Thunderstorms in the tropics don’t make a news story, but when they seem so relentless, and rage with such an extreme edge, it makes me wonder: Is this really normal? One thunderstorm last month even smashed the glass panel of a building in Kuala Lumpur, raining glass on people inside.
I wonder, too, about flood disasters which we’ve seen almost every year in the last several years. And what about scorching hot days, which seem to be ever more frequent? The weather does feel hotter than a few decades ago. I don’t recall such blistering heat growing up as a child in KL. Back then, I’d sit comfortably in my parents’ car with no air-conditioning, just the breeze from open windows – but there were no traffic jams to melt in then.
There is solid scientific evidence that the earth is hotter – 19 of the warmest years have occurred since 2000. And five of the warmest years have occurred in the last six years, a fact that literally chills me.
What about locally? Are those severe hot spells, deluges and storms just “normal”, or part of a worrying trend caused by climate change? I put these questions to a scientist who has studied climate patterns over decades in Malaysia.
“Indeed, Malaysia has been experiencing a warming trend in the last five decades, ” confirms Prof Dr Fredolin Tangang, a climatologist and chairperson of Universiti Kebangsaan Malaysia’s Earth Sciences and Environment Department.
That’s in line with global trends.
One study Prof Tangang worked on, which looked at temperatures in 32 climate stations in Malaysia from 1985 to 2018, found “strong evidence of warming”, particularly in cities in northern and western Peninsular Malaysia, in comparison with rural and highland areas and Sabah and Sarawak. There was also a drop in the number of cool days and cool nights. Other studies corroborate these rising temperatures.
The increased heat will lead to longer dry spells. “If, let’s say, we have no rain for five days now, in the future it might be 10 days, ” Prof Tangang says.
We’ll also have periods of more rainfall. Warmer temperatures mean more moisture content in the atmosphere (about 7% more for every 1˚C rise in temperature), which leads to more rainfall and more floods. This pattern is not uniform, though.
Since the 1980s, Malaysia has had more days with extreme rainfall and, thus, more floods. This follows a global trend. In 2017, floods left half of Penang under water. More extreme wind events and thunderstorm days have also been reported.
But KL’s wild thunderstorms – which have even included hail – are fairly unique, as the city has had the country’s highest temperature rises. Due to the “urban heat island” effect, cities absorb and retain heat in buildings and artificial surfaces (whereas forests are like natural air-conditioners due to water transpiration). The city’s high temperatures strengthen thunderstorms and increase rainfall, says Prof Tangang. In the last three decades, there has been a 35% increase in extreme rainfall in KL. This trend is likely to continue, he says. That means the thunderstorms will only get worse.
Globally, all kinds of extreme weather events are on the rise: record heatwaves, torrential floods, destructive wildfires, violent storms, devastating droughts and intense hurricanes. Events that were once rare might now occur frequently.
Prof Tangang, who is a former vice-chair of the United Nation’s Intergovernmental Panel on Climate Change (IPCC) Working Group 1, also leads Cordex South-East Asia, which coordinates regional climate modelling under the World Climate Research Programme. (Cordex stands for Coordinated Regional Climate Downscaling Experiment.)
Predicting future climate patterns is complex. It involves considering monsoon seasons and natural phenomena such as El Niño (which causes extreme dryness and high heat, as seen in 2015/2016). Also, the oceans, which store 90% of excess heat and are the “engine” of climate, bring in winds that change weather.
One Cordex study indicated the region’s future climate would change significantly if the world fails to mitigate climate change (and currently we are failing to do that).
The most worrying future change showed by one study is increased drought conditions, similar to those from an extreme El Niño, which is projected to occur annually from June to October over Malaysia and Indonesia, particularly in Sumatra and Kalimantan. Also, climate change may cause El Niño events to be twice as frequent.
Climate-related disasters are set to increase – they have already tripled in the last 30 years, says international aid organisation Oxfam. Globally, last year, the record number of hurricanes, wildfires and floods – all exacerbated by climate change – cost US$210bil (RM862.7bil) in damage, noted a report by reinsurance company Munich Re. Almost a third of the losses were in Asia. And every year, climate change is also forcing over 20 million people from their homes, Oxfam says.
Global warming will impact our water supply, agricultural production and fisheries. Malaysia urgently needs to start preparing for this with climate adaptation, which is in its infancy here.
Must we wait for a disaster before we take action?
Human Writes columnist Mangai Balasegaram writes mostly on health but also delves into anything on being human. She has worked with international public health bodies and has a Masters in public health. Write to her at email@example.com. The views expressed here are entirely the writer's own.