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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Petrol in India is cheaper than in countries like Hong Kong, Germany and the UK but costlier than in China, Brazil, Japan, the US, Russia, Pakistan and Sri Lanka, a Bank of Baroda Economics Research report showed.
Rising fuel prices in India have led to considerable debate on which government, state or central, should be lowering their taxes to keep prices under control.
The rise in fuel prices is mainly due to the global price of crude oil (raw material for making petrol and diesel) going up. Further, a stronger dollar has added to the cost of crude oil.
Amongst comparable countries (per capita wise), prices in India are higher than those in Vietnam, Kenya, Ukraine, Bangladesh, Nepal, Pakistan, Sri Lanka, and Venezuela. Countries that are major oil producers have much lower prices.
In the report, the Philippines has a comparable petrol price but has a per capita income higher than India by over 50 per cent.
Countries which have a lower per capita income like Kenya, Bangladesh, Nepal, Pakistan, and Venezuela have much lower prices of petrol and hence are impacted less than India.
“Therefore there is still a strong case for the government to consider lowering the taxes on fuel to protect the interest of the people,” the report argued.
India is the world’s third-biggest oil consuming and importing nation. It imports 85 per cent of its oil needs and so prices retail fuel at import parity rates.
With the global surge in energy prices, the cost of producing petrol, diesel and other petroleum products also went up for oil companies in India.
They raised petrol and diesel prices by Rs 10 a litre in just over a fortnight beginning March 22 but hit a pause button soon after as the move faced criticism and the opposition parties asked the government to cut taxes instead.
India imports most of its oil from a group of countries called the ‘OPEC +’ (i.e, Iran, Iraq, Saudi Arabia, Venezuela, Kuwait, United Arab Emirates, Russia, etc), which produces 40% of the world’s crude oil.
As they have the power to dictate fuel supply and prices, their decision of limiting the global supply reduces supply in India, thus raising prices
The government charges about 167% tax (excise) on petrol and 129% on diesel as compared to US (20%), UK (62%), Italy and Germany (65%).
The abominable excise duty is 2/3rd of the cost, and the base price, dealer commission and freight form the rest.
Here is an approximate break-up (in Rs):
a)Base Price | 39 |
b)Freight | 0.34 |
c) Price Charged to Dealers = (a+b) | 39.34 |
d) Excise Duty | 40.17 |
e) Dealer Commission | 4.68 |
f) VAT | 25.35 |
g) Retail Selling Price | 109.54 |
Looked closely, much of the cost of petrol and diesel is due to higher tax rate by govt, specifically excise duty.
So the question is why government is not reducing the prices ?
India, being a developing country, it does require gigantic amount of funding for its infrastructure projects as well as welfare schemes.
However, we as a society is yet to be tax-compliant. Many people evade the direct tax and that’s the reason why govt’s hands are tied. Govt. needs the money to fund various programs and at the same time it is not generating enough revenue from direct taxes.
That’s the reason why, govt is bumping up its revenue through higher indirect taxes such as GST or excise duty as in the case of petrol and diesel.
Direct taxes are progressive as it taxes according to an individuals’ income however indirect tax such as excise duty or GST are regressive in the sense that the poorest of the poor and richest of the rich have to pay the same amount.
Does not matter, if you are an auto-driver or owner of a Mercedes, end of the day both pay the same price for petrol/diesel-that’s why it is regressive in nature.
But unlike direct tax where tax evasion is rampant, indirect tax can not be evaded due to their very nature and as long as huge no of Indians keep evading direct taxes, indirect tax such as excise duty will be difficult for the govt to reduce, because it may reduce the revenue and hamper may programs of the govt.
Globally, around 80% of wastewater flows back into the ecosystem without being treated or reused, according to the United Nations.
This can pose a significant environmental and health threat.
In the absence of cost-effective, sustainable, disruptive water management solutions, about 70% of sewage is discharged untreated into India’s water bodies.
