The findings have just been published in the Journal of Geophysical Research, which means that they have been subjected to searching scrutiny by other climate specialists. The UK Meteorological Office’s Hadley Centre and the Climatic Research Unit (Cru) at the University of East Anglia was able to recalculate climate change data so as to incorporate large numbers of observations from the arctic, which had earlier been sparsely recorded.
Since 1900, the average surface temperature of the earth has increased by 1.4 degrees Fahrenheit, about .75 degrees C., because of the enormous amount of carbon dioxide and soot that industrial society is spewing into the atmosphere. Because of increasing carbon emissions, the earth is likely headed toward a 3-5 degree C. increase (5-7 degrees F.), which will over centuries melt all the surface ice, produce tropical conditions over the entire planet, and cause a sea level rise of dozens of meters/ yards. In the worst case scenario, a third of all land will be submerged.
New research on the Pliocine era has shown that even a 2 degree C. increase will likely cause a sea level rise of as much as 60-70 feet (20-23 meters). .. http://www.blog.thesietch.org/2012/03/19/global-sea-level-likely-to-rise-as-much-as-70-feet-in-future-generations/ .. That would affect 70% of the earth’s inhabitants, hundreds of years down the road. Typically in past geologic eras, a 1 degree increase in average surface temperature produces a sea level rise of 10-20 meters (roughly 30-60 feet). But note that in the Pliocene, a couple of million years ago, the level of carbon dioxide in the atmosphere was only what it is presently (about 390 parts per million), whereas we are moving rapidly toward much higher levels before emissions level off.
Scientists Discover Second Instance Of Global Warming-Caused Mammal Shrinkage
November 3, 2013
Image Caption: An artist's rendering of the early horse Hyracotherium (right) alongside a modern-day horse. Researchers found that Hyracotherium body size decreased 19 percent during a global warming event about 53 million years ago. Credit: Danielle Byerly, University of Florida.
redOrbit Staff & Wire Reports – Your Universe Online
While scientists have known for several years that some mammals became smaller during a period of warming known as the Paleocene-Eocene Thermal Maximum .. http://www.redorbit.com/topics/paleocene-eocene-thermal-maximum/ .. (PETM), researchers from the University of Michigan have found a second instance of mammalian “dwarfing” attributable to increasing temperatures.
During the PETM, which occurred approximately 55 million years ago, mammals such as primates and groups that include deer and horses became much smaller. Now, paleontologist Philip Gingerich .. http://www-personal.umich.edu/~gingeric/ .. and colleagues have found that a second, smaller global warming event, which happened two million years later, had a similar effect – and that discovery suggests a similar phenomenon may also occur as a result of modern-day, human-caused climate change .. http://www.redorbit.com/topics/climate-change/ .
“The fact that it happened twice significantly increases our confidence that we’re seeing cause and effect, that one interesting response to global warming in the past was a substantial decrease in body size in mammalian species,” explained Gingerich, a professor of earth and environmental sciences at the Ann Arbor, Michigan university.
Gingerich and scientists from the University of New Hampshire, Colorado College and the California Institute of Technology (Caltech) presented their findings Friday at the annual meeting of the Society of Vertebrate Paleontology .. http://vertpaleo.org/annual-meeting/annual-meeting-home.aspx .. in Los Angeles.
The study authors discovered decreasing body size appears to be “a common evolutional response” of mammals to extreme global warming events known as hyperthermals, and that these types of physiological changes could be “a predictable natural response for some lineages to future global warming.”
According to the researchers, the period known as the PETM lasted approximately 160,000 years, and during that period global temperatures rose an estimated nine to 14 degrees Fahrenheit at their peak. The second event, which occurred 53 million years ago, was identified as Eocene Thermal Maximum 2 (ETM2) and reportedly lasted between 80,000 and 100,000 years. It resulted in a peak temperature increase of about five degrees Fahrenheit.
“Teeth and jaw fossils of early hoofed mammals and primates that spanned this later climatic event were collected in Wyoming’s Bighorn Basin, and the size of molar teeth was used as a proxy for body size,” the university said. “The researchers found that body size decreased during ETM2, but not as much as the dwarfism seen in PETM fossils.”
For instance, the researchers found that an ancient type of dog-sized horse known as Hyracotherium .. http://www.redorbit.com/education/reference_library/science_1/mammalia/2580164/hyracotherium/ .. experienced a body-size decrease of approximately 30 percent during the PETM and 19 percent during EMT2. Following both events, the creature ultimately returned to its original pre-warming size, and the authors believe the magnitude of the warming event is likely related to the extent of dwarfism experienced by mammals.
Much of modern-day global warming is believed to have been caused by the burning of fossil fuels and the ensuing release of carbon dioxide and other greenhouse gases. The PETM and EMT2 events, on the other hand, could have been caused by the release of seabed methane clathrates, a kind of methane ice found in ocean sediments, Gingerich and his colleagues said. However, this is still the topic of ongoing research.
“Methane is a more potent greenhouse gas than carbon dioxide, and atmospheric methane is eventually transformed into carbon dioxide and water,” the university said, adding “the parallels between ancient hyperthermals and modern-day warming make studies of the fossil record particularly valuable.”
“Developing a better understanding of the relationship between mammalian body size change and greenhouse gas-induced global warming during the geological past may help us predict ecological changes that may occur in response to current changes in Earth’s climate,” noted Will Clyde .. http://earth.unh.edu/clyde/wcc.html , a member of the research team and an associate professor of geology at the University of New Hampshire.
Source: redOrbit Staff & Wire Reports - Your Universe Online
.. a teaparty fringer who is not a creationist, who believes in evolution and in climate science could thunk something like .. 'just think of the medical expense of crook necks suffered by basketball fans if the PETM and the EMT2 events had not occurred' ..
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but some of Eohippus, one of its ancestors, became the hippopotamus, who beat the heat by staying in riparian habitats. So it means the selective pressure of evolution did them well, as diversity became the key to survivability, and odd numbered toed grazers survived in several forms. http://investorshub.advfn.com/boards/read_msg.aspx?message_id=72522369