27/08/2019

The Amazon Fires And The Dilemma For Climate Scientists

Sydney Morning Herald - Andrew Glikson*

As fires rage across the Amazon – dubbed the "lungs of the planet" given it produces 20 per cent of the oxygen in the atmosphere – and while forests are ablaze in Siberia, Alaska, Greenland, southern Europe and parts of Australia, climate scientists might be justified in saying: "We told you so."
They tend not to gloat, however, about the tragedy that confronts us all.
The battle against fire in the state of Mato Grosso, Brazil, on Friday. Under increasing international pressure to contain the fires sweeping parts of the Amazon, President Jair Bolsonaro authorised the military to battle the massive blazes. Credit: AP

Brazil alone has had 72,843 fires this year. The pace of global warming is exceeding projections, astounding climate scientists. Within the past 70 years or so major shifts in climate zones and an accelerating spate of extreme weather events—cyclones, floods, droughts, heat waves and fires— is ravaging large tracts of Earth.
Scientists Jos Barlow and Alexander C. Lees write in The Conversation that “climate change itself is making dry seasons longer and forests more flammable. Increased temperatures are also resulting in more frequent tropical forest fires in non-drought years. And climate change may also be driving the increasing frequency and intensity of climate anomalies, such as El NiƱo events that affect fire season intensity across Amazonia.”
And yet the human causes of climate change remain subject to extensively propagated denial and untruths, despite their foundation in the basic laws of physics and the empirical observations of global research bodies such as NASA and the National Oceanic and Atmospheric Administration in the US, the UN's Intergovernmental Panel on Climate Change, the World Meteorological Organisation, and our own CSIRO.
Climate scientists find themselves in a quandary similar to medical doctors who need to break the news of a grave diagnosis. How do they tell people that the current spate of cyclones, devastating islands from the Caribbean to the Philippines, or the flooding of coastal regions and river valleys from Mozambique to Kerala, Pakistan and Townsville, can only intensify in a rapidly warming world?
How do scientists tell the people that their children are growing into a world where survival under a mean temperatures 2C above pre-industrial levels may be painful, and in some parts of the world impossible, let alone under 4C rise projected by the IPCC?
The Cassandra syndrome is alive and well. (Apollo gave Cassandra the gift of prophecy but, humiliated by her unrequited love, he also placed a curse on her, ensuring no one would believe her warnings.)
Throughout history, messengers of bad news have been rebuked or worse. Nowadays, many scientists are reticent to publish their climate change projections. Given the daunting scenarios they confront, many find it difficult to talk about it, even among friends and family.
Atmospheric levels of CO2, methane and nitrous oxide have reached a combined level of almost 500 parts per million, intersecting the melting threshold of the Greenland and west Antarctic ice sheets and heralding a fundamental shift in the state of the terrestrial climate.
As fires consume large parts of the land, it would appear parliaments – including Australia's – are preoccupied with economics and international conflicts while they hardly regard the future of  civilisation as a priority.

*Dr Andrew Glikson is an earth and climate scientist at the Australian National University.

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