Daily zonal wind data of the four pre-MAP-winters 1978/79 to 1981/82 obtained over Central Europe and Eastern Europe by the radar meteor method were studied. Available temperature and satellite radiance data of the middle and upper stratosphere were used for comparison, as well as wind data from Canada. The existence or nonexistence of coupling between the observed large scale zonal wind disturbances in the upper mesopause region (90 to 100 km) and corresponding events in the stratosphere are discussed

Greisiger, K. M.

Lysenko, I. A.

Portnyagin, Y. I.

English

NASA Technical Reports Server

. i " g85-20467
L&RGE-SCALEWINTER-TIHZ DIST_RIt.A._CESIN I_'_EOI WINDS O"?E_
CI:_TZAL At,tOEAsrrJ_ EUROPE
K. H. Creisiger
Central Institute of Solar-Terrestrial Physics
Observatory of Ionosphere Research
, DDR-2565, Kuhlungsborn. GD_
¥u. I. Portnyagln and I. A. Lysenko
USSR State Comittee of liydro=eteoroloRy and Envlrot_ental Control
Institute of Experir_ental Meteorology
Obninsk, USSR
As it is well known, in winter a predominant vesterly circulation exists in
middle and high latitudes from the stratosphere up to the mesopause region _80-
100 km), driven by the stratospheric polar west wind vortex. Sudden strato-
spheric wamtngs lead to disturbances or even to a breakdown of this vortex with
- occurrence of easterly winds (LABITZEE. 1981). Such large-scale circulation
disturbances can be 0sen in pressure maps up to metospheric heights (IIAUJOKAT et
al.. 1983). }_reover, in the mesopsuse region similar circulation disturbances
in periods with stratospheric warnings are also knotra for a long tim from
taeteor wind and ionospheric drift results (PORTNYAGII! and SPRII_GER. 1978). In
the present report we investigate daily zonal wind data of the four Pre-FAP-
winters 1978179 to 1981182 obtained over Central Europe (station Kuhlungsboro,
54.1*N/II.B'E) and Eastern Europe (state Obninsk. 55"NI38"E) by the radar meteor
method (D2). Available t(nperature end satellite radiance data of the middle 4
and upper stratosphere are used for cooparison, an yell as wind &its from Canada
.... (SHITH et al., 1982). The existence or non-existence of coupling betwee'a the
• "'° observed large-scale zonal wind disturbances in the upper mesopause region (90-
100 Inn) and corresponding events in the stratosphere it discussed.
i " An anslysis of wind disturbances in khe 90-100 Inn level above Central
Europe in the first Pre-HAP--vinter 1978179 has been already published on the
basis of 02 wind results of the station Kuhiungsborn and ionospheric drift (Ol)
l results of the station Colin (GREISIGER et al., 1979). These results will be
• st.-.-_=arized here only with inclusion of D2 wind data frota the station OLminsk in
Eastern Europe. An sb.o_m in Figure I in January and February 1979 three
i distinct large scale reversals of the xonaI prevailing wind (V) in 90-100 I_ "--took place as t_entured bY the D2-_ethod at guhitmgsborn nnd Obn°insk as well as
• " " " ' " ' by the Dl--t=ethod at ColLm (3-days running means are used for smoothing, applied
to all winters). In the stratosphere an intense warming of the polar regionstarted after 21 January, proceeding in three pulses and leading to a total
breakdown of the circLtnpolar vortex ('Major stratospheric wsr_ing") on 23
February (LABITZKE. 1979). The three wind reversals st 95 k:= occurred so._e days
in advance of the peaks of tile wnrvi__._ pulses at the 4 mbar level (S_J Ch 26
data), which in turn occur a l':ttle earlier than the peaks in lO -.bar tempera-
ture above the l_orth Pole (of. Figure 1). Xhe period of strongest East wind in
the 90-100 kta level around 25 February coincided rather well with the breskdotrn
of the Polar vortex in the stratosphere, suggesting a strong coupling between
the stratosphere and the =esopause region during this t_ajor stratospheric
warming event.
€
As reported by SHITI1 et al. (1982), the zonal circulation in the ,-esosphere
L and menopause region in this winter above Canada, observed at Ssskatoon (52"N,
104*W) by the Dl-_ethod (partial reflection), did not show a close coupling.
