The ozone layer is a belt of naturally occurring ozone gas in the stratosphere. It absorbs the harmful ultraviolet radiations emitted from the sun before it reaches the Earth’s atmosphere. Ozone depleting substances (ODS) like CFCs and other organic substances that are used in appliances are responsible for the depletion and thinning of ozone layer.
The Montreal Protocol is an international treaty signed to protect the ozone layer where the parties agreed to phase out production of ODSs. It has proved to be one of the most successful international treaties as the ozone layer is slowly reviving and the ozone hole over Antarctica is also healing.
The occurrence of ozone
Ozone is present in a very small amount in the Earth’s atmosphere, averaging about three molecules of ozone for every ten million molecules of air. It is measured in Dobson Unit (Db) which is equivalent to a 0.01 mm thickness of pure ozone if brought down to ground level pressure (1 atm) and temperature (0°C). The global average of ozone thickness is about 300Db.
Most of the ozone, around 90 per cent, resides in the upper layer of atmosphere called the stratosphere, which is 10 km above the Earth’s surface. It forms a blanket like structure around the Earth’s atmosphere called the ‘ozone layer’. The remaining 10 per cent is present in the lower region of the atmosphere, commonly known as the troposphere. The ozone layer filters out the harmful ultraviolet (UV) radiations from the sun before reaching the Earth by absorbing them. Thus, it is also known as the ‘Earth’s natural sunscreen’.
The role of ozone in the two regions of the atmosphere is different. The stratospheric ozone is called as the ‘good ozone’ due to its role in shielding the biologically damaging ultraviolet sunlight (called UV-B). Whereas, tropospheric ozone is known as ‘bad ozone’ because of its highly reactive nature with other gas molecules and it is toxic for living systems. Surface ozone is also a key component in formation of photochemical smog which is a potential air pollutant. Therefore, ozone basically has two environmental issues – the increasing concentration of ozone in the troposphere and the depletion of ozone layer in the stratosphere due to the release of several ozone-depleting substances (ODS).
Depletion of Ozone layer
The ozone molecules in the stratosphere are constantly formed and destroyed during any given time. Thus, the concentration of ozone is supposed to remain relatively stable unless the chemistry is drastically disturbed by external factors. In the beginning of the 1970s, the scientific community discovered that the ozone layer has been depleting more quickly than it is naturally formed. It was due to the human produced ozone-depleting organic compounds generally identified as halocarbons. They are combinations of elements like chlorine, bromine, fluorine, oxygen and hydrogen. Collectively they are known as Chlorofluorocarbons (CFCs) and Hydroclorofluorocarbons (HCFCs). Other ozone depleting substances are carbon tetrachloride, methyl chloroform and methyl bromide. These substances are non-reactive, non-flammable and non-toxic and can travel for a long distance reaching up to the stratosphere in a few years.
In the presence of UV light they produce free chlorine, fluorine and bromine which when in contact with ozone break down their molecules. It is estimated that, one chlorine molecule can destroy 100,000 ozone molecules before it is removed from the stratosphere (Environmental Protection Agency, US, 2016). ODSs are used in our day today appliances like refrigerators, air conditioners, fire extinguishers, foam insulators etc. The use of these substances is banned legally in most of the countries but illegal use is still widespread.
Finding a replacement for CFCs became inevitable and with effort the global scientific community found substances which are less harmful than CFCs. Hydrochlorofluorocarbons (HCFCs) are one of the temporary replacements for CFCs, while Hydroflourocarbons (HFCs) are the main long term replacements for CFCs and HCFCs. Since chlorine has the highest potential to destroy ozone, products that are entirely free of chlorine will be the ultimate replacements for CFCs and HCFCs.
The growing awareness of the serious impacts of ODSs in the ozone layer led to the groundbreaking Montreal Protocol on Substances that Deplete the Ozone Layer which was signed in 1987. It was the first joint international effort to protect the stratospheric ozone. The parties under the Protocol decided to phase out CFCs and halon productions. The measures taken up under this agreement was met with positive results as ODSs are falling and the ozone layer is expected to be fully healed near the middle of the 21st century (USEPA, 2017).
