What El Nino And World Crossing 1.5°C Global Warming Threshold Could Mean For India

The world is very likely to see its warmest year ever on record in the next five years, according to the World Meteorological Organisation (WMO). The United Nations agency, in a statement last week, said that there was a 98% chance that at least one year between 2023 and 2027 will be warmest on record. It also predicted a 66% likelihood that the annual average near-surface global temperature between 2023 and 2027 will temporarily be more than 1.5°C above pre-industrial levels for at least one year.

A warming El Nino that is predicted to form in the coming months, coupled with human induced climate change, will drive up temperatures into "uncharted territory", the WMO said. Eight of the hottest years on record were in the last decade, with the hottest being 2016, another El Nino year.

What does this mean for India? The Core spoke to experts to understand what to expect.

A Rise In Extreme Weather Conditions

The Indian subcontinent is in a very vulnerable location, said AVM GP Sharma, president (Meteorology and Climate Change), Skymet Weather. "The tropics are as such more vulnerable than other locations like at mid and high latitudes, and we in India have a coastline of over 6,500 kilometres – east coast and west coast. And we have varied geography, varied geographical disbursement, varied geographical distribution as far as the landmass is concerned and we are more vulnerable," he said.

Since all weather events are connected to heat and rise in temperature, the impending El Nino could spell doom for many regions in India.

However, we have to be careful when it comes to long-term forecasts, because these "mostly depend on describing where the CO2 concentrations and greenhouse gases will go in the next five years," said Raghu Murtugudde, an earth system scientist and visiting professor at IIT Bombay's climate studies programme.

"Global mean temperature increase is linearly related to the cumulative CO2 since the industrial revolution. To the extent that we can say the CO2 and the greenhouse gas increase will continue for five years approximately at the same rate, then we can say the linear warming over the next five years will cross the 1.5 degree threshold," he said. But these models are not capable of predicting what will happen locally and regionally, he added. "So global warming will continue to act on top of the natural variabilities like El Nino and La Nina."

Not just heat and affected monsoons, El Nino could also trigger extreme weather events.

Akshay Deoras, who is a research scientist at the National Centre for Atmospheric Science & Department of Meteorology, University of Reading, UK said, "In such a scenario, the vulnerability to extreme weather conditions would go up in India, including, for example, more persistent, frequent, and intense heat waves and extreme hydrological events during the two monsoon seasons."

This does not mean that each of the El Nino years will be saturated with extreme weather events of all types. This is because natural and interannual variability of weather systems will still play an important role. "However, under favourable meteorological conditions, the possibility of witnessing extreme weather events will be much more than what it is at present," said Deoras.

Rise In Heatwaves

"The rise in temperature is a huge gamut which involves everything - it can trigger glacial lake outburst floods (GLOFs), it increases the frequency of forest fires, it amplifies the energy crisis, increases electricity demand, power outages," Sharma said, adding that the rise in heat would also take a toll on the health and agriculture sectors.

The coastlines will especially be affected as they are vulnerable. The rise in temperature could lead to a rise in sea level too because of glacial melt or ice melt. India has a long coastline and any rise in sea level increases the risk for these regions.

Two prominent heatwave zones in India are expected to be the most vulnerable to the temperature rise and subsequent heatwaves, explained Deoras. "The first zone comprises of northwestern plains of India such as Rajasthan, Punjab, Haryana, Delhi-NCR, Madhya Pradesh, whereas the second zone comprises of eastern states in the Indo-Gangetic plains such as Bihar and West Bengal and surrounding states such as Jharkhand, Odisha, Chhattisgarh, Andhra Pradesh, and eastern Maharashtra. Hilly states in the north often see prominent hot weather events, so they will also be in the most vulnerable category," he said.

Erratic Monsoons

In addition to heatwaves, the rising temperatures could also lead to altered rain patterns, as heat increases the atmosphere's capacity to hold moisture. Murtugudde said that we were going from a La Nina winter to an El Nino summer - the worst case scenario for monsoons.

"With that increase in the capacity of holding moisture, what it amounts to is frequent sharp showers and increased intensity for short duration," Sharma pointed, adding that this in turn will affect food production.

The predicted rise in heat could cause an early depletion in the snow cover in the spring season itself, Deoras said. "Increased possibility of a warm winter season and corresponding changes in the activity of western disturbances could also modulate the snow cover during the winter season," he said.

"People living in high population density and poor ventilation areas in the above regions have a larger risk of getting impacted by high temperatures than those living in good ventilation areas," said Deoras. "Besides, the fraction of population dependent on outdoor jobs, intense indoor mechanical jobs (e.g., industries), and those requiring to commute a significant distance every day will be at a larger risk than others," he said.

Are We Prepared?

India invested in better weather forecasting systems in the last few years, prompting better weather predictions. This means that people can be warned in case of extreme weather events in time to prepare.

Deoras said, "It is now possible to issue specific warnings at least one week in advance." However what is lacking is that high temperatures and heatwaves are still not taken seriously by many despite such events having a potential to be fatal, Deoras explained.

More efforts need to be taken to convert weather forecasts into early warning systems and advisories, said Murtugudde. "Even when they are done, to some extent, the last mile problem still remains," he said, explaining that SMS warnings for heat waves or heavy rains may not always reach everyone.

However, at the end of the day, one can't really control the weather, Sharma said. "What we can control is human induced climate change," he said, adding how mitigating climate change effects by controlling emissions might help. "If we start that effort today, the results will show only after 15-20 years," he said.