A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


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Notching up open review improvements – a correction to Part III

Flagging an update (coming) to Big News Part III

Score 1 for open science review, thanks to Bernie Hutchins, an electrical engineer who diligently asked the right questions about something that bothered him regarding the notching effect. We’re grateful. This will improve the model. On the downside, it means we’re slightly less certain of the delay (darn) — the notch doesn’t guarantee a delay as we had previously thought. But there is independent evidence suggesting temperatures on Earth follow solar activity with a one cycle delay — the lag seen in studies like Archibald, Friis-Christainsen and Usoskin is still a lag.

What does it mean? The step-response graph (figure 2 in Part III or figure 4 in Part IV) will change, and needs to be redone. The reason for assuming there is a delay, and building it into the model, rests now on the independent studies, and not on the notch. The new step change will need to be built into the model, and in a few weeks we’ll know how the predictions or hindcasting change. David feels reasonably sure it won’t make much difference to the broad picture, because a step-response something like figure 4, Part IV, explains global warming [...]

BIG NEWS part VI: Building a new solar climate model with the notch filter

The Solar Series: I Background |  II: The notch filter  |  III: The delay  |  IV: A new solar force?  |  V: Modeling the escaping heat.  |  VI: The solar climate model (You are here)  |  VII — Hindcasting   | VIII — Predictions

Open Science live — The story so far: Dr David Evans is building the O-D notch-delay solar model. It’s a much simpler big-picture approach than Global Climate Coupled Models. They use an ambitious bottom-up system where the models add up every small aspect in every small cell of the Earth’s climate atmosphere and oceans and try to predict everything, but the trap is the errors — small errors in 10,000 calculations add up to big-mush. David’s approach is top-down. He looks at the whole system from the outside, and doesn’t try to understand or predict each individual part. It’s a way of starting at the start — to shed light on the big forces and processes that happen as energy arrives on Earth, gets reflected, or blended, and eventually changes the surface temperature. His model won’t tell us what happens to rainfall in Sudan in 2050, but [...]