Scientists have been concerned about climate change for decades. As early as 1965 a science advisory panel to then President Johnson warned that “increasing atmospheric CO2 could lead to marked changes in climate by the year 2000.” The United Nations formed the Intergovernmental Panel on Climate Change in 1988 which relies on input from hundreds of scientists including well known skeptics. Since 1990 the IPCC has issued an updated report every 5 or 6 years. According to the first report, the Earth’s average temperature had risen by 0.5 to l degree Fahrenheit in the past 100 years. It concluded, however, that the increase could be due mainly to “natural variability”. However, by 1995 that possibility had disappeared. The new evidence suggested a “discernable human influence, increased melting in the Greenland and Antarctic ice caps, and the virtual collapse of mountain glaciers around the world. Globally the planet is the warmest it has been in thousands of years, if not more.” “In 2001 the IPCC estimated that global temperatures could rise as much as 5.8ͦ° Celsius by 2100. (Rockford Register Star 1/28 /2007)
Russian researchers returned from western Siberia in 2005 and reported the world’s largest frozen peat bog was quickly melting into ‘”shallow lakes” and was probably irreversible and probably connected to climatic warming. Thus, as much as a billion tons of methane gas (formula weight 16), 20 times more potent than carbon dioxide could be released into the atmosphere. Similar patterns are developing in Eastern Siberia and across parts of northern Alaska. If it continues to thaw scientists think it could produce a “tipping point” of no return in the Earth’s ability to self-regulate (Belvidere Daily Republican 7/23/2006)
According to an article in the Rockford Register Star, (3/5/206) the Antarcticis now showing an ice deficit. The world’s largest reservoir of fresh water is shrinking faster than new snow can fall. Between 2002 and 2005 it lost ice at arate of 36 cubic miles a year. Artic glaciers of Greenland according to researchers at the University of Colorado were melting at a rate twice as fast as five years ago (2001). This amounts to 38 cubic miles of fresh water added to the Atlantic Ocean each year. This suggests that increased global temperatures have altered the seasonal balance of the world’s water cycle (see essay IV). Virtually all measurements are the result of using satellites. Ice shelves are thick plates of ice that float on the ocean around Antarctica. Snow, glaciers, and ice flows feed the plates during “winter” and melt during “summer” in a cycle as old as Antarctica itself. Large icebergs calve off on a regular basis. Most scientists believe that recent increases in calving are linked to warming surface air temperatures resulting from human activities. If this continues, sea level rise would make some densely populated coastal areas uninhabitable. Some 200 million people-in low-lying areas of Vietnam, china, India, and other countries could be displaced. (Belvidere Daily Republican 12/9/2005)
From the October 19, 2008 issue of the Rockford Register Star in an article titled “On thin ice”, the Arctic Ocean is recording record temperatures as the ocean is getting warmer and less salty as ice melts. “Obviously, the planet is interconnected so what happens in the arctic does matter to the rest of the world” said Jackie Richrter-Menge of the Cold Regions Research and Engineering Laboratory in Hanover, N. H. The report involved scientists from 10 countries. The intergovernmental Panel on Climate Control blames human activity for adding carbon dioxide and other global warming gases to the atmosphere. Rising temperatures help melt the ice which in a vicious cycle allows more solar heating of the ocean. The warmed air affects land and marine life and reduces the amount of sea ice that remains into the following summer. Arctic land increases in greenness as shrubs move north into areas that were formerly permanently frozen. Other findings included an unprecedented rate of sea level rise of nearly O.1 inch per year. Also reindeer herds that had been increasing in numbers for years are leveling off or beginning to decline.
The Belvidere Daily Republican’s Earth Talk section of the February 17, 2010 edition contained the following discussion of the world’s oceans changing salinity as polar icecaps continue to melt. Global warming adds fresh water into the oceans. The concern here is that if this continues to happen fast enough, the influx of fresh water could disturb ocean currents enough to change weather patterns on land as well. The Gulf Stream that keeps northeastern U.S. and northwestern Europe warm could stall and shut off some of the worlds highly populated areas natural heating source. This could plunge those areas of two continents in a cold snap that could last for decades or longer. Think of the domino effect that would have on crop and tourism economies. If the salinity of the ocean changes drastically, the water in the warm water stream could instead of getting heavier (which sinks and normally then flows back southward from whence it came completing the cycle) would stall.
