Letters for July 20, 2006

Ice, ice, baby
Re “Don’t believe me? See the movie,” (Right Hook, July 13):

Being a lefty, I disagree with almost every one of Right Hook’s opinions. However, I am grateful that I live in a country where he has the absolute right to state those opinions.

Given that premise, I rarely feel compelled to offer a written response to his columns. However, I must respond to one of his statements in the July 13 column, as it is so unbelievable that a man of his supposed education would make such an asinine factual assertion.

He stated, “I’m quite certain melting polar caps aren’t likely to raise ocean levels any more than melting ice cubes in a soft drink cause the cup to overflow.”

Is he serious? Is he unaware that Antarctica is an actual continent, with an actual land mass below the snow and ice? Is he unaware of the amount of snow and ice that is currently above the water surface at the North Pole? Am I wrong to think that if the snow and ice melts, it will add to the volume of all the oceans, thereby causing the ocean levels to rise?

Please try this simple and easy-to-understand experiment: Fill a cup to the top with ice cubes. Obviously, there will be some room to add some water. Add some water, bringing the water surface to approximately the middle of the cup. Set the cup in the summer sun for two hours. Check the level of the water.

Ted Chrissinger

Uncommon sense
Re “Don’t believe me? See the movie,” (Right Hook, July 13):

Thanks are in order to Lafferty for disproving global warming in a short column with his “common sense” approach to the problem. Since letting the ice melt in your Coke doesn’t raise its level, then letting the icecaps melt won’t raise sea levels either. Clearly, all the thousands of people who’ve been writing about sea levels rising for the last 30 years are idiots without any common sense. Perhaps, though, Lafferty needs a refresher course in common sense, in the form of a simple experiment. Take that same glass of Coke, but let the ice melt in another cup. Then pour it in. Guess what? The level rises! This is the same as what happens when the polar ice caps (which sit on land) melt into the ocean.

As for the glacier that is still advancing and not melting—common sense should tell Lafferty that the temperature in different parts of the world can be different at the same time. Even if the planet as a whole is getting warmer, there just might be places that are cold enough for glaciers. Mike can thank me for the lessons on what everyone else already knows anytime he wants.

Alex Cardenas

Illuminated by science
Re “Don’t believe me? See the movie,” (Right Hook, July 13):

In his July 13 article, Mike Lafferty, in an attempt to portray scientific disagreement over the issue of global warming, cites the advance of the Hubbard Glacier as an apparent contradiction to global warming. His choice of an example could not have been worse and demonstrates his lack of knowledge on the topic of glaciology and global climate change in general. Mass balance studies of glaciers across the world show a net decrease in surface area and volume. In most parts of the world, this is substantial.

Recent studies in Switzerland, for example, estimate an 18 percent loss of surface area from Swiss glaciers between 1985 and 1999 alone. In regions, such as the Karakoram and the Andes, the long-term loss of water resources resulting from a complete melting of the glaciers constitutes a major economic problem. In Alaska, there has been a substantial loss of glacier mass throughout the last 50 years. We know this because of airborne laser altimetry studies that have been conducted since the 1950s. In a recent paper in the journal Science, Keith Echelmeyer and his co-authors estimate the average rate of thickness change from 67 glaciers in Alaska to be –0.52 meters per year.

That may not sound like a lot, but the glaciologists estimate that approximately 9 percent of the global sea level rise is due to Alaskan glaciers melting. These scientific observations are backed by the first-hand accounts of mountain climbers and photographers from all over the world. We have been measuring changes in global temperature and observing an overall loss of glacial ice mass worldwide and sea level rise worldwide. These facts are irrefutable. Furthermore, Mr. Lafferty’s choice of the Hubbard Glacier is a poor one.

The Hubbard is a tidewater glacier, and tidewater glaciers are known to advance and retreat erratically. This is in part due to an effect that saltwater has on the inner workings of the glacier. Small mountain glaciers are far more indicative of climate change because they are susceptible to small fluctuations in climate over relatively short periods of time.

On a final note, the analogy of ice cubes in a glass is a poor one. Most of the world’s glacier ice is not floating, but rather covering the surface of the land. Sea level rise represents the transfer of water from a terrestrial source to an oceanic sink resulting in more water going into the oceans.

Tom Dilts