Artykuły w czasopismach: „OH meinel band”

1

Fagundes, P. R., D. Gobbi, H. Takahashi i Y. Sahai. "Mesospheric energy loss rates by OH and O2 emissions at 23°S". Annales Geophysicae 15, nr 6 (30.06.1997): 797–804. http://dx.doi.org/10.1007/s00585-997-0797-4.

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Abstract. The nightglow OH(9, 4) and O2 atmospheric (0,1) band emission intensities and their rotational temperatures T(OH) and T(O2), respectively, observed at Cachoeira Paulista (23°S, 45°W), Brazil, during the period from October 1989 to December 1990, have been analyzed to study the nighttime mesospheric energy loss rates through the radiations from the vibrationally excited OH* and electronically excited O2* bands. The total emission rates of the OH Meinel bands, O2 atmospheric (0,0) and O2 infrared atmospheric (1Δg) bands were calculated using reported data for the relative band intensities I(ν'',ν')/I(9,4), IO2A(0,0)/IO2A(0,1) and IO2(1Δg)/IO2A(0,1). It was found that there is a minimum in equivalent energy loss rate by the OH* Meinel bands during December/January (equivalent energy loss rate of 0.39K/day*, where day* means averaged over the night) and maximum in equivalent energy loss rate during September (equivalent energy loss rate of 0.98K/day*). Energy loss rate by the O2* radiation, on the other hand, is weaker than that by the OH* Meinel bands, showing equivalent energy loss rates of 0.12K/day* and 0.22K/day* during January and September, respectively.

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Parihar, N., A. Taori, S. Gurubaran i G. K. Mukherjee. "Simultaneous measurement of OI 557.7 nm, O2 (0, 1) Atmospheric Band and OH (6, 2) Meinel Band nightglow at Kolhapur (17° N), India". Annales Geophysicae 31, nr 2 (7.02.2013): 197–208. http://dx.doi.org/10.5194/angeo-31-197-2013.

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Abstract. Near-simultaneous measurements of OI 557.7 nm, O2 (0, 1) Atmospheric Band and OH (6, 2) Meinel Band nightglow were carried out at Kolhapur (17° N), India during February–March 2007. Atmospheric temperatures around 87 and 94 km were derived from the knowledge of intensity measurements of spectral features OH (6, 2) Meinel Band and O2 Atmospheric Band, respectively. An account of the behaviour of derived temperatures has been presented. The nocturnal behaviour of OH and O2 temperatures is governed by the waves of tidal origin, whereas the signatures of planetary wave-like oscillations is noted in the night-to-night variation of two temperatures. This is probably the first report of planetary waves observed in nightglow temperatures from the Indian subcontinent.

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3

Sheese, P. E., E. J. Llewellyn, R. L. Gattinger i K. Strong. "OH Meinel band nightglow profiles from OSIRIS observations". Journal of Geophysical Research: Atmospheres 119, nr 19 (3.10.2014): 11,417–11,428. http://dx.doi.org/10.1002/2014jd021617.

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von Savigny, C., I. C. McDade, K. U. Eichmann i J. P. Burrows. "On the dependence of the OH* Meinel emission altitude on vibrational level: SCIAMACHY observations and model simulations". Atmospheric Chemistry and Physics Discussions 12, nr 2 (23.02.2012): 5817–49. http://dx.doi.org/10.5194/acpd-12-5817-2012.

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Abstract. Measurements of the OH Meinel emissions in the terrestrial nightglow are one of the standard ground-based techniques to retrieve upper mesospheric temperatures. It is often assumed that the emission peak altitudes are not strongly dependent on the vibrational level, although this assumption is not based on convincing experimental evidence. In this study we use Envisat/SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY) observations in the near-IR spectral range to retrieve vertical volume emission rate profiles of the OH(3-1), OH(6-2) and OH(8-3) Meinel bands in order to investigate, whether systematic differences in emission peak altitudes can be observed between the different OH Meinel bands. The results indicate that the emission peak altitudes are different for the different vibrational levels, with bands originating from higher vibrational levels having higher emission peak altitudes. It is shown that this finding is consistent with the majority of the previously published results. The SCIAMACHY observations yield differences in emission peak altitudes of up to about 4 km between the OH(3-1) and the OH(8-3) band. The observations are complemented by model simulations of the fractional population of the different vibrational levels and of the vibrational level dependence of the emission peak altitude. The model simulations well reproduce the observed vibrational level dependence of the emission peak altitude – both qualitatively and quantitatively – if quenching by atomic oxygen as well as multi-quantum collisional relaxation by O2 is considered. If a linear relationship between emission peak altitude and vibrational level is assumed, then a peak altitude difference of roughly 0.5 km per vibrational level is inferred from both the SCIAMACHY observations and the model simulations.

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von Savigny, C., I. C. McDade, K. U. Eichmann i J. P. Burrows. "On the dependence of the OH* Meinel emission altitude on vibrational level: SCIAMACHY observations and model simulations". Atmospheric Chemistry and Physics 12, nr 18 (28.09.2012): 8813–28. http://dx.doi.org/10.5194/acp-12-8813-2012.

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Abstract. Measurements of the OH Meinel emissions in the terrestrial nightglow are one of the standard ground-based techniques to retrieve upper mesospheric temperatures. It is often assumed that the emission peak altitudes are not strongly dependent on the vibrational level, although this assumption is not based on convincing experimental evidence. In this study we use Envisat/SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY) observations in the near-IR spectral range to retrieve vertical volume emission rate profiles of the OH(3-1), OH(6-2) and OH(8-3) Meinel bands in order to investigate whether systematic differences in emission peak altitudes can be observed between the different OH Meinel bands. The results indicate that the emission peak altitudes are different for the different vibrational levels, with bands originating from higher vibrational levels having higher emission peak altitudes. It is shown that this finding is consistent with the majority of the previously published results. The SCIAMACHY observations yield differences in emission peak altitudes of up to about 4 km between the OH(3-1) and the OH(8-3) band. The observations are complemented by model simulations of the fractional population of the different vibrational levels and of the vibrational level dependence of the emission peak altitude. The model simulations reproduce the observed vibrational level dependence of the emission peak altitude well – both qualitatively and quantitatively – if quenching by atomic oxygen as well as multi-quantum collisional relaxation by O2 is considered. If a linear relationship between emission peak altitude and vibrational level is assumed, then a peak altitude difference of roughly 0.5 km per vibrational level is inferred from both the SCIAMACHY observations and the model simulations.

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6

Parihar, Navin, Dupinder Singh i Subramanian Gurubaran. "A comparison of ground-based hydroxyl airglow temperatures with SABER/TIMED measurements over 23° N, India". Annales Geophysicae 35, nr 3 (7.03.2017): 353–63. http://dx.doi.org/10.5194/angeo-35-353-2017.

