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Resonant transient atmospheric waves—A possible mechanism of connection between lower atmosphere, stratosphere and mesosphere
Pergamon
Adv. Space&s. Voi. 20, No. 6, pp. 1227-1231, 1997 91997 COSPAR. Published by Elsevier Science Ltd. At1rights reserved Printed in Great Britain 0273-l 177/97$17.00 + 0.08 PII: so273-1177(9~77~X
RESONANT TRANSIENT ATMOSPHERIC WAVES-A POSSIBLE MECHANISM OF CONNECTION BETWEEN LOWER ATMOSPHERE, STRATOSPHERE AND MESOSPHERE A. A. Krivolutsky*
and M.-L. Char&**
~~e~~ral Aerological U~se~~o~, ~ora~o~ of ~america~ ~odel~i~g, ~e~o~s~a 3,141700 ~olgop~dn~, Moscow Region, Rtsssia **Service &Aeronomie, CNRS, BP 3-91371, Verrieres-le-B&son, France
ABSTRACT 2-D model runs based on numerical quasigeostrophic transient wave’s model has revealed the possibility of the middle atmosphere (MA) resonant excitation as a whole for ~ecial(r~onant) periods of a periodical external forcing. The reaction of the MA looks like large-scale transient waves (Rossby waves) and depends on a zonal-mean wind structure,zonal wavenumber and the structure of source. Such transient waves excited at lower boundary penetrate to mesospheric levels. The periodogram analysis of temperature lidar data for Haute Provance has shown the characteristic dominant periods (5-7, and 9-12 days) between 30-80 km for winter 1993, and with vertical structure similar to numerical 0 1997 COSPAR. Published by Elsevier Science Ltd. simulation results. INTRODUCTION It is well-known that an important part of the dynamics of the MA are wavelike structures of planetary scale. These disturbances can be described in terms of so-called external Rossby waves. Detail review on travelling waves was given by Salby (1981). The travelling components in the stratosphere have been detected by means of satellite borne instruments. theoretical results (Hirota and These investigations are in general agreement with Hirooka,I984). Using a harmonic analysis (based on least squares technique) of rocket mesurements, Bittner et al. (1994) found peculiar structures in the vertical distribution of amplitudes and phases, indicating the presence of so-called ‘quiet atmospheric layers’ with variations that were minimum at the layer altitude and were anticorrelated below and above these layers. The possibility of excitation of transient waves in the MA was discussed by Krivolutsky (1989) , Krivolutsky and Kiryushov (1992) in relation to 27-day waves, by Schoeberl and Clark (1980) and Madden and Julian (1972) in relation to S-day waves. It is the purpose of this work to investigate the correspondence between the vertical structure of temp~at~e oscillations generated by 2-D model runs for resonant periods and revealed by periodogram analysis of lidar data. 2-D MODELLING Numerical modelling based on linear assumptions is a good instrument for MA dynamics study. Schoeberl and Clark (1980) used a similar model to analyse the possibility of S-day wave penetration from below to the higher levels. The present model calculations used a periodic source at a lower boundary. t227
A. A. Krivolutsky and M.-L. Chanin
1228 80 75
i. _z 2 3
60 55
-50
/_
9.. 4
9
,
/
14
19
:
24
29
1_.--J__.
34
39
LATIT~I~ Fig. 1.
44
1
I
49
54
I
/
59
64
!
6;
74.
!/
79
84
(XHEM-RE)
Spatial structure of geopotencial perturbations (dgm) for 9-Gay wave induced at lower boundary (2-D model runs, m=l)
80 .7E, 70
i I
4
Fig. 2.
I
i
9 . 14 19 24 29 34 39 44 49 54 59 64 69 74 79 84
LATITUDE(N.HEM-RE)
Spatial structure of temperature perturbations (degrees) for 9- 1O-day wave induced at lower boundary ( 2-D model runs , m=l )
1229
Fig. 3.
Periodogram analysis results oflidar data (Haute Provance ,44W, France, Janus-Feb~~, 1993)
T (deg) Fig. 4.
