I was feeling puzzled about the extreme floods in many parts of the country. We have always had floods in the East Coast, but why has the flooding been so bad and widespread this time around? To get some answers, I asked Dr Chan Ngai Weng, a professor of physical geography at USM, what he thought were the real causes of the severe floods.
This was Prof Chan’s response:
Kelantan has always been a flood-prone state and Malaysia a flood-prone country. We will never be free from floods in much the same way that Ethiopia will never be free from drought. It is in the nature of our climate.
The current floods, however, appear to be one of the worst in recent decades. Climate change is a likely cause as greater temperature extremes generate greater storms, stronger monsoons and heavier rains.
Yet, we also need to remember that humans have completely changed the face of the earth from natural (water absorbant and retentive) surfaces such as forests to urban (water impermeable and non-absorbant) surfaces (concrete, cement etc). These result in much of the rain flowing on land surfaces as runoff, leading to floods.
Rivers’ drainage capacities are also significantly reduced due to sedimentation. Worst of all, buildings and other structures are erected right on river banks, restricting rivers’ ability to manoeuvre.
In the deltas, sedimentation restricts flow of river water into the seas leading to backlogging of water which floods riverine areas.
Rainforests and wetlands that absorb a huge amount of rain water have been carelessly logged and totally drained for agriculture and other human land uses.
Overall, humans are the ‘real’ cause of the current floods. Even global warming and current climate change is largely caused by humans.
Address the human causes, and Kelantan and other parts of Malaysia will see less flooding of lesser frequencies and magnitudes.
Don’t blame it on God or Nature!
Prof Chan has a Master’s Degree in Climatology & Meteorology from University Malaya and a Doctorate in Environmental Hazards Management from Middlesex University, United Kingdom.