The following pictures represent the same exact area of Boulder Glacier, Glacier National Park, Montana from 1932 (left) and 1988 (right) (Gore, A. 2006). Note the difference.
The graph below shows ice core data charting average temperature from the past thousand years.in the Northern Hemisphere. The line at 0.0 represents average temperature from 1961 to 1990. Any year with an average temperature below the 0.0 line was colder than average and is shown in blue; any year with an average temperature above the 0.0 line was warmer than average and is shown in red. I’ll let the reader draw your own conclusions.
At the risk of sending my readers into data overload, I will show you what may be the most important graph of the essay. It compares atmospheric CO2 concentration (blue line) and the Earth’s temperature (gray line) over the past 650,000 years. Do you remember if…then hypotheses from Essay II? Here’s the perfect example of one that can be made? If higher amounts of CO2 are related to higher temperatures, then the blue line and the gray lineshould follow the same pattern. Do they?
The July, 2017 issue of Science Magazine contained this article:A Delaware-sized Antarctic Iceberg Has Broken Into the Ocean
I quote selected paragraphs.
“After months of dangling on by a miles-thin thread of ice, an iceberg roughly the size of Delaware just calved off Antarctica’s Larsen C ice shelf and began drifting out into the ocean.”
“But this trillion ton iceberg, likely to be named A68, was already floating, so it won’t contribute to sea level rise.”
“This ice shelf – a floating patch of ice pushed from a land glacier – is the largest along the Antarctic Peninsula’s coast. The narrow and mountainous peninsula sticks out some 800 miles north from the continent toward Chile. And that location means the region has warmed at least twice as fast as Earth’s overall average.”
“Scientists worry that after this iceberg drifts into the ocean, the shelf behind it might collapse.”
“If the floating Larsen C does collapse, it won’t raise sea levels directly. But once an ice shelf is gone, the glacier feeding it flows faster to the sea. And that will speed up sea level rise.”
Sometime ago in a science class you probably learned that light colored objects reflect light and heat and dark colored objects absorb them. That’s why we wear light colored clothing in the summer and wear light colored clothing at night (unless we don’t want to be seen). I recall a classic demonstration where I would focus a magnifying lens on white paper and then on black construction paper and watch students faces when the black paper smoldered and then burst into flames. Remember as a kid frying ants on the sidewalk with a hand lens? Anyway, my point is that glaciers, because they are light colored, reflect heat back into space but as they melt because of rising temperatures, the darker water or dry earth absorb the heat and speed up the melting thus accelerating climate warning.
Here are some “shorts” on sea ice and glacier melting:
· From 2006, Greenland glacier runoff doubles over past decade.
· The EPA says the sea level along the U. S. coasts are expected to rise 2 feet by 2100.
· In 2005 the glaciers discharged twice as much fresh water as in 1996–enough fresh water to supply Las Angeles for 220 years. (Rockford Register Star)
· From 2007, Artic Sea ice Melting Faster. Newer satellite measurements compared to older model simulations indicate the ice may actually may be shrinking at an annual rate of 7.8 % instead of the original 5.4% which puts it 30 years ahead of the previous predictions. (yahoo News)
References
Rockford Register Star (January 28, 2007) “Washington wakes up to global warming”
Belvidere Daily Republican (July23, 2006) Earth Talk: “How will
Siberia’s thawing affect the world?”
Rockford Register Star (March 5, 206) “Antarctica now showing ice deficit”
Rockford Register Star (October 19, 2008) “On thin ice”
Belvidere Daily Republican (December 9, 2005) Earth Talk: “What are the effects of broken ice shelves”
Belvidere Daily Republican February 17, 2010 Viewpoint, Boyer, G.
Gore, A. (2006) an inconvenient truth Viking, Rodale New York, NY
Science Magazine (July, 2017) “A Delaware-sized Antarctic Iceberg Has Broken Into the Ocean”
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