[1] UNIV CAMBRIDGE, DEPT APPL MATH & THEORET PHYS, CAMBRIDGE CB3 9EW, ENGLAND
[2] UNIV CAMBRIDGE, DEPT ENGN, CAMBRIDGE CB3 9EW, ENGLAND
[3] NORTHROP SERV INC, RES TRIANGLE PK, NC 27709 USA
[4] US EPA, ENVIRONM SCI RES LAB, DIV METEOROL & ASSESSMENT, RES TRIANGLE PK, NC 27711 USA