Innovative solutions for fighting climate change

Dr. Winnie Tang August 10, 2023 09:21

For nearly half a century, global warming has been worsening. After the hottest year on record last year, the World Meteorological Organization (WMO) warned lately that global temperatures could soar to record levels in the next five years, driven by the heat-trapping greenhouse gases and El Niño. The latest United Nations report also shows that the earth is likely to cross the critical threshold of global warming within the next decade. In order to reverse global warming, countries are actively looking for ways, innovative technologies in particular, to cool the planet.

In July last year, an interdisciplinary team of scientists from the Massachusetts Institute of Technology in the United States proposed a "space bubble" scheme to deflect and shield 1.8% of incident solar radiation before it hits the Earth in an attempt to reverse today’s global warming trend. Made from a homogenous substance like molten silicon at the size of Brazil, a "bubble array" would be positioned at the Lagrangian Point between the Earth and the Sun, reflecting various wavelengths of solar radiation through subtle changes in bubble thickness. However, bubble arrays are expensive and need to be further studied.

In March, Denmark spearheaded a carbon dioxide storage programme called the Greensand project, which aims to sequester CO2 in a depleted oil field in the Danish North Sea. The project is located on an abandoned oil field more than 200 km off the coast of Denmark, while CO2 will be pumped into a sandstone reservoir 1,800m below the North Sea. If it successfully passed the test phase, the country can inject up to 8 million tons of CO2 per year by 2030. At current emission levels, Danish subsoil is estimated to be able to store Denmark’s next 500 years of CO2 emissions, helping the country to achieve its goal of carbon neutrality by 2045. However, the technology is not without risks. The potential leaks can have severe consequences such as bringing up pollutants underground or displacing salty groundwater from deep rock layers and salining the groundwater near the earth surface.

As for China, in striving to achieve carbon neutrality before 2060, the mainland has been active in applying energy conservation, circular economy, and scientific and technological innovation, especially the widespread use of green energy technology in the fields of energy, industry, transportation and urban and rural construction in recent years. In addition, the country announced last year to protect, restore and plant 70 billion trees by 2030. In fact, China’s 14th “Five Year Plan” has a stated target of increasing forest coverage to 24.1% by 2025, and forest stock volume up to 19 billion cubic meters.

As for Hong Kong, the government announced the Hong Kong’s Climate Action Plan 2050 as early as 2021, proposing four major carbon reduction strategies, including net-zero electricity generation, energy-saving and green buildings, green transport, and territory-wide waste reduction, but greening seemed to have been missed out.

The European Union's climate monitoring agency says July was on track to be the hottest month on record. The UN secretary general warned that the era of global warming is over and “the era of global boiling has arrived”, hoping that all countries in the world can unite and strive for zero emissions by mid-century. It is hoped that all sectors in Hong Kong can also work together towards the goal of zero emissions.

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Dr. Winnie Tang

Adjunct Professor, Department of Computer Science, Faculty of Engineering; Department of Geography, Faculty of Social Sciences; and Faculty of Architecture, The University of Hong Kong