Glaciers and Global Warming
The melting of glaciers is often cited as evidence mankind is causing global warming through carbon dioxide emissions. A corollary of this is that melting glaciers raise sea levels, which will reach catastrophic levels unless CO2 emissions are reduced. Adding to the massive evidence already refuting these assertions, a recent paper provides more accurate reconstruction of two centuries of previous data “by using many more stations, particularly in the polar regions, and recently processed historic data series from isolated island stations.” The new study is based on monthly mean sea level data from 1807 to 2010. Regarding this new study, well-known meteorologist Anthony Watts wrote “this newest analysis of the most comprehensive data set available suggests that there has been no dramatic increase—or any increase, for that matter—in the atmosphere’s CO2 concentration. [Therefore, there is no evidence of any human influence on sea levels.]” The last sentence, in brackets, is Mr. Watt's.
Two other recent studies conclude that global warming of two glaciers in Antarctica will undermine the entire West Antarctic ice sheet, causing it to collapse and slide into the ocean. The authors contend that the Pine Island and Thwaites glaciers are melting on their undersides due to warm ocean water. As a result, the glacier is no longer held in place, they say. As pieces of the ice shelf break off, the ice behind slides forward. The authors assert “...we find no major bed or obstacle that would prevent the glaciers from further retreat and draw down of the entire basin.” This, they suggest, would raise sea level 10 feet or more in coming centuries.
Dr. Don Easterbrook, geology professor emeritus, Western Washington University, provides an illuminating explanation of why this dire prediction will not come true. With the aid of excellent maps, he provides a useful perspective on the geologic setting, the location of mountains, the drainage patterns and outlets of the two glaciers, and the scale of the size and thickness of the West Antarctic ice sheet relative to the Pine Island and Thwaites glaciers. For example, the East Antarctic ice sheet has more than 90% of the continent's ice; the West Antarctic ice sheet, only about 8 and 1/2%, and the Pine Island Glacier only about 10% of that.
But most surprising—and convincing—is Easterbrook's statement: “The importance of ice thickness is that virtually all of the ice sheet is considerably thicker than the depth below sea level to bedrock, so the ice is grounded and will not float.” He demonstrates this with the graph below accompanied by the following explanation.
“[This] is a profile of the West Antarctic ice sheet from the east coast to the Transantarctic Mts., showing thickness of the ice sheet, sea level, and the subglacial floor. At its deepest part, the subglacial floor is 2,000 m (6,500 ft) below sea level, but almost all of the subglacial floor in this profile is less than1,000 m (3,300 ft) below sea level. The ice is mostly more than 2,500 m (8,000 ft.) thick, sobasic physics tell us it will not float in 1,000 m (3,300 ft.) of water nor will sea water melt its way under the ice.” [emphasis added.]
Easterbrook also notes that “at least half a dozen potential grounding lines may be seen” in the above graph. This refutes the claim “that there is nowhere that the glacier can ground so it will all collapse into the sea.”
A Look at Other Glaciers
A book published in 1926, Climate Through the Ages by C.P.E. Brooks, states “the period from 1600 to 1850 has been termed the 'Little Ice-Age.' There were minor maxima of glaciation about 1820 and 1850; since then the glaciers and ice-sheets have been in rapid retreat in all parts of the world.”Today, 88 years later, the necessity of an adequate historical sample is evident. A website on global warming stresses this: “When examining claims made about glaciers, it is important to have historical data back to at least the early 1900s – otherwise the information is out of context for a climatic assessment. Statements about changes over the last few decades are meaningless without a longer term context...
“Most glaciers around the world (alpine and Greenland ice-sheet glaciers) have been melting as part of the long-term warming trend since the end of the Little Ice Age in the 1700s (although some are actually increasing). The recession of glaciers started long before anthropogenic CO2 levels rose...the recession of glaciers cannot be due to anthropogenic CO2-based global warming...
“The IPCC only needs CO2 for the climate models and only for the northern hemisphere.... The anthropogenic CO2 based theory is based strictly on computer models – the empirical data do not support it.
