Scientists find clues to ice cap longevity: study
"Scientists using DNA extracted from ice buried deep below the surface have found evidence that a lush forest once existed in southern Greenland, a finding that sheds light on how climate change affects Earth's frozen areas.
The researchers analyzed ice cores 2-3 km below the surface from several locations in southern Greenland and discovered what they believe to be the oldest authenticated DNA ever recorded."
"In southern Greenland they found a wide range of plant and insect life, including pine, spruce and alder tries along with beetles, flies, spiders, butterflies and moths, from 450,000 to 800,000 years ago.
Scientists had thought the area was last ice-free about 120,000 years ago during the last interglacial but the study showed southern Greenland was still covered in ice at that time.
This suggests the southern Greenland ice sheet is more stable than thought and might not be as big a contributor to sea level rises caused by rising temperatures, Willerslev said.
This does not change the view that climate change is problematic but could force scientists to rethink their models looking at the impact of warming temperatures, he said."
Hmmm...so, once again, MMGW scientists need to rethink their models...isn't that a surprise. I imagine that the model will go out the window after CERN completes their cosmic ray study. Here's some background for those who mistakenly think the science is settled.
Cosmic rays will create clouds at CERN
"Recent satellite data have revealed a surprising correlation between galactic cosmic ray (GCR) intensity and the fraction of the Earth covered by clouds. If this correlation were to be established by a causal mechanism, it could provide a crucial step in understanding the long-sought mechanism connecting solar and climate variability. The Earth's climate seems to be remarkably sensitive to solar activity, but variations of the Sun's electromagnetic radiation appear to be too small to account for the observed climate variability. However, since the GCR intensity is strongly modulated by the solar wind, a GCR-cloud link may provide a sufficient amplifying mechanism. Moreover if this connection were to be confirmed, it could have profound consequences for our understanding of the solar contributions to the current global warming. The CLOUD (Cosmics Leaving OUtdoor Droplets) project proposes to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. CLOUD plans to perform detailed laboratory measurements in a particle beam at CERN, where all the parameters can be precisely controlled and measured. The beam will pass through an expansion cloud chamber and a reactor chamber where the atmosphere is to be duplicated by moist air charged with selected aerosols and trace condensable vapours. An array of external detectors and mass spectrometers is used to analyse the physical and chemical characteristics of the aerosols and trace gases during beam exposure. Where beam effects are found, the experiment will seek to evaluate their significance in the atmosphere by incorporating them into aerosol and cloud models."
Jeff Kanipe describes an experiment that will be performed at CERN in Switzerland and that will fully start in 2010. The experiment will study the formation of clouds in a C.T.R. Wilson's cloud chamber as a function of the intensity of (artificial) cosmic rays sent from the synchrotron into the cloud chamber at different levels of humidity.
What is the purpose of this toy? There seems to be a disagreement between many astrophysicists, nuclear physicists and related scientists on one side and most climate scientists on the other side. The astrophysicists tend to believe that the Solar and galactic cosmic rays are important to determine the cloud formation and therefore the climate on the Earth. The climate scientists usually believe that the main driver of the climate is something completely different.
CLOUD (Cosmics Leaving Outdoor Droplets) have a chance to resolve this question.
Many arguments have appeared in literature that indicate that the cosmic rays matter. Svensmark and Friis-Christensen of Denmark have argued in 1997 that the cloudiness between 1987 and 1990 declined by 3 percent or so, just like the number of cosmic rays reaching the Earth; the original driver of the cosmic rays intensity were the fluctuating sunspots. This argument has been extended to longer periods of time.
Also, Nir Shaviv, who has a blog, and Ján Veizer - a Slovak-Canadian emeritus professor - have argued that the ice ages in the last millions of years may have been correlated with the motion of the Solar system through the galactic arms which caused variations in the cosmic ray flux. The general mechanism is always the same: higher amount of cosmic rays is supposed to create a higher amount of clouds which should cool the Earth."
Summary of CERN CLOUD (Cosmics LeavingOUtdo or Droplets) Experiment
"In 1997 Svensmark and Friis-Christensen [1] announced a surprisingdisco very that global cloud cover correlates closely with the galactic cosmic ray intensity, which varies with the sunspot cycle. Although clouds retain some of the Earth?s warmth, for most types of cloud this is more than compensated by an increased reflective loss of the Sun?s radiation back into space. So more clouds in general mean a cooler climate?and fewer clouds mean global warming. The Earth is partly shielded from cosmic rays by the magnetic disturbances carried by the solar wind. When the solar wind is strong, at the peak of the 11-year sunspot cycle, fewer cosmic rays reach the Earth. The observed variation of cloud cover was only a few per cent over the course of a sunspot cycle. Although this
may appear to be quite small, the possible long-term consequences on the global radiation energy budget are not.
Beyond its semi-periodic 11-year cycle, the Sun displays unexplained behaviour on longer timescales. In particular, the strength of the solar wind and the magnetic flux it carries have more than doubled duringthe last century [2]. The extra shieldinghas reduced the intensity of cosmic rays reachingthe Earth?s atmosphere by about 15%, globally averaged. This reduction of cosmic rays over the last century is independently indicated by the light radioisotope record in the Greenland ice cores. If the link between cosmic rays and clouds is confirmed it implies global cloud cover has decreased during the last century. Simple estimates indicate that the consequent global warming could be comparable to that presently attributed to greenhouse gases from the burning of fossil
fuels.
These observations suggest that solar variability may be linked to climate variability by a chain that involves the solar wind, cosmic rays and clouds."
:thumbsup:
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