great lakes

Little ice on the Great Lakes

March 8, 2024 By EarthWise Leave a Comment

In an average year, the Great Lakes end up about 40% covered in ice. But this is not an average year. 2023 was the warmest year on record and, in fact, the global temperature was more than 1.5 degrees above the pre-industrial average for the full year. That hasn’t happened before. As a result of the record-breaking warmth, as of mid-February, the average ice cover on the Great Lakes was only 5.9%.

Lake Erie and Lake Ontario tied their records for the lowest ice cover, which has been tracked since 1973. Lake Huron, Lake Michigan, and Lake Superior are at historic lows. Some parts of the Great Lakes have experienced the winter without any ice cover.

The warming air temperatures have led to rapid ice loss and warming summer temperatures. According to experts, if the planet continues to warm, more than 200,000 lakes may no longer freeze every winter and 5,700 lakes may permanently lose ice cover by the end of the century.

Studying the Great Lakes is important because their ice melt can be a significant indicator of the progress of global warming. Decreasing ice cover can affect hydropower generation, commercial shipping and fishing, and have environmental impacts such as the development of plankton blooms.

Since the 1970s, there has been a 5% decline in Great Lakes ice cover per decade. Unfrozen lakes bring more rain than snow which has environmental, cultural, and societal impacts. The Great Lakes hold 21% of the world’s freshwater supply and over 30 million people depend on them for drinking water. They are also linked to over $3 trillion in gross domestic product.

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Web Links

Great Lakes Winter Ice Cover Averaging Just 5.9%: NOAA

Photo, posted November 7, 2007, courtesy of Jim Sorbie via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Attack of the giant goldfish

January 15, 2024 By EarthWise Leave a Comment

Goldfish are just about the easiest pets to keep. A species of carp native to East Asia, they have been bred to look pretty and are generally little more than home décor. We keep them in little glass bowls and feed them mysterious flakes out of a container. With these confined quarters and meager meals, they remain small, harmless creatures. But released into the wild, it is a very different story.

People dump pet goldfish into lakes and ponds with some frequency. Once they are in the wild, these humble creatures can grow to monstrous proportions. They can eat nearly anything, including algae, aquatic plants, eggs, and invertebrates. They can kill off native marine wildlife and damage or even destroy fragile and economically valuable ecosystems.

For a few years, Canadian researchers have been tracking invasive goldfish in Hamilton Harbour, at the western tip of Lake Ontario, about 35 miles southwest of Toronto. That part of the lake has been decimated by industrial and urban development as well as by invasive species.

Goldfish were first spotted in the harbor in the 1960s, mostly died off in the 70s because of industrial contamination, but then recovered in the 2000s. Goldfish can tolerate a wide range of water temperatures, reach sexual maturity quickly, and can reproduce several times in one season. In resource-rich places, they can grow up to 16 inches long, making them too large a meal for many predators.

There are literally millions of goldfish in the Great Lakes and not only there. Feral goldfish are a problem in Australia and in the United Kingdom. Invasive species are a big problem, even if they start out small and cute.

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Web Links

Once They Were Pets. Now Giant Goldfish Are Menacing the Great Lakes.

Photo, posted September 20, 2015, courtesy of Watts via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And Allergies | Earth Wise

March 23, 2021 By EarthWise Leave a Comment

According to a new study published in the Proceedings of the National Academy of Sciences, an addition to the many hardships that climate change is causing around the world is the fact that it is making allergy season worse.

Researchers have found that there is a strong link between planetary warming and pollen seasons. The combination of warming air and higher levels of carbon dioxide in the atmosphere has caused North American pollen seasons since 1990 to start some 20 days earlier, on average, and to have 21% more pollen.

The most pronounced effects were seen in Texas, the Midwest, and the Southeast. The effects were less obvious in the northern United States, including New England and the Great Lakes states. The greatest pollen increases came from trees, as opposed to grasses and weeds.

Allergies do not just trigger sniffles and sneezes; they have serious effects on public health in the form of asthma and other respiratory conditions. Studies have shown that students do less well in school during peak pollen season. Of special concern at the moment is that high-pollen periods have been associated with greater susceptibility to respiratory viruses. The U.S. has nearly 25 million people with asthma and 19 million adults reported hay fever in the past 12 months. Research suggests that the early onset of pollen season correlates with a higher risk of hospitalization for asthma.

There are far fewer pollen monitoring stations than those measuring particle pollutants and air quality. As the climate warms, we need to pay more attention to pollen as an airborne pollutant.

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