Guest Post by Willis Eschenbach
In investigations of the past history of cosmic rays, the deposition rates (flux rates) of the beryllium isotope 10Be are often used as a proxy for the amount of cosmic rays. This is because 10Be is produced, inter alia, by cosmic rays in the atmosphere. Being a congenitally inquisitive type of fellow, I thought I’d look to see just how good a proxy 10Be might be for solar activity. Now most folks would likely do a search of the literature first, to find out what is currently known about the subject.
I don’t like doing that. Oh, the literature search is important, don’t get me wrong … but I postpone it as long as I possibly can. You see, I don’t want to be mesmerized by what is claimed to be already known. I want to look whatever it is with a fresh eye, what the Buddhists call “Beginner’s Mind”, unencumbered by decades of claims and counter-claims. In short, what I do when faced with a new field is to go find some data and analyze it. After I’ve found out what I can from the dataset, and only then, do I search the literature to find out what other folks might believe. Yes, it costs me sometimes … but usually it allows me to find things that other folks have overlooked.
In this case, I found a gem of a dataset. Here is the author’s summary:
Annually-resolved polar ice core 10Be records spanning the Neutron Monitor era
Abstract: Annually-resolved 10Be concentrations, stable water isotope ratios and accumulation rate data from the DSS site on Law Dome, East Antarctica (spanning 1936-2009) and the Das2 site, south-east Greenland (1936-2002).
The only thing better than data is recent data, because it is more likely to be accurate, and here we have seven decades of recent 10Be deposition rates (fluxes). So, without fanfare, here’s the data in question
Figure 1. 10Be flux rates from Law Dome in Antarctica and from Southeast Greenland. Bottom panel shows the annual average sunspot count.
So … what’s not to like about these records? Well … lots of things.