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Hibbins, R. E.

Publications and source records attributed to Hibbins, R. E..

2 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

QBO Modulation of the Mesopause Gravity Wave Momentum Flux over Tierra del Fuego

The interannual variability of the mesosphere and lower thermosphere (MLT) gravity wave momentum flux over southern mid latitudes (53.7degS) has been studied using more than 7 years of meteor radar observations at Ro Grande, Argentina. A modulation, with periods similar to that of the equatorial stratospheric quasi-biennial oscillation (QBO), is observed in the vertical flux of zonal as well as meridional momentum. The QBO signal is largest in the zonal component during summer and is in phase with the stratospheric QBO at 50 hPa (approx. 21 km). The relation between the stratospheric QBO and the QBO modulation in the MLT gravity wave forcing (derived from the divergence of the momentum flux) was found to be consistent with that expected from the Holton-Tan effect coupled to the interhemispheric coupling mechanism. These results provide the first observational support for the existence of the midlatitude gravity wave forcing anomalies as hypothesized in the interhemispheric coupling mechanism.

De Wit, R. J.↗
NASA NTRS1994

Diffuse interstellar bands between 3900 A and 4200 A

Presented here are spectra and data on five probable diffuse bands with central wavelengths near 4180, 4070, 4040, 4000, and 3980 A which have full-width-half-maxima lying in the range 10-30 A. No narrow unidentified diffuse bands were found, but atomic and diatomic molecular absorptions, including CH and CH(sup +), were readily detected along some lines of sight. Although broad diffuse bands have now been found at longer wavelengths that appeared at one time to be the case (Herbig and Leka, 1991), it is clear that there are no prominent narrow bands at the shorter wavelength end of the diffuse band spectrum. This high-resolution spectra was reported for a number of reddened O- and B-typed and comparison stars, recorded with the 88 inch University of Hawaii telesecope in June of 1993. The sample included the heavily reddened star HD 183143.

Hibbins, R. E.↗