ICMA Activities 1997-1999

ICMA sponsors or cosponsors a number of workshops and meetings. Here is a list of the meetings held during 1997-1999.

Second Workshop on Solar Activity Effects on the Middle Atmosphere

August 18-22, 1997, Charles University, Prague, Czech Republic

organizers: J. Lastovicka, S. Chandra, L. L. Hood

The workshop covered the effects of solar electromagnetic radiation (solar cycle, solar rotation, and other time scales), solar wind (including geomagnetic storms), and high energy particles on the middle atmosphere and to some extent on the troposphere and lower ionosphere. Problems of distinguishing between long-term solar and anthropogenic effects and other long-term changes (e.g. volcanic) were discussed.

International Symposium on Dynamics and Structure of the Mesopause Region (DYSMER)

March 16-20, 1998, Radio Atmospheric Science Center, Kyoto University, Kyoto, Japan.

organizers: D. C. Fritts, G. G. Shepherd, T. Tsuda

The Symposium was devoted to the dynamics and structure of the mesosphere and lower thermosphere, with particular emphasis on the wave propagation, interaction, and instability processes that shape this region. It was primarily organized within the framework of PSMOS (Planetary Scale Mesopause Observing System) of SCOSTEP, and it had joint scientific co-sponsorship by IAMAS/ICMA.

The main topics of the symposium were ground-based radar/optical observations, satellite and rocket measurements, modeling and theory of atmospheric wave and turbulence processes near the mesopause, and the implications of these processes for transport and diffusion. The five full days of the symposium were composed of eight main sessions: (1) Gravity waves and turbulence, (2) Atmospheric tides, (3) Planetary waves, (4) Layered structure, (5) Thermal structure of the mesopause, (6) Neutral wind in the lower thermosphere, (7) Global structure of airglow, and (8) Small scale structure of airglow.

Cooling and Sinking of the Middle and Upper Atmosphere

July 6-10, 1998, Institute of Atmospheric Physics, Moscow, Russia

organizer: G. S. Golitsyn

Recent observations in Russia indicated considerable cooling and sinking of the upper atmosphere during the last decade. The negative trends in temperature, exceeding climatic changes, were detected by rockets and optical observations.

International Workshop of the ICMA Working Group on Layered Phenomena in the Mesopause Region

September 16-18, 1998, Institute of Atmospheric Physics, Kuehlungsborn, Germany

organizers: G. E. Thomas, U. von Zahn, F.-J. Luebken

Subjects at the workshop included lidar measurements of NLC, simultaneous NLC/PMSE measurements, in-situ measurements of dust, in-situ studies of particulate charging, southern hemisphere rocket and radar observations, airglow measurements of mesopause temperature, satellite data and their intercomparisons (UARS, MSX, POAM, GOME, etc.), and modeling activities (in particular of tidal variations and the effects of particulate charging).

Long Term Changes and Trends in the Atmosphere (LT-ACT)

February 16-19, 1999, Indian institute of Tropical Meteorology, Pune, India

organizer: Gufran Beig

his workshop brought together various groups of experimentalists and modelers having a common interest to study the long term variations and trends in the lower, middle and upper atmosphere signaling global change. This workshop focused on the results from the past several decades of observations and future predictions using interactive models. Specific broad topics included (1) Global change of neutral composition, ion chemistry, thermal structure and dynamics, (2) Ground-based, satellite and rocket measurements (EISCAT, IRIS, UARS, HALOE, etc.), (3) Model predictions treating radiation, dynamics and chemistry interactively (4) Trends and variations of gravity wave intensity, winds, emission rates, etc. and role of solar and meteorological activities and (5) Sensitivity of mesopause to various changes.