“The United Nations IPCC was founded in 1988 with the purpose of assessing “the scientific, technical and socioeconomic information relevant for the understanding of the risk of human-induced climate change.” —i.e. it is based on the assumption of “human-induced climate change” – there was no attempt to evaluate the scientific evidence of the cause of the warming....[The IPCC] always makes statements regarding the definite human causation; it has never provided substantial scientific evidence that anthropogenic CO2 is the cause. The only evidence provided is the output of computer models.
This website shows this chart of 169 glaciers with the comment it is “consistent for most glaciers worldwide – the recession of the glaciers started at the end of the Little Ice Age.”
The graph shows the glaciers have been receding since 1750, with the trend accelerating after about 1820. This is long before global industrialization, which didn't get underway until the middle of the 20th Century. The electric light bulb and the telephone hadn't been invented yet. (Thomas Edison wasn't even born.) The first commercial electric power plant was not built until 1881-82. Henry Ford began assembly line production of automobiles in 1913, but by then half of the glacier loss from 1800 to 2000 had already occurred. And 70 percent of the glacier shortening occurred before 1940. Obviously the global retreat of the glaciers was not caused by increased CO2 from factories and automobiles. So it is perhaps surprising that new studies keep springing up trying to blame the melting of glaciers on increases in carbon dioxide emissions. But it should not be surprising in light of the fact the IPCC was founded for the purpose of gathering evidence for “human-induced climate change.”
Measurements were made of the Kilimanjaro icecap in 1912, 1953, 1976 and 1979. Kilimanjaro lost 45% of its icecap between 1912 and 1953. Had that trend continued, those glaciers would already be gone. But the period 1953 to 1976 was a period of global COOLING (minus 0.13 degrees F.)—and Kilimanjaro's glaciers still lost another 21%. Another 12% disappeared since 1976, the lowest rate since 1912. Thus contrary to the hype of the global warming alarmists, Kilimanjaro's icecap melted more slowly in recent decades, not faster.
Moreover, since 1979 we have satellite measurements, which are far more accurate than ground-based measurements and give us measurements at various elevations. At the height of Mt. Kilimanjaro, 19,000 feet, they show a cooling of the Kilimanjaro area of 0.40 degrees F. beginning in 1979. This cooling rate (0.17 degrees F. per decade) is exactly the same as the warming rate 1912 to 1953. Kilimanjaro is just one more example of trying to scare the public with a global warming story that has no basis in fact.
In the journal Nature, researcher Betsy Mason wrote,“Although it’s tempting to blame the (Kilimanjaro) ice loss on global warming, researchers think that deforestation of the mountain’s foothills is the more likely culprit....Without the forests’ humidity, previously moisture-laden winds blew dry. No longer replenished with water, the ice is evaporating in the strong equatorial sunshine.”
Mason's work has since been confirmed by several other researchers.
Ten major ice ages have occurred during the past one million years, and another ten occurred in the prior million or so years. These ice ages lasted about 90,000 years and were separated by warm interglacial periods lasting about 10,000 years. We are currently in the Holocene interglacial period. Since this began about 11,500 years ago, we are no doubt very late in this cycle, after which the earth will again experience an ice age.
Sea levels have fluctuated widely as the ice advanced and retreated in accordance with the 90,000- and 10,000-year cycles. Since the most recent period of maximum glaciation, 18,000 years ago, the sea level has risen more than 300 feet without CO2 emissions from industrialization. A land bridge had existed across the Bering Strait, so it was possible to walk from Siberia to Alaska.
The hype of global warming alarmism claimed the temperatures in the 1990s were “unprecedented” and required drastic limiting of CO2emissions to prevent “catastrophic” global warming. But if we compare the mean temperature of the 1990s to the warmest temperatures of the four prior interglacials, we see the 1990s weremuch cooler than all of these corresponding periods. In fact, all four were warmer than the current one by an average temperature of more than 2 degrees C.
