Global temperature continued to be warmer in October with even the sea surface temperature for the month being the highest on record, says an European Union’s weather observation agency.

“October 2023 was the warmest October on record globally, with an average surface air temperature of 15.30°C, 0.85°C above the 1991-2020 average for October and 0.40°C above the previous warmest October, in 2019,” said Copernicus, the EU space programme’s earth observation component.

The agency said the global temperature anomaly last month was the second highest across all months in its dataset, behind September 2023. As a whole, October was 1.7°C warmer than an estimate of the October average for 1850-1900, the designated pre-industrial reference period.  

Worries for India

For January to October, the global mean temperature for 2023 is the highest on record - 1.43°C above the 1850-1900 pre-industrial average, and 0.10°C higher than the ten-month average for 2016, currently the warmest calendar year on record.  

The Australian Bureau of Meteorology said global sea surface temperatures (SSTs) were highest on record for their respective months during April to October.

The development is of concern to India, particularly its agriculture sector, as at least 67 per cent of the 712 districts from where data were received either had no or deficient or large deficient rainfall since October 1. 

According to the US National Centers for Environmental Information (NCEI), there is a more than 99 per cent chance that 2023 could rank as the warmest year on record globally. 

Record sea surface temp

The National Oceanic and Atmospheric Administration of the US, said over 20 per cent of India is reeling under drought. The India Meteorological Department said October received the sixth-lowest rainfall since 1901. 

 The average sea surface temperature for October was 20.79°C, the highest on record for October, Copernicus said.  

“El Niño conditions continued to develop in the equatorial Pacific, although anomalies remain lower than those reached at this time of year during the development of the historically strong 1997 and 2015 events.” it said. 

For the sixth consecutive month in October Antarctic sea ice extent remained at record low levels for the time of year, with a monthly value 11 per cent below average, the agency said.  Arctic sea ice extent reached its seventh lowest value in October, at 12 per cent below average. October was drier than average in regions of central and easternmost Asia, it said. 

El Nino, positive IOD continue

The Australian Bureau of Meteorology said El Nino and positive Indian Ocean Dipole (IOD) events continue. “The IOD index is +1.55 °C for the week ending November 5, 2023. The weekly IOD index values for this event have been the second-highest since records for the Bureau SST dataset began in 2001, with the highest values occurring in the strong positive IOD event of 2019,” it said.

Sea surface temperatures (SSTs) for the week-ended November 5 were warmer than average in much of the western half of the tropical Indian Ocean. 

Conversely, the eastern pole of the IOD, under which India falls, was cooler than average, with a notable area of cooler waters extending off the coast of Java, it said.  

The positive IOD event will likely continue into December, the Bureau of Meteorology said, pointing to results of all international climate models surveyed by it. 

The Australian weather agency said when a positive IOD and El Nino occur together, they create a “typically stronger” drying effect.  In the atmosphere, cloud, wind and pressure patterns are consistent with El Niño conditions. 

Climate model forecasts indicate some further warming of the central to eastern Pacific is likely, with SSTs remaining above El Niño thresholds into the early southern hemisphere autumn 2024, it said.