R.B. Husar, June 2, 1998, rhusar@mecf.wustl.edu

1. Smoke and dust from 'natural' sources is always present in the atmosphere. Extreme fine particle events like the Central American smoke and the Asian dust can cause regional-scale concentration peaks in excess of 50 mg/m³.
2. The episodic impact of fine particle events can reach several thousand miles from their sources and they tend to cross international boundaries.
3. Operational satellites managed by US and foreign agencies, are uniquely suitable for early identification and tracking of extreme natural or anthropogenic fine particle events. Publicly available web-based satellite data delivery systems are already in place.
4. During major fine particle events, air quality managers need 'just in time scientific support', not just air quality data. In order to aid managerial decision-making and to inform the public, science needs to explain the causes, the status and the likely evolution of the events.
5. During the extreme events, 'just in time' support can be performed using ad hoc and organized communities of scientist and managers. The communication, coordination, and information sharing for the distributed virtual community can be accomplished effectively through the World Wide Web.
6. Using mainly satellite data, a few experienced observers of the daily dust, smoke, and haze pattern can perform the 'aerosol watch' for the entire world and alert the relevant science and management communities for interesting events.