Failure™ Magazine

A World Without Ice

Why ice matters—and how humans are upsetting the delicate geological balance between Earth and this critical component of our environment.

Written by Jason Zasky   Filed under Science & Technology

The sea ice that covers the Arctic Ocean much of the year is also experiencing more summertime melting and breakup. Over the past three decades the summer ice loss has increased, so that compared to the late 1970s, only about 60% of the area and half the thickness of the sea ice remains at the end of the summer. If that rate of ice loss continues for another decade or two, we may see an ice-free Arctic Ocean in the summer, probably for the first time in human history.

Meanwhile, ice at the top of high mountains is in retreat around the world. Many of the tropical and mid-latitude glaciers, such as those in Africa, the Andes, the Alps, and in the Rocky Mountains will probably disappear in the next few decades. Ice loss is also occurring in the Himalayas, but because of their greater elevations and larger ice mass, some ice will endure beyond the end of the 21st century.

Why is Earth’s ice deteriorating so rapidly?
The atmosphere is warming because of the anthropogenic greenhouse effect. The burning of carbon-based fossil fuels emits carbon dioxide into the atmosphere, and enhances the heat-trapping capability of Earth’s atmosphere.

What does the melting of ice mean in terms of sea level rise?
Just as an ice cube afloat in a beverage glass does not raise the water level in the glass as it melts, neither does the accelerating seasonal melting and breakup of the Arctic sea ice raise sea level directly, because that ice is already afloat in the Arctic Ocean. But the melting of Greenland and the mountain glaciers around the world contributes additional water to the oceans, at a rate sufficient to raise sea level approximately 12 centimeters over the course of a century. Such a rise in sea level would on its own be disruptive but not catastrophic.

But melting ice is not the only cause of an increase in sea level. Two other factors play an even greater role. The first is simply the warming of ocean water around the globe, which causes the sea water to expand. This factor alone contributes more than half of the rise in sea level currently observed. The second factor is the direct loss of ice from Greenland and Antarctica directly into the sea, without first undergoing melting. Such additions of ice raise sea level the moment the ice discharges into the sea. The glaciers draining ice from Greenland and West Antarctica have been accelerating their discharge in the last two decades. Currently, sea level rise from all causes is at a rate of 34 centimeters per century. Were Greenland to return all its ice to the ocean, sea levels would rise a little more than seven meters. Such a rise would be catastrophic.

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