Will temperatures on Earth be dropping until the year 2100 to Little Ice Age levels, as Horst-Joachim Lüdecke, a scientist at Germany's Saarland University, predicted last week? Or will the temperatures only plunge until 2060, as Habibullo Abdussamatov, the head of Russia's Pulkovo Observatory, recently predicted? Or has the cooling already begun, and might it end as soon as 2030, as claimed by Anastasios Tsonis, head of the Atmospheric Sciences Group at the University of Wisconsin?
These scientists and others who are now warning of global cooling have something basic in common -- unlike scientists who warn of global warming, who often rely on the Earth sciences and blame climatic change on man-made carbon dioxide, the global cooling scientists more often rely on meteorology, solar science and other disciplines that view the Sun, cosmic rays and Earth's orbit as the dominant factors in our climate.
"The Sun, not man, warms the Earth," an earlier article by Lüdecke, concisely expresses the emergent view that humans play an inconsequential role in climate change. The accumulation of evidence from scientists relying on celestial rather than man-made explanations for changes to the global climate has led even the BBC, an ardent advocate of the man-made global warming theory, to credit the Sun.
"Real risk of a Maunder Minimum 'Little Ice Age,'" stated a BBC headline in October, in reporting the view of Mike Lockwood, Professor of Space Environment Physics at Reading University's Meteorology Department, that "solar activity is now falling more rapidly than at any time in the last 10,000 years."
By the standard of recent years, global cooling predictions and natural explanations for climate change are controversial, even outlandish. By the broader standard of the last century of science -- and the centuries that preceded it -- what's outlandish is attributing massive changes in climate to increases in carbon dioxide, a trace gas that represents so miniscule a fraction of our atmosphere that it must be measured in parts per million. Established science had historically held natural forces to drive climate.
The about-face in the established science came not from a change in the science but from a change in the establishment, in the form of the United Nations bureaucracy. When the UN created the Intergovernmental Panel on Climate Change in 1988, it was mandated to examine man-made causes. This mandate led the IPCC to refuse to consider the Sun's influence on Earth's climate as a topic worthy of discussion, as scientists learned at a 1992 IPCC meeting of delegates from around the world. To the surprise of the Danish delegation's Eigil Friis-Christensen, head of the Danish Meteorological Institute's geophysics division, he was not allowed to present the findings of a peer-reviewed article he had co-authored in Science magazine that compellingly correlated sunspots and global temperatures.
Only evidence of man-made climate change would be considered by the IPCC, he and the others in attendance were then told. And for all intents and purposes, he soon learned, only research into man-made causes would in future be funded, published and given credibility. Friis-Christensen and others conducting research into the role of the Sun found their work ridiculed, marginalized and starved of funding. To a remarkable degree, the IPCC establishment succeeded in controlling which works would be accepted for publication, which careers would be assured and which would be cut short.
What the IPCC couldn't control was the climate. Although carbon dioxide emissions have continued their ceaseless rise, temperatures have not followed along in lockstep, as the global warming models had predicted. Instead, temperatures peaked in the late 1990s and have since plateaued at those levels. Even advocates of the global warming hypothesis - including James Hansen, Al Gore's guru -- acknowledge that global temperatures stopped rising.
The global warming scientists -- with their models defunct and now acting on hope rather than science -- assert that temperatures will soon renew their climb. The global cooling scientists assert the opposite - that temperatures on Earth have peaked, as they have peaked countless times before in following nature's cycles. And that consistent with Earth's history, and with the laws of physics, temperatures on Earth will now be falling.
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Researchers in Britain have found that <a href="http://www.bbc.co.uk/news/science-environment-22076055" target="_blank">climate change could cause increased turbulence</a> for transatlantic flights by between 10 and 40 percent by 2050. (ALEXANDER KLEIN/AFP/GettyImages)
A 2012 study from the U.S. Forest Service found that without "major adaptation efforts," parts of the U.S. are likely to see "<a href="http://www.treesearch.fs.fed.us/pubs/42363" target="_blank">substantial future water shortages</a>." Climate change, especially for the Southwest U.S., can both <a href="http://thinkprogress.org/climate/2013/02/25/1638541/study-climate-change-dry-up-us-reservoirs-lake-powell-lake-mead" target="_blank">increase water demand and decrease water supply</a>.
Research by British government found that <a href="http://www.huffingtonpost.com/2013/03/15/somalia-famine-climate-change_n_2883088.html" target="_blank">climate change may have contributed to a famine in East Africa</a> that killed between 50,000 and 100,000 people in 2010 and 2011. At least 24 percent of the cause of a lack of major rains in 2011 can be attributed to man-made greenhouse gases, Met Office modeling showed. (TONY KARUMBA/AFP/Getty Images)
The <a href="http://www.guardian.co.uk/environment/2013/mar/25/frozen-spring-arctic-sea-ice-loss" target="_blank">dramatic and rapid loss of sea ice in recent years</a> has consequences beyond the Arctic. Scientists have found the melting shifts the position of the Jet Stream, bringing cold Arctic air further south and increasing the odds of intense snow storms and extreme spring weather.
