PETALING JAYA: The weather usually gets colder at this time of the year but temperatures seem to be dropping lower than usual.

Faizal Parish, an expert in biodiversity and the climate, said the sudden change is related to the extreme weather conditions in other parts of the region, as well as in Europe and the United States.

Scientists are saying that the causes are global climate change and a reported drop in activity on the surface of the sun, called the “sleeping sun” phenomenon.

“The scientists are seeing lower sunspot activity now compared to the past 10 years,” explained Faizal, who is director of the Global Environment Centre here.

“There is now less radiation from the sun reaching us but that alone does not cause a drastic drop in temperature.

“It is the cold mass of air coming from Russia and China that is lowering temperatures.”

He said that while this cold air would usually remain in China, it is now coming further south due to a change in the high-altitude wind flows.

Scientists in Europe have warned that the lack of sunspot activity could lead to a new mini ice-age there, similar to one that happened in the 17th century.

Named the Maunder Minimum, it was a period of drastically reduced sunspot activity that occurred bet­ween 1645 and 1715. It also caused London’s River Thames to freeze over.

Faizal also explained that the switch in wind patterns was due to global climate change.

“The impact of climate change is not just global warming. It can lead to extreme weather, such as heatwaves, cold snaps or droughts,” he said.

“Melting sea ice in the Arctic and changing weather patterns are both possible drivers of the new winter weather trends.”

He pointed out that there have been dramatic weather changes in other countries in the region, such as in northern Vietnam where it snowed for the first time in many years, and parts of Thailand were declared disaster zones after the mercury dipped below 5°C last month.

Solar activity is expected to return to normal in the future.