Characteristics of Gravity Waves During the Occurrence of the Small-Scale Strong Convection Observed by MST Radar

Convection is an important source to excite gravity waves. But the activity characteristics of the convection are hard to research, because it is transient and localized. This paper utilizes the five beams operated by mesosphere–stratosphere–troposphere radar to study the radial movements before, during, and after the small-scale convection. The Doppler spectra of radar echoes during the convection are evidently different from that in the clear weather. The strong updrafts (<inline-formula> <tex-math notation="LaTeX">$\sim 5.1\,\,\text {m}\cdot \text {s}^{-1}$ </tex-math></inline-formula>) and downdrafts (<inline-formula> <tex-math notation="LaTeX">$\sim 2.4\,\,\text {m}\cdot \text {s}^{-1}$ </tex-math></inline-formula>) make the turbulent motion compositions more complex, so the radial Doppler velocity and Doppler widths of five beams are almost significantly different at the same height. The characteristics of gravity waves are detected by using the quasi-monochromatic inertia gravity wave model. The results indicate that: 1) the kinetic energies of the IGWs during the convection are more powerful than that before and after the convection, and the propagation directions of the IGWs during the convection are also different to that before and after the convection and 2) the propagation parameters of the IGWs in different regions are also different during the convection, which means that the cold zone is at south and the warm zone is at north for this convection case.

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