Scientists are building a sensor network to detect the trends in the water chemistry of Lake Huron, one of the five Great Lakes of North America. Researchers hope the data from the Lake Huron project would add to scientific information on the subject.
Key points
- It is the first step towards developing a system that would be capable of measuring the carbon dioxide and pH levels of the Great Lakes over several years.
- Oceans are becoming more acidic as they absorb carbon dioxide that human activity pumps into the atmosphere — the primary cause of climate change.
- Acidification endangers coral reefs and other marine life.
- Studies based on computer models suggest the same thing may be happening in big freshwater systems.
- Recently, it has been observed that by 2100, even the Great Lakes — Superior, Michigan, Huron, Erie, and Ontario — might approach acidity at around the same rate as the oceans.
The Great Lakes
- The Great Lakes, five interconnected bodies of water straddling the US-Canada border that drain into the Gulf of St Lawrence in the North Atlantic through the St Lawrence River, are the largest group of freshwater lakes in the world.
- The US-Canada border passes through Lakes Superior, Huron, Erie, and Ontario; Lake Michigan lies entirely in the US.
- Lakes Michigan and Huron are sometimes considered as a single water body; taken together, they are the world’s largest freshwater lake by surface area. By itself, Lake Huron is the world’s third largest freshwater lake, after Lake Superior and Lake Victoria.
Ocean Acidification and impacts
- Prior to the Industrial Revolution of the 18th to 19th centuries, the ocean’s average pH was about 8.2. Today, the ocean’s average pH is 8.1. This means that the ocean today is about 30 per cent more acidic than in pre-industrial times.
- By 2100, the pH of the ocean could decrease to about 7.8, making the ocean 150 percent more acidic and affecting half of all marine life, according to the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report.
- Ocean acidification is already impacting many ocean species, especially organisms like oysters and corals that make hard shells and skeletons by combining calcium and carbonate from seawater.
- However, as ocean acidification increases, available carbonate ions (CO32-) bond with excess hydrogen, resulting in fewer carbonate ions available for calcifying organisms to build and maintain their shells, skeletons, and other calcium carbonate structures. If the pH gets too low, shells and skeletons can even begin to dissolve.
- Changes in ocean chemistry can affect the behavior of non-calcifying organisms as well. The ability of some fish, like clownfish, to detect predators is decreased in more acidic waters.
- While some species will be harmed by ocean acidification, algae and seagrasses may benefit from higher CO2 conditions in the ocean, as they require CO2 for photosynthesis just like plants on land. There are some ongoing studies examining if growing seaweed can help slow ocean acidification.
(Sources: Indian Express and NOAA)