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Abstract. Ground-based observations of OH (6, 2) Meinel band nightglow were carried out at Ranchi (23.3° N, 85.3° E), India, during January–March 2011, December 2011–May 2012 and December 2012–March 2013 using an all-sky imaging system. Near the mesopause, OH temperatures were derived from the OH (6, 2) Meinel band intensity information. A limited comparison of OH temperatures (TOH) with SABER/TIMED measurements in 30 cases was performed by defining almost coincident criterion of ±1.5° latitude–longitude and ±3 min of the ground-based observations. Using SABER OH 1.6 and 2.0 µm volume emission rate profiles as the weighing function, two sets of OH-equivalent temperature (T1. 6 and T2. 0 respectively) were estimated from its kinetic temperature profile for comparison with OH nightglow measurements. Overall, fair agreement existed between ground-based and SABER measurements in the majority of events within the limits of experimental errors. Overall, the mean value of OH-derived temperatures and SABER OH-equivalent temperatures were 197.3 ± 4.6, 192.0 ± 10.8 and 192.7 ± 10.3 K, and the ground-based temperatures were 4–5 K warmer than SABER values. A difference of 8 K or more is noted between two measurements when the peak of the OH emission layer lies in the vicinity of large temperature inversions. A comparison of OH temperatures derived using different sets of Einstein transition probabilities and SABER measurements was also performed; however, OH temperatures derived using Langhoff et al. (1986) transition probabilities were found to compare well.

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Kalogerakis, Konstantinos S. "A previously unrecognized source of the O2Atmospheric band emission in Earth’s nightglow". Science Advances 5, nr 3 (marzec 2019): eaau9255. http://dx.doi.org/10.1126/sciadv.aau9255.

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Earth’s night sky continuously produces a faint chemiluminescence known as nightglow. Two prominent nighttime emissions around 90 km are the O2Atmospheric and the OH Meinel band systems. Despite a plethora of studies since their identification seven decades ago, substantial gaps persist in our understanding of the mechanisms that control them. This report shows that oxygen atoms connect these two emissions: Fast, multiquantum, vibrational-to-electronic relaxation of OH(v) by O atoms activates a pathway that generates O2Atmospheric band emission. This newly discovered source exhibits a strong altitude dependence and can contribute a majority of the observed O2Atmospheric band emission when the peaks of the OH and O-atom layers overlap. The new findings call for a reinterpretation of Earth’s nightglow emissions and a revision of relevant atmospheric models.

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8

Murtagh, D. P., J. Stegman, G. Witt, E. J. Llewellyn i I. C. McDade. "A twilight measurement of the OH(8-3) meinel band and atmospheric temperature". Planetary and Space Science 35, nr 9 (wrzesień 1987): 1149–55. http://dx.doi.org/10.1016/0032-0633(87)90021-3.

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9

McDade, I. C., i E. J. Llewellyn. "Mesospheric oxygen atom densities inferred from night-time OH Meinel band emission rates". Planetary and Space Science 36, nr 9 (wrzesień 1988): 897–905. http://dx.doi.org/10.1016/0032-0633(88)90097-9.

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Parihar, N., S. Gurubaran i G. K. Mukherjee. "Observations of OI 557.7 nm nightglow at Kolhapur (17° N), India". Annales Geophysicae 29, nr 10 (25.10.2011): 1873–84. http://dx.doi.org/10.5194/angeo-29-1873-2011.

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Abstract. Ground-based nightglow observations of the atomic oxygen green line at 557.7 nm have been carried out at a low latitude station Kolhapur (17° N), India, during November 2003–April 2004 and December 2004–May 2005. The nocturnal behaviour of OI 557.7 nm intensity and a comparative study with simultaneous OH Meinel band temperature measurements has been presented. OI 557.7 nm intensity and OH temperature variations covary on many occasions. It was found that an 8 h tide characterizes the variation of intensity and temperature on most nights, and especially during the month of January. This is the first report of prolonged measurements of OI 557.7 nm emission from India.

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GARCIAMUNOZ, A., J. MCCONNELL, I. MCDADE i S. MELO. "Airglow on Mars: Some model expectations for the OH Meinel bands and the O IR atmospheric band". Icarus 176, nr 1 (lipiec 2005): 75–95. http://dx.doi.org/10.1016/j.icarus.2005.01.006.

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Taori, A., A. Guharay i M. J. Taylor. "On the use of simultaneous measurements of OH and O2 emissions to investigate wave growth and dissipation". Annales Geophysicae 25, nr 3 (29.03.2007): 639–43. http://dx.doi.org/10.5194/angeo-25-639-2007.

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Abstract. Simultaneous measurements of mesospheric OH (6–2) Meinel and O2 (0–1) Atmospheric band emissions from a low-latitude station, Maui, Hawaii (20.8° N, 156.2° W) are utilized to study the wave characteristics and associated processes. Deduced temperatures show large variability in both OH and O2 data. The seasonal variability in the temperature shows a well-defined, semiannual type of oscillation, which are comparable to the ground-based rocket sounding data. The "Wave Growth Factor", a ratio of normalized perturbation amplitude in O2 to the OH temperature variability, is estimated for principal as well as residual smaller period components of the nocturnal variability. It is noticed that smaller period waves (less than 12 h) occasionally have large growth factors of about 3–4 during equinox transitions, an indication of wave amplitude amplification within the 87–94 km altitudes while a strong wave-dissipation occurs throughout the year.

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13

López-González, M. J., E. Rodríguez, R. H. Wiens, G. G. Shepherd, S. Sargoytchev, S. Brown, M. G. Shepherd i in. "Seasonal variations of O2 atmospheric and OH(6−2) airglowand temperature at mid-latitudes from SATI observations". Annales Geophysicae 22, nr 3 (19.03.2004): 819–28. http://dx.doi.org/10.5194/angeo-22-819-2004.

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Abstract. More than 3 years of airglow observations with a Spectral Airglow Temperature Imager (SATI) installed at the Sierra Nevada Observatory (37.06°N, 3.38°W) at 2900m height have been analyzed. Values of the column emission rate and vertically averaged temperature of the O2 atmospheric (0–1) band and of the OH Meinel (6–2) band from 1998 to 2002 have been presented. From these observations a clear seasonal variation of both emission rates and rotational temperatures is inferred at this latitude. It is found that the annual variation of the temperatures is larger than the semi-annual variation, while for the emission rates the amplitudes are comparable. Key words. Atmospheric composition and structure (airglow and aurora; pressure density and temperature; instruments and techniques)

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14

Mulligan, F. J., i J. M. Galligan. "Mesopause temperatures calculated from the O2(a1Δg) twilight airglow emission recorded at Maynooth (53.2°N, 6.4°W)". Annales Geophysicae 13, nr 5 (31.05.1995): 558–66. http://dx.doi.org/10.1007/s00585-995-0558-1.

