The White Planet: The Evolution and Future of Our Frozen World

Climate warming has become one of the major challenges that our global society must face. The discoveries made in the ice sheets, notably in Antarctica, have proven this to scientists worldwide. In addition, field data and satellite observations, as well as the viability of the models used for analyzing climate change, have shown us that we cannot ignore this phenomenon. For our part, we have wanted to concentrate on our white planet, whose role in this challenge is crucial since the polar ice is both a unique witness and an essential actor.

Homo habilis, which appeared 2.5 million years ago, then Homo erectus and Cro-Magnon Man had to defend themselves against nature to survive. In that long struggle the paths taken in the migrations of our ancestors were the precursors of our highways. The first human beings fed themselves by gathering and hunting, and then, after becoming more sedentary, they cultivated the land and developed an agriculture adapted to their needs. Animal farming succeeded hunting, and to feed those animals they had to cultivate artificial prairies. We thus entered into the Holocene, a new era for the human way of life but also for the climate which, around 10,000 years ago, was already in a warm condition. To warm themselves and cook food, humans burned wood from forests; with the great leap of the conquest of fire began the still undetectable production of greenhouse gas emissions of anthropogenic origin.

Gradually the landscapes changed. Thus through the millennia humans built structures and cities, visibly reducing the extent of natural spaces. In doing so they disturbed natural geochemical cycles and, beyond the land, our atmosphere was also affected. From wood we moved to fossil fuel, coal, oil, and gas to satisfy the energy demands of a population that was growing

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