How air pressure change in Arctic is causing fog in Delhi

How air pressure change in Arctic is causing fog in Delhi

News

A new study of the Indian Institute of Tropical Meteorology (IITM), Pune, has found that widespread fog conditions over the Indo-Gangetic plains were connected to the abnormal movement of high pressure systems over the Arctic Circle and the Eurasian middle latitudes.

Important facts

1. The study is based on analysis of 105 cases of fog events in the period between 1979 and 2013. The study period for the research was December and January months
2. Mechanism:

• When an environment with lower air pressure surrounds the Arctic region, the cold air stays locked-up within the Arctic Circle
• The development of high air pressure over the Arctic Circle, combined with east-west movements of air circulation over Eurasia cause more cold air to advance towards the tropical latitudes and the Indo-Gangetic Plains
• It then allows development of high pressure and favours fog formation in the Indo-Gangetic Plains