One shows reconstruction from cycles only; this has problems getting a good fit in the 1800s but shows rhat the next few years should be a period of reducing temperatures. The long period controlling the plot is 317 year long
The other is constructed round a smooth increasing trend. A better fit in the 1800s and still shows that despite the trend the temperatures will be flat for a few more years before increasing with a vengance. The underlying trend is defined by this polynomial
y = 2.40389E-07x3 - 1.34093E-03x2 + 2.49320E+00x - 1.545547E+03
Do either have any predictive skills. = NO
The most importasnt thing shown is in the the trending plot where despite an ever increasing trend there is still a period where temperatures appear not to increase - from 1998 to 2018. this is due to an underlying 60year period being on a down part of the cycle. This is something that the "skeptics" cannot seem to grasp - CO2 is increasing so why is temperature static?.
The all cycle:
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| 317 year and 60.1 year cycles controlling the "trend"
The trend+cycle plot
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| Trend and 59.75 year cycle controlling trend |
Earlier posts:
http://climateandstuff.blogspot.co.uk/search/label/simulation
hmmph, the mechanism for the c.60 year cycle could be the warm up/cooling down of the ocean above the continental shelves. This might be assumed to change the direction of the heat transfer between benthic depth ocean and the surface layer. Since it's well established that the primary driver of climate change are the greenhouse gases (the change in OLR/ISR), the 60 year cycle might be expected to get shorter as the imbalance in radiation budget gets larger. The deep ocean is pretty uniform so the +300 year cycle should have a different extraplanetary mechanism. Some might assume this could be of solar origin but as the rotation of the sun (at least on the surface) is pretty fast one has to assume that this would happen in solar interior. AFAIK, the astronomers haven't yet demonstrated G-type variable stars with such a long period. So, imo there is a possibility of AMO (linked to PDO) though I'm sceptical of that too and the longer cycle is mathematical play that has no basis in reality.
ReplyDeletethe 300 year cycle is only required to give a profile that currently matches the temperature trends. if a trend is used then there is no need of this cycle.
ReplyDeleteThe 60 year cycle is perhaps a reality (although this whole plot thing is simple wiggle matching!) but again I have no proof of its cause.
What I find interesting is that 0.01C rise in ocean temperature represents a phenominal increase in stored energy. But am I right in assuming that the coupling of this increase into the atmospheric temperature would only cause an increase of 0.01C? So apart from disturbance to sealife is there any problem with ocean temperature increases?
Nice, 317.67 years is the major cycle of Jupiter, Saturn and Uranus.
ReplyDeleteOK and so just what is the physical property of the sum of the periods of 3 planets that causes changes in earths climate.!
ReplyDeleteI do not see how the very small gravitational effects of distant planets can raise the temperature of earth. It isn't the effect on the sun for we have recorded its output reasonably accurately for a few decades and it hasn't changed significantly!