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Next Generation Farming

Mother Nature's Mid-life Crisis

This year's strange weather has us wondering: Is it connected to global warming?

The weather in 2009 has left more than a few of us scratching our heads and wondering if Mother Nature has been going through a volatile midlife crisis.

Spring started the year off as a nightmare with planting dragging on due to non-stop rain. The summer that followed was one of the coldest and wettest on record. And now we're ending the year with the slowest harvest on record due to the uncooperative weather. At this rate, harvest will drag on into spring for some who haven't finished yet.

The story of our mercurial weather isn't over yet, though.

The month of October was the third coldest on record nationally. Last week, the northern and western halves of Kansas achieved new record-low temps. Farther south, Houston was hit with a snow storm that was not only a record setter in being the earliest in history for the city, it was also the first time ever they received snow in two consecutive years.

Add all this up, and it ultimately brings us to the inevitable question: Is this global warming?

Admittedly, it's extraordinary that I've come to this question, considering I've been a solid believer in the theory that mankind has played a huge role in our current climatic circumstances. But now, I'm as confused as a cat spinning in a drier.

Snowfall in Houston, Texas, which occurred Dec. 5, 2008 - earliest on record.

If we're in the middle of a warming trend, then why are we setting new records in the opposite direction? Wouldn't that be an indication of a cooling trend?

To help me get it straight, I needed someone who could give me a definite answer. I spoke with one of the most trusted names in meteorology - Peter Leavitt, renowned agricultural meteorologist and president of Weather Information Co., in Newton, Mass.

Peter's view of global warming is pretty straightforward: It's a colossal scam.

"Temperatures have been rising, but most of the rise can be attributed to normal climate variability," Peter says.

It's getting warmer Temperatures have been rising since the end of the last Ice Age about 12,000 years ago, and peaked around 1000 A.D. at levels that were even warmer than they are today. A little Ice Age followed from around 1400-1600, and then ended in the early 1800s. Temperatures began rising significantly again at the beginning of the 20th Century and into the 1940s, at which point they changed direction and began cooling through the 1970s.

Frightened over the change in climate, National Geographic even ran a front-page article warning of the pending Ice Age.

But by the mid-1970s, temperatures started rising again, peaking just around the turn of the new century.

"In other words, man's influence is small. Does he have any influence? Yes, he probably has some," Leavitt says, pointing to the increase in global CO2 levels over the last few decades. "But the impact has been very slight. It's not enough to be concerned about."

CO2 levels are currently around 388 PPM (0.0388% of the atmosphere), up from 315 PPM in 1958, Peter says. The principle greenhouse gas, though, isn't even CO2. It's water vapor, which is 1-4% of the atmosphere. Furthermore, water vapor is many times more efficient at trapping heat than CO2. The increase in the CO2 level, whether from man or any other contributing source, has had only a negligible effect on global temperatures.

So the real source of the change climate?

"The real control of climate takes place in the oceans," Leavitt says, pointing out that changes in Pacific Decadal Oscillation readings in the Pacific Ocean coincide with the changes in the atmosphere.

PDO readings were positive during the 30-year warming trend starting in the 1970s, but are now turning negative, which may lead to a decline in temperatures in the U.S. (Recall the bizarre weather we had this past year? We may have more of it in 2010 if the trend continues.)

So as Peter explains it, the increase in world temperatures and CO2 levels since the 1970s is purely coincidental. The answer lies in the oceans.

Consequently, our climate is never static, Peter says, and will continue to oscillate despite any of man's contributions.

"Trying to stop climate change is like trying to eliminate the tide," he says.

That's quite a relief. Now we don't have to feel bad about not owning a Prius anymore. We'll stick to driving pick-ups on the farm.

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