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Abstract. Spectra of the O2(a1Δg) airglow emission band at 1.27 µm have been recorded during twilight at Maynooth (53.2°N, 6.4°W) using a Fourier transform spectrometer. Synthetic spectra have been generated for comparison with the recorded data by assuming a particular temperature at the emitting altitude, and modelling the absorption of each line in the band as it propagates downward through the atmosphere. The temperature used in generating the synthetic spectra was varied until an optimum fit was obtained between the recorded and synthetic data; this temperature was then attributed to the altitude of the emitting layer. Temperatures derived using this technique for 91 twilight periods over an 18-month period exhibit a strong seasonal behaviour with a maximum in winter and minimum in summer. Results from this study are compared with temperatures calculated from the OH(3, 1) Meinel band recorded simultaneously. In winter OH temperatures exceed O2 values by about 10 K, whereas the opposite situation pertains in summer; this result is interpreted in terms of a possible change in the altitude of the mesopause as a function of season. Estimates of the twilight O2(0, 0) total band intensity indicate that its intensity is lower and that its decay is more rapid in summer than in winter, in agreement with earlier observations.

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Mukherjee, G. K., i N. Parihar. "Measurement of rotational temperature at Kolhapur, India". Annales Geophysicae 22, nr 9 (23.09.2004): 3315–21. http://dx.doi.org/10.5194/angeo-22-3315-2004.

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Abstract. Measurements of the hydroxyl rotational temperature for the (8,3) Meinel band have been reported from the observations of the ratio of the relative intensities of P1(2) and P1(4) lines of the OH(8,3) band at Kolhapur (16.8° N, 74.2° E, dip lat. 10.6° N) in India during the period 1 November 2002-29 April 2003 using tilting-filter photometers. Mean values of rotational temperature have been computed for 60 nights. The monthly mean value of temperature lies in the range 194(±11)-208(±18)K. The mean rotational temperature obtained from all the measurements was found to be 202±15K. The results agree with other low-latitude measurements of rotational temperature using photometric airglow techniques. Quasi-periodic fluctuations with a period of about one to two hours have been prominent on many nights. Furthermore, the results show the general agreement between observations and model (MSIS-86) predictions.

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Taylor, M. J., L. C. Gardner i W. R. Pendleton. "Long-period wave signatures in mesospheric OH Meinel (6,2) band intensity and rotational temperature at mid-latitudes". Advances in Space Research 27, nr 6-7 (styczeń 2001): 1171–79. http://dx.doi.org/10.1016/s0273-1177(01)00153-3.

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Franzen, Christoph, Robert Edward Hibbins, Patrick Joseph Espy i Anlaug Amanda Djupvik. "Optimizing hydroxyl airglow retrievals from long-slit astronomical spectroscopic observations". Atmospheric Measurement Techniques 10, nr 8 (25.08.2017): 3093–101. http://dx.doi.org/10.5194/amt-10-3093-2017.

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Abstract. Astronomical spectroscopic observations from ground-based telescopes contain background emission lines from the terrestrial atmosphere's airglow. In the near infrared, this background is composed mainly of emission from Meinel bands of hydroxyl (OH), which is produced in highly excited vibrational states by reduction of ozone near 90 km. This emission contains a wealth of information on the chemical and dynamical state of the Earth's atmosphere. However, observation strategies and data reduction processes are usually optimized to minimize the influence of these features on the astronomical spectrum. Here we discuss a measurement technique to optimize the extraction of the OH airglow signal itself from routine J-, H-, and K-band long-slit astronomical spectroscopic observations. As an example, we use data recorded from a point-source observation by the Nordic Optical Telescope's intermediate-resolution spectrograph, which has a spatial resolution of approximately 100 m at the airglow layer. Emission spectra from the OH vibrational manifold from v′ = 9 down to v′ = 3, with signal-to-noise ratios up to 280, have been extracted from 10.8 s integrations. Rotational temperatures representative of the background atmospheric temperature near 90 km, the mesosphere and lower thermosphere region, can be fitted to the OH rotational lines with an accuracy of around 0.7 K. Using this measurement and analysis technique, we derive a rotational temperature distribution with v′ that agrees with atmospheric model conditions and the preponderance of previous work. We discuss the derived rotational temperatures from the different vibrational bands and highlight the potential for both the archived and future observations, which are at unprecedented spatial and temporal resolutions, to contribute toward the resolution of long-standing problems in atmospheric physics.

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López-González, M. J., E. Rodríguez, G. G. Shepherd, S. Sargoytchev, M. G. Shepherd, V. M. Aushev, S. Brown, M. García-Comas i R. H. Wiens. "Tidal variations of O2 Atmospheric and OH(6-2) airglow and temperature at mid-latitudes from SATI observations". Annales Geophysicae 23, nr 12 (23.12.2005): 3579–90. http://dx.doi.org/10.5194/angeo-23-3579-2005.

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Abstract. Airglow observations with a Spectral Airglow Temperature Imager (SATI), installed at the Sierra Nevada Observatory (37.06° N, 3.38° W) at 2900-m height, have been used to investigate the presence of tidal variations at mid-latitudes in the mesosphere/lower thermosphere region. Diurnal variations of the column emission rate and vertically averaged temperature of the O2 Atmospheric (0-1) band and of the OH Meinel (6-2) band from 5 years (1998-2003) of observations have been analysed. From these observations a clear tidal variation of both emission rates and rotational temperatures is inferred. It is found that the amplitude of the daily variation for both emission rates and temperatures is greater from late autumn to spring than during summer. The amplitude decreases by more than a factor of two during summer and early autumn with respect to the amplitude in the winter-spring months. Although the tidal modulations are preferentially semidiurnal in both rotational temperatures and emission rates during the whole year, during early spring the tidal modulations seem to be more consistent with a diurnal modulation in both rotational temperatures and emission rates. Moreover, the OH emission rate from late autumn to early winter has a pattern suggesting both diurnal and semidiurnal tidal modulations.

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Cosby, P. C., i T. G. Slanger. "OH spectroscopy and chemistry investigated with astronomical sky spectra". Canadian Journal of Physics 85, nr 2 (1.02.2007): 77–99. http://dx.doi.org/10.1139/p06-088.

