With climate change, plastic pollution and the threat of a sixth mass extinction, humanity has made more mess.
But when humans, political factions and nations decided to stand together, they were also able to clean up some of the worst environmental problems caused by humanity, such as fixing the hole in the ozone layer, improving the air quality and save several species from imminent extinction.
“We can be good at cleaning up our mess, it all depends on whether we choose to do it or not and what we prioritize,” said Professor Sheril Kirshenbaum of Michigan State University.
On Earth Day, The Associated Press asked more than 25 experts what they think about the environmental problems humanity has been trying to fix.
“There have been extraordinary successes,” said Rob Jackson of Stanford University. It’s easy to get tunnel vision with everything that’s going wrong and there are many things that need to change quickly. But it’s great to celebrate the successes of the past, here in the United States, but also elsewhere in the world. »
Here are the four successes that are mentioned most often.
Heal the ozone layer
Repairing the hole in the ozone layer was, by far, the first choice of the specialists interviewed.
“At that moment, countries that usually compete with each other realized they were facing a common threat and they decided to find a solution,” Carol Browner, the former head of the United States Environmental Protection Agency (EPA).
Scientists had discovered in the 1970s that certain chemicals used in particular for refrigeration destroyed the ozone layer which protected the Earth from the ultraviolet rays associated with skin cancer.
The ozone layer was thinning everywhere, opening a hole over Antarctica. This not only increased the risk of skin cancer, but also that of cataracts and profound changes to ecosystems all over the planet, recalled Jason West, a climatologist at the University of North Carolina.
“This is the first time we’ve fixed a problem that we were responsible for and that threatened the survival of the planet,” said Jackson of Stanford.
In 1987, countries around the world signed the Montreal Protocol, the first treaty of its kind that banned chemicals that were eating away at the atmosphere. Today, all nations have signed up to the treaty and 99% of these harmful chemicals are no longer used, “saving two million people from skin cancer each year,” Inger Andersen, who leads the program, said in an email. United Nations Environment Agency (UNEP).
The hole in the ozone layer above Antarctica has continued to grow for about twenty years, but has been slowly healing over the past few years. UNEP predicts full healing by the end of the 2030s.
Although the Montreal Protocol is a great success, the fight against climate change is different. The companies that produced the ozone-hazardous chemicals simply started producing their replacements. But for global warming, “it’s more of an existential threat to oil companies,” Jackson said.
Cleaner air and water
In most industrialized countries, the air is much cleaner and healthier than it was 50 or 60 years ago, when large cities were smothered in smog and waterways served as dumping grounds.
It is calculated, for example, that various laws passed in the United States have reduced the prevalence of health problems such as cancer or asthma, saving millions of lives and saving the health care system trillions of dollars.
The number of deaths attributable to air pollution has increased from approximately 95,000 per year in 1990 to 48,000 in 2019.
Solar and wind energy
The rapid decline in the cost of solar and wind energy, which do not produce greenhouse gases, surprises experts and gives them hope that the planet can free itself from the hydrocarbons responsible for global warming.
Between 2010 and 2020, the cost of residential solar power plunged 64% and that of utility-scale solar power generation 82%, according to the National Renewable Energy Lab.
Solar power “is becoming the mainstream energy technology and it’s becoming more affordable,” Jackson said. It is less expensive than virtually any other form of electricity generation. »
Few believed a decade ago that the cost of solar or wind energy would slide so rapidly, several experts have said, attributing the decline to massive investments in the United States, Germany and elsewhere to fight the recession. of 2018.
Threatened species
The bald eagle, peregrine falcon, bustard and humpback whale each represent an environmental success.
All once teetered on the brink of extinction and were protected by law. In some cases, they are now so abundant that some consider them to be harmful or problematic.
“Conservation efforts save some endangered species,” said Stuart Pimm, a Duke University ecologist. We learn how to protect them. »
Experts hail laws and rules adopted around the world to ban the killing and trade of endangered species, and to prevent the destruction of critically needed habitats.
The ban on DDT, a pesticide that had repercussions on the entire food chain, also had a lot to do with it, since the product weakened the shells of the eggs of many birds of prey.