Diurnal variations of upper tropospheric and lower stratospheric winds over Japan as revealed with middle and upper atmosphere radar (34.85°N, 136.10°E) and five reanalysis data sets

Sakazaki, Takatoshi; Fujiwara, Masatomo; Hashiguchi, Hiroyuki

doi:10.1029/2010jd014550

Cited by 5 publications

(5 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the DT amplitudes were rather weak in the middle-mode height coverage, here we only provide the phase result in the height range of 3.5-9.0 km. Clearly, the observed DT phase profiles correspond well with those from the MERRA data set "inst6_3d_ana_Nv", which resembles the MU radar observational results by Sakazaki et al (2010) that the observed DT phase agrees well with that from the reanalysis data, while they clearly deviate from the GSWM-02 model results. For the zonal wind shown in Fig.…”

Section: Monthly Averaged Dtsupporting

confidence: 74%

“…However, the VHF data are still not abundant and the studies are inadequate (Williams and Avery, 1992;Sasi et al, 2001;Riggin et al, 2002;Vaughan and Worthington, 2007;Ramkumar et al, 2010;Chandrasekhar Sarma et al, 2011;Sakazaki et al, 2010). Supported by the Meridian Space Weather Monitoring Project, the Wuhan University (WHU) VHF radar was established in 2011 at Chongyang (114.14 • E, 29.53 • N).…”

mentioning

confidence: 99%

See 1 more Smart Citation

WHU VHF radar observations of the diurnal tide and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N), China

et al. 2015

View full text Add to dashboard Cite

Abstract. The diurnal tide (DT) and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N) were studied based on the newly established Wuhan University (WHU) VHF radar observations with the height intervals of 0.145 km (below 9 km) and 0.58 km (above 9 km) in the whole year of 2012. We find that the DT was the dominant tidal component and showed remarkable height and season variations. A prominent seasonally dependent height variability characteristic is that maximum DT amplitude usually occurs around 6 km in the winter and spring months, which might be due to the tidal wave energy concentration arising from the reflections from the strong eastward tropospheric jet around 13 km and the ground surface. Our results suggest that the background wind is a crucial cause for height variability and seasonal variability of DT. In April 2012, a notable strengthening of DT is observed. Meanwhile, the significant higher harmonics of tides, i.e., the semidiurnal, terdiurnal, and even quarterdiurnal tides, can also be observed, which has seldom been reported. Interestingly, these four tidal components displayed consistent short-term variability, implying that they were excited by the same dramatically varying tidal source. In addition, we identified two symptoms of the coupling of DT and planetary waves (PWs), which can also lead to the short-term DT variability. One is the sum and difference interactions between DT and PWs, causing the tidal amplitude short-term variability as a consequence of the energy exchange among the interacting waves. The other one is the modulation of DT by PWs, leading to that the amplitude of DT varies with the periods of the PWs.

show abstract

Section: Monthly Averaged Dtsupporting

confidence: 74%

mentioning

confidence: 99%

WHU VHF radar observations of the diurnal tide and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N), China

et al. 2015

View full text Add to dashboard Cite

show abstract

“…[17] For temporally continuous data such as atmospheric radar data [e.g., Sakazaki et al, 2010], diurnal variations are obtained simply by producing the local-time composite using all data in the period concerned. In contrast, for SABER data, due to the slow local time precession of the satellite, tidal components derived from the "simple local-time composite" could suffer from sampling issues due to changes in the background (longer than a day) temperature with time [Forbes et al, 1997].…”

Section: Methodsmentioning

confidence: 99%

“…From the troposphere to the lower stratosphere (below 22 km), Sakazaki et al [2010] compared horizontal diurnal winds in six reanalyses with those observed with the middle atmosphere (MU) radar at (35°N, 136°E) for 23 years and showed that reanalyses reproduce diurnal winds reasonably well. Pirscher et al [2010], using the National Centers for Environmental Prediction (NCEP) and the European Centre for Medium‐range Weather Forecasts (ECMWF) forecast data (not (re)analysis data) for two years, also showed that they are in agreement with COSMIC data between 8 km and 35 km.…”

Section: Introductionmentioning

confidence: 99%

Diurnal tides from the troposphere to the lower mesosphere as deduced from TIMED/SABER satellite data and six global reanalysis data sets

