As in the past, we will resist raising the issue of potential reasons for warming temperature trends only to say that regardless of cause, the current trends represent a mixed bag of results for the health of northern Michigan’s forests, waters and wildlife.
In a recent article appearing in the Petoskey News by Morgan Sherburne, meteorologist Andy Sullivan confirmed that 2012 was the warmest year on record for four northern Michigan communities: Sault Ste. Marie, Houghton Lake, Alpena and Traverse City. In this instance, “on record” dates back to the 1880’s and early 1900’s. In spite of the longer term trend which has seen the Great Lakes region warm by two degrees since the 1980’s, 2013 is not expected to be as warm as 2012 (according to State climatologist and Michigan State University professor Jeff Anderson).
It is likely way too early to proclaim victory again for this year’s Winter Severity Index (WSI) for northern Michigan’s white-tailed deer herd. However, given that we are half-way through January and many parts of our region are only now getting measurable accumulations of snow, the stage is being set for another good year of winter wildlife survival.
The limited snowfall and prolonged open water is not going to help our ever-lowering Great Lakes’ water levels, however. When we last discussed this issue back in July, the level of Lakes Huron and Michigan were 577.5 above sea level. According to the Detroit District office of the Army Corps of Engineers, January 18, 2013 levels are now down to 576.0 feet above sea level. With lake elevation data dating back to 1918, that level eclipses the prior record low of 576.1 recorded in 1965.
Under the heading of “it could have been worse,” river and stream temperature monitoring data revealed that despite the high summer temperatures our worst fears were not realized, at least not where trout were concerned. According to MDNR Fisheries Biologist Tim Cwalinski, in-stream temperature logging data collected over the past summer revealed that those northern Michigan streams with reasonable levels of ground water recharge generally saw temperature levels which were not significantly higher for prolonged periods than those of other recent years.
Cwalinski believes that at least some of this relief was due to the drought-like conditions which resulted in few evening and overnight warm rain events. This rain normally limits a river’s ability to cool overnight and essentially traps the daytime heat-gain. This is not to suggest that a continuation of these weather patterns poses no threat to our cold-water fisheries, only that other conditions relating to fishery recruitment and survival were likely to have had a greater impact than did daytime air temperatures.
Fascinating stuff, but recalling Oscar Wilde’s quote that “conversation about the weather is the last refuge of the unimaginative,” we’ll leave it at that.