10 January 2012
We have just met the first emissaries of the great continent of ice! I did not win the sweep: they hove into sight out of the mist at 8.04 am this morning. They are still distant, mysterious presences to us, not yet revealing their depths to the light.
When they appeared alongside the Aurora in late 1911, Charles Harrisson dashed below to get his paint box and canvas. He may have seen photographs of icebergs before but never in colour. Perhaps he had admired the watercolours of earlier voyaging artists. But it was still a joyous shock to behold them: The depth and purity of the colouring [is] marvellous … I was doing what I never thought to, using pure cobalt and emerald green!
Percy Gray was besotted. He had discovered his destiny: Everybody is delighted with the ice, personally it simply fascinates me… At present I am planning to spend most of the rest of my life down here …
Even the old hands were moved, even ‘Gloomy’ Davis: It is full of remembrances, this sighting of the huge bergs. It takes me back to the old Nimrod days, and is still the same wonderful and beautiful sight…
Just as we were about to encounter the ice, we were given a reminder of just how precious it is. The University of the Southern Ocean is in full swing down here on board the Aurora Australis below 60º South. Last night the ANU climate scientist Will Steffen spoke to us about the Anthropocene, the term invented by Nobel Laureate Paul Crutzen for a newly proposed geological era that is characterised by pervasive human influence on Earth processes. In the last 200 years, humans have registered on the earth’s meter as a geological force. We have collectively become an influence on climate that is comparable to the astronomical causes of ice ages.
Antarctic ice cores have been crucial to our understanding of the place of humans in earth history. The cyclical ice ages of the last few million years were probably a significant driving factor in the evolution of modern humans, and the very stable climate of the Holocene (the last 10,000 or so years since the end of the last ice age) has seen the rise of human civilisations. Now the Anthropocene – marked by an alarming loss of biodiversity and by rapidly rising CO2 due to industrialisation – heralds a new era in which ice and human society will both be massively destabilised. Ice may seem abiotic and inhuman but it is bound up with our fate.
With such an understanding of earth history one looks at these icebergs not only with awe but also with gratitude. But also with dread for their – and our – future. The ice is overwhelming in its magnificence and power, and it dwarfs and humbles humanity. Yet the cumulative impact of human society is insidiously undermining it.
Over the hundred years since the AAE, one of the great scientific changes has been the emergence of glaciology as a discipline – it is now a subject of urgent global interest and concern. In many ways this development would have both surprised and delighted Douglas Mawson. Mawson was first drawn toAntarcticabecause, as a geologist, he knew the effect of ancient ice ages on Australian rocks and was excited by the opportunity of seeing an ice age in action. But now ice is a subject of sophisticated study itself, and this particular mineral has been revealed as an archive of the atmosphere. It was ice cores from both Antarctica andGreenlandthat delivered the scary sense of urgency that we now feel about global warming.
The small icecap near Australia’s Casey station (west of us here) called the Law Dome – the lower slopes of which I walked with caution and awe in 2002 – has delivered some unusually discriminating atmospheric narratives. Unlike the rest of the Antarctic sheet, this isolated icecap projects into the easterlies close to the continent and collects substantial precipitation. As a result, the Law Dome ice cores extracted by Australian scientists have produced the most detailed ice climate data available for the last 1,000 years. The frequently expressed hopes of Douglas Mawson and Hubert Wilkins that Antarctic meteorology would assist the understanding of Australian weather, especially the causes of droughts, have been realised dramatically with the recent discovery at the Law Dome of an inverse correlation between precipitation in coastal East Antarctic and southwestWestern Australia. Australian Antarctic Division scientists, Tas van Ommen and Vin Morgan, have united science and the humanities by combining the ice record with the human documentary record to deliver illuminating historical patterns.
If alive today, Douglas Mawson would be out there defending the future of his beloved ice. He would be at the forefront of the scientific effort to explain to the general public the dire implications of the climate crisis.