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St. James Plaindealer - St. James, MN
  • Climate change may be behind the recent extreme weather events we've experienced

  • Nor can a weatherman predict which way the climate goes. What happens with one day's weather is recorded, perhaps complained about or praised about how great a day it was, and then largely forgotten.
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  • You don't need a weatherman to know which way the wind blows - Bob Dylan.
    Nor can a weatherman predict which way the climate goes. What happens with one day's weather is recorded, perhaps complained about or praised about how great a day it was, and then largely forgotten.
    Climate scientists have a different view of climate change. A new UN report is coming out that says scientists are surer than ever that human activity is causing global warming.
    According to Reuters, "Drafts of the study by the UN panel of experts, due to be published next month, say it is at least 95 percent likely that human activities – chiefly the burning of fossil fuels – are the main cause of warming since the 1950s."
    Unfortunately, the story says scientists are finding it harder than expected to predict the impact of climate change in specific regions in coming decades.
    What we can do is observe and reflect on what is happening with the weather and how climate change is impacting it. My wife and I have been back in Minnesota for a little over four years and in that time there have been a multitude of unusual weather events for our area and Minnesota:
    The snowiest winter on record
    One of the latest frosts on record
    The most intense low pressure storm on record
    All time 24 hour record rain fall
    Record fall flooding
    Minnesota led the nation in the number of tornadoes
    Record tornado outbreak
    A summer of exceptionally heavy rain
    A drought
    Warmest year on record
    Snow in May.
    These types of events suggest we are witnessing and experiencing climate change and the result is we are experiencing more extreme weather events.
    Climate change might be causing a weather pattern known as Arctic amplification. The climate is warming faster at the poles and this is causing large blocking areas of high pressure to cause the normal polar jet stream to meander more to the south and back to the north.
    In the winter of 2010-2011 a system know as a 'Greenland block' of high pressure pushed relatively warm air over NE Canada and Greenland, and that results in bitter Arctic air blasting over us. The other result was that winter was the snowiest winter on record for some areas in southern Minnesota.
    That winter was preceeded by a hard winter in 2009-2010, but spring came early that year and my wife got her garden in on April 1. There were no freezes thanks to an unusually warm spring.
    June and July of 2010 had torrential rains. We had nearly 200 percent of the average monthly rainfall those months.
    Page 2 of 3 - The stormiest day that June was the 17th, when Minnesota experienced an outbreak of 48 tornadoes.
    It was the largest tornado outbreak in Minnesota's history. The state with the most tornadoes in 2010? Minnesota – first time ever.
    September was moderating with mild temperatures and average rainfall, but then on the night of Sept. 22/23 we got 11+ inches of rain, which was most likely an all time single day record for the county. Some locals reported a foot or more of rain.
    The trigger was tropical moisture from a hurricane that went into Mexico and worked its way north and disgorged its moisture on us. Now late September in Minnesota is not the time of year you would expect tropical downpours.
    Here's a summary of this monster storm from the Minnesota Climatology Working Group:
    "The combination of huge rainfall totals and a very large areal extent, make this episode one of the most significant flash floods in Minnesota's climate history. A six inch rainfall total for a given location in this region over a 24-hour period is said to be a 100-year storm. The area receiving six or more inches during this event encompassed over 5000 square miles in Minnesota alone."
    That heavy rainfall caused the Mississippi to hit flood stage in the fall for the first time in recorded history.
    After the deluge it didn't rain for 28 days which is one of the longest dry stretches on record. That dry stretch allowed most farmers to complete their harvest in the fall.
    The next extreme weather event was when we had a monster storm blow over Minnesota with all time record low pressure on Oct. 26-27.
    From the Minnesota State Climatology Office:
    "The weather map for October 26, 2010 showed a large storm system dominating the continental United States. This is one of the strongest non-tropical storms on record for lowest minimum pressure in the United States. The lowest pressure found, after adjusting for the true mean sea level pressure, was 28.21 inches at 5:13 pm at Bigfork in Itasca County. This shatters the old Minnesota lowest pressure record of 28.43 inches that was set in the November 10, 1998 storm at both Austin and Albert Lea."
    After that storm cleared out we got our first frost on Oct. 28, which was very late for a first frost in Watonwan County.
    Then came the snowiest winter and it was so wet the farmers in the spring of 2011 almost needed a boat to plant their crops.
    However, from the middle of 2011 the weather changed. It got hotter and dryer. The winter of 2011-2012 was likely the warmest on record and one of the driest. The average temps in March were off the charts. Farmers and gardners were planting crops in late March. By that time the region was in drought. An abnormally heavy May rainfall of 200+ percent charged the soil to get the crops going. It dried out the rest of the year, though many county farmers got good crops yields.
    Page 3 of 3 - Temperatures mostly stayed above normal until February of this year, when it turned cold. We had an unusual number of snows in April and May. There was state record snowfalls for May hitting just 80 miles east of us. Duluth had it's all time snowiest month on record in April of this year. Some farmers in southeast Minnesota who didn't get much of a crop last year because of drought are not going to get much of a crop this year because the soil was too wet to plant a crop.
    Now scientists are reported to be 95 percent certain humans are mostly responsible for global warming/climate change. Scientists may not be able to accurately predict what is going to happen, but the string of extreme weather events we have experienced in just the last four years suggest we are already witnessing the adverse impact of global warming and climate change. What we've experienced in just the last four years may be an ominous indication of the weather we may face in the future.
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