New Delhi:

The month of September surpassed its heat record by 0.5°C and was hotter than the pre-industrial average by a whopping 1.75°C, according to weather agencies who said the year is shaping up to be the warmest year on record in what they described as an “ominous” sign of how the climate crisis is taking effect.

Overall, the global mean temperature to date was estimated to be 0.52°C above the current average, and 1.4°C above the pre-industrial average, showed data from EU’s Copernicus Climate Change Service. Scientists have warned of catastrophic natural calamities if the world warms to above 1.5°C on average compared to the pre-industrial era (1850-1900).

Some of the strongest flooding and heat spells have been recorded this year, coupled with record high sea surface temperatures and unprecedented shrinkage of polar ice. And scientists fear more is to come since a planet-heating phenomenon known as the El Nino is only just taking hold.

“This continues an extended streak of extraordinary land and sea-surface temperatures and is an ominous signal about the speed with which greenhouse gases are changing our climate,” the World Meteorological Organisation (WMO) said adding that 2023 is now on track to be the warmest year on record.

According to the EU’s Copernicus Climate Change Service (C3S) implemented by the European Center for Medium Range Weather Forecasts, September had an average surface temperature of 16.38°C. This was 0.5°C above the temperature of the previous warmest September, in 2020.

The global temperature for January-September 2023 was 0.05°C higher than the equivalent period in 2016, which was the warmest year so far, and 1.40°C higher than the pre-industrial average (1850-1900).

“Since June, the world has experienced unprecedented heat on land and sea. The temperature anomalies are enormous – far bigger than anything we have ever seen in the past. Antarctic winter sea ice extent was the lowest on record for the time of year. What is especially worrying is that the warming El Nino event is still developing, and so we can expect these record-breaking temperatures to continue for months, with cascading impacts on our environment and society,” said WMO secretary-general Petteri Taalas in a statement on Thursday.

“The unprecedented temperatures for the time of year observed in September — following a record summer — have broken records by an extraordinary amount. This extreme month has pushed 2023 into the dubious honour of first place — on track to be the warmest year and around 1.4°C above pre-industrial average temperatures. Two months out from COP28 — the sense of urgency for ambitious climate action has never been more critical,” said Samantha Burgess, deputy director of the C3S in a statement.

HT reported on September 22 that there was about a 95% chance that 2023 is likely to be the warmest or the second-warmest year on record, according to National Oceanic and Atmospheric Administration (NOAA).

Between January and August, global land and ocean temperatures were 1.06°C above the base period of 1991 to 2020, making it the second-warmest January-August period in history.

El Nino conditions are expected to continue through the upcoming winter. There is a greater than 95% chance of El Nino persisting through January-February-March (2024) and around a 70% chance of it staying strong by November-December-January, NOAA scientists had forecast last month.

“El Nino is becoming a severe event. Normally El Nino causes additional warming in addition to global warming due to greenhouse gases. Therefore, in El Nino years we should expect abnormal temps every where especially in tropics. We also should see whether the global warming signal due to greenhouse gases is getting accelerated. There could be the influence of Multidecadal oscillation of the oceans especially the Atlantic Ocean,” said M Rajeevan, former secretary, ministry of earth sciences.

El Nino has a strong influence on the southwest monsoon in India. El Nino years are characterised by an unusual warming of waters in the eastern equatorial Pacific, which has a high correlation with warmer summers and weaker monsoon rains in India.