What's the link between cosmic rays and climate change?
What the science says...
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Cosmic ray counts have increased over the past 50 years, so if they do influence global temperatures, they are having a cooling effect. |
Climate Myth...
It's cosmic rays
"When the Sun is active, its magnetic field is better at shielding us against the cosmic rays coming from outer space, before they reach our planet. By regulating the Earth’s cloud cover, the Sun can turn the temperature up and down. ... As the Sun’s magnetism doubled in strength during the 20th century, this natural mechanism may be responsible for a large part of global warming seen then." (Henrik Svensmark)
The galactic cosmic ray (GCR) warming hypothesis is based on the premise that GCRs can "seed" clouds, and clouds reflect sunilight. So if there are fewer GCRs reaching Earth (because a strong solar magnetic field is deflecting them away), the hypothesis says there will be fewer clouds, more sunlight reaching the Earth's surface, and thus more global warming.
So more solar activity means a stronger solar magnetic field, which means fewer GCRs reaching Earth, which hypothetically means fewer clouds and more warming.
The body of scientific research has determined that GCRs are actually not very effective at seeding clouds. However, the hypothesis is also disproven just by examining the data. Over the past five decades, the number of GCRs reaching Earth has increased, and in recent years reached record high numbers. This means that if the GCR-warming hypothesis is correct, this increase in GCRs should actually be causing global cooling over the past five decades, and particularly cold temperatures in recent years.
On the contrary, while GCRs are up, global temperatures are also way up, and temperatures in recent years reached record highs.
Annual average GCR counts per minute (blue - note that numbers decrease going up the left vertical axis, because lower GCRs should mean higher temperatures) from the Neutron Monitor Database vs. annual average global surface temperature (red, right vertical axis) from NOAA NCDC, both with second order polynomial fits.
Last updated on 4 October 2015 by dana1981. View Archives
This may help explain some of the changes that are not explained by the orbital curves in the other thread, especially the initiation of warming and cooling since the GCR effects can be much more powerful (partly forcing as postulated in the paper, but also amplification of the weaker orbital forcing).
- We will investigate the clustering of trace gas molecules onto ions. The trace gas molecules will either be formed by the ionising particle beam in pure artificial air or be introduced directly into the chamber.
- Aerosols of a well defined size and with typical atmospheric composition (NaCl, (NH4)2SO4, H2SO4) can be produced with standard aerosol generation techniques (Section 4.4.3). Experiments will be performed to examine the activation of these aerosols into cloud droplets.
- These experiments will first quantify the poorly-known production rates of a) nitric oxide (NO) and b) hydroxyl radicals (OH) by cosmic radiation. The former will involve pure artificial air and the latter will involve argon and water vapour. Subsequently we will investigate the effects of these vapours on the nucleation and growth of aerosols.
- These studies concern the formation of ice nuclei in supercooled vapours at low temperatures. The expansion chamber will be used to create a supercooled cloud by expansion and growth of drops at temperatures below 260 K. ... In addition to experiments with supercooled liquid droplets already present(freezing nucleation),we will also investigate ice nucleation without pre-existing droplets(deposition nucleation).
- These experiments concern the deposition nucleation of nitric acid and water vapours onto ion clusters to form nitric acid hydrates. Particles composed of such hydrates are thought to be the principal component of the polar stratospheric clouds that initiate the destruction of ozone.
So, in a nutshell, nothing earth shattering in any direction can come from current CLOUD experiments. They are necessary first baby steps to creating a plausibly complete GCR theory (which in and of itself shows how sicence-fictiony the theory is at its current stage). Which means, in a nutshell, that the deniers are getting their undies all in a bunch over nothing, just because they love to crywolfconspiracy.