Fig: Surface and stratospheric ozone
Biological impacts of ozone depletion
Most of the biological impacts of ozone layer depletion are due to the damaging nature of UV-B radiations. The reduction of ozone concentration in the stratosphere allows more UV-B radiations to penetrate into the Earth’s atmosphere. Research says that 1 per cent decrease in ozone overhead can result in a 2 per cent increase in UV-B intensity at ground level (Baird and Cann, 2008). The DNA molecules of a living body absorb the UV radiation and can cause several genetic aberrations. It can be linked to several human conditions like skin cancers, cataracts, macular degeneration (gradual death of retinal cells) etc. Malignant melanoma is a widespread skin cancer caused by over-exposure to UV-B radiations. The impacts of UV-B radiation is confined not only to humans but plants as well. The efficiency of plant photosynthesis is reduced leading to less leaves, fruits and seeds. It also affects the production of microscopic phytoplankton which is an important base in the marine food chain.
The tropospheric ozone also has multiple effects on food production, forest growth and human health. It aggravates various respiratory diseases like asthma and emphysema, and is also linked to permanent lung damage. In plants, ozone induces early senescence and abscission of leaves, it also reduces the rate of photosynthetic carbon fixation and thereby a decrease in fruit and seed production (Wilkinson et al., 2012).
Healing of ozone hole in Antarctica
The ozone hole in Antarctica is not an actual hole but an area of exceptionally thin layer of ozone at the stratosphere that happens during the Southern Hemisphere Spring (August-October). This is due to the formation of Polar Stratospheric Clouds (PSC) particles during the winter. The inactive form of chlorine is converted into active form (Chlorine gas) in the presence of water and ice. Thus when spring comes, sunlight breaks the bond between two chlorine atoms which are in active form and undergoes a series of catalytic ozone destructions. The ozone hole grows throughout spring until the cold polar vortex vanishes and stabilizes the ozone layer. This cycle repeats each year during the spring.
On the bright side, research and monitoring have shown that the ozone hole over Antarctica has started to heal. It was reported in 2015 that the hole was around 14 million sq km smaller than it was in the year 2000, an area roughly the size of India (Solomon et al. 2016). This milestone has been credited to the international joint efforts in phasing out of ozone depleting substances. Meanwhile, researchers say that even though production of ODSs has been phased out in many countries, there is still plenty of chlorine left in the atmosphere. It is expected that complete recovery of ozone depletion would happen by around 2050-60 owing to the long lifetime and slow decay of chlorine.
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The United Nations has shaped so much of global co-operation and regulation that we wouldn’t recognise our world today without the UN’s pervasive role in it. So many small details of our lives – such as postage and copyright laws – are subject to international co-operation nurtured by the UN.
In its 75th year, however, the UN is in a difficult moment as the world faces climate crisis, a global pandemic, great power competition, trade wars, economic depression and a wider breakdown in international co-operation.
Still, the UN has faced tough times before – over many decades during the Cold War, the Security Council was crippled by deep tensions between the US and the Soviet Union. The UN is not as sidelined or divided today as it was then. However, as the relationship between China and the US sours, the achievements of global co-operation are being eroded.
The way in which people speak about the UN often implies a level of coherence and bureaucratic independence that the UN rarely possesses. A failure of the UN is normally better understood as a failure of international co-operation.
We see this recently in the UN’s inability to deal with crises from the ethnic cleansing of the Rohingya Muslims in Myanmar, to civil conflict in Syria, and the failure of the Security Council to adopt a COVID-19 resolution calling for ceasefires in conflict zones and a co-operative international response to the pandemic.
The UN administration is not primarily to blame for these failures; rather, the problem is the great powers – in the case of COVID-19, China and the US – refusing to co-operate.
Where states fail to agree, the UN is powerless to act.
Marking the 75th anniversary of the official formation of the UN, when 50 founding nations signed the UN Charter on June 26, 1945, we look at some of its key triumphs and resounding failures.
Five successes
1. Peacekeeping
The United Nations was created with the goal of being a collective security organisation. The UN Charter establishes that the use of force is only lawful either in self-defence or if authorised by the UN Security Council. The Security Council’s five permanent members, being China, US, UK, Russia and France, can veto any such resolution.
The UN’s consistent role in seeking to manage conflict is one of its greatest successes.
