From carbon sink to carbon emitter: Clearing of forests led to an increase in carbon emissions from land use in Singapore

According to a recent study by National Parks Board (NParks), land in Singapore has become a net emitter of carbon in 2014, a change from two years previous when it was a carbon sink or absorber. The report attributed this to an increase in a significant conversion of land for development since 2012 and the use of new measurement data on the growth rate of tree biomass.

The study was undertaken as part of the Biennial Update Report which Singapore submits to the United Nations Framework Convention on Climate Change as part of its international obligations every two years.

In the most recent report which was submitted in December last year, it was noted that Singapore’s greenhouse gas emissions totalled 50,908.13 gigagram CO2 equivalent (Gg CO2eq). This is slightly higher than the emissions indicated in the previous report submitted in December 2016 where the country’s 2012 emissions totalled 48,094.65 Gg CO2eq.

Looking deeper, a comparison of the two reports indicate that the category of land use, land use-change and forestry in 2012 showed a net removal of -239.25 Gg CO2eq (including N2O) while in 2014, there was a net emission of 62.03 Gg CO2eq.

However, the report did note that the numbers in this particular sector oscillates over the years. It was also highlighted that the net emissions from agriculture and land-use in Singapore are ‘negligible’ when compared to other economic sectors given the country’s small land-size and highly urbanised landscape. Overall, emissions from land use only contributed 0.12% of Singapore’s total emissions in 2014.

The biggest contributor to the country’s greenhouse gas emissions is still fossil fuels, specifically natural gas. About 95% of Singapore’s electricity is still generated using natural gas.

In a Straits Times report, Associate Professor L. Roman Carrasco from the National University of Singapore (NUS) said that there are two ways forests function as climate change mitigators. First, trees take in carbon dioxide from the atmosphere through the process of photosynthesis. Second, forests also prevent carbon from being re-released into the atmosphere by locking those gasses in tree trunks and roots.

“Compared to cutting the forest and planting new trees, keeping mature forests is a much more effective way to prevent climate change,” said the professor.

Deputy director for international biodiversity conservation at NParks Mr Hassan Ibrahim said that Singapore’s vegetated and forest areas – from nature reserves to mangroves – remain as carbon sinks in Singapore.

In an effort to regenerate the country’s secondary forests in nature parks that buffer Bukit Timah and the Central Catchment Nature Researches, NParks introduced the Forest Restoration Action Plan which is a 10-year plan during which native species of flora will be planted to improve soil conditions and attracts dispersers and pollinators. On top of that, invasive weed species will be removed to further help the forest regenerate.