Cosmogenic dating ppt
Henrik Svensmark and his team at the Danish National Space Center (DNSC, now DTU Space) submitted a straightforward paper describing their experimental results to a peer-reviewed journal. The main exceptions are the timescales on which the Milankovitch cycles dominate and make other influences very difficult to see.They were stunned when the climate science tsars closed ranks and the paper was rejected. (Milankovitch cycles are caused by variations in Earth’s orbit, not by solar variations.).High-energy particles driven through the laboratory ceiling by exploded stars far away in the Galaxy – the cosmic rays – liberate electrons in the air, which help the molecular clusters to form much faster than atmospheric scientists have predicted.That may explain the link proposed by members of the Danish team, between cosmic rays, cloudiness and climate change.”.In this article, I explore the scientific literature on possible solar indirect effects on climate, and suggest a reasonable way of looking at them.This should also answer Leif Svalgaard’s question, though it seems rather unlikely that he would be unaware of any of the material cited here.So Henrik Svensmark was fully justified in claiming that Cosmoclimatology “is already at least as secure, scientifically speaking, as the prevailing paradigm of forcing by variable greenhouse gases.”. Solar cycle length probably has little to do with GCRs, but I included it here (a) to show that the sun’s effects might not be limited to just GCRs, and (b) to underline the fact that solar influence is harder to see on this timescale.The next step was to publish in a peer-reviewed journal. Correlation of sunspot cycle length with temperature. In total, the papers show that there is overwhelming empirical evidence that solar variation has a major effect on Earth’s climate on virtually all timescales from decades upwards.
In the paper, Jasper Kirkby presented a number of graphs which showed correlations between GCRs and climate. The paper explains how the 14C and 10Be records are independent proxies for GCRs, and how ice-rafted debris relates to climate. The rest of the chain, from there to Earth’s climate, had to be discovered and demonstrated.
Of course, correlation is not causation, but as GCRs are controlled by solar activity the correlations do show a strong relationship between solar activity and Earth’s climate. Correlation of cosmic rays with temperature over the past 500 million years. Note: The GCR flux varies as the solar system passes through the spiral arms of the Milky Way. Correlation of GCR variability with ice-rafted debris events in the North Atlantic during the Holocene. The 2006 SKY experiment at DNSC was aimed at testing the theory that GCRs could cause the formation of cloud condensation nuclei (CCN).
The background to the experiment is explained by Nir Shaviv in his article Cosmic Rays and Climate.
After showing that empirical evidence for a cosmic-ray/cloud-cover link is abundant, he asks: However, is there a physical mechanism to explain it?
In the SKY experiment, the DNSC team set up a cloud chamber to mimic the conditions in the atmosphere, in order to test for the physical mechanism.