It showed that the amount of methane gas in Dhaka’s atmosphere increased by 21.1 ppb (parts per billion) during that time period. It was 22.5 ppb in Karachi over the same time period.
Speaking to Prothom Allo, James J Shaver, head of the research team and professor of chemistry at the University of Wisconsin-Madison, said, “We have long been referring to agricultural and rural water bodies as a source of methane emissions. However, we identified several other causes of methane emissions in 61 cities, including leaks in gas supply lines, sewage and water mixed with industrial waste. These sources of methane gas are making the air of the city dangerous. Plus, it’s raising the temperature of the world.”