A staggering 21% of diseases are caused by contaminated water in India, according to the World Bank, and one in five children die before their fifth birthday because of poor sanitation and hygiene conditions, according to Startup India.
As we confront these public health challenges emerging out of environmental concerns, expanding the scope of public health/environmental engineering science becomes pivotal.
For India to achieve its sustainable development goals of clean water and sanitation and to address the growing demands for water consumption and preservation of both surface water bodies and groundwater resources, it is essential to find and implement innovative ways of treating wastewater.
It is in this context why the specialised cadre of public health engineers, also known as sanitation engineers or environmental engineers, is best suited to provide the growing urban and rural water supply and to manage solid waste and wastewater.
Traditionally, engineering and public health have been understood as different fields.
Currently in India, civil engineering incorporates a course or two on environmental engineering for students to learn about wastewater management as a part of their pre-service and in-service training.
Most often, civil engineers do not have adequate skills to address public health problems. And public health professionals do not have adequate engineering skills.
India aims to supply 55 litres of water per person per day by 2024 under its Jal Jeevan Mission to install functional household tap connections.
The goal of reaching every rural household with functional tap water can be achieved in a sustainable and resilient manner only if the cadre of public health engineers is expanded and strengthened.
In India, public health engineering is executed by the Public Works Department or by health officials.
This differs from international trends. To manage a wastewater treatment plant in Europe, for example, a candidate must specialise in wastewater engineering.
Furthermore, public health engineering should be developed as an interdisciplinary field. Engineers can significantly contribute to public health in defining what is possible, identifying limitations, and shaping workable solutions with a problem-solving approach.
Similarly, public health professionals can contribute to engineering through well-researched understanding of health issues, measured risks and how course correction can be initiated.
Once both meet, a public health engineer can identify a health risk, work on developing concrete solutions such as new health and safety practices or specialised equipment, in order to correct the safety concern..
There is no doubt that the majority of diseases are water-related, transmitted through consumption of contaminated water, vectors breeding in stagnated water, or lack of adequate quantity of good quality water for proper personal hygiene.
Diseases cannot be contained unless we provide good quality and adequate quantity of water. Most of the world’s diseases can be prevented by considering this.
Training our young minds towards creating sustainable water management systems would be the first step.
Currently, institutions like the Indian Institute of Technology, Madras (IIT-M) are considering initiating public health engineering as a separate discipline.
To leverage this opportunity even further, India needs to scale up in the same direction.
Consider this hypothetical situation: Rajalakshmi, from a remote Karnataka village spots a business opportunity.
She knows that flowers, discarded in the thousands by temples can be handcrafted into incense sticks.
She wants to find a market for the product and hopefully, employ some people to help her. Soon enough though, she discovers that starting a business is a herculean task for a person like her.
There is a laborious process of rules and regulations to go through, bribes to pay on the way and no actual means to transport her product to its market.
After making her first batch of agarbathis and taking it to Bengaluru by bus, she decides the venture is not easy and gives up.
On the flipside of this is a young entrepreneur in Bengaluru. Let’s call him Deepak. He wants to start an internet-based business selling sustainably made agarbathis.
He has no trouble getting investors and to mobilise supply chains. His paperwork is over in a matter of days and his business is set up quickly and ready to grow.
Never mind that the business is built on aggregation of small sellers who will not see half the profit .
Is this scenario really all that hypothetical or emblematic of how we think about entrepreneurship in India?
Between our national obsession with unicorns on one side and glorifying the person running a pakora stall for survival as an example of viable entrepreneurship on the other, is the middle ground in entrepreneurship—a space that should have seen millions of thriving small and medium businesses, but remains so sparsely occupied that you could almost miss it.
If we are to achieve meaningful economic growth in our country, we need to incorporate, in our national conversation on entrepreneurship, ways of addressing the missing middle.
Spread out across India’s small towns and cities, this is a class of entrepreneurs that have been hit by a triple wave over the last five years, buffeted first by the inadvertent fallout of demonetization, being unprepared for GST, and then by the endless pain of the covid-19 pandemic.
