Northwestern University professor Dirk Brockmann and his research group examine the global impact of the ash plume:

Mobility patterns in places far from Europe -- including the United States, India and southeast Asia -- were significantly affected by the European disruption.

The team compared the entire worldwide air transportation network before and after the 27 major European airports were closed and used complex network theory to compute and list the most affected airports still operating.

Go to the results summary of the ash plume study

Airneth file: Complex network theory in air transport research