PHOTOS BY GARRY BRANDENBURG Noticeably cooler air temperatures are greeting us this weekend. It is just another sure sign that the earth’s orbital position regarding our Sun has reached a point where daylight hours are less than dark hours, and solar radiation is striking the northern hemisphere at less intense angles. In today’s image of the Iowa River, warmer than the air waters cause water vapor condensation to result in low lying fog over the water. This sunrise view accentuates this phenomenon. In the water of the river, too far away to identify, a flock of migrating shorebirds were settled on a sandbar. However, Great Blue Herons will ply the waters of rivers, streams and pond edges as long as they can, searching for vulnerable small fish, frogs or other morsels. They will even stay into the winter months near open water where they can find it. These views of the fall season are free gifts to careful observers.

Iowa River mood swings are evident this fall. Very low water levels are maintaining a slow flow of about 90 cubic feet per second, a mere trickle in this river’s capability.

Exposed sand bars have been dry enough long enough to allow weedy or willow tree vegetation to grow, turning the sand surface in some areas green. The present river flow elevation at the highway gauging station is 8.77 feet, or 861.87 feet above sea level.

A reading of 8.77 feet is the arbitrary setting by the Corps of Engineers and does not reflect actual river water depth at the point. Actual river water depths across the entire channel are only a few inches. The gauge marker setting allows geologists and hydrologists to monitor the river flow rate at all times by remote sensor equipment.

That data is available on the Corps web site, and the data goes back many decades. For the year 2022, the river’s high flow happened on May 9 when its stage was measured at 15.79 feet, an increase over today’s flow of 7.02 feet. In reality, that meant the river was basically bank full with very little floodplain land inundation.

Since then, the river water levels have continued to drop in response to a lack of rainfall events this year. Most of the water in the river at this time is called base flow by geologists and hydrologists, the slow trickle of water from adjacent soils of the watershed. It is similar to a sponge soaked in water, and if left alone long enough, will lose most of its moisture except for a tiny amount at the base.

In contrast, on July 2, 2014, the highest flood stage record showed 22.25 feet, an increase of 13.48 feet of water over today’s levels. To help put this into perspective, take a long stick that is 13.48 feet long onto a sand bar of the river. Hold it vertically with the bottom right at water level. The top of that stick represents where the water level was in July 2014.

That is a huge amount of water, with extremely strong and fast current, and of course many floodplain roadways closed to traffic. All adjacent low lying lands to the river were flooded big time. That is what happens when those natural cycles of too much rain occasionally take place.

So now, during our semi-drought year, the river is showing us its flip side of the coin, representing too little rain over a long summer. All humankind can do is adapt, take it in stride, and know that these cycles of rainfall events will ebb and flow from high to low and back and forth.

Each year will be different. History has shown us repeatedly how this is possible.

I have noted before in this column what the natural history components are concerning the difference between weather and climate. Weather is the short term “right now” type of happening, and the short term prognostic forecasts accurate to a few days.

Climate, on the other hand, must be assessed on time scales of thousands to millions of years. Geologists have used clues from rock strata, ancient soil profiles, and fossilized vegetation and/or pollen grains to help paint a picture of earth’s long ago natural environments. Those conditions have ranged from very hot and dry, to hot and wet, wet and cold and lastly dry and cold, and all those very long eras of time were measured in millions of years.

Which leads me to note other fallacies of the past with regard to ‘forecasts’ or ‘predictions’ by alarmists that did not pan out so well. For starters, this summer we had periods of hot weather. It enabled talking heads on television to make breathless claims that these were unprecedented times, so called “evidence” according to them that the earth was warming and carbon dioxide was to blame.

Well, they are hoping that if that lie is told often enough that people will believe it is true. They are also hoping that many people will continue to confuse weather with climate.

Has hot weather during recorded history of humankind happened before? Yes. The following have been gleaned by researchers at the Cornwall Alliance and RealClimateScience.com. In the year 627 in France and Germany, springs dried up. Water became so scarce that people died, according to the London Standard newspaper.

The year 879 found European farmers giving up due to hot temperatures and failing crops — likewise in the year 993 and the year 1000. Rivers ran dry. Fish suffered death in huge numbers, and their putrefied corpses were evident.

Men and animals venturing into the sun baked lands during 1022 fell down and died. Dry and hot conditions were recorded in 1189 on the Rhine River. Later recordings on the Rhine in years 1303 and 1304 found those streams to go dry, a most unusual condition.

History repeated itself in Europe in 1615, 1625 and 1718. Air temperatures in the year 1779 in Italy baked the soil, killed vegetables and trees. The year 1846 found Paris, France seeing air temps of 125 degrees.

The Little Ice Age is well documented also, a 300 year time frame during the 16th to 18th centuries when below average winter air temperature froze the rivers of Europe. The Little Ice Age was an anomaly embedded within a longer term warming trend coming out of the last glacial maximum.

The longer term climate trend, however, was to rewarm the earth after the last glacial system was in full retreat. Between those hot dry times and cold wet times were lots of more moderate conditions that in the long run allowed humankind to adapt and overcome. It is what we have to do.

These variations of earth’s climate, from full engulfing glacial maximums to inter glacial warmer times, happened in the northern hemisphere 33 times in the past 2.6 million years. That geologic story is known, and the proof is written in rock layers.

Check out online episodes of geology related to ice age floods to help understand the unstoppable cycles of earth’s climate oscillations. The geologic record opens a fantastic insight into earth’s natural history. Facts matter.

During the next two weeks, tree leaf color will burst with color changes. Take a drive to any county park area, walk the trails, enjoy the scenery and cooler air, and keep a watchful eye out for migrating birds of all sizes and shapes.

I highly suggest an excursion to Grammer Grove Wildlife Area located southwest of Liscomb. This park area has both upland forest and bottomland forests. The Iowa River is at its west boundary.

The valley of the river is a flyway corridor for many species of birds. Raptors in particular are being tallied by avid bird watchers who collect the data of citizen scientists enjoying their hobby.

You should include the roads leading to and on top of Mormon Ridge between Albion and Bangor in your county tour of leaf color.

Mormon Ridge is a landform of geologic origins that separates Minerva Creek from the Iowa River. The two water courses join near the southern point of Mormon Ridge. The ridge has lots of oak, hickory and maple trees growing on its steep slopes.

It will be those species of trees whose leaves will soon brighten the entire region. Mother Nature will put on a show for free. All you have to do is go outside to partake and enjoy fall’s color extravaganza.

We do not have true wilderness areas in Marshall County. Unlike some segments of the Rocky Mountain states with huge blocks of timber, tall mountains, and vast grasslands, what we do have locally can give you a taste of wildness in much smaller settings.

Check out maps and brochures of Marshall County Conservation Areas. You can find almost any type of natural area worth extensive exploration. This leads me to this quote from Edward Abbey.

“Wilderness is not a luxury, but a necessity of the human spirit.”

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.

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