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This study summarizes the use of a large catalog of astronomical sky spectra to study different aspects of OH spectroscopy and chemistry in the terrestrial night sky. The sky spectra are unique in that they have high spectral resolution, cover the entire visible wavelength region in one exposure, and are intensity-calibrated with respect to standard stars. The intensity calibration, in particular, allows a significant revision to the OH Meinel band intensity distribution that has been in use for 43~years and permits critical evaluation of the many available sets of OH emission coefficients. The spectra further allow the OH rovibrational population distributions to be monitored throughout many nights. The OH vibrational population distribution is found to change during the night, with the population ratio between the extreme high-v and low-v levels that we can detect, v = 9 and v = 3, varying by as much as a factor of two; the low-v levels being predominant earlier in the night. It has been common to determine the kinetic temperature of the OH emission region by assuming that it is equal to the low-J rotational temperature associated with particular OH bands, typically bands originating in the v = 6 and v = 8 levels. The present calibrated data set reveals that the rotational temperatures are significantly greater for high-v than for low-v levels, the typical difference between v = 3 and v = 8 being 15 K. Previous attempts to establish that a difference existed are consistent with our current observations, although conclusions from those earlier results were limited by relatively wide error limits. The present rovibrational population measurements, which extend to high rotational levels (J′ ≤ 25.5), also reveal that the high-J populations are largely independent of vibrational level — the high-J population in v = 3 is similar to that in v = 7.PACS Nos.: 92.60.H, 92.60.hw, 33.20.–t, 33.20.Kf, 33.70.–w

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Parihar, N., i A. Taori. "An investigation of long-distance propagation of gravity waves under CAWSES India Phase II Programme". Annales Geophysicae 33, nr 5 (18.05.2015): 547–60. http://dx.doi.org/10.5194/angeo-33-547-2015.

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Abstract. Coordinated measurements of airglow features from the mesosphere–lower thermosphere (MLT) region were performed at Allahabad (25.5° N, 81.9° E) and Gadanki (13.5° N, 79.2° E), India to study the propagation of gravity waves in 13–27° N latitude range during the period June 2009 to May 2010 under CAWSES (Climate And Weather of Sun Earth System) India Phase II Programme. At Allahabad, imaging observations of OH broadband emissions and OI 557.7 nm emission were made using an all-sky imager, while at Gadanki photometric measurements of OH (6, 2) Meinel band and O2 (0, 1) Atmospheric band emissions were carried out. On many occasions, the nightly observations reveal the presence of similar waves at both locations. Typically, the period of observed similar waves lay in the 2.2–4.5 h range, had large phase speeds (~ 77–331 m s−1) and large wavelengths (~ 1194–2746 km). The images of outgoing long-wave radiation activity of the National Oceanic and Atmospheric Administration (NOAA) and the high-resolution infrared images of KALPANA-1 satellite suggest that such waves possibly originated from some nearby convective sources. An analysis of their propagation characteristics in conjunction with SABER/TIMED temperature profiles and Horizontal Wind Model (HWM 2007) wind estimates suggest that the waves propagated over long distances (~ 1200–2000 km) in atmospheric ducts.

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Yue, Jia, Septi Perwitasari, Shuang Xu, Yuta Hozumi, Takuji Nakamura, Takeshi Sakanoi, Akinori Saito, Steven D. Miller, William Straka i Pingping Rong. "Preliminary Dual-Satellite Observations of Atmospheric Gravity Waves in Airglow". Atmosphere 10, nr 11 (28.10.2019): 650. http://dx.doi.org/10.3390/atmos10110650.

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Atmospheric gravity waves (AGWs) are among the important energy and momentum transfer mechanisms from the troposphere to the middle and upper atmosphere. Despite their understood importance in governing the structure and dynamics of these regions, mesospheric AGWs remain poorly measured globally, and largely unconstrained in numerical models. Since late 2011, the Suomi National Polar-orbiting Partnership (NPP) Visible/Infrared Imaging Radiometer Suite (VIIRS) day–night band (DNB) has observed global AGWs near the mesopause by virtue of its sensitivity to weak emissions of the OH* Meinel bands. The wave features, detectable at 0.75 km spatial resolution across its 3000 km imagery swath, are often confused by the upwelling emission of city lights and clouds reflecting downwelling nightglow. The Ionosphere, Mesosphere, upper Atmosphere and Plasmasphere (IMAP)/ Visible and near-Infrared Spectral Imager (VISI) O2 band, an independent measure of the AGW structures in nightglow based on the International Space Station (ISS) during 2012–2015, contains much less noise from the lower atmosphere. However, VISI offers much coarser resolution of 14–16 km and a narrower swath width of 600 km. Here, we present preliminary results of comparisons between VIIRS/DNB and VISI observations of AGWs, focusing on several concentric AGW events excited by the thunderstorms over Eastern Asia in August 2013. The comparisons point toward suggested improvements for future spaceborne airglow sensor designs targeting AGWs.

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López-González, M. J., E. Rodríguez, M. García-Comas, V. Costa, M. G. Shepherd, G. G. Shepherd, V. M. Aushev i S. Sargoytchev. "Climatology of planetary wave type oscillations with periods of 2–20 days derived from O2 atmospheric and OH(6-2) airglow observations at mid-latitude with SATI". Annales Geophysicae 27, nr 9 (30.09.2009): 3645–62. http://dx.doi.org/10.5194/angeo-27-3645-2009.

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Abstract. The presence of planetary wave type oscillations at mid-latitudes in the mesosphere/lower thermosphere region has been investigated using airglow observations. The observations were taken with a Spectral Airglow Temperature Imager (SATI) installed at Sierra Nevada Observatory (37.06° N, 3.38° W) at 2900 m height. Airglow data of the column emission rate of the O2 Atmospheric (0-1) band and of the OH Meinel (6-2) band and deduced rotational temperatures from 1998 to 2007 have been used in this study. From these observations a climatology of planetary wave type oscillations at this location is inferred. It has been found that the planetary wave type oscillations of 5-day period is predominant in our data throughout the year, with activity greater than 50% during March/April and October/November months. The planetary wave type oscillations of 2-day period is predominant during both solstices, being predominant during winter solstice in O2 while a 10-day oscillation appears throughout the year with activity around 20% and with maximum activity during spring and autumn equinoxes. The 16-day oscillation has maximum occurrence during autumn-winter while its activity is almost disappeared during spring-summer. No clear seasonal dependence of the amplitude of the planetary wave type oscillations was observed in the cases considered in this study. The waves simultaneously detected in the rotational temperatures deduced from both OH and O2 emissions usually show an upward energy propagation and are affected by dissipation processes.

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Takahashi, H., A. Onohara, K. Shiokawa, F. Vargas i D. Gobbi. "Atmospheric wave induced O2 and OH airglow intensity variations: effect of vertical wavelength and damping". Annales Geophysicae 29, nr 4 (7.04.2011): 631–37. http://dx.doi.org/10.5194/angeo-29-631-2011.

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Abstract. From nocturnal variations of the airglow O2 (0-1) and OH Meinel (6-2) band emission intensity and the rotational temperature, gravity waves and the damping effect in the MLT region were investigated. The data set was obtained from photometer measurements at Rikubetsu (43.5° N, 143.8° E), Japan, from March 2004 to August 2005. The ratio of the amplitude of oscillation and their phase difference between the two emissions were calculated when simultaneous periodic variations were observed. The ratio showed a linear correlation with the phase difference. The vertical wavelength and damping rate were estimated by using a model calculation carried out by previous works. The results show that the wave damping is significant when the vertical wavelength is shorter than 30–40 km. Krassovsky's parameter η, which represents a ratio between the emission intensity and temperature oscillations, was also calculated. The results show that the η also depends on the damping effect.

