Singapore could get hotter, wetter from 2070: Climate change study

SIAU MING EN

APRIL 15, 2015

SINGAPORE — The unusually warm temperatures which Singapore encounters occasionally could become the norm from 2070, and the country can also expect more intense and frequent heavy rainfall by then.

These were findings from Phase 1 of the Second National Climate Change Study, which was commissioned by the National Environment Agency (NEA) and the United Kingdom’s Met Office Hadley Centre.



The models projected findings based on two scenarios: one assumes action is taken to control emissions and the other is based on a business-as-usual scenario where fossil fuels continue to be used with no mitigation efforts.

The study projected that between 2070 and 2099, average daily temperatures across Singapore will increase by 1.4 to 2.7°C under the lower emissions scenario to between 28.8 and 30.1°C. Under the business-as-usual scenario, the average daily temperatures will increase by 2.9 to 4.6°C to between 30.3 and 32.0°C.

The mean daily temperature during the baseline period of 1980 to 2009 is 27.4°C.

The number of warm days — defined as above 34.1°C — between February to May is expected to spike from an average of 25 days to 108 days in the lower emissions scenario. All days throughout those months will be warm in a business-as-usual scenario.

The study, which was completed early this year, used high resolution climate models to project regional climate and sea level changes specifically for the region and Singapore for the 21st century, said NEA in a media briefing today (April 15).

Phase 1 of the study used a downscaled and “carefully chosen” sub-set of the global climate projection models used in the Inter-governmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5).

“The findings imply that the unusually warm temperatures Singapore encounters occasionally could become the norm in the future and that days with ‘record’ temperatures above those experienced historically will become more frequent,” said an NEA spokesperson.

For rainfall, projections show an increasing trend, particularly during the wetter season, in the intensity and frequency of heavy rainfall events over Singapore. Rainy seasons are expected to get wetter while dry seasons are expected to get drier in both scenarios.

The study also projected a mean sea level rise of up to 0.6m for the lower emissions scenario, and up to 0.76m rise in the business-as-usual model.

Phase 2 of the study, which started at the end of last year, is making use of the projections from Phase 1 to examine the climate change impact on areas such as water resources and drainage, biodiversity and greenery, network and building infrastructure. Key findings from Phase 2 is expected to by ready by end of this year.