Mention Stefan Rahmstorf and James Hansen at any climate science gathering, anywhere, and you’re guaranteed instant recognition, a legacy of many decades as leaders of the global effort to understand Earth’s climate signals.
In recent separate research papers, they’ve now raised the alert level. Planetary warming, they say, is accelerating. What’s more, says Hansen, science’s established understanding of the impact of a doubling of atmospheric carbon dioxide concentrations is far too conservative – by a factor of 50 per cent.
Re-evaluating post-2000 data in all the major global temperature records, Rahmstorf and statistician Grant Foster removed natural variability influences to find that since 2015 Earth’s surface temperature has risen significantly faster than in any previous ten-year period since 1945.
The multi-year average remains below the 1.5C “safe” limit, but the Rahmstorf-Foster analysis of trends since 1980 shows the rise steadily accelerating, doubling after 2015. They found that even discounting the past two extreme-high years, we’ll be beyond that 1.5C baseline by late 2026. That’s next year.
By coincidence the US administration under Donald Trump, who has said repeatedly that global warming is a hoax, has just put out its own climate explainer. The review avoids the hoax claim, but does say warming’s impact is overrated, that more carbon dioxide could be beneficial and that extreme weather events aren’t worse or more frequent than normal.
It’s a comforting scenario, as the review’s instigator, Trump’s energy secretary and former oil and gas executive Christopher Wright, would have expected when he chose the five review authors. Four of them are climate scientists and the fifth is an economist. But as Wright said in his foreword to the report, all five reviewers believe that energy poverty is a more pressing issue than climate change.
Except for the tiny cohort from which Wright selected his reviewers, all the world’s scientists say that’s a complete furphy. There’s no need here to go into reasons why; they’ve been stated repeatedly, countless times. When a huge majority of scientists in relevant disciplines say humans affect climate, with devastating effect on all life if left unattended, it’s foolish to believe otherwise.
The depth of that foolishness and the danger of following the business-as-usual path is being revealed daily in this northern hemisphere summer. Record-breaking rain events, mudslides and flash floods, storm surges, heatwaves and wildfires in places unprepared for them are all telling and often-deadly reminders of how close the world is to a climate out of control.
“A genuine apocalypse” is how David Penberthy described South Australia’s algal bloom in the Sunday Tasmanian early this month, adding that “it would not be happening at all if the water was not so much warmer than it has been historically.” The multi-year Tasman Sea heatwave is a persistent reminder that this island may not be far behind.
South Australians were indignant at Canberra’s excuse for its slow response to the catastrophe – that it had to affect more than one state to get national support. Last week, news of a bleached Ningaloo Reef in the continent’s far north-west made coral bleaching – another outcome of marine heatwaves – a multi-state issue, and therefore, surely, a national disaster. An international one, even.
All Australians should be indignant at decisions by new environment minister Murray Watt, starting with his May decision to keep the door open to expanded gas processing in northern WA, a project it has been estimated will add 88 million tonnes to global carbon pollution.
Last week, knowing that captive breeding of the critically endangered maugean skate had so far been unsuccessful, Watt gave a free pass to continued Macquarie Harbour salmon farming.
The minister was able to do both these things because of an infamous pre-election amendment to environment laws preventing ministers from reviewing past decisions even where new scientific evidence dictated otherwise.
People like me – including me – keep making assumptions about our society that are fundamentally wrong. We keep assuming that clear, demonstrated, proven fact will always prevail over short-term convenience and political opportunism.
We are approaching a long-awaited crunch time for human existence. Government can choose the Trump response to climatic and environmental threats, to deny they exist and act accordingly. Or it can take the position of other Western countries, including Australia, and pretend it’s taking effective action when it’s not.
Here’s a third option. The political class can decide it’s time to be honest, to admit business as usual is only darkening the clouds gathering over our future and resolve to do things differently. In this exceptional moment in its history, Tasmania has an opportunity to start that process, right now.