Using a combination of satellite observations and computer
modelling, researchers of the Max Planck Institute for Chemistry
have studied nitrogen oxides pollution over the Indian Ocean.
They showed that the central Indian Ocean in the southern
hemisphere is not always as pristine as found earlier during the
winter monsoon period, but is polluted during the monsoon
transition periods by pollution plumes from Africa and Southeast
Asia. Generally, the most polluted region is the Bay of Bengal,
which is influenced by Indian and south-east Asian outflow
during most of the year and China during part of the year
(Geophysical Research Letters, 30 April 2004 and 11 August
2004). Current knowledge of atmospheric chemistry over the
Indian Ocean is still limited due to the scarcity of long-term
observations covering all seasons. The region is dynamically and
chemically active because of the strong tropical sunlight, high
humidity and the increasing anthropogenic emissions. The Indian
Ocean Experiment (INDOEX) was an inte