look at the hard science, the perils of political interference or modern day activism, Dr Hansen is there as a central character.
In a 1988 US Senate hearing, Hansen famously declared that the “greenhouse effect has been detected and is changing our climate now”.
Towards the end of his time as the director of NASA’s Goddard Institute for Space Studies, Hansen described how government officials had on other occasions changed his testimony, filtered scientific findings and controlled what scientists could and couldn’t say to the media – all to underplay the impact of fossil fuel emissions on the climate.
In recent years, the so-called “grandfather of climate science” has added to his CV the roles of author and twice-arrested climate activist and anti-coal campaigner. He still holds a position at Columbia University.
So when Hansen’s latest piece of blockbuster climate research was finalized and released earlier this week, there was understandable global interest, not least because it mapped a potential path to the “loss of all coastal cities” from rising sea levels and the onset of “super storms” previously unseen in the modern era.
So what is Hansen claiming?
Well, the first thing to understand is that Hansen’s paper, written with 18 other co-authors, many of them highly-reputable names in climate science in their own right, is far from conventional.
Most scientific papers only take up four or five pages in a journal. Hansen’s paper - in the journal Atmospheric Chemistry and Physics - grabs 52 pages (although it’s hard to quibble over space when you’re laying out a possible path to widespread global disruption and the complete reshaping of coastlines).