PETALING JAYA: It’s hard to imagine that events happening in the Arctic can impact weather in Malaysia.
However, according to one expert, what’s happening in the Arctic due to global warming is complicating the weather in our country.
National Antarctica Research Centre meteorological expert Prof Datuk Dr Azizan Abu Samah said that in the Arctic, there is a strong circumpolar wind that basically isolates the cold polar air from meandering into the Siberian High.
“What complicates it is what is happening in the Arctic due to global warming.
“If this circumpolar wind is weakened, it will meander and result in a colder Siberian High.
“This will make the cold surge which originates from the Siberian High stronger and more frequent – even under El Nino influence.
“The wind, as it crosses from Siberia to here, gets warmed up by the South China Sea, and also picks up moisture from the sea to dump on our coast,” he explained in an interview.
“More research needs to be done on this, and this is what my group is undertaking.”
Numerous studies have indicated that the warming in the Arctic has been much faster than in the rest of the world – up to nearly four times the global average – and the sea ice is declining by more than 10% every decade.
“Arctic warming due to global warming has added some uncertainty in the behaviour of weather and climate in our region,” said Prof Azizan.
On the increase in the average rainfall for Peninsular Malaysia and Sarawak between 2020 and 2022, he said the data corresponded with the influence of La Nina.
“During La Nina, the expected rainfall is about 10% to 20% above the average rainfall.
“The increase seen is within the scope of influence due to La Nina,” he said.
Data from the Irrigation and Drainage Department showed that the average rainfall for Peninsular Malaysia was around 2,657mm in 2020 and 2,599mm in 2021.
In contrast, the average rainfall for 2022 was 2,928mm – an increase of between 10% and 12%.
The average rainfall for Sarawak was 4,181mm in 2020 and 4,028mm in 2021, which was only slightly less than that of 4,038mm in 2022.
There was no drastic increase in the rainfall for Sabah – 2,656mm (2020), 2,837mm (2021) and 2,668mm (2022).
Prof Azizan said as the country is still under the influence of El Nino, the northeast monsoon continues to have cold surges that will bring heavy rains.
“But these cold surges are not as strong, and the frequency of its occurrences too is normally lower compared to when we are under the influence of a neutral (Enso) or La Nina period,” he said.
Enso (El Nino–Southern Oscillation) reflects the changes in winds and sea surface temperatures over the tropical eastern Pacific Ocean, which then impacts the climate of much of the tropics and subtropics.
The warming phase of the sea temperature is known as El Nino and the cooling phase as La Nina.
Prof Azizan said based on the climatological influence of El Nino, most would forecast some flooding from the cold surges within the maximum rainbelt on the coast or just offshore of the east coast, Sabah and Sarawak.