How Warm And Cold Periods Correlate With Solar Activity, Not CO2 Levels

Written by Dr Jay Lehr

sunset ocean horizon

The climate of the Earth has been constantly changing during its entire 4.6-billion-year history. Variations in our planet’s average temperature due to natural causes have ranged over a span of 60 degrees Fahrenheit.

Most of the periodic temperature increases and decreases observed in human history are consistent with variations in the output of energy from our Sun.

The mild heating and cooling periods seen since 1900 (each less than 2 degrees Fahrenheit) reflect changes in solar activity. The temperature of the Earth has never been constant.

Continental positions determine the distribution and circulation of heat on Earth and have a major impact on our planet’s long term climate.

As little as 70 years ago if a child or adult made note of the fact that our current continents could be fitted together like a jigsaw puzzle, they were laughed at; but in the1950s scientists proved that our continents had historically resided in different places on the globe.

Sometimes the continents were near the equator, sometimes near the poles, sometimes they merged into a single land mass.

The largest changes take place over time periods of 20 to 100 million years. These changes, both gradual and catastrophic are associated with continental motions due to plate tectonics or continental drift.

Periodic changes in the Earth’s orbit also influence how energy that the Earth receives from the sun is distributed, resulting in our current era of recurring Ice Ages.

The Earth is now experiencing the high-temperature end of the latest Ice Age cycle. Both deep-sea sediment and ice core samples show that ice ages take place every 22,000 years.

The Earth’s axis wobbles around a tilt angle of zero degrees in a cycle that requires 22,000 years to complete. At one end of the cycle the North Pole faces the Sun in the winter, while at the other end, the North Pole faces the Sun in the summer.

The tilt angle relative to the sun also varies over a 41,000-year cycle. The annual orbit of the Earth around the Sun cycles between circular and elliptical every 100,000 years.

These are called Milankovitch cycles for the Serbian scientist who discovered them a century ago. Man’s presence and activities are insignificant compared to natural cycles.

Most of the warming and cooling trends observed during human history operate on time scales of a ten to a thousand years resulting in temperature shifts spanning a range of about seven degrees Fahrenheit.

They arise from changes in the output of energy and radiation from our Sun, according to long-term and short-term cycles of solar activity.

These cycles, have been documented using the recorded history of sunspots, aurora observations, radio-carbon dating techniques, and changes in solar radiance.

Changes in solar activity affect the stream of electrons, protons, and alpha particles emitted by the Sun which are called the solar wind.

These changes have been observable in the form of auroras and more recently in the disruption of radio communications and electromagnetic devices.

Changes in average global temperature since 1900 are much more consistent with oscillations in solar activity and the average amount of energy that we receive from the sun than they are with the exponential increase in fossil fuel emissions.

The Earth’s temperature increased from 1880 to 1935 as the Little Ice Age ended. It decreased from 1935 to 1980 and increased from 1980 to 1990 and has since leveled off.

Temperatures did not continuously and dramatically increase to mirror the increasing CO2 emissions.

Read more at CFACT

Comments (5)

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    John Nicol


    This is one of the clearest and most concise explanation of the natural causes of climate change and the Milankovic cycles. Most such explanations also omit the very important aspect of the positions of the continents in determining climate and the interaction between the effects of the Milankoich cycles and the distribution of land and sea.

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    What part of which cycle was responsible for the recent Little Ice Age (LIA)?
    If it was not part of these Milankovitch cycles what did cause the LIA?

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      John Doran


      Changes in cloud cover through low solar magnetic field, as evidenced by low sunspot count?
      The Henrik Svensmark theory?

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        Yes John Doran I wholeheartedly agree.
        My point was to disabuse John Nicol of the idea that Milankovic cycles and the like are the main drivers of all cooling periods.
        The LIA as far as I understand it was not caused by the Milankovic cycles although other seem to think that other cycles interaction (Bray, Gleissburg, Swab etc.) had much to do with it. For instance see here .
        I remain unconvinced as the time variations on these quasi-cycles are as large as +/- 30%, and IMO that’s enough to ‘prove’ anything.

        So basically the question is the same — What part of which cycle(s) were responsible for the recent Little Ice Age (LIA)? In other words what causes the variation in solar magnetic field variation, etc.

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    The fact that at solar minimums the thermosphere shrinks (observed by NASA, and enjoyed by satellite operators). A move that, in all probability, alters the thermal relationships of the atmospheric layers. With Martin Mlynczak of NASA’s Langley Research Center, this is such a big event he and others are implementing the “Thermosphere Climate Index” (TCI)–a number expressed in Watts that tells how much heat NO molecules are dumping into space. During Solar Maximum, TCI is high (“Hot”); during Solar Minimum, it is low (“Cold”). At the end of 2018, the Thermosphere Climate Index is on the verge of setting a Space Age record for Cold.
    At (on the left-hand side info box) the current numbers are:
    Thermosphere Climate Index
    today: 3.52×1010 W Cold
    Max: 49.4×1010 W Hot (10/1957)
    Min: 2.05×1010 W Cold (02/2009)

    And the sun’s ‘small’ decline in output can affect the magnitude of the wind within the Walker cell ( )

    Just these two observations puts paid to the notion that solar variation, certainly at minimums, only has a very small effect on the weather/climate system, it has a major effects.

    In contrast can a minuscule change in the rare atmosphere gas CO2 move masses of the atmosphere, or alter the way the wind blows across a significant area of the planet?
    As far as I can see in 35 years of looking, there is NO observed evidence of such profound changes from the insignificant CO2 variation to do anything like that. In fact there is little to no observed evidence that CO2 affects the atmosphere in any major way, it just encourages plants to green-up the planet.

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