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Mlynczak, Martin G., Daniel K. Zhou i Steven M. Adler-Golden. "Kinetic and spectroscopic requirements for the inference of chemical heating rates and atomic hydrogen densities from OH Meinel band measurements". Geophysical Research Letters 25, nr 5 (1.03.1998): 647–50. http://dx.doi.org/10.1029/98gl00325.

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25

Pendleton, W. R., i M. J. Taylor. "The impact of L-uncoupling on Einstein coefficients for the OH Meinel (6,2) band: implications for Q-branch rotational temperatures". Journal of Atmospheric and Solar-Terrestrial Physics 64, nr 8-11 (maj 2002): 971–83. http://dx.doi.org/10.1016/s1364-6826(02)00051-2.

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McDade, I. C., E. J. Llewellyn, D. P. Murtagh i R. G. H. Greer. "Eton 5: Simultaneous rocket measurements of the OH meinel Δυ = 2 sequence and (8,3) band emission profiles in the nightglow". Planetary and Space Science 35, nr 9 (wrzesień 1987): 1137–47. http://dx.doi.org/10.1016/0032-0633(87)90020-1.

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Bhattacharya, Y., i A. J. Gerrard. "Correlations of mesospheric winds with subtle motion of the Arctic polar vortex". Atmospheric Chemistry and Physics Discussions 9, nr 4 (6.08.2009): 16549–62. http://dx.doi.org/10.5194/acpd-9-16549-2009.

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Abstract. This paper investigates the relationship between high latitude upper mesospheric winds and the state of the stratospheric polar vortex in the absence of major sudden stratospheric warmings. A ground based Michelson Interferometer stationed at Resolute Bay (74°43´ N, 94°58´ W) in the Canadian High Arctic is used to measure mesopause region neutral winds using the hydroxyl (OH) Meinel-band airglow emission (central altitude of ~85 km). These observed winds are compared to analysis winds in the upper stratosphere during November and December of 1995 and 1996; years characterized as cold, stable polar vortex periods. Correlation of mesopause wind speeds with those from the upper stratosphere is found to be significant for the 1996 season when the polar vortex is subtly displaced off its initial location by a strong Aleutian High. These mesopause winds are observed to lead stratospheric winds by approximately two days with increasing (decreasing) mesospheric winds predictive of decreasing (increasing) stratospheric winds. No statistically significant correlations are found for the 1995 season when there is no such displacement of the polar vortex.

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Bhattacharya, Y., i A. J. Gerrard. "Correlations of mesospheric winds with subtle motion of the Arctic polar vortex". Atmospheric Chemistry and Physics 10, nr 2 (19.01.2010): 431–36. http://dx.doi.org/10.5194/acp-10-431-2010.

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Abstract. This paper investigates the relationship between high latitude upper mesospheric winds and the state of the stratospheric polar vortex in the absence of major sudden stratospheric warmings. A ground based Michelson Interferometer stationed at Resolute Bay (74°43' N, 94°58' W) in the Canadian High Arctic is used to measure mesopause region neutral winds using the hydroxyl (OH) Meinel-band airglow emission (central altitude of ~85 km). These observed winds are compared to analysis winds in the upper stratosphere during November and December of 1995 and 1996; years characterized as cold, stable polar vortex periods. Correlation of mesopause wind speeds with those from the upper stratosphere is found to be significant for the 1996 season when the polar vortex is subtly displaced off its initial location by a strong Aleutian High. These mesopause winds are observed to lead stratospheric winds by approximately two days with increasing (decreasing) mesospheric winds predictive of decreasing (increasing) stratospheric winds. No statistically significant correlations are found for the 1995 season when there is no such displacement of the polar vortex.

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Mulligan, F. J., i R. P. Lowe. "OH-equivalent temperatures derived from ACE-FTS and SABER temperature profiles – a comparison with OH*(3-1) temperatures from Maynooth (53.2° N, 6.4° W)". Annales Geophysicae 26, nr 4 (13.05.2008): 795–811. http://dx.doi.org/10.5194/angeo-26-795-2008.

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Abstract. OH-equivalent temperatures were derived from all of the temperature profiles retrieved in 2004 and 2005 by the ACE-FTS instrument in a 5 degree band of latitude centred on a ground-based observing station at Maynooth. A globally averaged OH volume emission rate (VER) profile obtained from WINDII data was employed as a weighting function to compute the equivalent temperatures. The annual cycle of temperature thus produced was compared with the annual cycle of temperatures recorded at the ground-based station more than a decade earlier from the OH*(3-1) Meinel band. Both data sets showed excellent agreement in the absolute value of the temperature minimum (~162 K) and in its time of occurrence in the annual cycle at summer solstice. Away from mid-summer, however, the temperatures diverged and reach a maximum disagreement of more than 20 K in mid-winter. Comparison of the Maynooth ground-based data with the corresponding results from two nearby stations in the same time-period indicated that the Maynooth data are consistent with other ground stations. The temperature difference between the satellite and ground-based datasets in winter was reduced to 14–15 K by lowering the peak altitude of the weighting function to 84 km. An unrealistically low peak altitude would be required, however, to bring temperatures derived from the satellite into agreement with the ground-based data. OH equivalent temperatures derived from the SABER instrument using the same weighting function produced results that agreed well with ACE-FTS. When the OH 1.6 μm VER profile measured by SABER was used as the weighting function, the OH equivalent temperatures increased in winter as expected but the summer temperatures were reduced resulting in an approximately constant offset of 8.6±0.8 K between ground and satellite values with the ground values higher. Variability in both the altitude and width of the OH layer within a discernable seasonal variation were responsible for the changes introduced. The higher temperatures in winter were due to primarily to the lower altitude of the OH layer, while the colder summer temperatures were due to a thinner summer OH layer. We are not aware of previous reports of the effect of the layer width on ground-based temperatures. Comparison of OH-equivalent temperatures derived from ACE-FTS and SABER temperature profiles with OH*(3-1) temperatures from Wuppertal at 51.3° N which were measured during the same period showed a similar pattern to the Maynooth data from a decade earlier, but the warm offset of the ground values was lower at 4.5±0.5 K. This discrepancy between temperatures derived from ground-based instruments recording hydroxyl spectra and satellite borne instruments has been observed by other observers. Further work will be required by both the satellite and ground-based communities to identify the exact cause of this difference.

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Llewellyn, E. J., N. D. Lloyd, D. A. Degenstein, R. L. Gattinger, S. V. Petelina, A. E. Bourassa, J. T. Wiensz i in. "The OSIRIS instrument on the Odin spacecraft". Canadian Journal of Physics 82, nr 6 (1.06.2004): 411–22. http://dx.doi.org/10.1139/p04-005.

