We have extended our 40-year satellite data record of polar mesospheric cloud (PMC) behavior by adding data from a new instrument. Long-term trends in PMC ice water content derived from this record are smaller since 1998 compared to the first part of our data record. The PMC response to solar activity has decreased in the Northern Hemisphere but increased in the Southern Hemisphere, for reasons that are not understood.
We have extended our 40-year satellite data record of polar mesospheric cloud (PMC) behavior by...