CUHK Research: Changing the world

Professor Amos Tai Pui-kuen believes that, with the complexity of Earth’s systems, a more rounded, interdisciplinary and integrated framework is needed to address sustainability issues, and that it is one that also requires the participation of consumers, such as in the alteration of eating habits. The twin issues of climate change and environmental pollution are prompting scientists to look for solutions which might alleviate the pressure on human societies, other species and Earth’s ecosystems. Many have suggested reducing carbon emissions from the use of fossil fuel and by increasing vegetation cover. Professor Amos Tai, Associate Professor of the Earth and Environmental Sciences Programme at CUHK, approaches the problem from a broader perspective, instead finding the answers in how the Earth’s atmosphere and land surfaces interact with each other. Atmosphere to land Professor Tai’s starting point is the pursuit of human health. “Many diseases, such as asthma and cancers, can stem from environmental pollution, and that comes from a variety of human activities such as fossil fuel combustion,” he says. “These pollutants also significantly harm vegetation and crops, which provide the essential nutrients for humans to stay healthy and productive. Climate change often worsens such impacts.” The professor’s research warns that a combination of continued changes in climate and worsening air pollution in many developing countries will have severe consequences for global food security. Early adoption of emissions control strategies, maintains Professor Tai, will not only help alleviate environmental pressures on the global food supply but will also improve human and ecosystem health. “Immediate actions against climate change and air pollution can bring self-multiplying benefits to human individuals, societies, and all other forms of life on Earth.” Land to atmosphere Although the causes of environmental pollution and climate change have been traditionally attributed to energy production from fossil fuels, Professor Tai also considers factors closer to home in addressing these issues. Specifically, he looks at modern agricultural practices, believing that the ozone, nitrogen, and fine particulate matter they produce bear heavily on air pollution and climate change. “In the past decade or so, we can see that agriculture is an important factor behind air pollution and climate change — it’s not just the use of fossil fuels.” He has suggested that excessive use of fertilisers, deforestation for farming purposes, and the farming of animals for meat together account for 30-40% of greenhouse gases and up to 30% of particle pollutants in major agricultural countries, including China, where the increasingly affluent lifestyles of Chinese people over the past four decades have caused a fivefold surge in demand for meat. Professor Tai and his team have developed computer models to simulate the long-term effects on the planet of such drastic meat consumption. “Ours was the first study to quantify the contribution of Chinese dietary changes to national particulate matter pollution.” Finding solutions to this massive challenge forms the other focus of Professor Tai’s research. He and his team believe the answer lies in making subtle changes such as introducing better agricultural production methods, improved dietary habits and forest management. “This of course includes how food producers can reduce carbon and nitrogen emissions through better management of fertiliser, irrigation water and 67