Vertical structure of 9-day wave temperature oscillations 2-D model runs , m= 1: 44*N) ( .. . ..... .. lidar data. H. Provance ; _
A. A, Krivolutsky and M.-L. Chanin
1230
Model (brief descrintion) The 2-D model is based on the quasigeostrophic vorticity equation, the energy equation and the continuity equation. Then the second-order differential equation for stream function was solved using numerical scheme of Madala (1978). The lower boundary was placed at 5 km level and the upper boundary was at 80 km from equator to pole. The vertical velocity in the wave was equal to zero at the upper boundary and was periodically disturbed at lower boundary. A vertical grid distance was about 2.5 km and meridional grid distance was about 1.8 deg. The Newtonean cooling and Rayieigh friction were used as factors of dissipation. The model permits to excite the MA by a source placed inside the area of integration. Such scenario is important for solar periodicity effects study. Results of model calculations Climatological winter zonal mean wind (CIRA 86) was used in model calculations and the results has revealed the resonant peak near 9-10 days period for zonal wave number m=l . The amplitude of periodical disturbances was equal to 1 gpm as a lower boundary condition. The geopotencial wave for winter Northen Hemispheric conditions (determined by zonal wind) looks like as shown in Figure 1. The amplitude of the wave increases with height, reaching its maximum near 50 km level. The maximum of the source at lower boundary was centred near 60”N. In spite of this fact the maximum of the wave near 50 km is plased near 50”N possibly due to refraction effect. Then a spatial structure of temperature wave was calculated using connection between geopotencial heghts and temperature values : ag_RT az
H
where $ - geopotencial perturbation, T - temperature perturbation, R - gas constant. Figure 2 shows the corresponding field of the temperature wave (m=l). It is nessary to pay attention to the existance of two maxima in vertical structure which are in antiphase with a structure of the geopotencial perturbations and one can notice that the minimum of T (‘quiet layer’) is near the 4 maximum in accordance with correlation between these values mentioned above. LIDAR DATA ANALYSYS Vertical temperature lidar profiles for 30 - 80 km (winter 1993, obs. Haute Provance, France) were used to investigate the real temperature oscillations in the MA and to reveal their dominant periods. Lidar technique permits to realize mesurements at night when clouds are absent (spline-interpolation procedure was used for cloudy nights to fill in the missing dates). The parabolic trend for time data sets was expelled before periodogram analysis. Figure 3 shows the results of periodogram analysis for different levels. There are two spectral peaks as one can see in the Figure 3 - near 5-7 and 9-12 days. It is necessary to mention that only 24 lidar profiles were used really comprising 1.5 month (inside January - February 1993 interval). We can see also temperature perturbations minimum near 50 km level (Figure 4) for the 9 - 10 day period of oscillations and two maxima near 40 km and 70 km.
Winter Mesopause Wind Field
1231
DISCUSSION AND CONCLUSIONS The results of 2-D model calculations based on numerical model and lidar data periodogram analysis of vertical temperatu~ profiles have revealed similar periods of the wave (near 9-l 2 days) supporting the idea of a MA resonant forcing from the troposphere. These transient waves penetrate to the mesospherics levels and possibly disturb lower ionosphere inside the D-region. So-called ‘quiet layers ’ in temperature osciflations correspond exactly to the maxima of geopotencial waves perturbation in accordance to hydrodynamic correlations. REFERENCES Hirota, I., and T. Hirooka, Normal mode Rossby waves in the upper stratosphere, I,: First symmetric modes of wavenumber 1 and 2, J. Atmos. Sci., 41, 1253-1267, (1984). Krivolutsky, A. A., Atmospheric planetary waves induced by solar rotation, Handbook for MAP, 29, 86-91, (1989). Krivolutsky, A. A., and B. M. Kiryushov, The 2-D numerical modelling of the dynamical input for the middle atmosphere due to solar 27-day variability. Assembly of EGS, ST5, Edinb~~, UK, report, (1992). Madala, R. V., An efficient direct solver method for separable and non separable elliptic eguations, Mon. Wea. Rev., 106, 1735-1741, (1978). Madden, A. R. and P. R. Julian, Further evidance of global scale S-day pressure waves, J. Atmos. Sci., 29, 14641469, (1972). Bittner M., D. Offermann, I. V. Bugaeva, G. A. Kokin, Y. P. Koshelkov, A. A. Krivolutsky, D. A. Tarasenko, M. Gil-Ojeda, A. Hauchecorne, F.-L. Lubken, B. A. De La Morena, A. Mourier, H, Nakane, K. I. Oyama, F. J. Schmidlin, I. Soule, L. Thomas and T. Tsuda, Long period/large scale oscillations of temperature during the DYANA campaign, J. Atmos. Terr. Phys., 49, 16751700, (1994). Salby, M. L., Rossby normal modes in nonuniform background configurations. Part I: Simple Fields, J. Atmos. Sci., 38, 1803-1826, (1981). Shoeberl, M. R. and J. H. Clark, Resonant planetary waves in a spherical atmosphere, J. Atmos. Sci., 37, 20-28 , (1980).
