Category Archives: Milankovitch Cycles

A Forecast Of Global Cooing For The Remainder Of The Century


Dr. Norman Page believes that natural cycles of 60 and 1,000 years are the principle drivers of Global climate.  He has recently published a study relating his beliefs.  From that study  “The coming cooling: usefully accurate forecasting for policy makers” I will begin with one of his charts:

Here Dr. Page compares forecasts by the IPCC, another forecaster S. Akasofu and his own.  The IPCC  forecast which you have probably seen many time predicts a global temperature rise of 4C by 2100.  Akasofu is much below the IPCC forecast at about 1C by 2100.  Page’s forecast is for a reduction in global temperature by the year 2100.

Dr Page’s Abstract to this paper lays out the big picture:

“ABSTRACT

This paper argues that the methods used by the establishment climate science community are not fit for purpose and that a new forecasting paradigm should be adopted. Earth’s climate is the result of resonances and beats between various quasi-cyclic processes of varying wavelengths. It is not possible to forecast the future unless we have a good understanding of where the earth is in time in relation to the current phases of those different interacting natural quasi periodicities. Evidence is presented specifying the timing and amplitude of the natural 60+/- year and, more importantly, 1,000 year periodicities (observed emergent behaviors) that are so obvious in the temperature record. Data related to the solar climate driver is discussed and the solar cycle 22 low in the neutron count (high solar activity) in 1991 is identified as a solar activity millennial peak and  correlated with the millennial peak -inversion point – in the RSS temperature trend in about 2004. The cyclic trends are projected forward and predict a probable general temperature decline in the coming decades and centuries. Estimates of the timing and amplitude of the coming cooling are made. If the real climate outcomes follow a trend which approaches the near term forecasts of this working hypothesis, the divergence between the IPCC forecasts and those projected by this paper will be so large by 2021 as to make the current, supposedly actionable, level of confidence in the IPCC forecasts untenable.”

The four basic trends in play here according to Page:

“To summarize, the forecasts which follow rely on four basic working hypotheses. First, the solar millennial activity cycle peaked in 1991+/- as seen in Fig 10 in the Oulu neutron count. Second, the corresponding millennial temperature cycle peaked in the RSS data at about 2004-Fig. 4.Third, the 60 year temperature cycle peaked at about the same time and fourth, Ockham’s razor would suggest that the simplest working hypothesis currently available, based on the weight of all the data, is that the trends from the 990 Millennial peak to the 2004 Millennial cycle peak seen in Figs 3 and 4 will, in general, repeat from 2004 to 3004.”

Those charts are as follows:

Figure 10 has had some enhancements so I am showing you that chart.  Note how the cosmic ray theory/clouds cooling are illustrated.

 

Fig 4. RSS trends showing the millennial cycle temperature peak at about 2003.6 (14)

Figure 4 illustrates the working hypothesis that for this RSS time series the peak of the Millennial cycle, a very important “golden spike”, can be designated at 2003.6.

 

Fig.3 Reconstruction of the extra-tropical NH mean temperature Christiansen and Ljungqvist 2012. (9) (The red line is the 50 year moving average.)

Good view of the 1000 year cycle that Page refers to.

Dr. Page also predicts the next Little Ice Age  will likely occur about 2640+/-

Page’s  study is about 15 pages long but is definitely  worth your time to read it.

cbdakota

Russian Scientists Suggest Global Temperatures Will Drop


There are two recent papers indicating that global cooling will begin soon.    Both studies believe that more cosmic rays in the Earth’s atmosphere will be responsible for reduced global temperatures. The cosmic rays produce lower level clouds which reduce temperatures by reflecting incoming solar radiation back into space.

 

“Cosmic Rays, Solar Activity, and Changes in the Earth’ Climate is by a group of Russian scientists led by Y.I. Stozhkov.  The Paper considers Milankovich theory on global temperatures but dismiss it for this study saying that “…… (Milankovitch) changes happen on a long -term scales and are unlikely to be related to the contemporary process of global warming.”  The three orbital factors in this theory are:

  • the Earth’s orbital eccentricity which changes or 100,000 to 400,000 years
  • the tilt angle of the Earth’s rotational axis which has about a 41,000-year cycle
  • the precession angle changes with periods of 19,000 to 26,000 years

They considered solar luminosity but feel that the changes in total solar irradiation (TSI) are too small to alter average global temperature by no more than 0.05C.

The study also looked at the cosmic  rays.  The team compiled  monthly Δ T* data for the period from 1880 to early 2016.  Using that data, they made a spectral analysis for the same period.  The result is shown on the chart below:     (*Δ T often called the “temperature anomaly”.)

The team looked at cosmic rays versus Δ T and found a relationship.  Cloud formation is a function of cosmic ray presence in the Earth’s atmosphere. That is illustrated from the team’s chart shown below:

The team interestingly does not attribute cosmic ray intensity in the Earth’s atmosphere to solar activity.  The study reports:

“Another influence on the Earth’s climate is solar activity; the main period of its variations is ≅11 years. Despite numerous attempts to find a connection between different solar activity indices and temporal variations in delta T values, no such link has been firmly established.”

Their contribution is —-an increase in cosmic rays in the Earth’s atmosphere will lower global temperature. Thus, leaving the reason the cosmic rays increase or decrease as an unknown. Their Figure 1 seems to suggest they see a drop in global temperature beginning soon and lasting until at least 2060.

 

The second study will be posted next.

cbdakota

Climate Cycles-Part 2 Earth’s Obital Cycles Control Glacial Periods


There are several theories for the cause of glacial periods–Cycles of glaciers followed by  interglacial warm periods and then repeating that cycle. Of those theories, the Milankovitch Cycles theory seems to have a broad base of adherents who believe it to have the best answer that question.   The Milankovitch theory has some weaknesses.  So this posting remains skeptical, however, it appears that there are good reasons why it is probably the most accepted theory.  That Richard Lindzen is a supporter of the theory is one of the good reasons.

The Milankovitch theory says that moving in and out of glacial periods is a result of variation in the Earth’s orbit and orientation.  Three parameters—Earth’s eccentric orbit around the Sun, the planet’s axial tilt and the procession of its axis are the basis of the theory.   These parameters are pretty well defined.   The coincidence with certain combinations of the three parameters and the paleohistory of glacial periods is reasonably close.   A posting by Doug Hoffman on his blog, the Resilient Earth “Confirmed! Orbital Cycles Control Ice Ages” is very good.  I could not say it as well, so this posting  will lift much from his.  

 

From Hoffman’s posting:

Earth’s orbit goes from measurably elliptical to nearly circular in a cycle that takes around 100,000 years. Presently, Earth is in a period of low eccentricity, about 3%. This causes a seasonal change in solar energy of 7%. The difference between summer and winter is a 7% difference in the energy a hemisphere receives from the Sun. When Earth’s orbital eccentricity is at its peak (~9%), seasonal variation reaches 20-30%. Additionally, a more eccentric orbit will change the length of seasons in each hemisphere by changing the length of time between the vernal and autumnal equinoxes. (Click on the Chart to enlarge.)

relisearthEccentricity_Obliquity_Precession-noaa_dlh-500

Variation in Axial Obliquity, Orbital Eccentricity, and Polar Precession.NOAA.

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