Determination of Global Mean Eddy Diffusive Transport in the Mesosphere and Lower Thermosphere From Atomic Oxygen and Carbon Dioxide Climatologies

2019 ◽  
Vol 124 (23) ◽  
pp. 13519-13533
Author(s):  
G. R. Swenson ◽  
C. C. J. H. Salinas ◽  
F. Vargas ◽  
Y. Zhu ◽  
M. Kaufmann ◽  
...  
2021 ◽  
Author(s):  
Martin Wienold ◽  
Alexey Semenov ◽  
Heiko Richter ◽  
Heinz-Wilhelm Hübers

<p>The Oxygen Spectrometer for Atmospheric Science on a Balloon (OSAS-B) is dedicated to the remote sounding of atomic oxygen in the mesosphere and lower thermosphere (MLT) region of Earth's atmosphere, where atomic oxygen is the dominant species. Quantitative radiometry of atomic oxygen via its visible and near-infrared transitions has been difficult, due to the complex excitation physics involved. OSAS-B is a heterodyne spectrometer for the thermally excited ground state transition of atomic oxygen at 4.75 THz. It will enable spectrally resolved measurements of the line shape,  which in turn enables the determination of the concentration of atomic oxygen in the MLT. Due to water absorption, this line can only be observed from high-altitude platforms such as a high-flying airplanes, balloons or satellites. Recently the first spectrally resolved observation of the 4.75-THz line has been reported using a heterodyne spectrometer on SOFIA, the Stratospheric Observatory for Infrared Astronomy [1]. Compared to SOFIA a balloon-borne instrument has the advantage of not being hampered by atmospheric water vapor absorption. OSAS-B will comprise a hot-electron bolometer mixer and a quantum-cascade laser as local oscillator in a combined helium/nitrogen dewar. A turning mirror will allow for sounding at different vertical inclinations. The  first flight of OSAS-B is planned for autumn 2022 in the frame of the European HEMERA project [2].</p><p>[1] H. Richter et al., Direct measurements of atomic oxygen in the mesosphere and lower thermosphere using terahertz heterodyne spectroscopy, accepted for publication in Communications Earth & Environment (2021).</p><p>[2] https://www.hemera-h2020.eu/</p>


1980 ◽  
Vol 85 (A3) ◽  
pp. 1291-1296 ◽  
Author(s):  
L.C. Howlett ◽  
K.D. Baker ◽  
L.R. Megill ◽  
A.W. Shaw ◽  
W.R. Pendleton ◽  
...  

2017 ◽  
Vol 122 (4) ◽  
pp. 4474-4488 ◽  
Author(s):  
Liying Qian ◽  
Alan G. Burns ◽  
Stanley C. Solomon ◽  
Wenbin Wang

2018 ◽  
Vol 11 (1) ◽  
pp. 473-487 ◽  
Author(s):  
Amirmahdi Zarboo ◽  
Stefan Bender ◽  
John P. Burrows ◽  
Johannes Orphal ◽  
Miriam Sinnhuber

Abstract. We present the retrieved volume emission rates (VERs) from the airglow of both the daytime and twilight O2(1Σ) band and O2(1Δ) band emissions in the mesosphere and lower thermosphere (MLT). The SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) onboard the European Space Agency Envisat satellite observes upwelling radiances in limb-viewing geometry during its special MLT mode over the range 50–150 km. In this study we use the limb observations in the visible (595–811 nm) and near-infrared (1200–1360 nm) bands. We have investigated the daily mean latitudinal distributions and the time series of the retrieved VER in the altitude range from 53 to 149 km. The maximal observed VERs of O2(1Δ) during daytime are typically 1 to 2 orders of magnitude larger than those of O2(1Σ). The latter peaks at around 90 km, whereas the O2(1Δ) emissivity decreases with altitude, with the largest values at the lower edge of the observations (about 53 km). The VER values in the upper mesosphere (above 80 km) are found to depend on the position of the sun, with pronounced high values occurring during summer for O2(1Δ). O2(1Σ) emissions show additional high values at polar latitudes during winter and spring. These additional high values are presumably related to the downwelling of atomic oxygen after large sudden stratospheric warmings (SSWs). Accurate measurements of the O2(1Σ) and O2(1Δ) airglow, provided that the mechanism of their production is understood, yield valuable information about both the chemistry and dynamics in the MLT. For example, they can be used to infer the amounts and distribution of ozone, solar heating rates, and temperature in the MLT.


2004 ◽  
Vol 22 (10) ◽  
pp. 3395-3410 ◽  
Author(s):  
Y. I. Portnyagin ◽  
T. V. Solovjova ◽  
N. A. Makarov ◽  
E. G. Merzlyakov ◽  
A. H. Manson ◽  
...  

Abstract. The Arctic MLT wind regime parameters measured at the ground-based network of MF and meteor radar stations (Andenes 69° N, Tromsø 70° N, Esrange 68° N, Dixon 73.5° N, Poker Flat 65° N and Resolute Bay 75° N) are discussed and compared with those observed in the mid-latitudes. The network of the ground-based MF and meteor radars for measuring winds in the Arctic upper mesosphere and lower thermosphere provides an excellent opportunity for study of the main global dynamical structures in this height region and their dependence from longitude. Preliminary estimates of the differences between the measured winds and tides from the different radar types, situated 125-273km apart (Tromsø, Andenes and Esrange), are provided. Despite some differences arising from using different types of radars it is possible to study the dynamical wind structures. It is revealed that most of the observed dynamical structures are persistent from year to year, thus permitting the analysis of the Arctic MLT dynamics in a climatological sense. The seasonal behaviour of the zonally averaged wind parameters is, to some extent, similar to that observed at the moderate latitudes. However, the strength of the winds (except the prevailing meridional wind and the diurnal tide amplitudes) in the Arctic MLT region is, in general, less than that detected at the moderate latitudes, decreasing toward the pole. There are also some features in the vertical structure and seasonal variations of the Arctic MLT winds which are different from the expectations of the well-known empirical wind models CIRA-86 and HWM-93. The tidal phases show a very definite longitudinal dependence that permits the determination of the corresponding zonal wave numbers. It is shown that the migrating tides play an important role in the dynamics of the Arctic MLT region. However, there are clear indications with the presence in some months of non-migrating tidal modes of significant appreciable amplitude.


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