60 Year Oscillation

5 May 2018

At https://wattsupwiththat.com/2018/04/26/the-60-year-oscillation-revisited/ ... the 60 year oscillation is an obvious feature in climate data sets - but only back to 1850. Prior to that date it is not so obvious. Javier has posted an article on the 60 year cycle in which he says prior to 1850 it was variable and is not well identified during the Little Ice Age. The reason why may emerge later. A side effect of this situation is that the origin of the oscillation is an unknown - and although it is often said to be associated with the Sun this might not be strictly so. We may also note that it is virtually ignored by the IPCC and modern climate scientists - yet it has a big amplitude. Javier says if this oscillation is considered most of the climate alarmism disappears.

The oscillation was first detected by Folland et al (1984) in global SST and night time marine air temperature records. It was later correlated to precipitation records in the Sahel (Folland et al again, 1986). The multidecadal oscillation was isolated by Schlesinger and Romankutty (1994) in the mean global temperature record as a 65 to 70 year northern hemisphere periodicity. They attributed it to variability in the ocean temperature system. Later, Kerr (2000) called it the Atlantic Multidecadal Oscillation (AMO) and various others have continued to write about it (Scafetta for example).

One novel idea of Javier is that during La Nina periods in the Pacific thermal energy due to higher insolation produced by a reduction in clouds and therefore lower evaporation rates from the ocean surface, has an accumulating potential problem. In amassing lots of heat in the ocean level below the actual surface waters itself it builds up heat which explodes in an El Nino event. This releases the accumulated thermal energy by dispersing it through the ocean circulation system to eventually be lost to space at the North Pole (the South Pole is landlocked). He gives the year of 1876 as an example of what he means. It was a monster of an El Nino which followed a prolonged period of La Nina conditions. This is smack in the middle of the IPCC base line (1850-1900). It was a complete catastrophe and caused terrible multi year droughts and famines - in Brazil, India, China and RussiaIt claimed the lives of 20 + million people (3 per cent of the world's population). As such, the spike affected all oceans and when temperatures recovered the world was able to resume as normal. Javier goes on to suggest a link with luni-solar influences (or orbits), somewhat like certain others (Piers Corbyn for example). Javier points a finger at 9 year periods in lunar tidal frequency. Scafetta also claimed in regard this model that the speed of the earth around the Sun is perturbed by the presence of the Moon at a frequency of 9.1 years. In other words, a 9 year cycle may affect the ocean circulation system. A modulation between the 9 year lunar cycle and the 11 year solar cycle was explored by climate scientist Clive Best a few yeas ago (and came up with no obvious evidence). Javier's post is to bring up the issue once again, in the hope of producing the evidence - by himself as well as fellow posters and commenters. Javier revisits the subject in this article and claims there is a correlation between the lunar and solar cycles (9 and 11 years) but as the solar cycle is not fixed at 11 years (and can be shorter or longer) this has distinct impacts. For instance, the weak signal of a 60 year cycle during the Little Ice Age may be due to a low level of solar activity.