So why is it we humans like to complain about the daily weather when we are 100 percent unable to do anything about it? Maybe it is our ability to control air temperatures inside homes or business settings where comfort is important to efficient productivity. Then extrapolating that control to the outside environment seems logical but also instantly recognizable as impossible.

We people who are earthbound must adapt to whatever setting we choose to live in. Full time living in tropical settings means heat and high humidity will be a constant companion.

If you live in near Arctic places of the northern hemisphere, summers may get warmer for a short time, however winters are noted for their length, short day lengths and severe cold air masses that seem to linger longer. A mid-continent setting such as the Midwest states means we will experience all the above — hot summertime episodes, milder times mixed with cloudy skies, possible rain events, and then the transition to fall season cooling weather patterns and eventually bring another winter season.

Many species of birds, not all of course, migrate as fall season approaches, in order to find milder climates for overwintering. In those southern states, or Central or South America, warmer air temps and food sources will be available. Some species of birds are year round residents who find berries, fruits or seeds in just the right amounts to survive a Midwest winter.

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Interesting natural history facts about our planet Earth in its orbit around the sun determine our four seasons. The earth’s axial tilt is 23.44 degrees from vertical at the current time. Thus, while in its orbit lasting approximately 365 days, there will be a guaranteed change in the amount of sunlight striking the hemispheres.

While northern hemisphere land masses and oceans get more direct solar radiation during the summer season, southern hemisphere localities get less direct sunlight, thus our summer is their winter and vice-versa. Earth’s axial tilt varies over a 40,000 year long cycle from 21.8 degrees to 24.4 degrees. Those tilt variations have an effect on the amount of solar radiation each hemisphere will receive during one revolution around the sun.

The Earth to sun distance is the farthest away on July 4, a distance of roughly 94,511,923 miles. Scientists have a term for this, and that name is aphelion. Roughly 180 days later on or about Jan. 3, the sun/Earth distance will be closest at 92,955,807 miles.

The name for this fact of physics is perihelion. Why are there differences of distance between the sun and its planets? Because the orbits of the planets, including Earth’s, are not a true circle. Rather the orbit is slightly elongated to form an ellipse. That ellipse is close to being a circle but not quite. It stretches and retreats over solar time scales of about 100,000 years.

A man named Johannes Kepler did the mathematical calculations during the 17th century to take due note of this phenomenon of planet orbital shapes. It turns out that Jupiter’s gravitational pull has a lot to do with planet orbit variations.

Kepler determined that our sun does a little wandering, its rotation being slightly offset from its own center, call it a wobble if you so chose. Astronomers have also noted sun cycles involving surface spots that wax and wane over time.

These have effects on the amount of solar radiation produced by the sun. It may be a mere few tenths of a percentage point, but it does have its effects when light finally arrives at Earth’s surfaces.

In the 1950s, Milutin Milankovich calculated solar energy changes created by sun/Earth relationships. He showed that those solar energy changes were responsible for 75 percent of temperature variations, especially during ice age maximums, and over geologic time, the opposite of ice age minimums.

Milankovich’s work is pivotal to our understanding of climate changes. The fact is that climate changes are primarily determined by natural astronomical influences over which mankind is powerless. The late Tim Ball, retired professor of climatology at Victoria, British Columbia, said it is impossible to detect or separate human effects on climate.

Thus, the false narrative being pushed upon us regarding climate issues is not fact based, but entirely political. The bottom line: facts matter. A study of our sun goes a long way toward finding those facts.

Geologists have been able to put the puzzle together on Earth’s natural history by knowing how to read clues in earth’s rock layers. Other science disciplines add to the bank of knowledge of what happened in the past. For example, during the last 2.6 million years, 33 glacial cycles have happened.

Not all were of the same magnitude or length of stay. Not all interglacial warmer times were equal either. The point is that our Earth responds to solar cycle variations over immense time scales. It is all natural.

Another example goes back 22,000 years ago to the Wisconsinan Ice Age maximum. This was the last glacial maximum, (LGM), for the northern hemisphere that had begun roughly 90,000 years prior.

Canada’s Hudson Bay area was covered by ice more than 6,000 feet thick! That ice sheet covered all of Canada and northern portions of the United States. As that ice slowly melted over thousands of years as the current interglacial time frame re-warming began to dominate, agriculture began in the Middle East 9,000 years ago, while half of Canada was still under ice.

Geologic time scales are truly interesting natural history happenings we can all learn from, and in the discipline of geology, the study of the past helps us understand the future to help solve many Earth history mysteries.

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“If you find a path with no obstacles, it probably doesn’t lead anywhere.”

— Frank A. Clark

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Garry Brandenburg is the retired

director of the Marshall County Conservation Board. He is a graduate of Iowa State University with a BS degree in Fish & Wildlife Biology.

Contact him at:

P.O. Box 96

Albion, IA 50005