The climate is changing. That is a fact and I would be surprised if there would even be any controversy over the statement.
It has been changing since plates in the earth’s crust moved and continents shifted, earth’s axis tilted, and an enormous number of climate changing events have occurred over the planet’s evolution. I live on a lake that was gouged out by a glacier in relatively recent history.
Right now that lake is gripped in drought as docks will have to be lengthened next spring to reach water deep enough to float boats.
When in Patagonia, Chile on top of a mountain in December I looked down at rocks with vertebrae and fauna visibly imprinted in them. The continental plates are still moving today. I stood in Iceland where the plates are separating and you can stand with one foot in America and the other in Europe.
Again in Patagonia the plates are pushing sedimentary rock that used to be on the bottom of the ocean up into the sky forming mountain peaks. Where there are now glaciers there used to be forests.
Any rudimentary science-based education of the history of climate change on earth would fill volumes of documentation. Some now think that it was climate change as one factor that eliminated the dinosaurs and allowed humans to develop and dominate the earth. I am by no means an expert on the subject, but do know enough to find it fascinating. I am the guy in the family on trips that buys books on the subject.
The climate is changing, continuing to evolve influenced by all the factors, natural and human that impact the change. Time magazine wrote, “If you want to witness climate change in action, just head north.
While the world as a whole has warmed about 1 degree Fahrenheit over the entire 20th century, parts of the Arctic have heated up by 4 to 5 degrees just since 1950.
In 2011, Arctic sea ice shrank to a summer low 1 million square miles below the 1979-2000 average low. (1 million square miles is an area of ice greater than all the U.S. states east of the Mississippi.)
Some scientists worry that Arctic sea ice may be going into a death spiral, unstoppable even if we manage to reduce carbon emissions. And that has consequences for the rest of us – what happens in the Arctic doesn’t stay in the Arctic.”
Last summer, reports emerged that melting in Greenland was accelerating. Research shows, “Its melt rate has grown from about 55 billion tons a year in the 1990’s to almost 290 billion tons a year recently. Greenland is really taking off. Because the world’s oceans are so big, it takes a lot of ice melting – about 10 trillion tons – to raise sea levels 1 inch.
Since 1992, ice sheets at the poles have lost nearly 5 trillion tons of ice, raising sea levels by about a half inch.”
The Antarctic ice sheets are melting too just not at the accelerated rate seen in Greenland. There are glaciers in Patagonia that are still expanding so the ice melt is not universal. Climate scientists do have a sizeable database of historical climate records to compare to. That history includes, quoting the Delta Farm Press, “Tree rings, coral, sediment, and glacial cores, as well as historical records. The Herring Factor is a phenomenon that has been observed for centuries by Scandinavian fishermen who note when herring return to the fishing waters. An early return meant southern waters were warming.”
“The database also shows significant effects on plant life when temperatures change. Tree rings in North America show that small changes in temperature results in major changes in precipitation. And a warm year may have significant implications on the water supply of the western United States. A 1 degree Celsius drop in global temperature is also significant and moves the freeze zone 300 miles.”
That brings us to the more controversial subject of how much of climate change is natural versus man-made. I like ISU Climatologist Elwynn Taylor’s answer to that question. I don’t think that I have ever been to one of his weather outlook meetings without the subject coming up.
He said, “The climate, on its own, does a lot of changing. The weather we have here today is a lot like it was 30 years ago, so in some respects, this is part of a cycle. Then again, humans are doing things that do have some impact on climate and we ought to correct those things.
“We now don’t let Freon go into the atmosphere. Eventually, the atmosphere will cure itself – in about 150 years.” (Continued next week.)
David Kruse is president of CommStock Investments Inc., author and producer of The CommStock Report, an ag commentary and market analysis available daily by radio and by subscription on DTN/FarmDayta and the Internet.
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