Meteorologist says man not cause of climate issue
Dave Dahl, chief meteorologist at KSTP in the Twin Cities, told Hudson Rotarians that man is not the culprit when it comes to global warming, or climate change, issues.
Dahl spoke to the Hudson Thursday Noon Rotary Club on July 9 and said what was called "global warming" is now tabbed "climate change" because temperatures on the planet have decreased in the past couple years.
"Over 30,000 scientists are now saying that humans are not causing changes in global conditions," Dahl said. "The climate has 'changed' since the planet began."
He said that the heating of the earth -- which is mostly a good thing -- is caused primarily by water vapor -- about 98 percent. He said carbon and other elements account for about 2 percent of the mix. Of that 2 percent, human involvement represents only about 2 percent of that (.0004 percent).
"It is my feeling, and the opinion of more and more scientists, that the sun is the driving force behind climate changes -- heating and cooling," Dahl said. "Solar activity, including flares and sunspots, is usually quite active during warm stretches. The activity has been very quiet the past couple of years and the temperatures have dropped."
He said last year's solar activity was the quietest in 100 years. So far in 2009, the activity is even less.
"In the northern hemisphere, the 2007-08 winter was the coldest in 50 years and 2008-09 was the coldest in a century," Dahl said.
Another flaw in the entire system is the recording of temperatures around the world, he said.
"The United States has the most reputable system, but the recording system in nearly nine out of 10 locations does not meet National Weather Service standards. Many of the sites are located on tar roofs, next to air conditioner exhaust fans, etc. The records are questionable."
He said we should be using only satellite information, which shows that temperatures have been cooling for several years.
"Even believers of man-made 'global warming' have begun to realize that we do not face global warming -- that's why the terminology has been changed to 'climate change,'" Dahl said.
Another key factor in the study of earth temperature is the sequence of events.
"People who believe in man-made global warming claim that an increase in carbon dioxide leads to global warming," Dahl said. "Concrete scientific evidence shows throughout history that temperatures increase first, then carbon levels increase (carbon comes from many sources in addition to man-made pollution). That's contrary to the claims made in the Al Gore movie ('Inconvenient Truth')."
Dahl claims that the Gore movie contains at least 50 factual errors -- he called them absolutely false.
Dahl said that carbon spewed from one of the many volcanoes around the world adds much, much more carbon to the atmosphere than all the cars combined.
"I'm all for limiting pollution, but carbon is not necessarily a pollutant - plants would prefer more carbon," Dahl said.
He noted that there has been much publicity about the shrinking of the polar ice cap.
"Evidence shows that the cap was much smaller in the 1930s when we went through a warm period," Dahl said. "Siberian ice has grown 20 percent in the past two years."
Dahl noted that throughout history there is evidence of warm and cold periods.
"It's a recurring pattern and the sun in the key ingredient," Dahl said. "The fact is, we could very well be headed for a cool period. Some scientists believe we are headed into a 20-30-year cooling trend based on historical patterns."
He said it is unfortunate that the science of climate has been mixed in with political policy and political agendas.
"Many scientists are afraid to speak out because much of the funding comes from the government and they are afraid they will lose funding," Dahl said.
"The political landscape endorses only one view -- that humans are causing global warming. The policy-makers and media drive what people hear. People like to think that we can control our destiny -- this is one thing we can't control. People don't like to hear that."
Dahl hopes that what he considers to be the truth will become evident in the next five to 10 years.