A key component of this role is peacekeeping. The UN under its second secretary-general, the Swedish statesman Dag Hammarskjöld – who was posthumously awarded the Nobel Peace prize after he died in a suspicious plane crash – created the concept of peacekeeping. Hammarskjöld was responding to the 1956 Suez Crisis, in which the US opposed the invasion of Egypt by its allies Israel, France and the UK.
UN peacekeeping missions involve the use of impartial and armed UN forces, drawn from member states, to stabilise fragile situations. “The essence of peacekeeping is the use of soldiers as a catalyst for peace rather than as the instruments of war,” said then UN Secretary-General Javier Pérez de Cuéllar, when the forces won the 1988 Nobel Peace Prize following missions in conflict zones in the Middle East, Africa, Asia, Central America and Europe.
However, peacekeeping also counts among the UN’s major failures.
2. Law of the Sea
Negotiated between 1973 and 1982, the UN Convention on the Law of the Sea (UNCLOS) set up the current international law of the seas. It defines states’ rights and creates concepts such as exclusive economic zones, as well as procedures for the settling of disputes, new arrangements for governing deep sea bed mining, and importantly, new provisions for the protection of marine resources and ocean conservation.
Mostly, countries have abided by the convention. There are various disputes that China has over the East and South China Seas which present a conflict between power and law, in that although UNCLOS creates mechanisms for resolving disputes, a powerful state isn’t necessarily going to submit to those mechanisms.
Secondly, on the conservation front, although UNCLOS is a huge step forward, it has failed to adequately protect oceans that are outside any state’s control. Ocean ecosystems have been dramatically transformed through overfishing. This is an ecological catastrophe that UNCLOS has slowed, but failed to address comprehensively.
3. Decolonisation
The idea of racial equality and of a people’s right to self-determination was discussed in the wake of World War I and rejected. After World War II, however, those principles were endorsed within the UN system, and the Trusteeship Council, which monitored the process of decolonisation, was one of the initial bodies of the UN.
Although many national independence movements only won liberation through bloody conflicts, the UN has overseen a process of decolonisation that has transformed international politics. In 1945, around one third of the world’s population lived under colonial rule. Today, there are less than 2 million people living in colonies.
When it comes to the world’s First Nations, however, the UN generally has done little to address their concerns, aside from the non-binding UN Declaration on the Rights of Indigenous Peoples of 2007.
4. Human rights
The Human Rights Declaration of 1948 for the first time set out fundamental human rights to be universally protected, recognising that the “inherent dignity and of the equal and inalienable rights of all members of the human family is the foundation of freedom, justice and peace in the world”.
Since 1948, 10 human rights treaties have been adopted – including conventions on the rights of children and migrant workers, and against torture and discrimination based on gender and race – each monitored by its own committee of independent experts.
The language of human rights has created a new framework for thinking about the relationship between the individual, the state and the international system. Although some people would prefer that political movements focus on ‘liberation’ rather than ‘rights’, the idea of human rights has made the individual person a focus of national and international attention.
5. Free trade
Depending on your politics, you might view the World Trade Organisation as a huge success, or a huge failure.
The WTO creates a near-binding system of international trade law with a clear and efficient dispute resolution process.
The majority Australian consensus is that the WTO is a success because it has been good for Australian famers especially, through its winding back of subsidies and tariffs.
However, the WTO enabled an era of globalisation which is now politically controversial.
Recently, the US has sought to disrupt the system. In addition to the trade war with China, the Trump Administration has also refused to appoint tribunal members to the WTO’s Appellate Body, so it has crippled the dispute resolution process. Of course, the Trump Administration is not the first to take issue with China’s trade strategies, which include subsidises for ‘State Owned Enterprises’ and demands that foreign firms transfer intellectual property in exchange for market access.
The existence of the UN has created a forum where nations can discuss new problems, and climate change is one of them. The Intergovernmental Panel on Climate Change (IPCC) was set up in 1988 to assess climate science and provide policymakers with assessments and options. In 1992, the UN Framework Convention on Climate Change created a permanent forum for negotiations.
However, despite an international scientific body in the IPCC, and 165 signatory nations to the climate treaty, global greenhouse gas emissions have continued to increase.
