DROPPS: A study of the polar summer mesosphere with rocket, radar and lidar

DROPPS (The Distribution and Role of Particles in the Polar Summer Mesosphe re) was a highly coordinated international study conducted in July, 1999 fr om the Norwegian rocket range (Andoya, Norway). Two sequences of rockets we re launched. Each included one NASA DROPPS payload, containing instruments to measure the electrodynamic and optical properties of dust/aerosol layers , accompanied by European payloads (MIDAS, Mini-MIDAS, and/or Mini-DUSTY) t o study the same structures in a complementary manner. Meteorological rocke ts provided winds and temperature. ALOMAR lidars and radars (located adjace nt to the launch site) monitored the mesosphere for noctilucent clouds (NLC s) and polar mesosphere summer echoes (PMSEs), respectively. EISCAT radars provided PMSE and related information at a remote site (Tromso, Norway). Se quence 1 (5-6 July) was launched into a strong PMSE with a weak NLC present ; sequence 2 (14 July) occurred during a strong NLC with no PMSE evident. H ere we describe program details along with preliminary results.