As we finally appear to be reaching some level of normality, now is the opportune time to identify the kind of industries that make up this layer, the opportunities they should be afforded, and the best ways to scale up their functioning in the shortest time frame.
But, why pay so much attention to these industries when we should be celebrating, as we do, our booming startup space?
It is indeed true that India has the third largest number of unicorns in the world now, adding 42 in 2021 alone. Braving all the disruptions of the pandemic, it was a year in which Indian startups raised $24.1 billion in equity investments, according to a NASSCOM-Zinnov report last year.
However, this is a story of lopsided growth.
The cities of Bengaluru, Delhi/NCR, and Mumbai together claim three-fourths of these startup deals while emerging hubs like Ahmedabad, Coimbatore, and Jaipur account for the rest.
This leap in the startup space has created 6.6 lakh direct jobs and a few million indirect jobs. Is that good enough for a country that sends 12 million fresh graduates to its workforce every year?
It doesn’t even make a dent on arguably our biggest unemployment in recent history—in April 2020 when the country shutdown to battle covid-19.
Technology-intensive start-ups are constrained in their ability to create jobs—and hybrid work models and artificial intelligence (AI) have further accelerated unemployment.
What we need to focus on, therefore, is the labour-intensive micro, small and medium enterprise (MSME). Here, we begin to get to a definitional notion of what we called the mundane middle and the problems it currently faces.
India has an estimated 63 million enterprises. But, out of 100 companies, 95 are micro enterprises—employing less than five people, four are small to medium and barely one is large.
The questions to ask are: why are Indian MSMEs failing to grow from micro to small and medium and then be spurred on to make the leap into large companies?
At the Global Alliance for Mass Entrepreneurship (GAME), we have advocated for a National Mission for Mass Entrepreneurship, the need for which is more pronounced now than ever before.
Whenever India has worked to achieve a significant economic milestone in a limited span of time, it has worked best in mission mode. Think of the Green Revolution or Operation Flood.
From across various states, there are enough examples of approaches that work to catalyse mass entrepreneurship.
The introduction of entrepreneurship mindset curriculum (EMC) in schools through alliance mode of working by a number of agencies has shown significant improvement in academic and life outcomes.
Through creative teaching methods, students are encouraged to inculcate 21st century skills like creativity, problem solving, critical thinking and leadership which are not only foundational for entrepreneurship but essential to thrive in our complex world.
Udhyam Learning Foundation has been involved with the Government of Delhi since 2018 to help young people across over 1,000 schools to develop an entrepreneurial mindset.
One pilot programme introduced the concept of ‘seed money’ and saw 41 students turn their ideas into profit-making ventures. Other programmes teach qualities like grit and resourcefulness.
If you think these are isolated examples, consider some larger data trends.
The Observer Research Foundation and The World Economic Forum released the Young India and Work: A Survey of Youth Aspirations in 2018.
When asked which type of work arrangement they prefer, 49% of the youth surveyed said they prefer a job in the public sector.
However, 38% selected self-employment as an entrepreneur as their ideal type of job. The spirit of entrepreneurship is latent and waiting to be unleashed.
The same can be said for building networks of successful women entrepreneurs—so crucial when the participation of women in the Indian economy has declined to an abysmal 20%.
The majority of India’s 63 million firms are informal —fewer than 20% are registered for GST.
Research shows that companies that start out as formal enterprises become two-three times more productive than a similar informal business.
So why do firms prefer to be informal? In most cases, it’s because of the sheer cost and difficulty of complying with the different regulations.
We have academia and non-profits working as ecosystem enablers providing insights and evidence-based models for growth. We have large private corporations and philanthropic and funding agencies ready to invest.
It should be in the scope of a National Mass Entrepreneurship Mission to bring all of them together to work in mission mode so that the gap between thought leadership and action can finally be bridged.