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

The degradation of our environment is one of the greatest challenges facing our society. With an increase in population from 1.6 billion in 1900 to 6.6 billion at the beginning of the twenty-first century, with all of its needs and activities, the impact of humans on the planet is now more than worrisome. That impact is manifest both on a local scale, very close to sources such as the great megacities of the industrialized countries, and on a global scale. To increase our awareness of this and to evaluate the state of the health of our environment, we can examine the polar ice caps, which, despite their apparent purity, contain rich data. In those desert and distant zones, they have recorded the rise of pollution and the global nature of the impacts of our activity, a story that should lead us to serious reflection. Let’s look at a few aspects of this story.

A few centuries ago explorers and naturalists realized that the equator did not represent a border between the Northern and Southern hemispheres. Going to the high latitudes of the two ends of the planet, they observed the flight of the Arctic stern birds migrating with the seasons and sighted the great humpback whale as far as the great South, animals guided who knows how in their flight and their swim. These observations suggested that we have only one atmosphere and one ocean.

For the glaciologist of polar regions, the first unexpected discovery came from the observation of magnificent boreal and southern lights that over the course of a few months went from the nights of the ice sheet of Greenland to those of Antarctica—a phenomenon whose study dates from the International Geophysical Year fifty-five years ago: high-energy particles from the solar wind were channeled by lines of force from the magnetic field that surrounds the Earth, and it was at the poles that they encountered the gases of our atmosphere, creating colored sheets in high altitudes. That magnetic field

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