There was no reversal near 25 February. Such different beh_viour on large
scale, however, can be understood throut:h the longitudinal as)aazaetry in the
I
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'
https://ntrs.nasa.gov/search.jsp?R=19850012157 2020-03-22T18:37:37+00:00Z
vertical propagation of planetary raves, _hich very probably are the prltutry
cause of th_ coupling.
/ In rinser 19791g0 several circulation disturbances took place again as seen
in the zonal prevailing rind data V° of Obnins_ and Euhlungsborn (Figure 2).
f For comparison the situation in the stratosphere is characterized in Figure 2 by
the tmperature of the IO nbar level end satellite IR radiance data of 4 and 1.7
mbar ver the llorth Pole (LAEITZKE et l., 1980). Fro_ 10 January up to 20
[_ February 1980 in the upper stratosphere (4 and 1.7 =bar level) several '_inOr
_armings" occurred, vhereaa in the _iddle stratosphere (lO =bar) the t_perature
. above the l_orth Pole vas nearly equal or lover than the long-tens _e_ values
(Figure 2). A_ 9_ P_ rind reversals _erc observed above Central and Eastern
Europe around 12 and 24 January folloved by a recovery of the Nest rind circula-
tion sod a nov veskening after 10 Fehruary. Sianultaneous Dl-_aind _easurc_ents
t Sasks:oon also shov sever l.rind disturbanc s but not uith such s clot_
| to_t_ral connection as for the European region. The =esopause region above
Europe setnasfavorable to indicate large scale _inter-time disturbances of the
pressure field and corresponding _ind tield, as already sho_n lor the major
stratvsrm effect in the first Pre-HAP-vinter. At the end of February a '_sjor
varming" of the vhole stratosphere took places as seen in Figure 2 by sharp
i peaks of the radiances _nd the t_perature above the Pole. The zonal rind in
the =esopau_e region nov _ertas to be disturbed simultaneously over the vhole
Northern Itemitphere vlth East rinds over Europe (Obninsk, Figure 2) and also
above Canada around 29 February.
z _ In the third Pre-_P-uinter 1980/81, the stratosphere showed an extreme
behsviour (LABITZKE et al., 1981). _eglnning vith the end of I;ov_ber, strong
cooling took place in the polar middle _tratosphere, reaching temperatures in
Decmber end in the first half of January substantially below the long-ten_ =e_n
; values, as shams in Figure 3 for the IO mbar level. By the end of January a
, sudden and very etrong running began first in the upper polar stratosphere and s
few days later in the 10 mbar loyal (of. Figure 3). $o the rinser 19E0181 in
the _tratosphere can be clearly divided into tvo psrt_, viz., a quiet period up
to 20 January _nd a highly disturbed period after 20 January. In the uesopause
t
f_!''
(
- !
(
93
l : tg_ _v t£C JAn rlv _
i _ ._ zooa_P'_'"'J"'"V_ f,,m]
G ._ f : A . I , _ .._ ._.,m 2_'
. . _.....vz,o_,_-_-_._,.-,,..,_
. . ,,,_,
s lNm,t'.*ra._ a"d , v i K * _3
I m-t,,_e . R _ _ ; A,; _,_'/,,Yt .'', I, ,,:i_/\ _.|lr,\ ,v
'_ _,..""_: l,_x , i V " I _ \ " _
/-k, '_4 , j ,_ :
•, ,r A ^,,/ , .o
• _ _,_ i "klk [ 2,, _ / rr_- ._
.... ] ...... l . ..., .
tYZ# _ #/'C ..wv f£B _ t_
t
! Figure 2. :
!
•
region, as could be expected fro= earlier wiuter_, the tonal vi_d in this second I
. past of the winter vas alto very disturbed.
During the v.azimu: of the stratospheric warming at the end of Jmauary/
' beginning of February 1981 the strong zonal westerlies at 9.$ k_ decreased
rapidly and reversed to East wind, practically simultaneously above Central and
; Eastern Europe (Figure 3), and also above Canada. This confirms the large-scale
character of the disturbance cod the close coupling with the stratospheric _-
i vat:Sag ev(mt. The fir.t part of the winter 19_O181. though rather quiet with . •
extremely low tt_per'atures iu the polar stratosphere _hoved several disturbances
o£ the zorml wind in the t_escpause region, not lets intense as during the _tjor
stratospheric war=Sag. As skown in Figure 3, ait_ulttmenus reversals to East
wind above Central and Eastern Europe occur in l;ove_aber _nd Decrtaber, sad a
rapid weakening o£ the _est wind shortly before 20 J_nuary. £ven stronger
