Interannual variability of the nonmigrating semidiurnal tide at high latitudes and stationary planetary wave in the opposite hemispheres

Abstract. FORMOSAT-3/COSMIC temperature data during 2009 to 2010 are analysed for tides in the middle atmosphere from ~ 10 to 50 km. COSMIC is a set of six micro satellites in near sun synchronous orbits with 30° orbital separations and provides good phase space sampling of tides. Short term tidal variability is deduced by considering ± 10 days' data together. The DW1 tide is found to peak over the equator at 30 km. It maximises and slightly shifts poleward during winters and thus is attributed to ozone absorption. Over mid and high latitudes, DW1 and the non-migrating tides DS0 and DW2 are intermittent in nature. Numerical experiments in the current study show that these could be a result of aliasing as they are found to occur at times of steep rise or fall in the mean temperature, particularly during the SSW of 2010. Further, stationary planetary wave components are found to be of very large amplitudes in the northern hemispheres reaching 18 K at 30 km over 65° N. By using data from COSMIC over shorter durations, aliasing between SPW and non-migrating tides is reduced and thus results in the large amplitudes of the former. This study clearly indicates that non-linear interactions are not a very important source of generation of the non migrating tides in the high latitude winter hemisphere. There is also a modulation of SPW1 by ~ 60 days in the high latitudes, which was not seen earlier.

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Migrating and non-migrating tides observed in the stratosphere from FORMOSAT-3/COSMIC temperature retrievals

Annales Geophysicae ◽

10.5194/angeo-38-421-2020 ◽

2020 ◽

Vol 38 (2) ◽

pp. 421-435 ◽

Cited By ~ 1

Author(s):

Uma Das ◽

William E. Ward ◽

Chen Jeih Pan ◽

Sanat Kumar Das

Keyword(s):

Planetary Wave ◽

Middle Atmosphere ◽

High Latitudes ◽

Sudden Stratospheric Warming ◽

Short Term ◽

The Mean ◽

Tidal Variability ◽

Using Data ◽

Stationary Planetary Wave ◽

Linear Interactions

Abstract. Formosa Satellite-3 and Constellation Observing System for Meteorology, Ionosphere and Climate (FORMOSAT-3/COSMIC) temperature data during October 2009–December 2010 are analysed for tides in the middle atmosphere from ∼10 to 50 km. COSMIC is a set of six micro-satellites in near-Sun-synchronous orbits with 30∘ orbital separations that provides good phase space sampling of tides. Short-term tidal variability is deduced by considering ±10 d data together. The migrating diurnal (DW1) tide is found to peak over the Equator at 30 km. It maximises and slightly shifts poleward during winters. Over middle and high latitudes, DW1 and the non-migrating diurnal tides with wavenumber 0 (DS0) and wavenumber 2 (DW2) are intermittent in nature. Numerical experiments in the current study show that these could be a result of aliasing as they are found to occur at times of a steep rise or fall in the mean temperature, particularly during the sudden stratospheric warming (SSW) of 2010. Further, the stationary planetary wave component of wavenumber 1 (SPW1) is found to be of very large amplitudes in the Northern Hemisphere, reaching 18 K at 30 km over 65∘ N. By using data from COSMIC over shorter durations, it is shown that aliasing between stationary planetary wave and non-migrating tides is reduced and thus results in the large amplitudes of the former. This study clearly indicates that non-linear interactions are not a very important source for the generation of non-migrating tides in the middle- and high-latitude winter stratosphere. There is also a modulation of SPW1 by a ∼60 d oscillation in the high latitudes, which was not seen earlier.

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Interannual variability of precipitable water

Annales Geophysicae ◽

10.1007/s00585-996-0464-1 ◽

1996 ◽

Vol 14 (4) ◽

pp. 464-467 ◽

Cited By ~ 1

Author(s):

R. P. Kane

Keyword(s):

Interannual Variability ◽

Southern Hemisphere ◽

Northern Hemisphere ◽

Precipitable Water ◽

Radiosonde Data ◽

High Latitudes ◽

Zonal Winds ◽

Low Latitudes ◽

Linear Trends

Abstract. The 12-month running means of the surface-to-500 mb precipitable water obtained from analysis of radiosonde data at seven selected locations showed three types of variability viz: (1) quasi-biennial oscillations; these were different in nature at different latitudes and also different from the QBO of the stratospheric tropical zonal winds; (2) decadal effects; these were prominent at middle and high latitudes and (3) linear trends; these were prominent at low latitudes, up trends in the Northern Hemisphere and downtrends in the Southern Hemisphere.

