Anupama Nair
What is Global Warming? Global warming is an aspect of climate change, referring to the long-term rise of the Earth’s temperatures, mainly from human activities such as burning fossil fuels, that pump greenhouse gases into the atmosphere. The main gases that cause the greenhouse effect include carbon dioxide, methane, nitrous oxide, and water vapor (which all occur naturally), and fluorinated gases (which are synthetic). Global warming is expected to have far-reaching, everlasting and distressing consequences for planet Earth.
Josef Werne, a professor of Geology and Environmental Science at the University of Pittsburgh, stated “We can observe this happening in real time in many places. Ice is melting in both polar ice caps and mountain glaciers. Lakes around the world, including Lake Superior, are warming rapidly — in some cases faster than the surrounding environment. Animals are changing migration patterns and plants are changing the dates of activity”. Scientists project that extreme weather events, such as heat waves, droughts, blizzards and rainstorms will continue to occur more often and with larger intensity due to Global Warming.
We can see from the start of the millennium, each year from 2014 has been recorded as the hottest year in History. The year 2021, broke all previous records. Most of the countries in Northern Hemisphere, recorded record temperatures in June itself. A heat dome was created in United States and Canada in June, causing temperatures as high as 47°C. I am not talking about Delhi or Lahore, but Canada, a place where Summers are always pleasant. I shudder to imagine what the temperatures will be in Australia and South Africa, this summer from November—March.
What is heat dome? A heat dome is formed when the atmosphere acts as a lid or cap and traps hot ocean air beneath it. It is an area of high pressure stuck over a region. According, to the National Oceanic and Atmospheric Administration, heat dome formation is more likely during the La Niña years. This year is unfortunately, a La Niña year. Due to the temperature discrepancy, winds blow dense, tropical western air eastward. That warm air eventually becomes stuck in the jet stream, a circulation of air that travels counterclockwise around the globe, and ends up on the Western Coast of the United States. Heat dome works like a lid on a pot, trapping hot air mass underneath. And this feature is often blamed to be responsible for long-lasting and deadly heat waves around the world. Often a very significant heatwave develops underneath with temperatures well above normal, challenging some heat records.
The heat waves bring in a lot of sunlight and sinking air that heats up as it compresses. Western Canada usually experiences such heat waves in July or August beginning, however in Summer 2021, it had occurred as early as June. Lytton, a town in British Columbia recorded a temperature of 47°C on 28th June 2021 which was the highest temperature ever recorded in Canada as per NASA's Earth Observatory. This year, record heat was reported in Europe too. Countries like Denmark and Sweden reported sweltering heat.
As you are aware, countries closer to the equator (zero degrees latitude) have warmer temperatures year-round compared to countries farther north or south of the equator. Countries that are further north in the Northern Hemisphere or south in the Southern Hemisphere experience four seasons and a wide range of temperatures, including significantly colder temperatures in the winter. Because of the Earth's tilt on its axis, the polar regions receive the sun's rays at a slanted angle, however, the equator receives the rays more directly over a smaller area, making the rays more concentrated and hotter.
Scientists attribute these change in weather patterns to climate crisis aggravated by human actions. “Such extreme weather events are likely to be more frequent and severe”, warned World Meteorological Organization in July this year. “Extreme precipitation has been increasing globally due to human-induced climate change”, stated a new research conducted by the University of California. “In a summer already full of extreme weather, it's the heat waves roasting hundreds of millions of people across three continents – America, Europe and Africa and are confirming a grim climate prophecy for many experts” said a weather expert.
Did you know even a minor increase in the temperature across the globe can have disastrous effect. You will ask what difference a minor rise in temperature would mean to the world, and you would be astonished to know there would be a lot of difference in the state of the planet when there would be a rise of 1.5°C and 2°C.
Time and again it has been stressed by the world leaders that global warming needs to be reduced to avoid the Earth's temperature rising by 2°C. The temperature needs to be limited to 1.5°C. In the 2015 Paris Agreement many countries committed to limit the average temperature of the planet. The moot point is after 6 years, has it been done? No would be the answer as the extreme heat, floods, draughts, wild fires in 2021 and 2022 are any indication.
Scientists have been warning us again and again that we need to control our CO2 emissions by 2030 and reach the net-zero level so as to prevent the global temperatures to surge by 2°C. It is an ambitious task that the scientists, financiers and activists of the world have been discussing and debating in COP26. Will it be a success that remains to be seen?
The global temperatures have already risen by almost 1.1°C above the pre-industrial levels. Every four decades were hotter than the previous decades since 1850. Daniela Jacob, a Climate Scientist said, “We never had such global warming as seen in a few decades. Half a degree means much more extreme weather, and it can be more often, more intense, or extended in duration”.
What she said seems to be true as “it is at this very temperature the global floods, torrential rains and extreme monsoon in the Indian Subcontinent has hit the world. Many wildfires, and massive glacier melting has been experienced by the world due to this rise in temperature. China, Indonesia, Australia, Greenland were all sufferers of this penalty”. As Rachel Warren from the University of East Anglia said, “Climate change is already affecting every inhabited region across the globe”.
The clear message is if we are not careful and take care of our mother Earth, the future is going to be a climatic disaster.