di=turbances with revereals were observed at Saskatoon at 93 k_ at about the
sa._e periods. That t:esaa that in the first part of the winter 1980181 the zonal
circulation in the t_enopau_e region is highly disturbed in a large-scale t:anner,
though the polar stratosphere was rather quiet. One csa conclude that the_e
disturbances are probably connected with processes in the t_esosphere or in the
_egopause region itself. Soce indication we hgve fro= the radiance data (Figure
, 3), which show trot: Itove_',*r to January to_e little warming peaks which are
higher at 1.7 tabar (44 k_) than at 4 tabar (38 k=).
In January and beginning of February 1981. re=arknble vnve-llke variations
! o1 the zorml wind at 9_ k_ with large e_plitudes, very similar at both vtationa,
, Yarn observed. Xhey ,era to be connected with corresponding variations o£ the
"'" I "
dominant stationary planetary temperature wave TI in the stratosphere at 60*N
(cf. Figure 3). In this respect the stratospherxc temperature field was
disturbed already before the major warning event (_._plification o_ wave I as a
precondition of a major stratospheric war_ing, LABITZKE (1981), and an influence _.
• _ . . ,up to, t_e 95 km level at medi_ latitudes se_a to exist.
The fourth Pre-HAP--_inter 1981/82 is in some respecte similar to the second
on_. In mid-December a wa_ing in the upper stratosphere (4 and 1.7 mbar) with
' simultaneous cooling in the middle end lower stratosphere was observed (NAUJOKAT
et al., 1982) (cf. Figure 4). The zonal wind at 95 k= over Europe is strongly
! disturbed in December with values below the long-term mean values and some short
periods of East winds. In Jnnuary in the polar stratosphere a strong '_inor
warming" occurred (NAUJOKAT et al.. 1982) with two pulses in the radiances (1.7
and 4 mbar) and 10 mbsr t_pcrature around I0 and 25 January (Figure 4). In
coincidence with the stronger second pulse we observe an almost simultaneous
revereal of the zon_l wind above Central and Eastern Europe with _n East wind
period up to the beginning of February. At Saskatoon at the _me time a
reversal down to 62 _ was recorded which shows the large-scale character of
thie wind disturbance in connection with the strong '_inor warming". !
[
• . SN--m_ri_in_ our r._ult$ one c_n say that in winter during '_ajor warmings"
owzousty a c_o.e couptzng exists betwe_m the stratoepnere and the _esopanse
region. The temporal and spatial relation betvecn the event_ in both
atmospheric layers can be understood only with informations about the vertical i
_ propagation of the pertinent planetary waves as a primary cause of the coupling. ;.
, I
/ ! 1
k . /
f'_ {............
t
95
_81 _V DEC j.4N t£8 _ ts_
i _ l 6 e , - • • i i i
v._. /N. j _s,.,[-IsJ_.
1 o- - v k..._
m_ I
I Strams_er_c
_: dl_- ICmlX_Tt_rean_ I
i.... ra_r_eJ , ' 1' V "_''_1
""_r
_. r l'cJ
'-40 _
"_" _'_ t_m _ ._
l_O! _v DEC da_ rgB _a_ n_?
f
Figure 4.
l_ot much less in_ense large-scale zonal wind disturbances in the r-enopause
region were obnerved during l,_riods of relatively quiet or even extremely "
; typical winter condition_ in the vtratosphere. The cause of these disturbances
io not clear; it has probably to be sought in the mesosphere or in the mesopause
region itself.i
REFER_ICES
Gre£siger, K. H; et al. (1979), Phys. Solnr_terr., Potsdam, lOn, 107.
Labitzke, K. (1979), Progress Report for PHP-I.
Labitzke, K. et al. (1980), Beilage Berliner 14etterkarce 49/E0. SO 9/80.
Labitzke, g. et al. (1981), Beilage Berliner Netterkarte 81/81, SO 13181.
Labitzke, K. (1981), Hon. Wea. Rev., I__09, 983.
Naujokat, B. et al. (1982), Upp. Attn. Prngr. gull., Spec. Issue. 8_2-2, August.
Naujokat, B. et al. (1983), Beilage Berliner t/etterkarte 57183, SO 13183.
Poztnyagln, Yu. I. and K. Sprenger (editorn) (1978), Nind Hearurements at
HeiKhts of 90-100 km_b_ Ground-Based Hethods (in Russian), Gidremeteaizdat
Leningrad.
Smith, H. d. ctal. (1982), Paper fla.C.3.2.2, presented at COSPAR Gen.
• Assembly, Ottawa.


Large Scale Winter Time Disturbances in Meteor Winds over Central and Eastern Europe

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