Sakazaki¹,

Fujiwara²,

Zhang³

et al. 2012

J. Geophys. Res.

Self Cite

View full text Add to dashboard Cite

We compare and examine diurnal temperature tides including their migrating component (DW1) from the troposphere to the lower mesosphere, using data from Thermosphere-Ionosphere-Mesosphere-Energetics and Dynamics/Sounding of the Atmosphere using Broadband Emission Radiometry (TIMED/SABER) and from six different reanalysis data sets: (1) the Modern Era Retrospective analysis for Research and Applications (MERRA), (2) the European Centre for Medium-range Weather Forecasts (ECMWF) reanalysis (ERA-Interim) (3) the National Centers for Environmental Prediction (NCEP) Climate Forecast System Reanalysis (CFSR), (4) the Japanese 25-year reanalysis by Japanese Meteorological Agency (JMA) and the Central Research Institute of Electric Power Industry (CRIEPI) (JRA25), (5) the NCEP/National Center for Atmospheric Research reanalysis (NCEP1), and (6) the NCEP and Department of Energy (DOE) Atmospheric Model Intercomparison Project (AMIP-II) reanalysis data (NCEP2). The horizontal and vertical structures of the diurnal tides in SABER and reanalyses reasonably agree, although the amplitudes are up to 30-50% smaller in the reanalyses than in the SABER in the upper stratosphere to lower mesosphere. Of all tidal components, the DW1 is dominant while a clear eastward propagating zonal wave number 3 component (DE3) is observed at midlatitudes of the Southern Hemisphere in winter. Among the six reanalyses, MERRA, ERA-Interim and CFSR are better at reproducing realistic diurnal tides. It is found that the diurnal tides extracted from SABER data in the winter-hemisphere stratosphere suffer from sampling issues that are caused by short-term variations of the background temperature. In addition, the GSWM underestimates the amplitude in the midlatitude upper stratosphere by about 50%

show abstract

“…If the hydrostatic assumption is true for surface pressure, tidal winds do not blow at Earth's surface, but at high altitudes. Tidal lunar variation of the horizontal wind have been indeed reported in the mesosphere (above 50 km) [ Sandford et al , ], in the stratosphere [ Nastrom and Belmont , ; Sakazaki et al , ], in the upper troposphere [ Krahenbuhl et al , ], but never in the low troposphere. So tidal winds do not produce any notable friction torque.…”

Section: Hydrostatic Model Of the Tidal O1 Oscillation Of The Pressurmentioning

confidence: 99%

Lunar influence on equatorial atmospheric angular momentum

2014

View full text Add to dashboard Cite

This study investigates the relationship between the equatorial atmospheric angular momentum oscillation in the nonrotating frame and the quasi-diurnal lunar tidal potential. Between 2 and 30 days, the corresponding equatorial component, called Celestial Atmospheric Angular Momentum (CEAM), is mostly constituted of prograde circular motions, especially of a harmonic at 13.66 days, a sidelobe at 13.63 days, and of a weekly broadband variation. A simple equilibrium tide model explains the 13.66 day pressure term as a result of the O 1 lunar tide. The powerful episodic fluctuations between 5 and 8 days possibly reflect an atmospheric normal mode excited by the tidal waves Q 1 (6.86 days) and 1 (7.095 days). The lunar tidal influence on the spectral band from 2 to 30 days is confirmed by two specific features, not occurring for seasonal band dominated by the solar thermal effect. First, Northern and Southern Hemispheres contribute equally and synchronously to the CEAM wind term. Second, the pressure and wind terms are proportional, which follows from angular momentum budget considerations where the topographic and friction torques on the solid Earth are much smaller than the one resulting from the equatorial bulge. Such a configuration is expected for the case of tidally induced circulation, where the surface pressure variation is tesseral and cannot contribute to the topographic torque, and tidal winds blow only at high altitudes. The likely effects of the lunar-driven atmospheric circulation on Earth's nutation are estimated and discussed in light of the present-day capabilities of space geodetic techniques.

show abstract

Diurnal variations of upper tropospheric and lower stratospheric winds over Japan as revealed with middle and upper atmosphere radar (34.85°N, 136.10°E) and five reanalysis data sets

Cited by 5 publications

References 47 publications

WHU VHF radar observations of the diurnal tide and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N), China

WHU VHF radar observations of the diurnal tide and its variability in the lower atmosphere over Chongyang (114.14° E, 29.53° N), China

Diurnal tides from the troposphere to the lower mesosphere as deduced from TIMED/SABER satellite data and six global reanalysis data sets

Lunar influence on equatorial atmospheric angular momentum

Contact Info

Product

Resources

About