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Nick, I want to thank you for contributing your informed point of view.

That doesn't mean I agree with it, but scientific conclusions are at their best when challenged. In fact, the Lockwood paper is clearly a response to a challenge by skeptics who propose an alternate interpretation to the IPCC consensus view, namely that solar effects rather than anthropogenic ones are responsible. That means it is a necessarily narrow piece of research

Being well-read on this but not expert, I'll hazard a response to your critique. Perhaps someone who know more details will also chime in.

The research looks at solar irradiation (heat output) over a short 20 year period.
The paper addresses this. Its point is that if the changes of the last 20 years were to have any effect on the climate, it would be opposite to what has been seen. The only way to explain the opposite effect is to assume a lag time of 50 years for the effect, and that would require a proposed mechanism for the lag.

There is not a correlation.

In fact, there is a correlation, and it's negative. If solar effects were as important as the skeptics are saying, then there would be a correlation, and it would be showing up as cooling.

The conclusion is that there is no solar effect at all.
Yes, that's almost Lockwood's point. The solar effect is so small that it is overwhelmed by other factors acting in the opposite direction.

Well using that approach 1945-1975 (30 years) there is no correlation of global temperatures and CO2. Case proved - no anthropogenic effect.
The problem with that argument is well-known. As power plants were cleaned up, there was much less dust and sulfuric acid droplets in the air. Those had been producing as much or more global cooling as the CO2 was producing warming. Once the masking effects of particulates and acid droplets disappeared, the greenhouse effect asserted itself.

1. You can't ignore other factors.
This research set out to investigate one particular factor. Its results showed and concluded that solar factors pale in comparison to other factors. In other words, it recognized other factors explicitly while focusing on one to study.

2. You can't cherry pick your date ranges.
It didn't cherry pick but started from a point where both solar irradiance and the effect of cosmic rays were at a maximum in their cycle. Because the changes have been in one direction ever since, the effect would be maximized. Both should have led to measurable cooling, but the overall change was warming.

3. If you want to propose no current effect, when the historic effect has been shown (IPCC), you have to put forward the mechanism(s) that have turned the effect off.
The conclusion is that the IPCC overestimated the effect, which it said was minor in any case. This research will be factored into the next IPCC report, along with other research on solar effects. I view this as fine tuning. The major point of the consensus, which is that human activity is the dominant influence on climate change, is strengthened.

Fred Bortz -- Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)