The Rising Tides of Climate Change

The Earth's glaciers--they're melting!

There’s a classic scene from the Wizard of Oz where Dorothy throws a bucket of water on the wicked witch and the viridian villain screams, “I’m meeeeel-tiiiiiing!”

That currently is what's happening on Earth, except the witch is the world’s glaciers and the bucket of water is climate change. Most controversies about climate change boil down to this:
1. Global warming is happening. Is it part of a natural cycle or a manmade event?
2. Glaciers worldwide are melting and the sea levels are rising. How quickly is this happening and what will the impact be?

Some studies track actual melting over time and others use models to predict melting—the latter being somewhat iffy. That’s why studies modeling sea-level rise vary in their predictions for this century from 12 inches to 5 feet, 3 inches. The fact is that not all study models hold true over time. Take the following:

• The accelerated melting of the Greenland ice sheet will form a lubricating film under the ice sheet, causing it to slip more rapidly into the sea. False. Recent studies show that instead of that occurring, that higher volumes of meltwater form distinct channels under the ice, draining the water more efficiently and reducing the formation of lubricating film
• Himalayan glaciers will disappear by 2035. False. In January 2010, scientists on the United Nations (UN) climate science panel made that erroneous prediction. They have retracted it

What do we know about glacial melting?

• About 21,000 years ago, sea levels rose almost 400 feet. That occurred when a thaw at the end of the last Ice Age released vast amounts of water that had been frozen on land. Sea levels stabilized about 2,000 to 3,000 years ago, with "no significant change from then until the late 19th century," according to the Arctic Monitoring and Assessment Program, a 2007 report by the Intergovernmental Panel on Climate Change (IPCC), the UN climate science panel
• During the 20th century, sea levels rose about 7 inches. Since 1993, rates have accelerated to about 0.12 inches per year, according to the IPCC
• The Antarctic and Greenland ice sheets get the most attention from scientists and the news media because they comprise 99 percent of the freshwater ice on our planet, according to the National Snow and Ice Data Center
• Ice sheets are defined as being larger than 20,000 square miles, and only exist in Greenland and Antarctica, while ice caps are areas smaller than 20,000 square miles and exist at high elevations around the world
• The Antarctic ice sheet measures approximately 5.4 million square miles, and the Greenland ice sheet measures 650,000 square miles
• Sea levels would rise 20 feet if the Greenland ice sheet melted and 200 feet if the Antarctic ice sheet melted

"What is surprising is this increased contribution by the ice sheets is already happening. If present trends continue, sea level is likely to be significantly higher than levels projected by the United Nations Intergovernmental Panel on Climate Change in 2007."—Eric Rignot, lead author, National Aeronautic and Space Administration (NASA) study

What is happening with the Antarctic and Greenland ice sheets?

Greenland is melting fresh water into the sea.

The temperature of the Antarctic Peninsula has increased by 4.5 degrees fahrenheit since the 1950s, according to the National Snow and Ice Data Center.

The Greenland and Antarctic ice sheets are losing mass at an accelerating pace, according to a recently released, 20-year NASA-funded satellite study that tracked actual melting. Here's what they found:

• In 2006, the Greenland and Antarctic ice sheets lost a combined mass of 475 gigatons (gigaton=one billion metric tons or 2.2 trillion pounds) a year on average. That's enough to raise the global sea level by an average of .05 inches a year
• The pace at which the polar ice sheets are losing mass is accelerating rapidly. Each year over the course of the study, the two ice sheets lost a combined average of 36.3 gigatons more than they did the year before
• Even the vast and frigid East Antarctic ice sheet is losing some of its mass to the oceans
• If current ice sheet melting rates continue for the next four decades, their cumulative loss could raise sea level by 5.9 inches by 2050. When this is added to the predicted sea level contribution of 3.1 inches from glacial ice caps and 3.5 inches from ocean thermal expansion, total sea level rise could reach 12.5 inches
• Extending this glacial melt to 2100, the sea level could rise 22 inches

A study led by Richard Katz of the University of Oxford and colleagues, observed the Pine Island glacier at the edge of the West Antarctic ice sheet. Among their results:

• In 2004, satellites showed that it had started to thin, and that ice was flowing into the Amundsen Sea 25 percent faster than it had 30 years before
• Data released in January 2010 suggested that the Pine Island glacier had probably passed a critical "tipping point" and was irreversibly on track to lose 50 percent of its ice in as little as 100 years, significantly raising global sea levels

"The glaciers have lost a lot less ice up until 30 years ago than had been thought. The real killer is that the rate of loss has gone up 100 times above the long-term average. It's scary."—Professor Neil Glasser, Aberystwyth University, United Kingdom

Why should we care about ice sheets and ice caps melting?

• Flooding: About 70 percent of the world’s population lives in coastal areas. Rising seawater would result in the submergence of many island nations in the Pacific and Indian oceans and low-lying countries like Bangladesh and the Netherlands. It would also flood many major coastal cities including New York City, Buenos Aires, London and Bangkok
• Dying ecosystems: The Ward Ice Shelf once contained a unique freshwater lake. After it splintered due to melting, the lake and the ecosystem it contained drained into the Arctic Ocean. As a result, polar bears, seals, walruses and whales were forced to migrate to different regions in search of food. This made it difficult for native people to hunt these animals, thus making it more difficult for them to survive, according to the Natural Resources Defense Council



Heat map of the Gulf Stream currents off of North America.

• Changed ocean/weather patterns: Ocean circulation modeling studies suggest that the increasing flow of fresh water into the Arctic Sea could ultimately weaken or switch off the Gulf Stream, according to PlanBEconomics.com. The Gulf Stream is a powerful, warm, and swift Atlantic ocean current that influences the climate of the east coast of North America from Florida to Newfoundland, and the west coast of Europe. The whole process could theoretically occur very rapidly, in the space of just a few decades or even several years
• Extreme weather: The polar ice caps reflect 80 percent of the sunlight that strikes them back into space. If the ice caps disappeared, this same sunlight would be absorbed by the ocean, raising its temperature. Warmer ocean temperatures would lead to frequent and more intense weather events, according to The Harvard Medical School Center for Health and The Global Environment

How do we grapple with global forces?

From the studies currently out there, it is difficult to assess why the Earth is getting warmer. All we can say for certain is—it is. It is also tough to predict how quickly the sea levels will rise. All we know for sure is—they will. It is time for governments to stop debating what is causing global climate change. It doesn't matter. It’s here. Time would be better spent preparing for the eventuality of coastal flooding, water shortages and extreme weather conditions, if indeed, one can truly prepare on a massive scale for such things. Anything else—at this point—amounts to nothing more than futile, opportunistic posturing.