JASR20:.5-E
Adv. Space&s. Voi. 20, No. 6, pp. 1227-1231, 1997 91997 COSPAR. Published by Elsevier Science Ltd. At1rights reserved Printed in Great Britain 0273-l 177/97$17.00 + 0.08 PII: so273-1177(9~77~X
RESONANT TRANSIENT ATMOSPHERIC WAVES-A POSSIBLE MECHANISM OF CONNECTION BETWEEN LOWER ATMOSPHERE, STRATOSPHERE AND MESOSPHERE A. A. Krivolutsky*
and M.-L. Char&**
~~e~~ral Aerological U~se~~o~, ~ora~o~ of ~america~ ~odel~i~g, ~e~o~s~a 3,141700 ~olgop~dn~, Moscow Region, Rtsssia **Service &Aeronomie, CNRS, BP 3-91371, Verrieres-le-B&son, France
ABSTRACT 2-D model runs based on numerical quasigeostrophic transient wave’s model has revealed the possibility of the middle atmosphere (MA) resonant excitation as a whole for ~ecial(r~onant) periods of a periodical external forcing. The reaction of the MA looks like large-scale transient waves (Rossby waves) and depends on a zonal-mean wind structure,zonal wavenumber and the structure of source. Such transient waves excited at lower boundary penetrate to mesospheric levels. The periodogram analysis of temperature lidar data for Haute Provance has shown the characteristic dominant periods (5-7, and 9-12 days) between 30-80 km for winter 1993, and with vertical structure similar to numerical 0 1997 COSPAR. Published by Elsevier Science Ltd. simulation results. INTRODUCTION It is well-known that an important part of the dynamics of the MA are wavelike structures of planetary scale. These disturbances can be described in terms of so-called external Rossby waves. Detail review on travelling waves was given by Salby (1981). The travelling components in the stratosphere have been detected by means of satellite borne instruments. theoretical results (Hirota and These investigations are in general agreement with Hirooka,I984). Using a harmonic analysis (based on least squares technique) of rocket mesurements, Bittner et al. (1994) found peculiar structures in the vertical distribution of amplitudes and phases, indicating the presence of so-called ‘quiet atmospheric layers’ with variations that were minimum at the layer altitude and were anticorrelated below and above these layers. The possibility of excitation of transient waves in the MA was discussed by Krivolutsky (1989) , Krivolutsky and Kiryushov (1992) in relation to 27-day waves, by Schoeberl and Clark (1980) and Madden and Julian (1972) in relation to S-day waves. It is the purpose of this work to investigate the correspondence between the vertical structure of temp~at~e oscillations generated by 2-D model runs for resonant periods and revealed by periodogram analysis of lidar data. 2-D MODELLING Numerical modelling based on linear assumptions is a good instrument for MA dynamics study. Schoeberl and Clark (1980) used a similar model to analyse the possibility of S-day wave penetration from below to the higher levels. The present model calculations used a periodic source at a lower boundary. t227
A. A. Krivolutsky and M.-L. Chanin
1228 80 75
i. _z 2 3
60 55
-50
/_
9.. 4
9
,
/
14
19
:
24
29
1_.--J__.
34
39
LATIT~I~ Fig. 1.
44
1
I
49
54
I
/
59
64
!
6;
74.
!/
79
84
(XHEM-RE)
Spatial structure of geopotencial perturbations (dgm) for 9-Gay wave induced at lower boundary (2-D model runs, m=l)
80 .7E, 70
i I
4
Fig. 2.
I
i
9 . 14 19 24 29 34 39 44 49 54 59 64 69 74 79 84
LATITUDE(N.HEM-RE)
Spatial structure of temperature perturbations (degrees) for 9- 1O-day wave induced at lower boundary ( 2-D model runs , m=l )
1229
Fig. 3.
Periodogram analysis results oflidar data (Haute Provance ,44W, France, Janus-Feb~~, 1993)
T (deg) Fig. 4.
