Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions
Using 3 years (2013–2015) of O<sub>2</sub>(0–1) and OH(6–2) band nightglow emission intensities and corresponding rotational temperatures as tracers of mesospheric dynamics, we have investigated large- and small-timescale variations in the mesosphere over a low-latitude location, Guru...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2017-02-01
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| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/35/227/2017/angeo-35-227-2017.pdf |
| _version_ | 1811338522691371008 |
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| author | R. P. Singh R. P. Singh D. Pallamraju |
| author_facet | R. P. Singh R. P. Singh D. Pallamraju |
| author_sort | R. P. Singh |
| collection | DOAJ |
| description | Using 3 years (2013–2015) of O<sub>2</sub>(0–1) and OH(6–2) band nightglow
emission intensities and corresponding rotational temperatures as tracers of
mesospheric dynamics, we have investigated large- and small-timescale
variations in the mesosphere over a low-latitude location, Gurushikhar, Mount
Abu (24.6° N, 72.8° E), in India. Both O<sub>2</sub> and OH
intensities show variations similar to those of the number of
sunspots and F10.7 cm radio flux with coherent periodicities of
150 ± 2.1, 195 ± 3.6, 270 ± 6.4, and 420 ± 14.8 days,
indicating a strong solar influence on mesospheric dynamics. In addition,
both mesospheric airglow intensities also showed periodicities of
84 ± 0.6, 95 ± 0.9, and 122 ± 1.3 days which are of
atmospheric origin. With regard to the variability of the order of a few
days, O<sub>2</sub> and OH intensities were found to be correlated, in general,
except when altitude-dependent atmospheric processes were operative. To
understand mesospheric gravity wave behavior over the long term, we have
carried out a statistical study using the periodicities derived from the
nocturnal variations in all four parameters (O<sub>2</sub> and OH intensities and
their respective temperatures). It was found that the major wave periodicity
of around 2 h duration is present in all the four parameters. Our analyses
also reveal that the range of periods in O<sub>2</sub> and OH intensities and
temperatures is 11 to 24 and 20 to 60 min, respectively. Periods less than
15 min were not present in the temperatures but were prevalent in both
emission intensities. No seasonal dependence was found in either the wave
periodicities or the number of their occurrence. |
| first_indexed | 2024-04-13T18:12:09Z |
| format | Article |
| id | doaj.art-5957e68426dc49f49d2b3ce9651bbfb7 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-04-13T18:12:09Z |
| publishDate | 2017-02-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-5957e68426dc49f49d2b3ce9651bbfb72022-12-22T02:35:51ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762017-02-013522723710.5194/angeo-35-227-2017Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissionsR. P. Singh0R. P. Singh1D. Pallamraju2Space and Atmospheric Sciences Division, Physical Research Laboratory, Ahmedabad, IndiaDepartment of Physics, Sardar Patel University, Vallabh Vidyanagar, IndiaSpace and Atmospheric Sciences Division, Physical Research Laboratory, Ahmedabad, IndiaUsing 3 years (2013–2015) of O<sub>2</sub>(0–1) and OH(6–2) band nightglow emission intensities and corresponding rotational temperatures as tracers of mesospheric dynamics, we have investigated large- and small-timescale variations in the mesosphere over a low-latitude location, Gurushikhar, Mount Abu (24.6° N, 72.8° E), in India. Both O<sub>2</sub> and OH intensities show variations similar to those of the number of sunspots and F10.7 cm radio flux with coherent periodicities of 150 ± 2.1, 195 ± 3.6, 270 ± 6.4, and 420 ± 14.8 days, indicating a strong solar influence on mesospheric dynamics. In addition, both mesospheric airglow intensities also showed periodicities of 84 ± 0.6, 95 ± 0.9, and 122 ± 1.3 days which are of atmospheric origin. With regard to the variability of the order of a few days, O<sub>2</sub> and OH intensities were found to be correlated, in general, except when altitude-dependent atmospheric processes were operative. To understand mesospheric gravity wave behavior over the long term, we have carried out a statistical study using the periodicities derived from the nocturnal variations in all four parameters (O<sub>2</sub> and OH intensities and their respective temperatures). It was found that the major wave periodicity of around 2 h duration is present in all the four parameters. Our analyses also reveal that the range of periods in O<sub>2</sub> and OH intensities and temperatures is 11 to 24 and 20 to 60 min, respectively. Periods less than 15 min were not present in the temperatures but were prevalent in both emission intensities. No seasonal dependence was found in either the wave periodicities or the number of their occurrence.https://www.ann-geophys.net/35/227/2017/angeo-35-227-2017.pdf |
| spellingShingle | R. P. Singh R. P. Singh D. Pallamraju Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions Annales Geophysicae |
| title | Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions |
| title_full | Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions |
| title_fullStr | Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions |
| title_full_unstemmed | Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions |
| title_short | Large- and small-scale periodicities in the mesosphere as obtained from variations in O<sub>2</sub> and OH nightglow emissions |
| title_sort | large and small scale periodicities in the mesosphere as obtained from variations in o sub 2 sub and oh nightglow emissions |
| url | https://www.ann-geophys.net/35/227/2017/angeo-35-227-2017.pdf |
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