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The woes of kilimanjaro: don't blame global warming |
| TheAllINeed.com |
(NC&T/UW) However, two researchers writing in the July-August edition of American Scientist magazine say global warming has nothing to do with the decline of Kilimanjaro's ice, and using the mountain in northern Tanzania as a "poster child" for climate change is simply inaccurate.
"There are dozens, if not hundreds, of photos of midlatitude glaciers you could show where there is absolutely no question that they are declining in response to the warming atmosphere," said climatologist Philip Mote, a University of Washington research scientist.
But in the tropics -- particularly on Kilimanjaro -- processes are at work that are far different from those that have diminished glacial ice in temperate regions closer to the poles, he said.
Mote and Georg Kaser, a glaciologist at the University of Innsbruck in Austria, write in American Scientist that the decline in Kilimanjaro's ice has been going on for more than a century and that most of it occurred before 1953, while evidence of atmospheric warming there before 1970 is inconclusive.
They attribute the ice decline primarily to complex interacting factors, including the vertical shape of the ice's edge, which allows it to shrink but not expand. They also cite decreased snowfall, which reduces ice buildup and determines how much energy the ice absorbs -- because the whiteness of new snow reflects more sunlight, the lack of new snow allows the ice to absorb more of the sun's energy.
 | | A photograph by Edward Oehler taken in 1912 (top) shows the extent of the icecap atop Mount Kilimanjaro, and a similar photo taken in 2006 by Georg Kaser illustrates the icecap's decline. (Photo: U. Washington) |
Unlike midlatitude glaciers, which are warmed and melted by surrounding air in the summer, the ice loss on Kilimanjaro is driven strictly by solar radiation. Since air near the mountain's ice almost always is well below freezing, there typically is no melting. Instead ice loss is mainly through a process called sublimation, which requires more than eight times as much energy as melting. Sublimation occurs at below-freezing temperatures and converts ice directly to water vapor without going through the liquid phase. Mote likens it to moisture-sapping conditions that cause food to suffer freezer burn.
Fluctuating weather patterns related to the Indian Ocean also could affect the shifting balance between the ice's increase, which might have occurred for decades before the first explorers reached Kilimanjaro's summit in 1889, and the shrinking that has been going on since.
Glaciers in more temperate latitudes have declined sharply as the troposphere around them has warmed (the troposphere is the atmospheric layer from the Earth's surface to about 10 miles in altitude). The best example of a glacier declining because of atmospheric warming might be the South Cascade Glacier in Washington state, perhaps the most-studied glacier in North America. Photographs by government scientists in 1928 and in 2000, along with detailed surveys, showed that the glacier lost half its mass during that time. Similar evidence exists for a number of other glaciers, Mote said.
But in their analysis of already published research, Kaser and Mote say the same factors do not apply to Kilimanjaro's icecap, even though its decline has been cited in forums such as the Academy Award-winning documentary film "An Inconvenient Truth."
"There is no evidence to support that assertion," Mote said. "It's not that it is impossible, but rather the decline is most likely associated with processes dominated by sublimation and with an energy balance dominated by solar radiation, rather than by a warmer troposphere."
The volcano Kibo is the highest point on Kilimanjaro, about 19,340 feet above sea level. A rough survey in 1889 suggested that Kibo's icecap occupied about 12.5 square miles. By 1912, more than two decades before Ernest Hemingway wrote his masterpiece short story "The Snows of Kilimanjaro," it had dwindled to about 7.5 square miles. By 1953 it had shrunk to about 4.3 square miles and by 2003 it was at a little more than 1.5 square miles.
The level of nearby Lake Victoria, the world's largest tropical freshwater lake, also declined in the late 19th century, when the decline of Kibo's icecap began. The lake and the icecap likely suffer from a precipitation decline caused by Indian Ocean variability, which also could also have caused the icecap to vary in size and shape over millennia, Mote said.
"It is certainly possible that the icecap has come and gone many times over hundreds of thousands of years," he said. "But for temperate glaciers there is ample evidence that they are shrinking, in part because of warming from greenhouse gases."
How to make your home heating and cooling system cost effective? By: Ophelia Smith
Did your heating bill again knock your socks off? Why not mine? I have a 2100 plus square foot house but my heating system costs only $200 per month. As compared to me, your bill may be even more than $500. Why is there such a big difference? Let's know the basics to minimize this intolerable difference.
When it comes to my house, its visage is southern and obtains a good heat in winter seasons which turns into shade in summer. Most importantly, it is earth sheltered and on ground floor it is heated by propane heater. Additionally I have a wood stove for wintry days and even it is used for cooking whenever power is off. Higher altitude of mountainous location gives my home an appreciable air conditioning for free.
Now let's look on possible problems in your house. First of all your house may be in city where it gets little sun heat. Even though your house might be new and expensive but still I think insulation may be poor. Additionally you may have conventional gas heating and electric cooling system, both of which are expensive. In this way your house is sucking some extra money from your pocket. Obviously most of the houses in US are power controlled. So what you should do to save money? Here are three valuable strategies to do it efficiently.
1. Make sure to use less gas and power in extra efficient systems like air conditioners, hot water heaters and thermostats.
2. Insulation makes a big difference. You should try to increase insulation in structures which are not properly insulated. Cover all cabinets and shelves in the wall with doors. Also build a porch to shade the windows which will serve to save your home from hot sun. Investment in new sheet rock and insulation is required only once but your bill will come every month. Surely these are old ideas but we need to bring these ideas back to save some useful money.
3. While building your house you should ensure good science. Many builders avoid learning and doing something new so they use conventional ideas which are surely sucking our resources. Also poor quality systems are embedded in these extra large and too fragile houses. For this you need to learn all the basics so you become able to ask your builder for a higher quality.
Always remember houses built on small footprints have proved more energy efficient. Experiences have proved that smaller houses are cheaper to have proper heating and cooling system. Another way of proper heating and cooling is to stack the floors over each other. This way they work more efficiently and save some extra money. Similarly, earth sheltering is another useful approach. By this approach the under ground temperature remains 55 degree and it requires only a small amount of heating and dehumidifying. However some of these structures my not need any cooling or heating but still best thing about them is storm and fire resistance capability. Another option can be the addition of solar collectors to your yard and house. The idea of fireplace can be excellent in cold climates to have good heating environment in your house.
Does all this sounds good for you? Surely, if we go for good science rather than fashion, valuable money can be saved to invest some where else!
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| Quotes | Anyone who has never made a mistake has never tried anything new.
Albert Einstein.
Anything that happens enough times to irritate you will happen at least once more.
Tom Parkins Continuum.
Anns my sister, said Andy raggedly.-John Foster
Another 7 days has gone by.
mused Tom weakly.
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