"I'm beyond depression."
These are the three simple words that help one of Australia's most eminent climate scientists, Professor David Karoly, get through the day. And there's a pretty interesting back-story behind the phrase.
It all goes back to a conversation Karoly had with Bob Brown, ex-leader of The Greens and an iconic figure in Australian environmentalism.
The two were talking about the frustration of trying to communicate their concerns as effectively as possible to the public (the environment in Brown's case, climate change in Karoly's). And Brown told Karoly that he exists in a state which is beyond depression.
"I agree with him," Karoly explains in Episode 4 of Breaking The Ice, HuffPost Australia's podcast series about the people behind the climate science.
"Why don't we give up and just get depressed? My answer is the same as Bob's.
"I'm beyond depression. If I understand the problem and the difficulties in addressing it, and just give up... how can I possibly expect any other person to recognise the scientific evidence, to understand the solutions but the difficulty of achieving those solutions, and to do something in trying to achieve those solutions when David Karoly -- an expert in this area -- has given up?"
Like many climate scientists, Karoly has become a controversial figure just because he researches and teaches the facts about human-caused global warming.
Certain politicians, media figures and fossil fuel industry figures won't accept those facts. They often construct a false "debate" around the data he and his colleagues gather. Or they ignore the data altogether. Or worse still, they attack the scientists who create it.
Karoly has been vilified more than most. But he doesn't let the criticism cut at either his professional credibility or personal life.
"To be honest I don't find being called a 'warmist' in any way pejorative," he says, of a term often employed against him and other climate scientists.
"I don't find a description of myself as an 'alarmist' pejorative either, and the reason I don't is because one of the dictionary definitions of 'alarmist' is a person who raises alarm or raises concern.
"Given the evidence that I have assessed -- about the role of human-caused increases in greenhouse gases and their impact on the climate system, and then the impact of climate change on water resources, agriculture, ecosystems, coastlines, food, people, human health -- there are very, very good reasons for wanting to raise alarm.
"This is not chicken little describing the sky as falling. This is a person looking over the horizon and even looking at the evidence now and saying 'we are already seeing major adverse impacts from human-caused climate change'.
"Unfortunately the Australian government at present -- and many other governments around the world -- are fiddling while the climate system warms."
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