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 II: For the first time – a mysterious notch filter found in the climate

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

This is the first of many posts. It is primarily about the entirely new discovery of a notch filter, which electrical engineers will immediately recognize, but few others will know. Notch filters are used in electronics to filter out a hum or noise. You will have some at home, but everyone seems to have missed the largest notch filter running on the planet.

This post is also about the broad outline of the new solar model. It’s a O-D (zero-dimensional) model. Its strength lies in its simplicity — it’s a top down approach. That solves a lot of problems the larger ambitious GCMs create — they are a bottom up approach, and effectively drown in the noise and uncertainty. This model does not even attempt to predict regional or seasonal effects at this stage. First things first — we need [...]

Fourier Analysis reveals six natural cycles driving temperatures, no man-made effect: predicts cooling

Thermometer circa 1790

UPDATED: Post note below, with a couple of extra caveats…

Lüdecke, Hempelmann, and Weiss found that the temperature variation can be explained with six superimposed natural cycles. With only six cycles they can closely recreate the 240 year central European thermometer record. There is little “non-cyclical” signal left, suggesting that CO2 might have a minor or insignificant effect.

The three German scientists used Fourier analysis to pick out the dominant cycles of one of the longest temperature records we have. The Central European temperature is an average of records from Prague, Vienna, Hohenpeissenberg, Kremsmünster, Paris, and Munich.

The dominant cycle appears to be about 250 years. There is also a cycle of about 60 years, corresponding to the Atlantic/Pacific decadal oscillations.

Data is of course, always the biggest problem. If we had 10,000 years of high quality global records, we could solve “the climate” within months. Instead, we have short records, and Lüdecke et al, make the most of what we have. The European records are only 240 years long, or (darn) one dominant cycle, and only one region, so to check that the results are valid over longer periods they also analyze a the 2000 year Spannagel Cave [...]