Great lakes ice coverage declines drastically

The Great Lakes are a collection of five freshwater lakes in North America between the United States and Canada. The lakes contain approximately twenty-one percent of the world’s fresh water. Historically the lakes freeze significantly in the winter months, however, recent decades have indicated advancing changes to the region A study recently published in the Journal of Climate indicates that the Great Lakes have experienced drastic declines in ice coverage between 1973 and 2010. Researchers analyzed data provided by the U.S. Coast Guard, satellite images and reports, between these years. The researchers determined that the overall decline in ice coverage of the Great Lakes is seventy-one percent since 1973. Lead researcher Jia Wang from the National Oceanic and Atmospheric Administration points to climate change as a major contributing factor alongside natural climate patterns, such as El Nino and La Nina. Wang stated: “We are seeing the impact of global warming here in the Great Lakes- but the natural variability is at least as large a factor.” Lake Ontario showed the greatest decline in ice coverage, decreasing eighty-eight percent since 1973. Lake Superior also experienced significant declines, seventy-nine percent since 1973. The least impacted lake appears to be Lake St. Clair, which saw a decline of thirty-seven percent. This winter year experts have determined that only five percent of the lakes’ surface froze. This is in contrast to the average forty percent experienced in recent years. 1979 is the greatest for surface freezing in recent recorded history at ninety-four percent. Lake Superior’s Chequamegon Bay is well-known for freezing enough to be driven upon. However, such was not the case this winter and a ferry in the region was operational all year, which has occurred only once prior. There are a number of impacts associated with declining ice coverage, especially for seasons following winter. The decreased ice allows for increased evaporation due to the lack of ice coverage, subsequently causes a drop in water level. Early algae blooms that also have the potential to be more prolific are also an impact of declining sea ice, a situation which has a number of negative side-effects. Shorelines are also in danger of increased erosion due to increased exposure to waves.