Cry for the cryosphere


Dawson Fagan

The International Panel on Climate Change’s (IPCC) “Special Report on the Ocean and Cryosphere in a Changing Climate” is terrifying, and it has come just in time for Halloween. The report is a harrowing account of sea levels rising and ice sheets melting at a much faster rate than previously anticipated.

Jane Lubchenco, a former National Oceanic and Atmospheric Administration (NOAA) administrator, says, “The ocean is already rising, rising faster than we had predicted. It will continue to rise, and that only serves to underscore the emergency we are confronted with now: The urgency of reducing carbon emissions as rapidly as possible.” Global warming has dramatically affected the oceans because they are a giant carbon sink. Additionally, and perhaps more importantly, they absorb the majority of the heat trapped in the earth’s atmosphere by greenhouse gases.

At a press conference, Ko Barrett, vice-chair of the IPCC, explains, “The ocean has been acting like a sponge, absorbing heat and carbon dioxide to regulate global temperatures, but it can’t keep up.” To put a finer point on it, she says, “The world’s ocean and cryosphere have been ‘taking the heat’ from climate change for decades, and consequences for nature and humanity are sweeping and severe.”

This Special Report is exceptionally terrible because the thing that everybody said wouldn’t happen is happening. The Greenland and Antarctic ice sheets are melting. You know, the ice sheets that were supposed to outlive humanity. The warming atmosphere is, as previously established, heating the ocean and as a result, the ice sheets are melting from the warmth of the ocean that lies deep beneath them. John Mercer first proposed this idea back in the 1970s. As Carolyn Cormann of The New Yorker reports, “In 1990, many scientists still believed that the ice sheet in Antarctica would be stable for thousands of years, even with large amounts of warming. Today scientists are clear that Mercer was right.”

These melting ice sheets are the main contributors to rising sea levels. Valérie Masson-Delmotte, a co-chair of the IPCC, states, “In recent decades, the rate of sea-level rise has accelerated due to growing water inputs from ice sheets in Greenland and Antarctica, in addition to the contribution of meltwater from glaciers and the expansion of warmer sea waters.”

The rising sea-level is a critical part, and arguably the whole point, of this Special Report which proclaims, “While sea level has risen globally by around 15 centimeters during the 20th century, it is currently rising more than twice as fast – 3.6 milimeters per year – and accelerating.” In other words, if we stick below a two-degree Celsius threshold, the oceans will rise somewhere between one and two feet. However, if carbon emissions continue unchecked, coastal civilizations could experience a sea-level increase between two and three-and-a-half feet by 2100.

As it stands, if all carbon emissions were to cease this very moment indefinitely, humans would still be guaranteed a sea-level rise of one foot by 2100. We might even see a three-and-a-half foot increase in our lifetimes. Three feet doesn’t sound like much, but when a hurricane as tenacious as Katrina or Sandy comes along with 25-foot and 13-foot storm surges, respectively, every foot counts when you’re trying to keep breathing.