Topography to blame for worsening air pollution
Kathmandu, March 24
Kathmandu Valley’s air pollution is worsening because of its topographical features, according to the Atmosphere Initiative of the International Centre for Integrated Mountain Development.
At a discussion programme organised by the Nepal Forum of Environmental Journalists, senior climatologist and programme Coordinator of the Atmosphere Initiative Arniko K Pandey said, “The mountains surrounding Kathmandu Valley blocks airflow. The increasing temperature lately is causing warm air to rise and cold air to sink in the Valley, and the same warm air then cools and sinks again, causing air pollution to stay locked in.”
Pandey elucidated further that winds blow through the Valley in the afternoon, when pollution emission is moderate, and pool in the Valley in the evenings when pollution emission is high.
“The same air is circulating above the Valley, accumulating pollution over days, weeks, and months,” he added,
“This has resulted into the formation of polluted haze hanging over the Valley.” Besides, polluted air from outside the Valley also accumulates in here, he said.
ICIMOD informed that the Valley’s air quality is also dependent on the air quality in India, Tarai, and even Dhading, where brick kilns produce air pollutants that travel to the Valley.
ICIMOD’s Atmosphere Initiative, which was established in 2013, works in seven major areas in the region.