A decade-long climatology of terdiurnal tides using TIMED/SABER observations

摘要

abstract_textpIn this paper, we globally characterize the solar terdiurnal tide in the 80-110km region of Earth's atmosphere through analysis of 10years of temperature measurements made by the Sounding of the Atmosphere using Broadband Emission Radiometry instrument on the Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics spacecraft. The Sun-synchronous (migrating) component (TW3), which is longitude-independent and achieves maximum amplitudes of order of 5K (10K) at 90km (110km), not too different than the 7-15K amplitudes that are typical of the migrating diurnal and semidiurnal tides in this region. Significant longitude variability (approximate to 20-25) in terdiurnal temperature amplitudes also exists, which is decomposed into zonal wave number components. The largest of these (TE1, TW4, and TW5) reveal distinct seasonal-latitudinal and height versus latitude patterns and interannual consistency. In addition, it is demonstrated that these particular components vary in ways that suggest that they originate from nonlinear interactions between diurnal and semidiurnal tides, specifically between DE3 and SW2 for TE1, between DW2 and SW2 for TW4, and between DW1 and SW4 for TW5. We also demonstrate that the terdiurnal tides derived here are not influenced to any significant degree by aliasing due to the presence of otherwaves./p/abstract_text