120,000 years ago, during the last interglacial period, the Eemian, global sea level was about 8 m (26 feet) higher than today. Globally, temperatures were 1-2 degrees C. higher, and the water temperature of the North Sea was about 2 degrees C. higher than today.
The climate in Greenland during the Eemian period was about 8 degrees C. higher than today. At the beginning of the Eemian, 128,000 years ago, the ice sheet in northwest Greenland was 200 meters higher than today. It regressed during the warm Eemian period, so by 122,000 years ago that ice sheet had sunk to 130 meters below the current level.
The foregoing facts show that current temperatures, glaciers and sea levels are well within the natural range of fluctuations. Far more extreme climate conditions existed many times in the past without ever causing the catastrophic consequences predicted from the far more modest climate changes we see today or are likely to see in the future. Arguments to the contrary are simply baseless and implausible.
It is also baseless and implausible that carbon dioxide is the “culprit” in global warming and a threat to the future. CO2 is a very weak greenhouse gas and comprises only 0.04% of our atmosphere. Water vapor is a strong greenhouse gas and is responsible for at least 95% of any greenhouse effect. If we could eliminate all of the threat from CO2, we would still have that 95% of greenhouse effect (plus about one percent from minor gases.)
Since the greenhouse effect of CO2 is so minor, all of the computer models assume it will be amplified by water vapor, without which there would be no disaster scenario. But in the many documented periods of higher carbon dioxide levels, even during much warmer climate periods, such amplification never happened. During the time of the dinosaurs, the carbon dioxide levels were 300-500% greater than today. Five hundred million years ago, the level of carbon dioxide in the atmosphere was 15-20 times what it is today. Yet the catastrophic water-vapor amplification of carbon dioxide warming never occurred. Today we're told catastrophe will result if carbon dioxide doubles. But during the Ordovician Period the carbon dioxide level was 12 times what it is today, and the earth was in an Ice Age. That's exactly opposite to the "runaway" warming that computer models predict should occur.
It is also implausible that mankind has a significant—much less a decisive—effect on atmospheric CO2. Of the CO2 that constitutes 5% or less of the greenhouse effect, 97% of that comes from nature, not man. By far the largest source of carbon dioxide emissions is the equatorial Pacific Ocean. It produces 72% of the earth's emissions of carbon dioxide, and the rest of the Pacific, the Atlantic, the Indian Ocean, and the other waters also contribute. Volcanoes, swamps, rice paddies, fallen leaves, and even insects and bacteria produce carbon dioxide, as well as methane, which is a far more potent greenhouse gas than CO2. Termites alone emit far more CO2 than all the fossil fuels burned annually, and plant respiration and decay emit 10 to 15 times more CO2 than termites, according to P. R. Zimmerman of the National Center for Atmospheric Research. Human emissions are trivial to the climate.
So why all the hysteria about controlling global warming? It's really not about global warming at all. It's about controlling people for ideological reasons. It would be futile to campaign against global warming from water vapor. Or the sun. (See my previous posting, “It's the Sun, Stupid.”) But if you can scare the public that global warming is a threat to humanity and the future of the planet because of CO2and industrial progress, they are likely to vote for those proposing “solutions” for controlling people and progress to avert disaster even if it isn't real. Global warming is a way of smuggling collectivist ideology into political power, broadening economic controls, social engineering and effacing individual rights, all under the banner of collective good. The global warming issue is really a political ticket to a dangerous future of centralized control. It is the future version of George Orwell's 1984. If the government says something is “true,” it is, even if it isn't. If it says global warming is occurring, that is “true,” even if it isn't. If it says it is caused by CO2, that is “true,” even if it isn't. If EPA says CO2 must be regulated because it is a health hazard, that is “true” even if it isn't.
It isn't just that the alarmists are trumpeting model results that we know must be wrong. It is that they are trumpeting catastrophes that couldn't happen even if the models were right.--Richard Lindzen, climatologist, MIT professor of meteorology.
[Originally published at American Liberty]