Vertical structure of 9-day wave temperature oscillations 2-D model runs , m= 1: 44*N) ( .. . ..... .. lidar data. H. Provance ; _
A. A, Krivolutsky and M.-L. Chanin
1230
Model (brief descrintion) The 2-D model is based on the quasigeostrophic vorticity equation, the energy equation and the continuity equation. Then the second-order differential equation for stream function was solved using numerical scheme of Madala (1978). The lower boundary was placed at 5 km level and the upper boundary was at 80 km from equator to pole. The vertical velocity in the wave was equal to zero at the upper boundary and was periodically disturbed at lower boundary. A vertical grid distance was about 2.5 km and meridional grid distance was about 1.8 deg. The Newtonean cooling and Rayieigh friction were used as factors of dissipation. The model permits to excite the MA by a source placed inside the area of integration. Such scenario is important for solar periodicity effects study. Results of model calculations Climatological winter zonal mean wind (CIRA 86) was used in model calculations and the results has revealed the resonant peak near 9-10 days period for zonal wave number m=l . The amplitude of periodical disturbances was equal to 1 gpm as a lower boundary condition. The geopotencial wave for winter Northen Hemispheric conditions (determined by zonal wind) looks like as shown in Figure 1. The amplitude of the wave increases with height, reaching its maximum near 50 km level. The maximum of the source at lower boundary was centred near 60”N. In spite of this fact the maximum of the wave near 50 km is plased near 50”N possibly due to refraction effect. Then a spatial structure of temperature wave was calculated using connection between geopotencial heghts and temperature values : ag_RT az
H
where $ - geopotencial perturbation, T - temperature perturbation, R - gas constant. Figure 2 shows the corresponding field of the temperature wave (m=l). It is nessary to pay attention to the existance of two maxima in vertical structure which are in antiphase with a structure of the geopotencial perturbations and one can notice that the minimum of T (‘quiet layer’) is near the 4 maximum in accordance with correlation between these values mentioned above. LIDAR DATA ANALYSYS Vertical temperature lidar profiles for 30 - 80 km (winter 1993, obs. Haute Provance, France) were used to investigate the real temperature oscillations in the MA and to reveal their dominant periods. Lidar technique permits to realize mesurements at night when clouds are absent (spline-interpolation procedure was used for cloudy nights to fill in the missing dates). The parabolic trend for time data sets was expelled before periodogram analysis. Figure 3 shows the results of periodogram analysis for different levels. There are two spectral peaks as one can see in the Figure 3 - near 5-7 and 9-12 days. It is necessary to mention that only 24 lidar profiles were used really comprising 1.5 month (inside January - February 1993 interval). We can see also temperature perturbations minimum near 50 km level (Figure 4) for the 9 - 10 day period of oscillations and two maxima near 40 km and 70 km.
Winter Mesopause Wind Field
1231
DISCUSSION AND CONCLUSIONS The results of 2-D model calculations based on numerical model and lidar data periodogram analysis of vertical temperatu~ profiles have revealed similar periods of the wave (near 9-l 2 days) supporting the idea of a MA resonant forcing from the troposphere. These transient waves penetrate to the mesospherics levels and possibly disturb lower ionosphere inside the D-region. So-called ‘quiet layers ’ in temperature osciflations correspond exactly to the maxima of geopotencial waves perturbation in accordance to hydrodynamic correlations. REFERENCES Hirota, I., and T. Hirooka, Normal mode Rossby waves in the upper stratosphere, I,: First symmetric modes of wavenumber 1 and 2, J. Atmos. Sci., 41, 1253-1267, (1984). Krivolutsky, A. A., Atmospheric planetary waves induced by solar rotation, Handbook for MAP, 29, 86-91, (1989). Krivolutsky, A. A., and B. M. Kiryushov, The 2-D numerical modelling of the dynamical input for the middle atmosphere due to solar 27-day variability. Assembly of EGS, ST5, Edinb~~, UK, report, (1992). Madala, R. V., An efficient direct solver method for separable and non separable elliptic eguations, Mon. Wea. Rev., 106, 1735-1741, (1978). Madden, A. R. and P. R. Julian, Further evidance of global scale S-day pressure waves, J. Atmos. Sci., 29, 14641469, (1972). Bittner M., D. Offermann, I. V. Bugaeva, G. A. Kokin, Y. P. Koshelkov, A. A. Krivolutsky, D. A. Tarasenko, M. Gil-Ojeda, A. Hauchecorne, F.-L. Lubken, B. A. De La Morena, A. Mourier, H, Nakane, K. I. Oyama, F. J. Schmidlin, I. Soule, L. Thomas and T. Tsuda, Long period/large scale oscillations of temperature during the DYANA campaign, J. Atmos. Terr. Phys., 49, 16751700, (1994). Salby, M. L., Rossby normal modes in nonuniform background configurations. Part I: Simple Fields, J. Atmos. Sci., 38, 1803-1826, (1981). Shoeberl, M. R. and J. H. Clark, Resonant planetary waves in a spherical atmosphere, J. Atmos. Sci., 37, 20-28 , (1980).
JASR20:.5-E