Mercury rising: Global warming sends stark signals

Umbrellas, cover-all scarves and water bottles were out in full force as visitors to the Merlion Park braved a hotter-than-usual December in Singapore in 2018.
Umbrellas, cover-all scarves and water bottles were out in full force as visitors to the Merlion Park braved a hotter-than-usual December in Singapore in 2018.PHOTO: ST FILE

Singapore experienced eighth warmest year on record last year while December was second warmest ever

Found yourself turning on the air-con more than usual last month?

Thanks to global warming, last December was the second warmest ever in Singapore, with the monthly mean temperature of 27.6 deg C just 0.1 deg C lower than in December 2015 - the hottest December on record.

Consistently above average temperatures, punctuated by a brief cool spell, made last year the eighth warmest year on record here.

The mean annual temperature was 27.9 deg C, or 0.2 deg C warmer thanthe 27.7 deg C in 2017, the Meteorological Services Singapore (MSS) said yesterday in its review of 2018 weather and climate. The warmest year on record for Singapore is 2016, when the annual mean temperature was 28.4 deg C.

Deputy principal research scientist Raizan Rahmat at the Centre for Climate Research Singapore, which is part of MSS, said last year's higher temperatures were part of an ongoing uptrend that can be attributed to global warming.

"Temperatures are expected to continue rising above the natural range of climate variability due to the increasing influence of on-going and future global warming, and to some extent urbanisation," Mr Raizan said.

The second half of last month was particularly warm, MSS said.

On Dec 28 and 30, the Changi climate station recorded a daily maximum temperature of 33.8 deg C, tying the record set on Dec 2, 1948, for a December day since Singapore started keeping records in 1929.

MSS highlighted that Singapore's 10 warmest years were recorded in the past 25 years, and that eight of these 10 had occurred since 2001.

  • 27.9

  • The 2018 mean annual temperature in deg C, which was 0.2 deg C warmer than the 27.7 deg C in 2017.

The period between 2009 and 2018 was also the warmest decade for Singapore, with a mean temperature of 27.89 deg C. This eclipsed the previous record by 0.02 deg C in the 1997-2006 period.

These are signs of the long-term, continuous effect of global warming, said Mr Raizan, adding: "How much hotter Singapore will be in future decades will largely depend on the rate of global warming."

 
 
 

Although MSS noted that Singapore's overall temperatures are on the rise, the weather has also been fairly temperamental.

Last year, a monsoon surge from Jan 10 to 14 brought five consecutive days of cool weather, with the daily minimum temperature dipping to 21.2 deg C on Jan 14 - the longest cool spell in at least two decades.

MSS also said this was rare and a form of extreme weather but not unprecedented. In December 1991, a cool spell of similar duration sent the daily minimum temperature dipping below 23 deg C.

Though 2018 was largely a neutral year for El Nino, which is associated with hot and dry conditions, with "no significant influence on Singapore's climate", weak La Nina conditions prevailed in the first quarter.

Still, Singapore was not spared drastic fluctuations in weather conditions - with torrential rain, hail storms and strong winds experienced in the first half of 2018.

Last Jan 30, intense thunderstorms brought rain and even hailstones over parts of northern Singapore. A day later, strong wind gusts from a waterspout off Singapore's east coast sent small boats and other objects flying.

At other periods, heavy rains and strong wind gusts from intense thunderstorms triggered flash floods, toppled trees and caused damage to property.

On March 30, strong winds from an intense thunderstorm uprooted trees and caused substantial damage to farms in the Lim Chu Kang area. And a wind gust measuring 133.3kmh recorded at nearby Tengah that day was the strongest in eight years.

A version of this article appeared in the print edition of The Straits Times on January 16, 2019, with the headline 'Mercury rising: Global warming sends stark signals'. Print Edition | Subscribe