LONG-TERM TRENDS IN THE MESOSPHERE AND LOWER THERMOSPHERE
Authors: Institute of Atmospheric Physics CAS, Prague, Czech Republic; email@example.com
Long-distance propagation of infrasound is realized through the stratospheric and lower thermospheric reflections, thus it depends on background conditions in these two regions. However, contemporary climate change and other long-term change scan change these background conditions. Here I give you, as co-chairman of IAGA/ICMA trend WG and SCOSTEP/VarSITI/ROSMIC trend WG brief overview of trends in the mesosphere and lower thermosphere. These trends are substantially stronger than those in the troposphere. The primary driver is the increasing atmospheric concentration of carbon dioxide but some role is played also by ozone, water vapor, solar and geomagnetic activity. As a consequence of that, trends need not be stable and they can change with time even to opposite trends.