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Relationship between stationary planetary wave activity and the East Asian winter monsoon

Journal of Geophysical Research Atmospheres ◽

10.1029/2004jd005669 ◽

2005 ◽

Vol 110 (D14) ◽

pp. n/a-n/a ◽

Cited By ~ 120

Author(s):

Wen Chen ◽

Song Yang ◽

Rong-Hui Huang

Keyword(s):

Planetary Wave ◽

East Asian Winter Monsoon ◽

East Asian ◽

Wave Activity ◽

Winter Monsoon ◽

Asian Winter Monsoon ◽

Stationary Planetary Wave

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Comparison of Key Characteristics of Remarkable SSW Events in the Southern and Northern Hemisphere

10.5194/egusphere-egu21-7702 ◽

2021 ◽

Author(s):

Michal Kozubek ◽

Peter Krizan

Keyword(s):

Northern Hemisphere ◽

Planetary Wave ◽

Polar Vortex ◽

Wave Number ◽

Strong Activity ◽

Key Characteristics ◽

Zonal Wave Number ◽

Show Difference ◽

Temperature Enhancement ◽

Stationary Planetary Wave

<p>An exceptionally strong sudden stratospheric warming (SSW) in the Southern Hemisphere (SH) during September 2019 was observed. Because SSW in the SH is very rare, comparison with the only recorded major SH SSW is done. According to World Meteorological Organization (WMO) definition, the SSW in 2019 has to be classified as minor. The cause of SSW in 2002 was very strong activity of stationary planetary wave with zonal wave-number (ZW) 2, which reached its maximum when the polar vortex split into two circulations with polar temperature enhancement by 30 K/week and it penetrated deeply to the lower stratosphere and upper troposphere. On the other hand, the minor SSW in 2019 involved an exceptionally strong wave-1 planetary wave and a large polar temperature enhancement by 50.8 K/week, but it affected mainly the middle and upper stratosphere. The strongest SSW in the Northern Hemisphere was observed in 2009. This study provides comparison of two strongest SSW in the SH and the strongest SSW in the NH to show difference between two hemispheres and possible impact to the lower or higher layers.</p>

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Interannual variations of stationary planetary wave activity in the northern winter troposphere and stratosphere and their relations to NAM and SST

Journal of Geophysical Research Atmospheres ◽

10.1029/2003jd003834 ◽

2003 ◽

Vol 108 (D24) ◽

pp. n/a-n/a ◽

Cited By ~ 57

Author(s):

Wen Chen ◽

Masaaki Takahashi ◽

Hans-F. Graf

Keyword(s):

Planetary Wave ◽

Wave Activity ◽

Interannual Variations ◽

Northern Winter ◽

Stationary Planetary Wave

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Interannual Variability of Stratospheric Final Warming in the Southern Hemisphere and its Tropospheric Origin

Journal of Climate ◽

10.1175/jcli-d-20-0945.1 ◽

2021 ◽

pp. 1-59

Author(s):

Soichiro Hirano ◽

Masashi Kohma ◽

Kaoru Sato

Keyword(s):

Interannual Variability ◽

Southern Hemisphere ◽

Reanalysis Data ◽

Stationary Waves ◽

High Latitudes ◽

Wave Source ◽

Barotropic Model ◽

Stratospheric Final Warming ◽

Zonal Wavenumber ◽

Favorable Conditions

AbstractThe relation between interannual variability of stratospheric final warming (SFW) and tropospheric circulation in the Southern Hemisphere (SH) is explored using reanalysis data and a linear barotropic model. The analysis is focused on quasi-stationary waves with zonal wavenumber 1 (s = 1 QSWs; s is zonal wavenumber), which are the dominant component of the SH extratropical planetary waves.First, interannual variability of SFW is investigated in terms of amplitudes of stratospheric and tropospheric s = 1 QSWs, and wave transmission properties of the mean flow from the late austral winter to spring. Upward Eliassen–Palm flux due to s = 1 QSWs is larger from the stratosphere down to the middle troposphere in early-SFW years than late-SFW years. More favorable conditions for propagation of s = 1 stationary waves into the stratosphere are identified in early-SFW years. These results indicate that the amplification of tropospheric s = 1 QSWs and the favorable conditions for their propagation into the stratosphere lead to the amplification of stratospheric s = 1 QSWs, and hence earlier SFWs.Next, numerical calculations using a linear barotropic model are performed to explore how tropospheric s = 1 QSWs at high latitudes amplifies in early-SFW years. By using tropical Rossby wave source and horizontal winds in the reanalysis data as a source and background field, respectively, differences in s = 1 steady responses between early- and late-SFWs are examined at high latitudes. It is suggested that the larger amplitudes of tropospheric s = 1 QSWs in early-SFW years are attributed to differences in wave propagation characteristics associated with structure of the midlatitude jets in austral spring.

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