Moving people forward: Prof Steve Yim

Recent research suggests that it is impossible to limit global warming to 2 degrees Celsius – a target set by nations to avoid the most severe consequences of climate change, such as the irreversible loss of ice sheets, glaciers and permafrost across the world.

Losing these ice features could push the mercury even higher as they help keep the earth cooler by reflecting solar radiation, says Prof Steve Yim, Director of NTU’s Centre for Climate Change and Environmental Health.

“Researchers are unsure what will happen if we move past a tipping point where ice sheets are lost forever,” adds Prof Yim, who is from NTU’s Asian School of the Environment and Lee Kong Chian School of Medicine, and a Principal Investigator at the University’s Earth Observatory of Singapore.

“The impact of rising temperatures on human health arising from this is also not clear. So, there’s an urgent need for us to understand and prepare for it before it’s too late.”

Making sense of the impact of such points of no return is among the biggest challenges that the climate scientist is facing in his interdisciplinary research on integrating atmospheric science, epidemiology and medical insights to better understand the health impact of air pollution and climate change.

Prof Yim coordinates research at the Centre for Climate Change and Environmental Health to understand how climate change in the tropics affects public health through air pollution, water supply and extreme heat.

He also collaborated with medical researchers to analyse how lung cancer could be affected by black carbon, or soot, which is formed from fossil fuels and biomass burning incompletely. They found that increasing black carbon in the atmosphere by 0.1 micrograms per cubic metre was associated with a 12% jump in lung adenocarcinoma worldwide.

As an expert member of the World Health Organisation’s Global Air Pollution and Health Technical Advisory Group, he is striving to encourage governments to regulate black carbon as an air pollutant that should be regularly monitored.

The advisory group provides policy recommendations on air pollution mitigation strategies – and Prof Yim’s appointment to the group since 2021 highlights global recognition for his research and expertise. He has also been named in Stanford University’s Top 2% Scientists list for four consecutive years since 2021.

The article appeared first in NTU's research & innovation magazine Pushing Frontiers (issue #25, August 2025).