Under the Paris Agreement, even if every country meets its greenhouse gas emission targets we are still on track for ‘dangerous warming’. Yet, no major country is even on track to meet its targets; while emissions will probably decline this year as a result of COVID-19, atmospheric concentrations of greenhouse gases will still increase.
This illustrates a core conundrum of the UN in that it opens the possibility of global cooperation, but is unable to constrain states from pursuing their narrowly conceived self-interests. Deep co-operation remains challenging.
Five failures of the UN
1. Peacekeeping
During the Bosnian War, Dutch peacekeeping forces stationed in the town of Srebrenica, declared a ‘safe area’ by the UN in 1993, failed in 1995 to stop the massacre of more than 8000 Muslim men and boys by Bosnian Serb forces. This is one of the most widely discussed examples of the failures of international peacekeeping operations.
On the massacre’s 10th anniversary, then UN Secretary General Kofi Annan wrote that the UN had “made serious errors of judgement, rooted in a philosophy of impartiality”, contributing to a mass murder that would “haunt our history forever”.
If you look at some of the other infamous failures of peacekeeping missions – in places such as Rwanda, Somalia and Angola – it is the limited powers given to peacekeeping operations that have resulted in those failures.
2. The invasion of Iraq
The invasion of Iraq by the US in 2003, which was unlawful and without Security Council authorisation, reflects the fact that the UN is has very limited capacity to constrain the actions of great powers.
The Security Council designers created the veto power so that any of the five permanent members could reject a Council resolution, so in that way it is programmed to fail when a great power really wants to do something that the international community generally condemns.
In the case of the Iraq invasion, the US didn’t veto a resolution, but rather sought authorisation that it did not get. The UN, if you go by the idea of collective security, should have responded by defending Iraq against this unlawful use of force.
The invasion proved a humanitarian disaster with the loss of more than 400,000 lives, and many believe that it led to the emergence of the terrorist Islamic State.
3. Refugee crises
The UN brokered the 1951 Refugee Convention to address the plight of people displaced in Europe due to World War II; years later, the 1967 Protocol removed time and geographical restrictions so that the Convention can now apply universally (although many countries in Asia have refused to sign it, owing in part to its Eurocentric origins).
Despite these treaties, and the work of the UN High Commission for Refugees, there is somewhere between 30 and 40 million refugees, many of them, such as many Palestinians, living for decades outside their homelands. This is in addition to more than 40 million people displaced within their own countries.
While for a long time refugee numbers were reducing, in recent years, particularly driven by the Syrian conflict, there have been increases in the number of people being displaced.
During the COVID-19 crisis, boatloads of Rohingya refugees were turned away by port after port. This tragedy has echoes of pre-World War II when ships of Jewish refugees fleeing Nazi Germany were refused entry by multiple countries.
And as a catastrophe of a different kind looms, there is no international framework in place for responding to people who will be displaced by rising seas and other effects of climate change.
4. Conflicts without end
Across the world, there is a shopping list of unresolved civil conflicts and disputed territories.
Palestine and Kashmir are two of the longest-running failures of the UN to resolve disputed lands. More recent, ongoing conflicts include the civil wars in Syria and Yemen.
The common denominator of unresolved conflicts is either division among the great powers, or a lack of international interest due to the geopolitical stakes not being sufficiently high. For instance, the inaction during the Rwandan civil war in the 1990s was not due to a division among great powers, but rather a lack of political will to engage.
In Syria, by contrast, Russia and the US have opposing interests and back opposing sides: Russia backs the government of the Syrian dictator Bashar al-Assad, whereas the US does not.
5. Acting like it’s 1945
The UN is increasingly out of step with the reality of geopolitics today.
The permanent members of the Security Council reflect the division of power internationally at the end of World War II. The continuing exclusion of Germany, Japan, and rising powers such as India and Indonesia, reflects the failure to reflect the changing balance of power.
Also, bodies such as the IMF and the World Bank, which are part of the UN system, continue to be dominated by the West. In response, China has created potential rival institutions such as the Asian Infrastructure Investment Bank.
Western domination of UN institutions undermines their credibility. However, a more fundamental problem is that institutions designed in 1945 are a poor fit with the systemic global challenges – of which climate change is foremost – that we face today.