By Scott Harris
For The Chronicle-Journal Oct 12, 2017
THAT’S what they say. Who are they? Well, geophysicist Henry Pollack for one.
In his book A World Without Ice, Pollack explains the delicate geological balance between the Earth and its ice, and why it is important that we humans pay attention to this balance, especially since human activity is accelerating the planet’s race toward a tipping point with respect to its ice.
Ocean floor core samples reveal that the last time Earth was free of ice was 55 million years ago, when the greenhouse gas methane warmed the atmosphere, melting the polar ice sheets and reducing the planet’s ability to reflect solar energy back into outer space.
We currently live in what scientists describe as a Goldilocks environment, not too hot and not too cold. As we look for life on other not-so-fortunate planets, we can see clearly that indeed we are a Goldilocks planet – not too close to the sun to lose all of our water to evaporation, or far enough away to be just another snowball rocketing through space.
Ice ages do come and go naturally, as temporary loans of ocean water to the continents, and vice-versa, have happened 20 times in the last 3 million years. But there is a new player in this tug-of-war, and we humans have at first inadvertently, but lately knowingly, been abetting the ocean team by burning fossil fuels and generating ice-melting greenhouse gases. Satellite imagery and on-the-ground exploration of our ice sheets document this, in geologic time, recent development. Scientists have deemed this era worthy of naming – The Anthropocene, an age in which man’s influence is so dominant that it is changing the Earth’s climate and biodiversity.
NASA documents a 150-year warming trend which coincides with man’s use of fossil fuels to generate energy, the last 25 years of which is at a rate four times greater than the full 150 years, a feverish rate indeed. And this in spite of the fact that solar irradiation is in a cooling period. A rise in CO2 levels from a pre-industrial level of 280 parts per million (ppm) to a current 403 ppm they tell is cause for alarm, and action.
How does this affect the ice-water balance? In the 20th century alone, a mere 100 years, increased glacial meltwater, and the fact that warming ocean water takes up more space than cool water, has meant a 20 cm rise in sea levels. Climate scientists around the world tell us we have “unequivocally” awakened a sleeping giant, and ignore it at our peril. We North Americans per person generate several hundred times the carbon of Takuu Islanders in the South Pacific, yet it is they who have had to abandon their homeland due to rising sea levels as their homes and croplands are awash in seawater.
What would it be like to live in a world without Franklin’s curse, and the Earth’s refrigerant? Words like cataclysmic come to mind, and a flurry of recent hurricanes paint a vivid picture of the vulnerability of even our most modern, North American coastal cities. Hurricane Sandy alone destroyed 350 000 homes!
We know that ice is our planet’s thermostat. More ice, cooler. Less ice, warmer. As geophysicist Carolyn Schoeder states, scientists have done their work. We can see the light, so let’s not wait until we feel the heat.
Alan Weisman, author of The World Without Us paints a wonderful picture of how quickly the biosphere would recover in the absence of humans, the most invasive and destructive superpredator to ever inhabit Planet Earth. Indeed, a world without ice is very likely a world without us. Let’s take care of our ice, so that it can take care of us.
Scott Harris is an environmental activist in Thunder Bay.