US and Chinese scientists have developed a novel computer model that can help in accurately predicting air pollution levels in a region. Moreover, this model can predict air pollution levels a season in advance. The statistical model, described in the journal Science Advances, uses certain climatic patterns related to the ocean that have a regulatory effect on the wintertime air pollution over northern India. India that is among the world's most polluted countries with particulate matter (PM) 2.5 levels spiking over 500 microgrammes per cubic metre in Delhi and multiple other north Indian states in the previous year.
The study found that the inter-annual variability of wintertime aerosol pollution over the northern part of India is regulated mainly by El Nino, which is a climate cycle in the Pacific Ocean with a global impact on weather patterns. Moreover, the Antarctic Oscillation (AAO), a low-frequency mode of atmospheric variability of the southern hemisphere also had a key role. Both El Nino sea surface temperature (SST) anomalies and AAO-induced anomalies can persist from autumn to winter, offering prospects for a pre-winter forecast of wintertime aerosol pollution over northern India, researchers wrote in the research paper.
According to the State of Global Air 2019 report published earlier this year, over 1.2 million people died in India due to air pollution in 2017. In such a case, the new computer model could allow the government to predict aerosol pollution conditions in winter and accordingly improve plans for pollution control, researchers said. Meng Gao from School of Engineering and Applied Sciences, Harvard University in the US said that they have built a statistical prediction model, which uses two autumn temperature variation patterns as predictors. With it, we will know air pollution in winter. In autumn, we have these indices calculated based on sea surface temperature and geopotential height fields, then the built model will tell you if the wintertime air pollution is severe or not.
Gao further added that there is no such study for India that tells you what will happen for India as much as a season in advance. This study also tells you the dominant climate factor for Indian air pollution, which has not been done before. The researchers, including those from Fudan University and Nanjing University of Information Science and Technology in China constructed a multivariable regression model incorporating El Nino and AAO indices for autumn to predict wintertime AOD. The prediction exhibits a high degree of consistency with observation, they noted.