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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- Lowering Emissions by Accelerating Forest Finance (LEAF) Coalition, a collective of the United States, United Kingdom and Norway governments, came up with a $1 billion fund.
- LEAF is supported by transnational corporations (TNCs) like Unilever plc, Amazon.com, Inc, Nestle, Airbnb, Inc as well as Emergent, a US-based non-profit.
- The world lost more than 10 million hectares of primary tropical forest cover last year, an area roughly the size of Switzerland.
- Ending tropical and subtropical forest loss by 2030 is a crucial part of meeting global climate, biodiversity and sustainable development goals. Protecting tropical forests offers one of the biggest opportunities for climate action in the coming decade.
- Tropical forests are massive carbon sinks and by investing in their protection, public and private players are likely to stock up on their carbon credits.
- The LEAF coalition initiative is a step towards concretising the aims and objectives of the Reducing Emissions from Deforestation and Forest Degradation (REDD+) mechanism.
- REDD+ was created by the United Nations Framework Convention on Climate Change (UNFCCC). It monetised the value of carbon locked up in the tropical forests of most developing countries, thereby propelling these countries to help mitigate climate change.
- It is a unique initiative as it seeks to help developing countries in battling the double-edged sword of development versus ecological commitment.
- The initiative comes at a crucial time. The tropics have lost close to 12.2 million hectares (mha) of tree cover last year according to global estimates released by Global Forest Watch.
- Of this, a loss of 4.2 mha occurred within humid tropical primary forests alone. It should come as no surprise that most of these lost forests were located in the developing countries of Latin America, Africa and South Asia.
- Brazil has fared dismally on the parameter of ‘annual primary forest loss’ among all countries. It has lost 1.7 mha of primary forests that are rich storehouse of carbon. India’s estimated loss in 2020 stands at 20.8 kilo hectares.
- Between 2002-2020, Brazil’s total area of humid primary forest reduced by 7.7 per cent while India’s reduced by 3.4 per cent.
- Although the loss in India is not as drastic as in Brazil, its position is nevertheless precarious. For India, this loss is equivalent to 951 metric tonnes worth carbon dioxide emissions released in the atmosphere.
- It is important to draw comparisons between Brazil and India as both countries have adopted a rather lackadaisical attitude towards deforestation-induced climate change. The Brazilian government hardly did anything to control the massive fires that gutted the Amazon rainforest in 2019.
- It is mostly around May that forest fires peak in India. However, this year India, witnessed massive forest fires in early March in states like Odisha, Uttarakhand, Madhya Pradesh and Mizoram among others.
- The European Union’s Copernicus Atmospheric Monitoring Service claimed that 0.2 metric tonnes of carbon was emitted in the Uttarakhand forest fires.
- Implementation of the LEAF Coalition plan will help pump in fresh rigour among developing countries like India, that are reluctant to recognise the contributions of their forest dwelling populations in mitigating climate change.
- With the deadline for proposal submission fast approaching, India needs to act swiftly on a revised strategy.
- Although India has pledged to carry out its REDD+ commitments, it is impossible to do so without seeking knowledge from its forest dwelling population.
Context:-
At the recently concluded Leaders’ Summit on Climate in April 2021, Lowering Emissions by Accelerating Forest Finance (LEAF) Coalition, a collective of the United States, United Kingdom and Norway governments, came up with a $1 billion fund plan that shall be offered to countries committed to arrest the decline of their tropical forests by 2030.
[wptelegram-join-channel link=”https://t.me/s/upsctree” text=”Join @upsctree on Telegram”]What is LEAF Coalition?
Why LEAF Coalition?
Brazil & India
According to the UN-REDD programme, after the energy sector, deforestation accounts for massive carbon emissions — close to 11 per cent — in the atmosphere. Rapid urbanisation and commercialisation of forest produce are the main causes behind rampant deforestation across tropical forests.
Tribes, Forests and Government
Disregarding climate change as a valid excuse for the fires, Indian government officials were quick to lay the blame for deforestation on activities of forest dwellers and even labelled them “mischievous elements” and “unwanted elements”.
Policy makers around the world have emphasised the role of indigenous tribes and local communities in checking deforestation. These communities depend on forests for their survival as well as livelihood. Hence, they understand the need to protect forests. However, by posing legitimate environmental concerns as obstacles to real development, governments of developing countries swiftly avoid protection of forests and rights of forest dwellers.
For instance, the Government of India has not been forthcoming in recognising the socio-economic, civil, political or even cultural rights of forest dwellers. According to data from the Union Ministry of Tribal Affairs in December, 2020 over 55 per cent of this population has still not been granted either individual or community ownership of their lands.
To make matters worse, the government has undertaken systematic and sustained measures to render the landmark Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 ineffective in its implementation. The Act had sought to legitimise claims of forest dwellers on occupied forest land.
Various government decisions have seriously undermined the position of indigenous people within India. These include proposing amendments to the obsolete Indian Forest Act, 1927 that give forest officials the power to take away forest dwellers’ rights and to even use firearms with impunity.
There is also the Supreme Court’s order of February, 2019 directing state governments to evict illegal encroachers of forest land or millions of forest dwellers inhabiting forests since generations as a measure to conserve wildlife. Finally, there is the lack of data on novel coronavirus disease (COVID-19) deaths among the forest dwelling population;
Tardy administration, insufficient supervision, apathetic attitude and a lack of political intent defeat the cause of forest dwelling populations in India, thereby directly affecting efforts at arresting deforestation.
Way Forward
Tuntiak Katan, a global indigenous leader from Ecuador and general coordinator of the Global Alliance of Territorial Communities, aptly indicated the next steps at the Climate Summit:
“The first step is recognition of land rights. The second step is the recognition of the contributions of local communities and indigenous communities, meaning the contributions of indigenous peoples.We also need recognition of traditional knowledge practices in order to fight climate change”
Perhaps India can begin by taking the first step.