Take a break from the seemingly never-ending parade of bad news about the environment, and appreciate some welcome good news. It turns out that the acid rain problem has gotten way better and acid in the atmosphere has fallen to pre-industrial levels. Which is not to say that there aren't a bunch of other ways we as humans are still screwing up the natural world, but still — we should definitely celebrate the good things when they happen.
The increased acidity in the atmosphere first became a major concern in the 1970s and '80s, particularly because it leads to acid rain. Industrial emissions of sulfur dioxide and nitrous oxide result in water in the atmosphere mixing with these compounds, lowering the pH balance, and resulting in rain and other precipitation that was much more acidic, which could not only peel paint and corrode steel structures like bridges, but could also damage plants and destroy essential microbe populations in the soil.
These effects were so potentially devastating that governments began trying to take steps to combat the problem. We began introducing new emissions standards for cars and vehicles, for instance, and regulating industries that produced many of the harmful emissions. And it seems those efforts have been pretty effective.
In a new study, researchers analyzed the pH concentration in ice cores taken from Greenland and Antarctica. Ice cores are tubes of ice taken from places where the temperature is always below freezing and ice has been accumulating for thousands of years. By drilling down and removing a long tube of ice, therefore, scientists can analyze the different layers and learn things about the Earth and the atmosphere over the centuries.
Using a sealed system method, researchers area able to determine the pH levels in the ice and extrapolate the probable acidity in the atmosphere throughout history. And it turns out that acid levels in the atmosphere today are pretty close to what researchers now think they were before industrialization.
“Acid pollution in the atmosphere from industry has fallen dramatically since manmade acid pollution took off in the 1930s and peaked in the 1960s and ’70s,” coauthor Helle Astrid Kjær of the Niels Bohr Institute in Denmark said in a statement. “The pollution of acid in the atmosphere is now almost down to the level it was before the pollution really took off.”
So congratulations, everyone! Humankind has officially done a good job of stopping one potentially devastating environmental crisis. Isn't that a nice thing to hear for a change? Now we just have to keep it up.