Nir Shaviv

February 19, 2013 in climate scientist, scientists
Tags: coming ice-age, cosmic rays, cosmic rays and climate change

Nir Joseph Shaviv (Hebrew: ניר יוסף שביב‎, born July 6, 1972) is an Israeli‐Americanphysics professor, carrying out research in the fields of astrophysics and climate science. He is currently an associate professor at the Racah Institute of Physics of the Hebrew University of Jerusalem.^[1] He is also the head of the national coordinating council of faculty unions in Israel.

He is most well known for his solar and cosmic rays hypothesis of climate change.

From his Wikipedia entry

From an online article:

Dr. Shariv’s digging led him to the surprising discovery that there is no concrete evidence — only speculation — that man-made greenhouse gases cause global warming. Even research from the Intergovernmental Panel on Climate Change– the United Nations agency that heads the worldwide effort to combat global warming — is bereft of anything here inspiring confidence. In fact, according to the IPCC’s own findings, man’s role is so uncertain that there is a strong possibility that we have been cooling, not warming, the Earth. Unfortunately, our tools are too crude to reveal what man’s effect has been in the past, let alone predict how much warming or cooling we might cause in the future.

All we have on which to pin the blame on greenhouse gases, says Dr. Shaviv, is “incriminating circumstantial evidence,” which explains why climate scientists speak in terms of finding “evidence of fingerprints.” Circumstantial evidence might be a fine basis on which to justify reducing greenhouse gases, he adds, “without other ‘suspects.’ ” However, Dr. Shaviv not only believes there are credible “other suspects,” he believes that at least one provides a superior explanation for the 20th century’s warming.

“Solar activity can explain a large part of the 20th-century global warming,” he states, particularly because of the evidence that has been accumulating over the past decade of the strong relationship that cosmic- ray flux has on our atmosphere. So much evidence has by now been amassed, in fact, that “it is unlikely that [the solar climate link] does not exist.”

The sun’s strong role indicates that greenhouse gases can’t have much of an influence on the climate — that C02 et al. don’t dominate through some kind of leveraging effect that makes them especially potent drivers of climate change. The upshot of the Earth not being unduly sensitive to greenhouse gases is that neither increases nor cutbacks in future C02 emissions will matter much in terms of the climate.

Even doubling the amount of CO2 by 2100, for example, “will not dramatically increase the global temperature,” Dr. Shaviv states. Put another way: “Even if we halved the CO2 output, and the CO2 increase by 2100 would be, say, a 50% increase relative to today instead of a doubled amount, the expected reduction in the rise of global temperature would be less than 0.5C. This is not significant.”

The evidence from astrophysicists and cosmologists in laboratories around the world, on the other hand, could well be significant. In his study of meteorites, published in the prestigious journal, Physical Review Letters, Dr. Shaviv found that the meteorites that Earth collected during its passage through the arms of the Milky Way sustained up to 10% more cosmic ray damage than others. That kind of cosmic ray variation, Dr. Shaviv believes, could alter global temperatures by as much as 15% –sufficient to turn the ice ages on or off and evidence of the extent to which cosmic forces influence Earth’s climate.

In another study, directly relevant to today’s climate controversy, Dr. Shaviv reconstructed the temperature on Earth over the past 550 million years to find that cosmic ray flux variations explain more than two-thirds of Earth’s temperature variance, making it the most dominant climate driver over geological time scales. The study also found that an upper limit can be placed on the relative role of CO2 as a climate driver, meaning that a large fraction of the global warming witnessed over the past century could not be due to CO2 — instead it is attributable to the increased solar activity.

CO2 does play a role in climate, Dr. Shaviv believes, but a secondary role, one too small to preoccupy policymakers. Yet Dr. Shaviv also believes fossil fuels should be controlled, not because of their adverse affects on climate but to curb pollution.

“I am therefore in favour of developing cheap alternatives such as solar power, wind, and of course fusion reactors (converting Deuterium into Helium), which we should have in a few decades, but this is an altogether different issue.” His conclusion: “I am quite sure Kyoto is not the right way to go.”

How do cosmic rays alter the climate?

According to WUWT and GWPF – “Henrik Svensmark’s hypothesis that most of the global warming of the 20th Century can be explained by the reduction in cosmic rays due to livelier solar activity, resulting in less low cloud cover and warmer surface temperatures”.

Jasper Kirkby of CERN and his 62 co-authors, from 17 institutes in Europe and the USA, announce big effects of pions from an accelerator, which simulate the cosmic rays and ionize the air in the experimental chamber. The pions strongly promote the formation of clusters of sulphuric acid and water molecules – aerosols of the kind that may grow into cloud condensation nuclei on which cloud droplets form. What’s more, there’s a very important clarification of the chemistry involved. [Aug 2011]

Nature who published the research balanced the findings.

It sounds like a conspiracy theory: ‘cosmic rays’ from deep space might be creating clouds in Earth’s atmosphere and changing the climate. Yet an experiment at CERN, Europe’s high-energy physics laboratory near Geneva, Switzerland, is finding tentative evidence for just that.

The findings, published today in Nature¹, are preliminary, but they are stoking a long-running argument over the role of radiation from distant stars in altering the climate.

For a century, scientists have known that charged particles from space constantly bombard Earth. Known as cosmic rays, the particles are mostly protons blasted out of supernovae. As the protons crash through the planet’s atmosphere, they can ionize volatile compounds, causing them to condense into airborne droplets, or aerosols. Clouds might then build up around the droplets.

The number of cosmic rays that reach Earth depends on the Sun. When the Sun is emitting lots of radiation, its magnetic field shields the planet from cosmic rays. During periods of low solar activity, more cosmic rays reach Earth.

Scientists agree on these basic facts, but there is far less agreement on whether cosmic rays can have a large role in cloud formation and climate change. Since the late 1990s, some have suggested that when high solar activity lowers levels of cosmic rays, that in turn reduces cloud cover and warms the planet. Others say that there is no statistical evidence for such an effect.

Outside of the denial-sphere the cosmic-ray effect is considered tiny when compared to CO2. More detail on why cosmic rays are poor at seeding clouds can be found here.