Dr Parshotam S Manhas
Global warming is the rise in average temperature of atmosphere of the earth due to the increase in greenhouse effect. It is debated as to whether it is a natural occurrence or human activities have accelerated it. It is the process by which absorption and emission of infrared radiation by the gases in the atmosphere are purported to warm a planet’s lower atmosphere and surface. Global warming occurs when carbon dioxide (CO2) and other air pollutants and greenhouse gases collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth’s surface. Normally, this radiation would escape into space-but these pollutants, which can last for years together in the atmosphere, trap the heat and cause the planet to get hotter. That’s what’s known as the greenhouse effect. Naturally occurring greenhouse gases have a mean warming effect of about 33 degree Celsius. The major greenhouse gases are water vapour, which causes about 36-70 per cent of greenhouse effect; carbon dioxide which causes about 9-26 percent; methane which causes 4-9 percent; and ozone which causes 3-7 percent. Cloud also effect the radiation balance, but they are composed of liquid water or ice and have different effects on radiation from water-vapours.
Over past 50 years, the average global temperature has increased at the fastest rate in recorded history and experts see trend is accelerating. All, but one of the 16 hottest years in NASA’s 134-year record, have occurred since 2000. Global warming is long-term heating of Earth’s climate system observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere. Global warming is caused by several things, which include man-made or anthropogenic causes and natural causes. One natural cause is a release of methane gas from Arctic tundra and wet lands which is very dangerous to our environment. Pollution is the biggest cause of man-made problems e.g., burning of fossil fuels.
Global warming will have serious impacts on the environment and on society. Higher temperatures will cause melting of ice in Greenland and Antarctica which in turn will accelerate the rise of sea level. The rate, at which the global warming is expected to occur in 21st century, is faster than most plants and animals’ species will be able to cope with. It will also affect agriculture and water resources. Curbing dangerous climate change requires very deep cuts in emissions, as well as the use of alternatives to fossil fuels worldwide.
Ozone layer depletion is also one of the main concerns of the scientific community world over. The ozone layer protects the earth from the ultraviolet rays sent down by the sun. The excess of solar radiation is a threat to any form of life on earth. The impacts of global warming are being felt across the globe. Extreme heat waves have caused tens of thousands of deaths around the world in recent years. In an alarming sign of events to come, Antarctica has been losing about 134 billion metric tons of ice per year since 2002. This rate could speed up if we keep burning fossil fuels at our current pace and causing sea levels to rise several meters over the next 50 to 150 years.
In recent years, China has taken the lead in global-warming pollution, producing about 28 percent of all CO2 emissions. The United States comes in second. Despite making up just 4 percent of the world’s population, the US produces a whopping 16 percent of all global CO2 emissions-as much as the European Union and India (third and fourth place) combined. And America is still number one, by far, in cumulative emissions over the past 150 years. Globally, at United Nations Conference on Climate Change in Paris, 195 countries including the United States agreed to pollution-cutting provisions with a goal of preventing the average global temperature from rising more than 1.5 degrees Celsius above preindustrial times. Scientists say we must stay below a two-degree increase to avoid catastrophic climate impacts.
Under the terms of the Paris agreement, participating nations will meet every five years, starting in 2020, to revise their plans for cutting CO2 emissions. Beginning in 2023, they will also have to publicly report their progress.
The inter-governmental panel on climate change (IPCC) in its Climate Report 2018 summarizes the findings of scientists maintaining a temperature rise to below 1.5 °C through rapid and far-reaching transitions in energy, land, urban and infrastructure and industrial systems. Meeting the Paris target of 1.5 °C (2.7 °F) would require deep emissions reductions, rapid, far-reaching and unprecedented changes in all aspects of society.
In order to achieve the 1.5 °C target, CO2 emissions must decline by 45% (relative to 2010 levels) by 2030, reaching net zero by around 2050. Deep reductions in non-CO2 emissions (such as nitrous oxide and methane) will also be required to limit warming to 1.5 °C. Under the pledges of the countries entering the Paris Accord, a sharp rise of 3.1 to 3.7 °C is still expected to occur by 2100. Holding this rise to 1.5 °C avoids the worst effects but a warming of even 1.5 degrees will still result in large-scale drought, famine, heat stress, species die-off, loss of entire ecosystems, and loss of habitable land, throwing more than 100 Million into poverty. Effects will be most drastic in arid regions including the Middle East and the Sahel in Africa, where fresh water will remain in some areas following a 1.5 °C rise in temperatures but are expected to dry up completely if the rise reaches 2 °C.
We have to adopt easy, effective measures to make a difference that is conducive and beneficial to generations to come. Do not use cleaning products that are harmful to the environment and mankind and replace them with non-toxic products such as vinegar or bicarbonate. Buy local products to get fresh food free of nitrous oxide as maximum energy goes into processing, packaging, and shipping food of which about 30 to 40 percent just winds up in the landfill. Maintain air conditioners, as their malfunctions cause CFC (chlorofluorocarbon) to escape into atmosphere.
Avoid consumption of the most dangerous gases such as CFCs, halogenated hydrocarbon, methyl bromide and nitrous oxide detrimental to the ozone layer. Invest in energy-efficient appliances to reduce your own carbon footprint. Power your home with renewable energy. Use solar panels to charge batteries. Buy energy efficient and cost effective bulbs. Healing the planet starts in your garage, in your kitchen, and at your dining-room table. Change only happens when individuals take action.
Reduce water waste. Saving water reduces carbon pollution as it takes a lot of energy to pump, heat, and treat your water. So take shorter showers, turn off the tap while brushing your teeth, and switch to Water Sense labeled fixtures and appliances.
Pull the plug(s). This ‘idle load’ across all households adds up to the output of many power plants. So don’t leave fully charged devices plugged into your home’s outlets, unplug rarely used devices or plug them into power strips and timers.
Drive fuel-efficient vehicles like hybrids and fully electric vehicles and vehicles with full-serviced and proper inflated tires. Minimize use of cars by carpooling with others to pollute less and save money and environment as well. Airplanes account for 2 percent of all human induced carbon emissions and 12 percent from transportation sources. Bio fuels, lighter engines, aerodynamic designs, 3D printing of aircraft parts, and bug-proof coatings could boost fuel efficiency to reduce pollutants.
Global warming, a cause of concern
Dr Parshotam S Manhas