New York: About 560 million people along India’s 7,500-km long coastline are at risk of inundation. More floods are likely along the Ganga and Brahmaputra. The monsoon will become more uncertain. Stronger cyclones may strike the western coast.
These are some of the predictions made for India by experts interpreting the findings of the latest climate-change report, released on September 25, 2019, by the Intergovernmental panel on climate change (IPCC), the United Nations (UN) body that assesses the science related to global warming.
Titled, “The Ocean and Cryosphere in a Changing Climate”, the IPCC report evaluates climate change on the oceans, which blanket 71% of the earth’s surface, and the cryosphere–frozen areas, such as glaciers and ice sheets, which cover 10% of the planet.
For India, the major impact will come from the melting of ice in the Hindu Kush region of the Himalayas, which holds the largest reserves of water, in the form of ice and snow, outside the polar regions and is the source of 10 of the largest rivers in Asia.
“These systems, therefore, are the economic engines of the region, especially due to the large freshwater reserve, biodiversity and natural resource support that it provides for the billions of people living downstream,” Anjal Prakash, coordinating lead author of the report and associate professor, Regional Water Studies, TERI School of Advanced Studies, told IndiaSpend. “What happens to Himalayan glaciers is directly connected to what happens to over 2 billion people living in Asia.”
Since the beginning of the industrial era (1850), the world’s temperature has risen by 1.1 deg C. If emissions continue at the current rate, then the earth is headed for a 3 deg C temperature rise.
The UN Secretary General Antonio Gueterres has asked for a 45% cut in global carbon emissions by 2030. The remaining emissions must be soaked up by “carbon sinks” such as forests, oceans and soil, and reduced to what is called “net-zero” by 2050 to contain global temperature rise to 1.5 deg C.
The IPCC report said climate change is causing glaciers to melt at an “unprecedented” rate, leading to a rise in frequency of cyclones and changing global rainfall patterns.
Close to 670 million people worldwide live in coastal areas and 65 million in small-island nations. Another 670 million people live in high mountains. The impact of the changes in oceans and glaciers is likely to affect one in every five persons living on the planet.
The IPCC report has been ratified by 195 countries which means that it represents global consensus, but experts said this makes it a conservative estimate. The actual impact of climate change could be worse.
Indian lives, livelihoods at risk
India’s 7,500-km long coastline is dotted with major cities, such as Mumbai, Kolkata and Chennai, all at risk of flooding. Those living along the coastline are already moving away, as sea level rises, as IndiaSpend reported from the Sundarbans in West Bengal and Honnavar in Karnataka.
Stray adaptation is evident, but that must become government policy, if livelihoods and lives are to be saved, experts said.
“In Odisha many cyclone events are occurring but the states have geared to evacuate people,” said Prakash. “It is one of the good examples where the state has worked really well to adapting to the changing climate patterns. But imagine all cities and all the coastal states will have to keep doing this in the future and (imagine) how much it will cost the state exchequer to manage these events.”
The rising seas will move inland, make fields unfit for agriculture and drinking water sources along the coastline saline, something that is already happening, as IndiaSpend reported from Odisha in February 2019.
The annual south-east monsoons, on which more than half of India’s farms depend because they are unirrigated, are likely to become more erratic than they already are. That is because of changing global weather patterns, such as the periodic Pacific-warming phenomenon known as the El Nino, which is likely to double in frequency over the century.
“For India, which depends on the monsoon rains, a moderate El Niño in itself can result in a deficit and erratic monsoon,” another IPCC-report co-author Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology (IITM), told IndiaSpend. “So, when an extreme El Niño hit the world in 2015-16, India reeled under back-to-back droughts. Ethiopia and South Africa had one of the worst droughts in 50 years and severe heatwaves, resulting in a 9-million-tonne cereal deficit, leaving more than 28 million in need of humanitarian aid.”
These extreme El Niños are likely to increase from one event every 20 years, as scientists recorded over 99 years to 1990, to one every 10 years by the turn of the century, which means the monsoons may witness large-scale fluctuations.
The fate of the oceans is linked to the great ice sheets that cover the poles.
As more ice melts, sea levels rise
Between 2006 and 2015, the Greenland ice sheet lost ice at an average rate of 278 gigatonne (Gt) every year, enough to cause sea levels to rise by 0.7 mm, said the IPCC report.
Over 52 years to 2019, the June snow cover on land in the Arctic declined by 13.4% per decade. Between 1979 and 2018, sea ice in the Arctic decreased by 12.8% per decade, a change not seen for at least 1,000 years.
This melting of ice is pushing up sea levels. Sea levels rose 15 cm, or roughly the size of a 500 ml coke bottle, over the 20thcentury alone. Currently, the seas are rising twice as fast–3.6 mm per year–and increasing.
By the turn of the century sea levels could rise up to 60 cm, or equivalent to four 500 ml bottles of coke atop each other, if global temperature rise is restricted to 2 deg C. It could be higher if global warming goes beyond that, the IPCC report said.
Not only are the seas rising, they are warming, and that has a range of consequences.
Rise in sea temperatures
“The global ocean has warmed unabated since 1970 and has taken up more than 90% of the excess heat in the climate system,” the IPCC report said. While the global air temperature has risen by 1.1 deg C since the pre-industrial era (1850), ocean temperatures have risen by 0.8 deg C.
Since 1993, the rate of ocean-warming has doubled. Marine heatwaves have doubled in frequency since 1982 and are increasing in intensity.
Marine heat waves can devastate sea life.
“Coral reefs occupy only 0.1% of the planet’s surface, but are home to 25% of all the animals found in the ocean,” said Koll of the IITM. “Corals have a specific range of temperatures that they can survive in, and the frequent occurrence of marine heat waves are killing them and the ecosystem around them.” This shift in temperatures is likely to affect fishing communities.
“Reducing other pressures, such as pollution, will further help marine life deal with changes in their environment, while enabling a more resilient ocean,” said Hans-Otto Pörtner, co-chair of IPCC Working Group II.
The warming of the oceans also brings with it the possibility of more severe cyclonic storms.
“With a rapidly warming Indian Ocean, these severe cyclones are projected to increase in number, and we cannot neglect the possibility of these cyclones making landfall over the west coast of India,” said Koll.
Cooling and adaptation
The planet can address global warming by reducing global emissions to rein in rising temperatures and help local communities adapt better.
“We will only be able to keep global warming to well below 2°C above pre-industrial levels if we effect unprecedented transitions in all aspects of society, including energy, land and ecosystems, urban and infrastructure as well as industry,” said Debra Roberts, Co-Chair of IPCC Working Group II. “The ambitious climate policies and emissions reductions required to deliver the Paris Agreement will also protect the ocean and cryosphere–and ultimately sustain all life on Earth.”
“If one country takes measures it won’t solve the problem,” said Prakash of the TERI School of Advanced Studies. “Countries have to collaborate and coordinate for climate action. They have to come together at a global level to flight the unprecedented climate crisis in the history of humanity.”
(Shetty is a reporting fellow with IndiaSpend and reporting from the United Nations on a Reham al-Farra Memorial Journalism Fellowship.)
Courtesy: India Spend