Of Unwanted imports

If one thought China only poses economic and security threats to India, then he may be wrong. A team of scientists from the Indian Institute of Tropical Meteorology (IITM) in Pune has found that winds flowing from east Asian countries, led by China, are high on pollutants and account for nearly 30% pollution in the lower part of the earth’s surface in India during the post-monsoon months of November-December. The transported pollutants consist of gaseous waste which can be extremely harmful to the respiratory system.
On the other hand, pollution in winds flowing from India to China and North America is significantly less, said the research undertaken by IITM team led by Gufran Beig, programme director, System of Air Pollution Forecasting and Research (SAFAR).
The study says that during winter, northeasterly winds bring highly polluted air from China to India. These pollutants were seen to have travelled as far as Rajasthan and Gujarat. The southwesterly winds from the Indian subcontinent to China and beyond did not transport significantly high levels of pollutants. This is because ozone pollution is quite less over the Indian subcontinent because of cloudy conditions and also because pollutants get washed out in rain.
“Intercontinental pollution is an area of great concern for the international community as this long-range transport of pollutants moves from one country to another,” Beig said.
The study also found that winds coming into the subcontinent from the Himalayan region carry pollutants emitted in countries such as China, Nepal, Bhutan and even Indonesia. But since the Himalayan region is clean, cleaner air travels to other countries compared to the air that travels from other countries to India.
The transported pollutants consist of oxides of nitrogen, carbon monoxide, hydro-carbon and ozone (it is toxic greenhouse gas when found close to the earth’s surface).
Beig used 3-D atmospheric chemistry transport model on India’s second largest super computer at IITM to draw these conclusions.
The study also established that nearly 20% to 30% pollution comes from other regions depending on local weather conditions.