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The optical spectrograph and infrared imager system (OSIRIS) on board the Odin spacecraft is designed to retrieve altitude profiles of terrestrial atmospheric minor species by observing limb-radiance profiles. The grating optical spectrograph (OS) obtains spectra of scattered sunlight over the range 280800 nm with a spectral resolution of approximately 1 nm. The Odin spacecraft performs a repetitive vertical limb scan to sweep the OS 1 km vertical field of view over selected altitude ranges from approximately 10 to 100 km. The terrestrial absorption features that are superimposed on the scattered solar spectrum are monitored to derive the minor species altitude profiles. The spectrograph also detects the airglow, which can be used to study the mesosphere and lower thermosphere. The other part of OSIRIS is a three-channel infrared imager (IRI) that uses linear array detectors to image the vertical limb radiance over an altitude range of approximately 100 km. The IRI observes both scattered sunlight and the airglow emissions from the oxygen infrared atmospheric band at 1.27 µm and the OH (3-1) Meinel band at 1.53 µm. A tomographic inversion technique is used with a series of these vertical images to derive the two-dimensional distribution of the emissions within the orbit plane. PACS Nos.: 07.05.Pj, 07.60.Dq, 07.60.Rd, 07.87, 94.10.Dy, 94.10.Fa, 94.10.Gb, 94.10.Rk

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Skinner, Wilbert R., Jeng-Hwa Yee, Paul B. Hays i Mark D. Burrage. "Seasonal and local time variations in the O(1S) green line, O2 atmospheric band, and OH Meinel band emissions as measured by the High Resolution Doppler Imager". Advances in Space Research 21, nr 6 (styczeń 1998): 835–41. http://dx.doi.org/10.1016/s0273-1177(97)00684-4.

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Pant, T. K., D. Tiwari, S. Sridharan, R. Sridharan, S. Gurubaran, K. S. V. Subbarao i R. Sekar. "Evidence for direct solar control of the mesopause dynamics through dayglow and radar measurements". Annales Geophysicae 22, nr 9 (23.09.2004): 3299–303. http://dx.doi.org/10.5194/angeo-22-3299-2004.

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Abstract. The day-to-day measurements of the daytime intensities of hydroxyl (OH) Meinel (8-3) band airglow emissions at 731.6 and 740.2nm carried out from the equatorial station Thiruvananthapuram (8.5° N, 76.5° E, 0.5° dip) during the period of January-March 2001 have been investigated. This investigation provides evidence for the presence of a long period (≈16 days) wave modulating these intensities at the mesopause altitudes. Simultaneous radar measurements of zonal wind at ~87km, i.e. mesopause from Tirunelveli (8.7° N, 77.8° E, 0.33° dip), a location nearby, also reveal the presence of these long period oscillations. The daytime airglow and zonal wind undergo changes simultaneously. Similar modulations are seen in the solar 10.7cm flux also preceding dayglow and wind variabilities by 4-5 days. It is inferred in the present case that the changes in the solar flux are the cause of the generation of this long period wave in the atmosphere below the mesosphere. The oscillations in the measured dayglow intensities in the mesopause region and the winds at ~87km are resulting from the modulation caused by this wave in this region after a delay of 4-5 days.

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33

Jenniskens, Peter, i Christophe O. Laux. "Search for the OH (X2Π) Meinel Band Emission in Meteors as a Tracer of Mineral Water in Comets: Detection of N2+ (A-X)". Astrobiology 4, nr 1 (marzec 2004): 109–21. http://dx.doi.org/10.1089/153110704773600276.

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34

Todd Clancy, R., Brad J. Sandor, Antonio García-Muñoz, Franck Lefèvre, Michael D. Smith, Michael J. Wolff, Franck Montmessin, Scott L. Murchie i Hari Nair. "First detection of Mars atmospheric hydroxyl: CRISM Near-IR measurement versus LMD GCM simulation of OH Meinel band emission in the Mars polar winter atmosphere". Icarus 226, nr 1 (wrzesień 2013): 272–81. http://dx.doi.org/10.1016/j.icarus.2013.05.035.

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35

Lednyts'kyy, O., C. von Savigny, K. U. Eichmann i M. G. Mlynczak. "Atomic oxygen retrievals in the MLT region from SCIAMACHY nightglow limb measurements". Atmospheric Measurement Techniques Discussions 7, nr 10 (30.10.2014): 10829–81. http://dx.doi.org/10.5194/amtd-7-10829-2014.

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Abstract. Vertical profiles of atomic oxygen concentration in the mesosphere and lower thermosphere (MLT) region were retrieved from sun-synchronous SCIAMACHY/Envisat limb observations of the oxygen 557.7 nm green line emission occurring in the terrestrial nightglow. A band pass filter with noise detection was applied to eliminate contributions from other emissions, the impact of noise and auroral activity. Assuming horizontal homogeneity of each atmospheric layer, and absence of absorption and scattering, vertical volume emission rate profiles were retrieved from integrated limb emission rate profiles. The radiative transfer problem was treated with a linear forward model and inverted using regularized total least squares minimization. Atomic oxygen concentration ([O]) profiles were retrieved at altitudes from 85 to 105 km with approximately 4 km vertical resolution for the period from August 2002 to April 2012 at a constant local time (LT) of approximately 22:00. The retrieval of [O] profiles was based on the generally accepted 2-step Barth transfer scheme including consideration of quenching processes and the use of different available sources of temperature and atmospheric density profiles. A sensitivity analysis was performed for the retrieved [O] profiles to estimate the maximum uncertainty, assuming independent contributions of uncertainty components. The retrieved [O] profiles were compared with reference [O] profiles measured by SABER/TIMED and modelled using NRLMSISE-00 and SD-WACCM4. A comparison of the retrieved [O] profiles with the reference [O] profiles enabled the selection of the most appropriate photochemical model accounting for quenching processes and the most appropriate source of temperature and density profiles for further application of our approach to the [O] profile retrieval. The obtained [O] profile time series show characteristic seasonal variations in agreement with atmospheric models and satellite observations based on analysis of OH Meinel band emissions. Furthermore, a pronounced 11 year solar cycle variation can be identified in the atomic oxygen concentration time series, which will be the subject of further studies.

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36

Lednyts'kyy, O., C. von Savigny, K. U. Eichmann i M. G. Mlynczak. "Atomic oxygen retrievals in the MLT region from SCIAMACHY nightglow limb measurements". Atmospheric Measurement Techniques 8, nr 3 (4.03.2015): 1021–41. http://dx.doi.org/10.5194/amt-8-1021-2015.

