The Safe Limit for Temperature Rise is Slipping Out of Reach

The first part of the IPCC’s Sixth Assessment Report on climate change released August 9 raises alarming warnings about rising global temperature. The earth’s average temperature is rising faster than estimated. At current rates in the next 20 years it will cross the 1.5°C threshold 10 years sooner than predicted.

The report unequivocally shows the increase in the average temperature of the land, oceans and atmosphere is due to human activity. It warns of an increase in average sea level by up to 2 metres by the end of this century. It also warns that the Arctic is likely to be ‘practically sea ice-free’ in the summer at least once before 2050.

Scientists confirm that each decade in the last four decades has been hotter than the previous ones: after 1970 the temperature began to rise sharply. Looking to the future, extreme temperatures are expected in multiple geographical locations where temperatures could rise several degrees above the average, and the frequency of heat waves will increase rapidly. Rising ocean water temperature will further increase the probability of marine disasters.

Prolonged summers will inevitably impact the rainfall patterns and growing heat waves will adversely affect agriculture. Rising temperature will cause polar ice caps and glaciers to melt, raising the sea level, a major problem for coastal villages, cities, islands and fertile river deltas near the sea that are crucial to the production of food.

According to a special report of the IPCC titled ‘Climate Change and Land’ released in 2019, human activities have changed 70 per cent of the earth’s (ice-free) surface.

The oceans are also being severely damaged by human activities. According to a study by Harvey, two-thirds of the ocean area is under extreme pressure from human activities. The amount of acidic matter and pollutants in the oceans are increasing which is causing various diseases to marine life, hence they are becoming extinct in large numbers. In the last week of June 2021, more than a billion marine animals died due to a ‘heat dome’ created by the heat wave in Canada and the western United States.

According to a study by Singapore's Nanyang Technological University, a 0.5 metre rise in sea level could increase the risk of tsunamis by 2.4 times and a one metre rise by 4.7 times. A one-degree rise in sea water temperature would increase the wind speed in a hurricane by 5 per cent and a high-speed hurricane would wreak havoc, according to a study by Daniel Levitt and Nico Camnada.

The report makes it clear that limiting the rise in temperature to 1.5 degrees (the safe limit set by the Paris Climate Agreement) is slipping out of reach. Due to the rapid emission of greenhouse gases in the last century the average temperature of the earth has already risen by 1.1 degree Celsius since the preindustrial period.

Even a part of a degree of temperature rise is very important. With every one degree rise in temperature, there will be a 7% increase in the intensification of extreme rain events. A special IPCC report in 2018 indicated that a mere half-degree Celsius rise in temperature could raise sea levels by up to 8 feet, causing damage to human settlements of 3 to 8 million people.

At the same time, 410 million people in the cities will suffer from water scarcity. And 18% of insects, 16% of flora and 8% of four-legged animals will disappear from the face of the earth forever.

Similarly a one degree Celsius increase in temperature is likely to increase the frequency of heat waves by 5 times and a 2 degree increase by 14 times. Rising temperature is also increasing the frequency of related natural disasters such as droughts and wildfires, as seen in California, in Lytton, a small town in Canada, and in Greeca to recall a few recent devastating events.

Global warming is also increasing the incidence of droughts. According to a 2020 report by the Council on Energy, Environment and Water 68% of India’s land area is facing drought-like conditions. Far off California too is currently suffering from prolonged drought in an area where drought used to occur only once a decade.

The incidence of floods is also increasing. In July 2021 western Europe experienced the worst floods in many decades as hundreds of people were killed in Germany, Belgium, Luxembourg, Switzerland and the Netherlands due to heavy rains. In China, flash floods in Henan province in the same month killed at least 300 people affecting more than 1.3 million.

The report indicates that India will also continue to be prone to natural disasters resulting from rising sea levels and rising temperatures. These disasters will affect people living in its coastal areas. With the rise in sea water temperature, the number and intensity of cyclones in the Bay of Bengal and the Arabian Sea will increase.

The report also finds that tropical cyclones are migrating poleward, hence as they track northwards along the Indian coast and mainland, and last longer their destructive impact is likely to increase.

We have very little time left to save the earth and its people from the damage caused by these unnatural disasters. Deforestation and greenhouse gas emissions have to drastically be reduced to limit the damage to a 1.5 degree rise. But instead of declining, the use of fossil fuels is still growing at a rate of 2% per year.

China, the United States and India, which currently emit more greenhouse gases into the atmosphere than any other country of the world, and are also responsible for large swathes of deforestation, should shut down their coal-fired thermal plants as soon as possible. India, China and the United States must quickly switch to renewable energy sources for economic growth, and cut their carbon emissions as fast as European countries have done.

Although India has a very small share of global greenhouse gas emissions (2.65 gigatons) compared to China (10.1) and the United States (5.4) this does not mean that India does not require any action to reduce greenhouse gas emissions or deforestation.

According to the Council on Energy, Environment and Water 75% of the districts in India are suffering from one or the other kind of natural disasters. The steps to be taken to deal with climate change are in the interest of our country and its people.

The IPCC report comes just six months before the 26th session of the United Nation led Conference of the Parties (COP26). There is an urgent need for the leaders of all world governments to come up with a solid plan for the reduction of greenhouse gases.

So far, 90 countries have submitted their plans to the United Nations to cut greenhouse gas emissions, but that would reduce emissions by only 2.3 billion tonnes by 2030. The need of the hour is a reduction ten times greater, or our planet will warm by more than 1.5 degrees Celsius.

China, the United States and India must play their part in reducing emissions and deforestation as industries in these three countries emit 50% of the total emissions into the atmosphere.

All the nations of the world must unite and take firm and concrete steps. These include changing the current economic development model and people’s way of life, as well as ensuring clean technology and financial assistance to the developing and least developed countries by the developed countries.

Dr Gurinder Kaur is Former Professor, Department of Geography, Punjabi University, Patiala