“The earth is always changing…..readjusting to our existence. Each era is full of unique challenges.”
- Val Uchendu
The Earth has pushed human minds for long to observe and think critically. We learn crucial facts about science and ourselves just by mere inspection of the world. It’s also safe to say that nature has a potent way of enlightening us and curing us.
The Earth is truly an incredible and mysterious place and we’re only now beginning to understand the vast number of secrets it has. It is in a state of flux, constantly changing and evolving with time. Humans have only just begun to scratch the surface of the earth’s complexities and there are many mysteries that remain unsolved & are yet to be unraveled.
One of such mysteries is of the Ozone Hole.
But before discussing the hole in the ozone layer, let's talk what the ozone is first. Mostly found in the stratosphere, it's a diaphanous layer of the atmosphere more than 20 miles (10-50 km) above sea level made of the ozone gas. It forms an invisible protective shield over the planet, absorbing energetic and damaging ultraviolet radiation from the sun.
It absorbs some ultraviolet radiations and reflects the rest back, acting as the Earth's sunscreen of sorts, putting an invisible shield of protection over the planet protecting it from harmful ultraviolet radiations coming from the sun. Without it, we would be bathed in dangerous radiation on an everyday basis, with side effects ranging from cataracts to cancer. Without it, complex life on Earth wouldn't dare to exist.
Over the years, scientists have learned that the layer is extremely thin, that it varies over the course of days and seasons and that it has different concentrations over different areas. Even as researchers began to study ozone levels over time, they started to think about whether it was capable of being depleted……and not long after, they got the answer to that question.
Schematic of the Antarctic ozone hole's growth
Source:- https://uk-air.defra.gov.uk/research/ozone-uv/moreinfo?view=antarctica-hole-explained
The first hints that human activity threatened the ozone layer emerged in the 1970s about how agricultural fertilizers or supersonic aircrafts might reduce ozone levels.
But it was actually in the 1980s that a team of scientists shocked the world when they detected a hole in the ozone layer over Antarctica and forever altered how people view the environment. It was the void that changed public perception of the environment forever—a growing spot so scary, it mobilized a generation of scientists and brought the world together to battle a threat to our atmosphere.
The image of the ozone hole over Antarctica – a widening rip in the very fabric of the Earth’s sun-shielding layer – a symbol of destruction so present and obvious, even politicians couldn’t ignore it.
Turned out the real danger was contained in things like bottles of hairspray and cans of shaving cream. In 1974, a landmark paper showed that the major culprit to blame for this situation were CFC's or chlorofluorocarbons. They were gases used in a variety of products from refrigerators to aerosols to home insulation foams.
This discovery earned Paul Crutzen, Mario Molina and F. Sherwood Rowland a Nobel Prize and gave light to a major crisis for humanity to tackle.
All eyes were now turned to the invisible layer surrounding Earth. The discovery stoked public fears to a very high extent with statements like "It’s like AIDS from the sky" about ultraviolet radiations not being uncommon to hear on the news media.
So, how exactly was this fixed? Through the beginning of a decades-long process of intense mobilization, heavy investment, marshalling of economic resources and coordinating international political action to fix this looming existential threat over humanity.
The Montreal Protocol was established in 1987 to preserve the ozone layer by gradually banning the responsible substances aka CFC's. The treaty recognized "common but differentiated responsibilities," staggered phase-out timelines for developed and developing nations and established a multilateral fund to give developing countries financial and technical assistance to enable them meet their obligations. All of these provisions were made to facilitate compliance.
CFC manufacture and usage came to an end in the 1990s and the first part of the 2000s. 98% of the compounds covered by the pact had been phased out as of 2009. Six revisions have resulted in ever-tighter limitations on compounds introduced to replace CFCs, such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), which the treaty permits when scientific data reveals that additional action is required. These alternatives ended up being detrimental to the climate, despite being beneficial for the ozone layer. For instance, the most widely used HCFC has a nearly 2,000-fold greater potential for global warming than carbon dioxide.
The treaty's advantages for the environment have been a welcome byproduct. In 2010, the Montreal Protocol reduced emissions by between 9.7 and 12.5 gigatons of CO2 equivalent, which is roughly five to six times greater than the Kyoto Protocol's target. The Kyoto Protocol was an international agreement signed in 1997 with the goal of reducing greenhouse gas emissions. The Kigali Amendment, which would restrict the use of HFCs, was adopted in 2016, and it will save up to 0.5 C of global warming by 2100.
Since it's adoption, the Montreal Protocol has been signed by every country on Earth – to date the only treaty to be universally ratified. It's widely considered a triumph of international environmental cooperation.
According to some models, the Montreal Protocol and its amendments have helped prevent up to two million cases of skin cancer yearly and avoided millions of cataract cases worldwide.
Source:- https://www.unep.org/ozonaction/who-we-are/about-montreal-protocol
Had the world not banned CFCs, we would now find ourselves nearing massive ozone depletion.
By 2050, it's pretty well-established we would have had ozone hole-like conditions over the whole planet and the planet would have become uninhabitable. Instead, we've been able to get to a point where the ozone layer is expected to return to pre-1980 levels by 2050.
30 years after its discovery, the ozone hole just doesn’t have the horror-story connotations it once did. The conversation around it entirely changed — and not on it's own but because of the consistent efforts of environmentalists and the public combined with actions taken by politicians after listening to the people.
This is important to remember because a lot of times, we can end up feeling defeated and exhausted. We can feel as if our words have no effect and our efforts don't matter. Nothing we do, as individuals or in small groups, doesn't end up changing how things happen in the long run.
But this incident clearly proves otherwise, as long as there is a clear goal in mind and we strive for it with full determination and focus, we can change the course of history and achieve our aspirations.
The planet is nothing but truthful when it comes to outcomes. It is a mirror that reflects back our deeds and holds humanity accountable for it's actions. With the gain of better knowledge with time, let's make good decisions when it comes to the planet's and our own individual health.
It’s not every day we get to talk about a scientific horror story that has a happy ending, let's ensure we have more.
Article by:- Disha Tiwari
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