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Abstract. Vertical distributions of atomic oxygen concentration ([O]) in the mesosphere and lower thermosphere (MLT) region were retrieved from sun-synchronous SCIAMACHY/Envisat (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY on board the Environmental Satellite) limb measurements of the oxygen 557.7 nm green line emission in the terrestrial nightglow. A band pass filter was applied to eliminate contributions from other emissions, the impact of measurement noise and auroral activity. Vertical volume emission rate profiles were retrieved from integrated limb-emission rate profiles under the assumption that each atmospheric layer is horizontally homogeneous and absorption and scattering can be neglected. The radiative transfer problem was solved using regularized total least squares minimization in the inversion procedure. Atomic oxygen concentration profiles were retrieved from data collected for altitudes in the range 85–105 km with approximately 4 km vertical resolution during the time period from August 2002 to April 2012 at approximately 22:00 local time. The retrieval of [O] profiles was based on the generally accepted two-step Barth transfer scheme including consideration of quenching processes and the use of different available sources of temperature and atmospheric density profiles. A sensitivity analysis was performed for the retrieved [O] profiles to estimate maximum uncertainties assuming independent contributions of uncertainty components. Errors in photochemical model parameters depending on temperature uncertainties and random errors of model parameters contribute less than 50% to the overall [O] retrieval error. The retrieved [O] profiles were compared with reference [O] profiles provided by SABER/TIMED (Sounding of the Atmosphere using Broadband Emission Radiometry instrument on board the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics satellite) or by the NRLMSISE-00 (Naval Research Laboratory Mass Spectrometer and Incoherent Scatter radar Extended model, year: 2000) and SD-WACCM4 (Whole Atmosphere Community Climate Model with Specified Dynamics, version 4). A comparison of the retrieved [O] profiles with the reference [O] profiles led to the conclusion that the photochemical model taking into account quenching of O(1S) by O2, O(3P), and N2 and the SABER/TIMED model as a source of temperature and density profiles are the most appropriate choices for our case. The retrieved [O] profile time series exhibits characteristic seasonal variations in agreement with satellite observations based on analysis of OH Meinel band emissions and atmospheric models. A pronounced 11-year solar cycle variation can also be identified in the retrieved atomic oxygen concentration time series.

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37

Kowalewski, S., C. von Savigny, M. Palm, I. C. McDade i J. Notholt. "On the impact of the temporal variability of the collisional quenching process on the mesospheric OH emission layer: a study based on SD-WACCM4 and SABER". Atmospheric Chemistry and Physics 14, nr 18 (24.09.2014): 10193–210. http://dx.doi.org/10.5194/acp-14-10193-2014.

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Abstract. The mesospheric OH Meinel emissions are subject of many theoretical and observational studies devoted to this part of the atmosphere. Depending on the initial vibrational level of excitation the altitude of the considered OH Meinel emission is systematically shifted, which has important implications for the intercomparison of different studies considering different transition bands. Previous model studies suggest that these vertical shifts are essentially caused by the process of collisional quenching with atomic oxygen. Following this hypothesis, a recent study found experimental evidence of a coherent seasonality at tropical latitudes between vertical shifts of different OH Meinel bands and changes in atomic oxygen concentrations. Despite the consistent finding of the above mentioned hypothesis, it cannot be excluded that the actual temporal variability of the vertical shifts between different OH Meinel bands may in addition be controlled or even dominated by other processes. It remains an open question whether the observed temporal evolution is indeed mainly controlled by the modulation of the collisional quenching process with atomic oxygen. By means of a sensitivity study which employs a quenching model to simulations made with the SD-WACCM4 chemistry climate model, we aim at assessing this question. From this study we find that the observed seasonality of vertical OH Meinel shifts is only partially controlled by temporal changes in atomic oxygen concentrations, while molecular oxygen has another noticeable impact on the vertical OH Meinel shifts. This in particular becomes evident for the diurnal variability of vertical OH Meinel shifts, which reveal only a poor correlation with the atomic oxygen species. Furthermore, changes in the H + O3 source gases provide another mechanism that can potentially affect the diurnal variability in addition. By comparison with limb radiance observations from the SABER/TIMED satellite this provides an explanation for the less evident diurnal response between changes in O concentrations and vertical OH Meinel shifts. On the other hand, at seasonal timescales the coherency between both quantities is again evident in SABER/TIMED but less pronounced compared to our model simulations.

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38

Le Texier, H., S. Solomon i R. R. Garcia. "Seasonal variability of the OH Meinel bands". Planetary and Space Science 35, nr 8 (sierpień 1987): 977–89. http://dx.doi.org/10.1016/0032-0633(87)90002-x.

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Franzen, Christoph, Patrick Joseph Espy, Niklas Hofmann, Robert Edward Hibbins i Anlaug Amanda Djupvik. "Airglow Derived Measurements of Q-Branch Transition Probabilities for Several Hydroxyl Meinel Bands". Atmosphere 10, nr 10 (22.10.2019): 637. http://dx.doi.org/10.3390/atmos10100637.

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Spectroscopic measurements of the hydroxyl (OH) airglow emissions are often used to infer neutral temperatures near the mesopause. Correct Einstein coefficients for the various transitions in the OH airglow are needed to calculate accurate temperatures. However, studies from some studys showed experimentally and theoretically that the most commonly used Einstein spontaneous emission transition probabilities for the Q-branch of the OH Meinel (6,2) transition are overestimated. Extending their work to several Δv = 2 and 3 transitions from v′ = 3 to 9, we have determined Einstein coefficients for the first four Q-branch rotational lines. These have been derived from high resolution, high signal to noise spectroscopic observations of the OH airglow in the night sky from the Nordic Optical Telescope. The Q-branch Einstein coefficients calculated from these spectra show that values currently tabulated in the HITRAN database overestimate many of the Q-branch transition probabilities. The implications for atmospheric temperatures derived from OH Q-branch measurements are discussed.

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40

Chadney, Joshua M., Daniel K. Whiter i Betty S. Lanchester. "Effect of water vapour absorption on hydroxyl temperatures measured from Svalbard". Annales Geophysicae 35, nr 3 (24.03.2017): 481–91. http://dx.doi.org/10.5194/angeo-35-481-2017.

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Abstract. We model absorption by atmospheric water vapour of hydroxyl airglow emission using the HIgh-resolution TRANsmission molecular absorption database (HITRAN2012). Transmission coefficients are provided as a function of water vapour column density for the strongest OH Meinel emission lines in the (8–3), (5–1), (9–4), (8–4), and (6–2) vibrational bands. These coefficients are used to determine precise OH(8–3) rotational temperatures from spectra measured by the High Throughput Imaging Echelle Spectrograph (HiTIES), installed at the Kjell Henriksen Observatory (KHO), Svalbard. The method described in this paper also allows us to estimate atmospheric water vapour content using the HiTIES instrument.

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41

Kalogerakis, Konstantinos S. "Technical note: Bimodality in mesospheric OH rotational population distributions and implications for temperature measurements". Atmospheric Chemistry and Physics 19, nr 4 (28.02.2019): 2629–34. http://dx.doi.org/10.5194/acp-19-2629-2019.

