Groundbreaking Work on the Sun’s Influence on Earth’s Precipitation

The story starts with Professor John Kleppe’s work in 2003 studying ancient trees rooted in the bottom of Fallen Leaf Lake in the Tahoe basin.   Professor Kleppe found that by studying tree ring data and carbon dating that the trees started growing in the lake in the medieval period at about the year 1,000. This led to a now accepted theory that the trees rooted in the bottom of the lake grew during a drought that lasted for over 200 years. But the question remained, what caused the drought?

We now have an answer: “We have shown in several previous papers the major driving forces of winter precipitation in the Sierra are the reversal of the sun's magnetic field and a statistically independent "carrier" signal being generated by the Earth's large-scale atmospheric circulation.”

The solution to this problem is very complex because of the interaction between sun and earth phenomena. It’s important to understand what the modulating factors are that are modifying our climate.

  • The Gleissberg Cycle (GC) with a period of approximately 30-100 years and a Hallstatt cycle of about 3,000 years that modulates the GC.
    • The Earth’s large-scale atmospheric circulation driven by parameters including orbital (inclination, eccentricity, precession, obliquity, and rotational), depth of the atmosphere, and heating by the sun.
  • The reversal of the sun’s magnetic field every 11 years. Many people have postulated that the sunspots are the influencing factor but it is in fact the sun magnetic field reversal and the Gleissberg modulation.


These three signals combine to effectively modulate the Snow Water Equivalent (SWE) of the Sierra Nevada snow pack. In other words, the snow pack is determined by the combined effect of these three phenomena. The Gleissberg modulation is like the amplitude modulation of AM radio communications.

El Nino/La Nina Events

The research also shows how solar magnetic activity affects atmospheric circulation in the western tropical Pacific including the connections between the El Nino-Southern Oscillation (ENSO), the Walker circulation, and the resulting variability in the lower thermosphere. “Researchers continue to search for the connection between the variability of the sun and that of the Earth's troposphere to the point it has become "third-rail science", (Zhai, 2017), (Leamon et al., 2018). The main problem has been the scientific community continues to attempt to directly correlate Earth's climate with the 11 and/or 22year solar cycles.” The Kleppe/Brothers research shows that the Gleissberg modulation has to be included in the spectral analysis to detect the effects of the 22 year sun magnetic cycle.

“The modulation of the sea surface temperature (SST) by the reversal of the magnetic field of the sun comes from the modulation of the downward short wave solar radiation flux, SW↓ and the downward long wave radiation solar flux, LW↓. The SW↓ flux leads the El Nino Modoki Index (EMI) index by one month and the long wave radiation flux LW↓ also leads the EMI index by 1 month. It is important to note the time series of the radiative fluxes are correlated with the time series of the El Nino and the EMI indicating both radiative flux variations have the same solar spectral peaks.” This important discovery shows that El Nino/La Nina events are directly related to the reversal of the sun’s magnetic field thus the snow pack in the Sierra Nevada is dependent on the magnetic activity of the sun.

 

Estimated MRSWE (blue) 1755 to 2031 b. Actual(black) v Estimated(red) for 1913 to 2020 (R=0.7)

 

   Top: Estimated PDSI (blue) 1755-2031 with selected drought dates shown Lower: Estimated PDSI (blue) actual PDSI (red) Correlation: 0.63

PDSI (Palmer Drought Severity Index) Note that the Gleissberg modulation of the sun’s magnetic field model accurately detects the extreme droughts of the 1920’s and 1930’s. The model shows excellent correlation with R=0.63.

It appears Earth's Water Cycle is being modulated by seawater evaporation directly related to solar activity modulated UV light. The maximum transmission of UV light in seawater occurs at the Earth's equator due to the favorable angle as the sunlight enters the seawater. The underwater trapped heat at the longer wavelengths heats the surface seawater and adds to the El Niño effect or "warm water tongue". This idea is supported by the fact the four solar activity generated periods found in the Mt Rose SWE are also found in the Sea Surface Temperature (SST) measurements.”

 

“The reconstruction of Mt. Rose SWE (red) over the period CE 972 to CE 2031, clearly shows the mega-drought reported in (Kleppe, et al ,2011). The midpoint is CE 1155. The solar modulation data from (Brehm, et al ,2021) are shown in blue.”

“It is important to note the solar modulation data (blue) shown in Figure(5) is not directly correlated with the reconstructed SWE(red). One must use the amplitude modulated Kleppe/Brothers model to estimate the SWE. It is also important to note the mega drought CE(1052-1258) is not seen using the model if one ignores the Hallstatt Cycle. The mega droughts appear to occur at the peak values of the Hallstatt Cycle. These values are at the peaks of the absolute value of the demodulated Hallstatt Cycle or approximately every 1586 years. The next mega-drought in the central Sierra is therefore not expected to occur until approximately the year CE 1175+1586 = CE 2761. This should provide sufficient time for appropriate measures to be taken to help mitigate such a wide-spread natural disaster.

Short-term prediction of drought using the Kleppe/Brothers model is limited by the ability to accurately predict the date of the flip of the magnetic polarity of the sun and to also have an accurate prediction of the intensity of the sun’s changing magnetic field over each Solar Cycle.”

Over 20 years of research has been done to develop this theory and these results. It clearly shows that the sun has a very large influence on our climate in a new and novel way that has not been previously investigated. The records have been reconstructed over 1,000 years and correlated to modern times from CE 972 to CE 2031. The high correlation of the effects of the magnetic field of the sun in the Sierra Nevada is better than anything that has been produced by the IPCC modeling initiative.

Conclusions

We noted that there was little correlation between the IPCC models and the warming period of the early 20th century. The Kleppe/Brothers research has shown very high correlation (R=.7) between the amplitude modulation of the sun’s magnetic field by the Gleissberg Cycle, and the Mount Rose, NV snow water equivalent (MRSWE) record over water years 1913-2021.  There is still much more research to be done to better understand how solar cycles affect the earth's climate.