Wednesday, August 31, 2016

Cosmic Rays Intensity Increasing

New Study Suggests Sun More Important Than Thought On Earth’s Climate
 
Cosmic rays have been steadily increasing in recent months during historically weak solar cycle 24 

This colorized picture of the sun is a mosaic of ultraviolet images from the orbiting TRACE satellite sensitive to light emitted by highly charged iron atoms. Growing in number, the intricate structures visible are the Sun's hot active regions with temperatures over a million degrees Fahrenheit and their associated magnetic loops (courtesy NASA) 

We happen to be in a weak solar cycle (24) which is actually on pace to be the weakest cycle in more than one hundred years. Therefore, it would not be surprising to have relatively high cosmic ray penetration into the Earth’s atmosphere; especially, since we are now heading towards the next solar minimum phase when solar activity is generally even quieter. In fact, for the past year, neutron monitors around the Arctic Circle have sensed an increasing intensity of cosmic rays. Polar latitudes are a good place to make such measurements, because Earth’s magnetic field funnels and concentrates cosmic radiation there. As it turns out, Earth’s poles aren’t the only place cosmic rays are intensifying. “Spaceweather.com " has led an effort in the launching of helium balloons to the stratosphere to measure radiation, and they find the same trend increasing intensity of cosmic rays over California. -- Paul Dorian, Vencore Weather, 29 August 2016

A team of scientists from the National Space Institute at the Technical University of Denmark (DTU Space) and the Racah Institute of Physics at the Hebrew University of Jerusalem has linked large solar eruptions to changes in Earth’s cloud cover in a study based on over 25 years of satellite observations. The new study, published in Journal of Geophysical Research: Space Physics, shows that the global cloud cover is simultaneously reduced, supporting the idea that cosmic rays are important for cloud formation. The eruptions cause a reduction in cloud fraction of about 2 percent corresponding to roughly a billion tonnes of liquid water disappearing from the atmosphere. The Suns contribution to past and future climate change may thus be larger than merely the direct changes in radiation, concludes the scientists behind the new study. --Technical University of Denmark, 24 August 2016

computer models suggest that if the Sun really is heading for a new Maunder Minimum, there will be a cooling effect, but it won’t be big enough to halt global warming. As for a new mini ice age, that seems highly unlikely. On the face of it, this is good news all round. While there’s no need to panic about a big freeze any time soon, the Sun may at least be giving us more time to deal with global warming. Yet that’s not how some scientists see it. They seem to regard this new twist to the climate change debate as a threat, opening the door to “denialists” who dismiss global warming as scaremongering. The experiences of one solar physicist suggest these academic guardians of the faith are keen to stop the idea of a less active Sun getting any traction. Evidence is the most powerful guide we have in the science of climate change. But if that evidence is censored or twisted, the science becomes mere sound and fury, signifying nothing. -- Robert Matthews, The National, 28 August 2016

The habit of some scientists of predicting when the ice will disappear completely keeps getting them into trouble. A Nasa climate scientist, Jay Zwally, told the Associated Press in 2007: “At this rate, the Arctic Ocean could be nearly ice-free at the end of summer by 2012.” Two years later Al Gore quoted another scientist that “there is a 75 per cent chance that the entire north polar ice cap, during the summer months, could be completely ice-free within five to seven years” — that is, by now. This year Professor Peter Wadhams of Cambridge University has a new book out called Farewell to Ice, which gives a “greater than even chance” that the Arctic Ocean will be ice-free next month. Not likely. He added: “Next year or the year after that, I think it will be free of ice in summer . . . You will be able to cross over the North Pole by ship.” The temptation to predict a total melt of the Arctic ice cap, and thereby get a headline, has been counterproductive, according to other scientists. Crying wolf does not help the cause of global warming; it only gives amusement to sceptics. --Matt Ridley, The Times, 29 August 2016

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