Premium
Mesospheric gravity waves over a tropical convective region observed by OH airglow imaging in Indonesia
Author(s) -
Nakamura T.,
Aono T.,
Tsuda T.,
Admiranto A. G.,
Achmad E.
Publication year - 2003
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2003gl017619
Subject(s) - airglow , gravity wave , thermosphere , mesosphere , geology , infragravity wave , troposphere , atmospheric sciences , atmosphere (unit) , convection , wavelength , gravitational wave , geophysics , wave propagation , ionosphere , physics , stratosphere , meteorology , longitudinal wave , mechanical wave , astronomy , optoelectronics , quantum mechanics
From OH airglow imaging observation carried out over one year in Indonesia, 74 events of gravity waves in the MLT (Mesosphere and Lower Thermosphere) region were extracted. Observed period, horizontal wavelength and observed horizontal phase speeds of gravity waves were typically 5–13 min, 13–45 km and 37–75 m/s, respectively. Propagation directions were mostly southward except for the period between December and February, when eastward propagation was preferential. Spatial distributions of tropospheric clouds, estimated with GMS (Geostationary Meteorological Satellite) were consistent with the propagation direction of gravity waves, i.e., these clouds mainly existed in the opposite direction to the propagation direction of waves. This suggests that horizontal propagation characteristics of the short period gravity waves in the low latitude MLT region are mainly affected by the distribution of the wave sources in the troposphere, and the effect of the background mean wind in the middle atmosphere is smaller, as it is weaker (∼20 m/s) in the equatorial region.