Solar cycle response and long-term trends in the mesospheric metal layers.

ABSTRACT: The meteoric metal layers (Na, Fe, and K)-which form as a result of the ablation of incoming meteors-act as unique tracers for chemical and dynamical processes that occur within the upper mesosphere/lower thermosphere region. In this work, we examine whether these metal layers are sensitive indicators of decadal long-term changes within the upper atmosphere. Output from a whole-atmosphere climate model is used to assess the response of the Na, K, and Fe layers across a 50?year period (1955-2005). At short timescales, the K layer has previously been shown to exhibit a very different seasonal behavior compared to the other metals. Here we show that this unusual behavior is also exhibited at longer timescales (both the ~11?year solar cycle and 50?year periods), where K displays a much more pronounced response to atmospheric temperature changes than either Na or Fe. The contrasting solar cycle behavior of the K and Na layers predicted by the model is confirmed using satellite and lidar observations for the period 2004-2013.

SUBMITTER: Dawkins ECM 

PROVIDER: S-EPMC6680104 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature