With the mercury touching 45 degree Celsius, are we heading for a disaster? Parts of Sunderban submerging into the sea, apple orchards in Garhwal under fungal trap, torren­tial rains in Rajasthan, more than three billion trees destroyed by the wood eater insects in Alaska, submerging Indonesian islands, Southeast Asian countries stricken by dengue, the collapsing ice-shelves, receding glaciers, unforeseen heat waves in Europe: These are some scary news doing the round these days. Is it the result of global warming?

Global warming is an increase in the average tempera­ture of the earth’s surface air and oceans due to the human-induced greenhouse gases. Generally, it refers to the increas­ing temperature of earth’s climate in recent decades and im­plies human interference. In the process of unregulated rapid industrialization and deforestation, the increasing concentra­tions of anthropogenic (human-induced) greenhouse gases such as carbon dioxide, methane, ozone, nitrous oxide, clorofluro carbons etc in the atmosphere amplifies the ‘Green­house Effect’, which leads to the ‘global warming’.

All the human-induced Greenhouse gases have badly hit earth’s self-regulatory mechanism to maintain the ideal tem­perature and the Albedo, an index that quantifies earth’s effi­ciency of reflecting the radiation/energy back into the outer space as opposed to that absorbed by the atmosphere.

If the global community does not wake up to the warn­ing collectively to tackle the situation, the global warming will keep on melting down the glaciers and raise the sea level. Ultimately, the low altitude islands and coastal regions will drown into the sea with all their biodiversity and anthropo­logical assets.

Partial submersion of low altitude islands and coastal habitations will lead to the damage of coastal ecology. Shrink­ing of agricultural land will ultimately create food crisis. Changes in rainfall patterns, increased intensity, and frequency of extreme weather events, heavy precipitation of water will lead to water scarcity/drought in one region and floods in another. The rising temperature may add a range of new vec­tors of diseases like malaria and dengue.

The extreme weather might reduce global gross domes­tic product up to 1 per cent, and in a worst scenario global per capita consumption could fall by 20 per cent.

Insurers, reinsurers, and banks will be trapped under fi­nancial crisis. Other economic sectors may face difficulties. Moreover, the developing countries will face greater economic risks than the developed one.

Global average temperature around Earth’s surface rose by around 0.74 °C during the past century. Even if green­house gases were stabilized at the present day levels, a fur­ther warming of about 0.5 °C (0.9 OF) would still occur. Earth’s surface temperature is likely to increase by 1.1 to 6.4°C by 2100. Sea level will rise by 0.36 to 2.5 ft by then.

Approximately 18 per cent to 35 per cent of a sample of 1.103 animal and plant species would be extinct by 2050. The oceanic organisms and ecosystems adapted to a narrow range of pH will be extinct due to ocean acidification and decrease in the pH. Increased atmospheric level of carbon dioxide increases the amount of carbon dioxide dissolved in the oceans. It would disrupt food webs and hit the human societies that depend on marine ecosystem services.

After carbon dioxide, the principal greenhouse gas, meth­ane is the second most important. Methane is more than 20 times as effective as carbon dioxide in trapping heat in the earth’s atmosphere. Flooded fields and primarily the paddy fields release huge volume of methane gas to the atmosphere.

Thermal power generation is the other most important source of carbon dioxide. Coal contains about 80 per cent more carbon per unit of energy than gas does, and oil con­tains about 40 per cent more.

Oceans and rainforests naturally produce nitrous oxide, another greenhouse gas commonly known as laughing gas. It is hugely emitted during the production of nylon, nitric acid, and fertilizers.

Deforestation is responsible for 25 per cent of all carbon emissions, by the burning and cutting of about 34 million acres of trees every year. We are losing millions of acres of rainforests a year, the equivalent in area to the size of Italy.

The destruction of tropical forests alone is throwing hun­dreds of millions of tons of carbon dioxide into the atmos­phere every year. Globally we are also losing temperate for­ests which accounts for an absorption rate of two billion tons of carbon annually. In the temperate forests of Siberia alone, the earth is losing 10 million acres per year.

Awareness and energy-efficiency are the mantras to mini­mize the impact. When replacing home appliances, use en­ergy efficient models. Replacement of incandescent light bulbs with compact fluorescent bulbs will make a big difference. Place an insulating cover around water heater. Insulate walls and ceilings, and lower heating bills. Keep the door of the room shut not in use while cooling/heating your house. Al­ways carry your own cloth/jute bag while shopping for gro­ceries. Say no to plastic bags. Encourage your family mem­bers and neighbours to take public transit whenever possible.

Save trees and plant as much as possible. It is a cost-efficient and easy way to slow global warming. Proper maintenance of your vehicles and efficient driving, encouraging community carpooling will save fuels and check the emission of green­house gases. Inform the concerned enforcement agency e.g. traffic police if you find a vehicle with heavy emission in the traffic. Start a debate within your organization to use as much units of renewable energy sources as possible for internal consumption.