RAZAK AHMAD The Star 11 Jun 17;
PETALING JAYA: Temperature differences between parts of Kuala Lumpur and its neighbouring rural areas have been found to be as high as 10°C and the gap is widening, research has shown.
This is causing heavier rainfall, resulting in more severe flash floods and hotter temperatures in the city and suburbs than surrounding areas. Ironically, the rainfall is heavier in the cities than in rural areas such as Hulu Langat, where the dams are located.
Climate expert Prof Datuk Dr Azizan Abu Samah from Universiti Malaya said this was due to the “urban heat island” effect, where cities get increasingly warmer compared to surrounding rural areas due to rapid development.
“Due to the increased development of Greater Kuala Lumpur, the urban heat island or hot areas are growing,” he said.
The differences in temperatures between urban and rural areas are also widening by 0.4°C per decade.
Apart from getting hotter, the country’s urban areas are also likely to get heavier rainfall as more rain can occur when a bubble of heated air forms over a very warm area.
Citing a 2014 study on the urban heat island effect in the Klang Valley by fellow academic Dr Illyani Ibrahim, Dr Azizan said Petaling Jaya received increasingly more rain between 1983 and 2007 compared to Hulu Langat, located just 22km away.
The increased rainfall in urban areas, Dr Azizan warned, could add to the risk of flash floods in cities.
“This is because much of the rainwater cannot be absorbed into the ground in built-up areas, causing it to remain on the surface, especially where drainage is poor,” he said.
Dr Azizan was commenting on the findings of a World Bank report which found temperature anomalies in Kuala Lumpur, Petaling Jaya, Penang, Johor Baru, Kuantan and Kota Kinabalu growing faster than the global average (see graphic).
The report, titled “Achieving a System of Competitive Cities in Malaysia”, said climate change is expected to worsen the urban heat island effect and cause more heatwaves and heavy rain in urban areas.
Heavy and more frequent precipitation events are expected and will increase the risk and severity of urban flooding and landslides, according to the study, which was released in December 2015 and carried out with the cooperation of the Economic Planning Unit and Khazanah Nasional Bhd.
Parts of the Klang Valley, including Kuala Lumpur, have become notorious for being inundated during heavy downpour in recent months.
In one of the most recent episodes, four roads in Kuala Lumpur – Jalan Bangsar, Jalan Semantan, Jalan Pantai Baharu and Jalan Pudu – were flooded following heavy rain, causing cars to be submerged in water up to their windows.
Other cities, including in Penang, have also been hit by a rising number of flash floods.
On May 27, a downpour which lasted for a few hours submerged the inline baggage area of the Penang International Airport in Bayan Lepas on the island and flooded several low-lying areas on the mainland.
Dr Azizan said green areas in cities should be protected to help reduce the urban heat island effect.
Green lungs and other forested areas help to cool down urban areas and act as a sponge to absorb excess rainfall in the event of heavy storms, reducing the risk of floods, he said.
“Keeping the city green does not mean we should build more golf courses,” he added.
“It means we need to protect the forested areas in our cities due to the forests’ higher leaf index and ability to help reduce temperatures and absorb water.”
He said improving drainage and planning for future flood mitigation projects similar to Kuala Lumpur’s Stormwater Management and Road Tunnel (SMART) could also help.
“When we spent billions of ringgit to build the SMART tunnel, some people said it was a waste of money. But now it’s considered a success.”
He said the focus should be on how to protect other parts of the city, which are also prone to flash floods, especially in light of rapid development.
‘Gazette town and city plans to reduce environmental risk’
The Star 11 Jun 17;
PETALING JAYA: Local plans that spell out the dos and don’ts of how each town and city in the country can be developed need to be gazetted and followed strictly by the state and local authorities, said the Malaysian Institute of Planners.
Its president Ihsan Zainal Mokhtar said this could help reduce the potential harm that development can bring to the environment.
Commenting on a World Bank study that found temperature anomalies in Malaysian cities growing faster than the global average, Ihsan said it was important to have a good local plan and stick to it.
“A local plan not only spells out population density, which areas need road coverage and where to build schools, but also identifies which green areas can’t be touched,” he said.
Controversial proposals to develop green areas that get easily approved despite opposition by residents are an example of what can happen when a local plan is not gazetted.
“If a local plan is drawn up but not gazetted, it results in less control in development.
“If we don’t stick to the local plan, we will leave more room for interest groups to push their agenda in how an area should be developed, rather than public interest,” Ihsan added.
He said while a number of cities and towns had gazetted local plans, Kuala Lumpur and Penang had yet to gazette their local plans, namely the Kuala Lumpur City Plan 2020 and Penang Local Plan 2020.
To reduce the potential risk of flash floods as a result of higher rainfall in urban centres due to rising temperatures, Ihsan said several measures could be taken.
They include increasing the number of detention and retention ponds.
A detention pond is a low-lying area that holds a set amount of floodwater while slowly draining to another location. A retention pond is designed to hold a specific amount of floodwater indefinitely.
Ihsan also said more greenery could be introduced along footpaths.
Another method is to use bioswales, which are long trenches containing vegetation that receive rainwater run-off and work by slowing down water infiltration.
On the World Bank study which found urban sprawl contributing to greenhouse gases and raising temperatures, he said control measures could include allowing higher density only for projects near the city centre.
“Urban sprawl also involves building many highways into the cities which take a lot of the forests, causing temperatures to rise,” he said.
“Cars travelling into urban centres are also a source of urban heat, so one way to tackle the problem is by improving public transport.”
Groups spell out ways to cool down cities
FATIMAH ZAINAL The Star 12 Jun 17;
PETALING JAYA: It’s the little acts like conserving water and saving electricity – even planting a tree – that can help cool the urban heat island effect in the cities, say environment groups.
Malaysian Nature Society president Henry Goh said while authorities should set aside enough land for green lungs in the cities, the public could also do their bit to help maintain such spaces.
“The first thing to inculcate among the public is to share the knowledge why trees are important to mitigate the heat exchange in regards to industrial emissions of heat and pollution.
“The public can also help by practising more care when disposing waste. Adopt the habit of reducing, recycling and reusing waste,” said Goh.
Conserving water, saving electricity and supporting anti-plastic campaign, he said, would also help towards reducing greenhouse gas and heat.
Power Shift Malaysia co-founder Adrian Yeo said even a simple effort such as planting a tree counted.
They were commenting on Sunday Star’s front page report about the urban heat island effect in Kuala Lumpur caused by rapid development.
A study had showed that the city was not only getting much hotter – up to 10 degrees more – than surrounding rural areas but it was also experiencing heavier rainfall, leading to more severe flash floods, and higher temperatures.
EcoKnights president Yasmin Rasyid said property developers could build each home with a rainwater harvesting tank.
“This can retain rain water for outdoor use before all of this rushes into the drains as storm water and floods the lower areas,” she said.
Yasmin said for free green lungs in the city, vertical gardens on rooftops could also be created, functioning as cooling systems for the buildings.
WWF policy and climate change head Lavanya Rama Iyer said urban folks should continue demanding the protection of existing green lungs such as in the recent cases of Bukit Gasing and Taman Tun Dr Ismail.
“All of us should signal to decisionmakers from local governments that greening the city is necessary for national well-being and development should not compromise this,” she said.
Pertubuhan Pelindung Khazanah Alam Malaysia (Peka) president Puan Sri Shariffa Sabrina Syed Aki urged all environmental NGOs to convene a summit to map out a blueprint.
“Deforestation must be stopped immediately. We need to slow down our development. A sustainable plan is needed to look into conservation and preservation.”
