Channel NewsAsia

S'pore Met Service developing more accurate rainfall model

The Meteorological Service Singapore is working on a modelling system that could forecast more accurate information of heavy rainfall across the island. This means being able to predict where it could rain, and how much rainfall that area could experience.

SINGAPORE: The Meteorological Service Singapore is working on a modelling system that could forecast more accurate information of heavy rainfall across the island. This means being able to predict where it could rain, and how much rainfall that area could experience.

The Met Service said such a model could be developed within the next year or two, and give authorities a longer lead time than the current 20 to 30 minutes, to react to potential flooding or other situations.

At the Changi Meteorological Station, which is located near Changi Airport, observers take readings of rainfall, runway visibility, wind speed, temperature and the amount of sunlight hours Singapore receives.

A day-shift typically sees about two staff and one supervisor working about 10 hours, while the night shift goes on for about 14 hours.

The observers code the data and disseminate it to the Met Service's headquarters, located within the airport terminal. The data is collated with other information and then passed on to incoming aircraft, as well as the relevant authorities.

The data is also used to make weather forecasts -- ranging from three hours to three days.

However, experts said even with current technological advances, being in the tropics has its challenges.

Dr Chris Gordon, director of Centre for Climate Research at the Met Service, said: "A lot of the rainfall which is a particular aspect of the weather for Singapore is being produced by thunderstorms.

"Thunderstorms have some particular characteristics -- not only do they produce a lot of rain, but they also appear and disappear relatively quickly compared to other types of weather systems in different parts of the world.

"One of the challenges here is how do you forecast such a system that's going to arrive, do its thing, and then disappear in a very short period of time? The other aspect of it is that they're in a very small scale."

Dr Gordon said the Met Service is looking at adapting the existing United Kingdom unified modelling system by plugging in local and satellite data into the model.

By adapting it, the model can give a finer scale resolution of forecasting thunderstorms.

The Met Service also looks at various satellite data to detect haze and hotspots, but this may be hampered by passing clouds and the lack of real time information as some satellites pass through only twice a day.

The Met Service expects better pictures and updates from next year when a new breed of satellites are activated.

The Met Service is also preparing for emerging hazards that could have an impact on Singapore.

One area it is studying is space weather -- where solar flares may cause a disturbance to the Earth's magnetosphere. Such magnetic storms could affect communications, power and satellites.

Dr Felicia Shaw, the deputy director of the Met Service's Hazard, Risk and Impact Assessment Unit, said: "Even though magnetic storms are thought to impact high latitudes more, understanding the impact on the world is going to benefit Singapore because it could potentially impact us.

"We have many sensors for weather, but we may now need new ones for emerging hazards and also expertise because to analyse, to interpret the information, requires a certain intellectual capability."

Tweet photos, videos and updates on this story to  @channelnewsasia