Research indicates that increased levels of atmospheric carbon dioxide <a href="http://www.onearth.org/blog/poison-ivy-climate-change" target="_blank">result in larger poison ivy plants</a>. Even worse, climate change will mean that the plant's irritating oil will also get more potent.
The <a href="http://www.livescience.com/28320-climate-change-allergies.html" target="_blank">spring 2013 allergy season could be one of the worst ever</a>, thanks to climate change. Experts say that increased precipitation, along with an early spring, late-ending fall and higher levels of atmospheric carbon dioxide may bring more pollen from plants and increased mold and fungal growth.
North American alligators require a certain temperature range for survival and reproduction, traditionally limiting them to the southern U.S. <a href="http://www.slate.com/articles/health_and_science/animal_forecast/2013/02/alligators_in_virginia_climate_change_could_be_pushing_cold_blooded_species.single.html" target="_blank">But warming temperatures could open new turf</a> to gators with more sightings farther north.
High in the Peruvian Andes, parts of the world's largest tropical ice sheet have melted at an unbelievable pace. Scientists found that significant <a href="http://www.nytimes.com/2013/04/05/world/americas/1600-years-of-ice-in-perus-andes-melted-in-25-years-scientists-say.html" target="_blank">portions of the Quelccaya Ice Cap that took over 1,600 years to form have melted in only 25 years</a>. (Perito Moreno Glacier pictured)
Along with other agricultural impacts, <a href="http://www.huffingtonpost.com/2013/04/08/climate-change-wine_n_3039673.html" target="_blank">climate change may have a dramatic effect on the world's most famous winemaking regions</a> in coming decades. Areas suitable for grape cultivation may shrink, and temperature changes may impact the signature taste of wines from certain regions.
Thanks to climate change, <a href="http://www.guardian.co.uk/sustainable-business/blog/polar-arctic-greenland-ice-climate-change" target="_blank">low-lying island nations may have to evacuate</a>, and sooner than previously expected. Melting of the Greenland and west Antarctic ice sheets has been underestimated, scientists say, and populations in countries like the Maldives, Kiribati, Tuvalu and others may need to move within a decade.
Warmer winters in northern latitudes could mean <a href="http://www.cbc.ca/news/technology/story/2013/01/18/hamilton-climate-change-rinks.html" target="_blank">fewer days for outdoor hockey</a>. An online project called RinkWatch aims to collect data on the condition of outdoor winter ice rinks in Canada and the northern U.S. and educate people on the impacts of climate change.
Experts speculate that <a href="http://news.nationalgeographic.com/news/2010/08/100806-oyster-herpes-global-warming-climate-change-science/" target="_blank">warming oceans may have played a part in a strain of herpes</a> that has killed Pacific oysters in Europe in recent years.
As Arctic ice melts and polar bears see more of their habitat disappear, the <a href="http://www.huffingtonpost.ca/2013/03/14/polar-bears-turn-brown-climate-change_n_2878684.html" target="_blank">animals could lose their famous white coats</a>. Researchers have already witnessed polar bears hybridizing with their brown cousins, but note that it would take thousands of years from them to adapt themselves out of existence.
Climate change means warmer winters in northern latitudes and a shorter ski season. By 2039, <a href="http://www.nytimes.com/2012/12/13/us/climate-change-threatens-ski-industrys-livelihood.html" target="_blank">more than half of the Northeast's ski resorts</a> will not be able to maintain a 100-day season, according to the New York Times. Ski areas will be less likely to receive regular snowfall, and warmer daily low temperatures mean fewer opportunities for snowmaking.
Apples produced in one Himalayan state of India are already losing their taste and even turning sour, experts say. <a href="http://zeenews.india.com/news/eco-news/arunachal-apples-losing-taste-due-to-climate-chang_831169.html" target="_blank">Increased rainfall and erratic weather in the region mean less than ideal conditions</a> for famously-sweet Kashmiri apples.
With climate change already impacting northern latitudes, <a href="http://www.nytimes.com/2013/02/06/sports/warm-weather-forces-changes-ahead-of-iditarod-race.html" target="_blank">warmer winters in Alaska could mean less than ideal conditions</a> for the famous Iditarod sled dog race. “It definitely has us concerned,” a musher and Iditarod spokeswoman who's already breeding dogs with thinner coats told The New York Times.
<a href="http://news.nationalgeographic.com/news/2012/11/121108-climate-change-coffee-coffea-arabica-botanical-garden-science/" target="_blank">Climate change may dramatically shrink the area suitable for coffee cultivation</a> by the end of the century and cause the extinction of Arabica coffee plants in the wild. Starbucks has already declared that "<a href="http://www.starbucks.com/responsibility/environment/climate-change" target="_blank">Addressing climate change is a priority</a>."
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