Experts predict Lakes to stay high

This March 12, 2019 satellite photo provided by NOAA, shows the Great Lakes in various degrees of snow and ice. A scientific report says the Great Lakes region is warming faster than the rest of the U.S., which likely will bring more flooding and other extreme weather events such as heat waves and drought. The warming climate also could mean less overall snowfall even as lake-effect snowstorms get bigger. The report by researchers from universities primarily from the Midwest says agriculture could be hit especially hard, with later spring planting and summer dry spells. (NOAA via AP)

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We can expect water levels to remain where they are or go slightly higher through the end of the century.

That’s the surprising conclusion in a 74-page report from 18 Great Lakes-based climate scientists published recently by the Environmental Law and Policy Center of Chicago. Their report, An Assessment of the Impacts of Climate Change on the Great Lakes, warns against complacency about the future of the Great Lakes in an area appears to be warming more quickly than other regions of North .

The report predicts impacts on seasonality, habitat loss, pollution and invasive species. These are matters of significance to all of the 3,500 species of plants and animals, including 34 million people, living in the Great Lakes basin.

We’ve heard much of this before as scientists try to explain the consequences of a warming climate. Until now those warnings had included modelling that predicted dramatic declines in Great Lakes water levels so as to dry out huge areas of the lake bed. That part of the climate warming forecast has changed based on the growing body of information, judging by water level sections of the ELPC report.

ELPC, a 15-year-old environmental advocacy group with offices in Washington, D.C., and Chicago, commissioned the review from 18 scientists, including three Canadians, to educate policy makers and the general public. Their report confirms a warming trend since 1901 for the Great Lakes basin, with a mean average temperature increase of 1.6 F, higher than the 1.2 F warming seen in the rest of the United States.

Warmer air holds more moisture and explains the overall observed increase in annual precipitation, the report says. While U.S. precipitation rose more than four per cent between 1901 and 2015, the Great Lakes region saw a 10 per cent increase with more precipitation arriving in unusually large events.

It all means Great Lakes residents can expect wetter winters and springs. We’ll also have slightly drier, hotter summers with a continuing pattern of extreme weather in the form of heat waves, spring floods and even heavier sessions of lake-effect snow and rain. Sound familiar?

For agriculture, the analysis predicts wetter winter and spring conditions will affect planting dates, escalate erosion and subject common corn and soybean crops to later-season drought risk, particularly in southern parts of the basin. Certainly late harvest wetness in 2018 and persistent mould damage to corn fits the forecast.

Regarding water levels, however, general thinking has evolved, although the report also argues this subject also needs better understanding.

The list of authors includes U.S. National Oceanic and Atmospheric Administration analyst Dr. Brent Lofgren, whose Michigan-based lab has specialized in this subject for more than 20 years.

Past modelling overestimated the sensitivity of lake levels to climate change through evaporation, the report says. More recent modelling corrects that and predicts less dramatic changes, describing “small drops in lake levels to the end of the 21st century with an appreciable probability of small rises in lake levels.”

In other words, we can expect more of what we have experienced in recent years since the lakes have returned well above average from the surprising declines of 10 years ago. February data reported in Fisheries and Oceans Canada’s online bulletin, Water Levels, put the monthly mean at 176.83 metres, slightly higher than last year and very near the maximum recorded in 1986 at 177.11 m.

In other words: this is climate change. We’re looking at it.