Lessons from Malaysia's 'great floods'

'NEW NORMAL': Flood-hit Pengkalan Chepa, near Kota Baru, on Dec 27. Malaysians should prepare to prevent, mitigate and manage "great floods" effectively because recent events and climate science strongly indicate that they are not one-off events, but part of a national, regional and global pattern linked to climate change and extreme weather events. The situation may worsen in future years.


    Jan 21, 2015

    Lessons from Malaysia's 'great floods'

    THE recent floods in Malaysia should be treated as a "new normal" linked to regular weather extremes, and a system should be established to curb the causes and manage disasters effectively.

    The first half of this month saw Malaysians pre-occupied with the big clean-up following the big floods that swamped many states, especially on the east coast.

    It will take some time to get houses, schools, hospitals, offices, roads, drains and railway tracks back into pre-flood shape.

    The cost of doing so is staggering, with the initial figure exceeded by new estimates.

    The total will run into many billions of ringgit. The government will foot the bill for repairing public facilities. There is some government and spirited public help for flood victims' personal losses.

    But the affected people will still bear immense suffering and losses, for example, of business and livelihood income, on top of lost household belongings.

    It is time to learn the lessons and prepare for the future.

    Hopefully, a high-powered coordinating council will deal with all aspects of analysing the causes of the floods and how severe we can expect future floods to be, as well as minimising the causative factors, planning better to mitigate future events, and preparing to manage them more effectively when they inevitably happen again.


    Recent events and climate science strongly indicate that last year's downpour and floods are not one-off events, but part of a national, regional and global pattern linked to climate change and extreme weather events. We can expect the situation to worsen in future years.

    Malaysia has experienced an increase in temperature, consistent with the global-warming trend, according to data in a 2012 paper by Yap Kok Seng, then the head of the Malaysian Meteorological Department (MMD), and his colleagues.

    The global temperature increase has led to changes in weather, including major wind patterns, amount and intensity of precipitation, and increased frequency of severe storms and weather extremes, according to the paper, Malaysia Climate Change Scenarios.

    Malaysia has experienced more extreme weather events over the past decades, as well as an increase in weather extremes, says the paper, backed by graphs and statistics.

    This increase could be associated with the natural variability in the sea-surface temperatures of the equatorial Pacific Ocean (El Nino/La Nina events) and the Indian Ocean (Indian Ocean Dipole).

    For example, the north-eastern monsoon of 2006/2007 and 2007/2008 brought torrential rain and floods to Malaysia, with the former monsoon being the worst recorded over the southern part of the peninsula, especially in Johor, causing the worst floods.

    Other extreme events such as severe thunderstorms, dry periods and haze have become more prevalent in recent years. Due to the complex interaction of the atmosphere, ocean and biosphere, global warming definitely has contributed to these changes, with climate variability and global warming acting in the same direction over the period.

    The paper points out that as the climate changes due to global warming, sea-surface temperatures (SSTs) also continue to increase. Higher SSTs are generally accompanied by increased water vapour in the lower troposphere, thus the moist static energy that fuels convection and thunderstorms is also increased. Most tropical rainfall, as experienced in Malaysia, is from thunderstorm activities.

    According to the MMD analysis, Malaysia has experienced the following changes:

    Since the 1980s, there have been more days of extreme rainfall events.

    The number of days with extreme wind events has also increased at several stations.

    The peninsula, Sabah and Sarawak have seen more annual thunderstorm days.

    The paper indicates that the north-eastern monsoon and the south-western monsoon have become more intense. Annual rainfall data for the period 2000-2009, compared to 1970-1999, shows an increase in rainfall for most parts of the peninsula (except the central part) as well as Sabah and Sarawak, and this occurred in the five-year period of 2005-2009.

    The regions with the biggest increase in rainfall are the north-eastern coast and north-western coastal parts of the peninsula, the central coast of Sarawak and northern Sabah.

    Interestingly, the paper also finds that there are more frequent and intense dry years (the 1975-2005 period, compared to 1951-75), which are only partly due to El Nino events.

    It thus appears that the new weather pattern in Malaysia includes both heavier rainfall and drier spells - even in the same year. This explains the co-existence of no-rainfall months causing water shortages in various states with high-rainfall and flooding months in other states or even the same states.


    The lesson from all this is that we have to pay more attention to increasing extremes and extreme events in the weather, counteract their causes and deal with their effects. In climate-change terms, this means having plans for mitigation, adaptation, and loss and damage.

    While we can do little to alter weather patterns in the short term, we can certainly do a lot to prevent the situation worse from worsening.

    Top on the list is to stop further deforestation. The widespread felling of trees, especially in highland areas, is a major reason why intense rainfall causes so much flooding.

    The natural tree cover breaks the falling rain and allows the gentler drip of water to seep into the ground, providing groundwater to flow into reservoirs.

    When trees are removed, the rain falls heavily onto the ground, removes the soil, and the water plus the soil are swept into streams and rivers, which get clogged with soil and fill up quickly with the high volume of rainwater.

    The damage begins in the upper reaches of the river and is transformed into devastation as the engorged river reaches urban areas, breaches its banks, and the raging waters sweep away houses, cars and everything else in their way.

    After each disaster, promises are made to stop deforestation and disallow highland development. But after a few months and years, the logging and development works begin again, causing even more damage the next time there are heavy rains.

    This time, the situation has become so serious that the public expects firm and effective action from all levels of government and all relevant agencies.

    Besides conserving the forests, there are many other ways to mitigate and adapt better.

    These include the replanting of trees in deforested areas; soil conservation as a strategy and major activity all over the country; the de-silting of rivers and streams; making major improvements to drainage in urban and rural areas; the climate-proofing of buildings, including building schools and houses on stilts or on pillars in flood-prone areas; and protecting coastal areas from storms, winds and high waves, including through conserving and replanting mangroves.

    There is also a whole set of activities for better management of floods and other disasters, including the establishment of permanent evacuation centres; early warning systems; earlier and better systems of evacuation; the stocking and distribution of food, clean water, medicine and other essentials to victims; plans for repair and rehabilitation; and the upfront allocation of financing.

    If we treat the "great floods" not as once-in-20-years or once-in-a-lifetime events, but as part of the "new normal", then the plans for a better ecosystem and for managing the disasters can be made more systematically, and a significant budget for regular financing can also be set aside.

    Let's hope that we learn the lessons of the recent great floods and prepare comprehensively to prevent, mitigate and manage them effectively. We may not be able to achieve "Never the floods again", but we must achieve "Effectively manage the heavy rains and floods that are sure to come".