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Abstract. Emissions from the OH Meinel bands are routinely used to determine rotational temperatures that are considered proxies for the kinetic temperature near the mesopause region. Previous observations determined OH rotational temperatures that show a dependence on the vibrational level, with the temperature rising overall as the OH vibrational quantum number v increases. The source of this trend is not well understood and has generally been attributed to deviations from thermodynamic equilibrium. This technical note demonstrates that the existence of bimodal OH rotational population distributions is an inherent feature of rotational relaxation in gases and can provide an explanation for the previously reported temperature trend. The use of only a few lines from rotational transitions involving low rotational quantum numbers to determine rotational temperatures does not account for the bimodality of the OH rotational population distributions and leads to systematic errors overestimating the OH rotational temperature. This note presents selected examples, discusses the relevant implications, and considers strategies that could lead to more reliable OH rotational temperature determination.

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42

López-González, M. J., D. P. Murtagh, P. J. Espy, J. J. López-Moreno, R. Rodrigo i G. Witt. "A model study of the temporal behaviour of the emission intensity and rotational temperature of the OH Meinel bands for high-latitude summer conditions". Annales Geophysicae 14, nr 1 (31.01.1996): 59–67. http://dx.doi.org/10.1007/s00585-996-0059-x.

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Abstract. The temporal variation of OH* emission and weighted rotational temperature has been studied for high-latitude summer conditions. Observations for 60°N latitude show OH weighted temperatures that always exceed 145 K even during periods of noctilucent clouds. Using a one-dimensional model the effects in excited OH concentration produced by changes in temperature, eddy diffusion, and water concentration have been analysed. We are forced to conclude that there remains a discrepancy between the OH temperatures predicted by the model and that obtained from OH* measurements. An increase in OH* concentration from June to the beginning of August, followed by a slow decrease during August has been obtained in agreement with the measurements. The 16-day modulation present in the measurements was simulated in a simple manner by varying the temperature in the mesopause region. This variation produces periodic modulations in both OH* concentration and weighted temperature of 16 days. The results show the temperature leading the OH* column concentration by three days. This phase shift is also present in the observations.

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TAKANO, Motoharu, Takashi WATANABE i Masatoshi NAKAMURA. "Rocket measurements of O2 atmospheric (0-0) and OH meinel bands in the night airglow." Journal of geomagnetism and geoelectricity 42, nr 10 (1990): 1193–208. http://dx.doi.org/10.5636/jgg.42.1193.

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von Savigny, C., i O. Lednyts'kyy. "On the relationship between atomic oxygen and vertical shifts between OH Meinel bands originating from different vibrational levels". Geophysical Research Letters 40, nr 21 (4.11.2013): 5821–25. http://dx.doi.org/10.1002/2013gl058017.

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45

Viereck, R. A., i C. S. Deehr. "On the interaction between gravity waves and the OH Meinel (6-2) and the O2atmospheric (0-1) bands in the polar night airglow". Journal of Geophysical Research 94, A5 (1989): 5397. http://dx.doi.org/10.1029/ja094ia05p05397.

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46

Nishiyama, Takanori, Makoto Taguchi, Hidehiko Suzuki, Peter Dalin, Yasunobu Ogawa, Urban Brändström i Takeshi Sakanoi. "Temporal evolutions of $$\text {N}_2^+$$ Meinel (1,2) band near $$1.5.\,\upmu \text {m}$$ associated with aurora breakup and their effects on mesopause temperature estimations from OH Meinel (3,1) band". Earth, Planets and Space 73, nr 1 (29.01.2021). http://dx.doi.org/10.1186/s40623-021-01360-0.

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AbstractWe have carried out ground-based NIRAS (Near-InfraRed Aurora and airglow Spectrograph) observations at Syowa station, Antarctic ($$69.0^{\circ }\text {S}$$ 69 . 0 ∘ S , $$39.6^{\circ }\text {E}$$ 39 . 6 ∘ E ) and Kiruna ($$67.8^{\circ }\text {N}$$ 67 . 8 ∘ N , $$20.4^{\circ }\text {E}$$ 20 . 4 ∘ E ), Sweden for continuous measurements of hydroxyl (OH) rotational temperatures and a precise evaluation of auroral contaminations to OH Meinel (3,1) band. A total of 368-nights observations succeeded for 2 winter seasons, and 3 cases in which $$\text {N}_2^+$$ N 2 + Meinel (1,2) band around $$1.5\,\mu \text {m}$$ 1.5 μ m was significant were identified. Focusing on two specific cases, detailed spectral characteristics with high temporal resolutions of 30 s are presented. Intensities of $$\text {N}_2^+$$ N 2 + band were estimated to be 228 kR and 217 kR just at the moment of the aurora breakup and arc intensification during pseudo breakup, respectively. At a wavelength of $$\text {P}_1(2)$$ P 1 ( 2 ) line ($$\sim 1523 \,\text {nm}$$ ∼ 1523 nm ), $$\text {N}_2^+$$ N 2 + emissions were almost equal to or greater than the OH line intensity. On the other hand, at a wavelength of $$\text {P}_1(4)$$ P 1 ( 4 ) line ($$\sim 1542 \,\text {nm}$$ ∼ 1542 nm ), the OH line was not seriously contaminated and still dominant to $$\text {N}_2^+$$ N 2 + emissions. Furthermore, we evaluated $$\text {N}_2^+$$ N 2 + (1,2) band effects on OH rotational temperature estimations quantitatively for the first time. Auroral contaminations from $$\text {N}_2^+$$ N 2 + (1,2) band basically lead negative bias in OH rotational temperature estimated by line-pair-ratio method with $$\text {P}_1(2)$$ P 1 ( 2 ) and $$\text {P}_1(4)$$ P 1 ( 4 ) lines in OH (3,1) band. They possibly cause underestimations of OH rotational temperatures up to 40 K. In addition, $$\text {N}_2^+$$ N 2 + (1,2) band contaminations were temporally limited to a moment around the aurora breakup. This is consistent with proceeding studies reporting that enhancements of $$\text {N}_2^+$$ N 2 + (1,2) band were observed associated with International Brightness Coefficient 2–3 auroras. It is also suggested that the contaminations would be neglected in the polar cap and the sub-auroral zone, where strong aurora intensification is less observed. Further spectroscopic investigations at these wavelengths are needed especially for more precise evaluations of $$\text {N}_2^+$$ N 2 + (1,2) band contaminations. For example, simultaneous 2-D imaging observation and spectroscopic measurement with high spectral resolutions for airglow in OH (3,1) band will make great advances in more robust temperature estimations in the auroral zone.

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von Savigny, C. "First near-global retrievals of OH rotational temperatures from satellite-based Meinel band emission measurements". Geophysical Research Letters 31, nr 15 (2004). http://dx.doi.org/10.1029/2004gl020410.

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Panka, Peter A., Alexander A. Kutepov, Yajun Zhu, Martin Kaufmann, Konstantinos S. Kalogerakis, Ladislav Rezac, Artem G. Feofilov, Daniel R. Marsh i Diego Janches. "Simultaneous retrievals of nighttime O( 3 P) and total OH densities from satellite observations of Meinel band emissions". Geophysical Research Letters, 6.12.2020. http://dx.doi.org/10.1029/2020gl091053.

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