14:45 〜 15:00
[PEM11-17] Pattern matching of polar mesospheric clouds with data from the meteorological satellite Himawari-8
キーワード:極中間巻雲、ひまわり8号
A cloud tracking technique is applied to polar mesospheric cloud (PMC) data from the Geostationary-Earth-Orbit (GEO) meteorological satellite Himawari-8 to examine the horizontal movement of PMCs. While previous PMC observations from the ground and Low-Earth-Orbit (LEO) satellites have a limitation on local time coverage, observations from the GEO satellite provide a great opportunity to study the PMC variability with all local time coverage and a wide field of view. The band 1 (the blue band, 0.47μm) data of the Advanced Himawari Imager (AHI) onboard Himawari-8 is resampled to the horizontal versus vertical grids data on the Earth-s limb. A pattern matching technique is applied to the PMC peak radiance of the resampling data, and the horizontal movement of PMC along the transverse direction to the line of sight is derived. The tracking velocity approximates the zonal movement of PMCs around the latitude of 81.3ºN and the longitude of 140.7ºE. The horizontal movement shows a large oscillation with an amplitude of order 10–30 m/s and the spectral peaks at periods of 12, 14.76, and 24 hours. The mean velocity for the northern summer season of 2018 is about 7 m/s in the westward direction. The westerly mean movement is consistent with the horizontal wind derived from PMC images taken with the Cloud Imaging and Particle Size instrument (CIPS) on the Aeronomy of Ice in the Mesosphere (AIM) satellite, and the wind of HWM14. The horizontal movement of PMC observed by Himawari-8 is likely to be subjected to wind advection.