Ocean’s Role in the Stratosphere-Troposphere Interaction Yulia A. Zyulyaeva Moscow State University P.P.Shirshov Institute of Oceanology, RAS, Moscow 1/17

2/17 Stratosphere 11-year solar cycle Troposphere Polar Night Jet Planetary Waves QBO

Eliassen-Palm Flux – capturing the impact of planetary waves onto the mean flow As proposed by Eliassen and Palm (1961) 1 As proposed by Plumb (1985) 2 If zonal averages are taken reduces to the 1) Eliassen, A. and E. Palm,1961: On the transfer of energy in stationary mountain waves. Geofys. Publ., No. 3, ) Plumb, R.A., 1985: On the three-dimensional propagation of stationary waves. J. Atmos. Sci., 42, /17 Wind deceleration is found to be large in the neighborhood of large negative values of divergence1

Monthly mean From NCEP/NCAR Reanlaysis datasets Geopotential heights, Air temperature, Wind From Met Office Hadley Centre observations datasets SST We analyze 49 Winter Seasons : November – March 1958/1959 – 2010/2011 Used Data 4/17

3D Eliassen-Palm Flux at 30hPa 5/17 Arrows - horizontal component, contours - vertical x10 -5 m 2 /s 2 December 1975 December 1976 Before SSW (major event) in January 1977

Climatology 49-year mean z-component of the EP Flux December January February March (x10 -5 m 2 /s 2 ) Negative values 6/17

EP z -Flux and U-wind anomalies for 30hPa December – January 1 month lag PRECONDITIONS 1 st EOF for U 30 46% PNJ 1 st EOF for F z 43% 7/17 Correlation -0,58 PC for U30 with the opposite sign

8/17 NovDecJanFebMar Nov Dec Jan Feb Mar EP z -Flux and U-wind anomalies U-wind 30hPa Correlation coefficient: PC of the 1st EOF of EP-flux (z-component) and PC of the 1st EOF of zonal wind at 30hPa EP z 30hPa 1.Karpetchko A., and G. Nikulin, Influence of early winter upward wave activity flux on midwinter circulation in the stratosphere and troposphere, J. Climate, 2004, vol. 17, pp Holton, J.R., Mass, C, Stratospheric vacillation cycles, Journal of Atmospheric Sciences, 33,

Correlation Coefficient between Fz (60N, 45W) and UWND at 30hPa 9/17 January February

10/17 Zyulyaeva, Yu.A., Jadin, E.A., Analysis of three - dimensional Elliassen-Palm fluxes in the lower stratosphere, Russian Meteorology and Hydrology, in press Scheme of the upward and downward propagation

11/17 Scheme of the upward and downward propagation Zyulyaeva, Yu.A., Jadin, E.A., Analysis of three - dimensional Elliassen-Palm fluxes in the lower stratosphere, Russian Meteorology and Hydrology

12/17 -0,58 -0,72 -0,57 -0,26 Break of the “preconditions” PCs for the 1 st EOF of EP z -Flux for December and U-wind for January

Correlation Coefficient between QBO 30hPa (UWND 2.5N, 102.5E) and UWND 30hPa for period (January - January) 95% West (East) QBO > Strong (weak) PV in the Arctic Holton, J.R., Tan, H.C., The influence of the equatorial quasi - biennial oscillation on the global circulation at 50 mb, Journal of Atmospheric Sciences, 37, /17

1947 – 1976 “COOL PDO” 1977 – mid-1990’s “WARM PDO” 14/17

The Pacific Decadal Oscillation 1 st EOF for SST 15/17 PCs for the 1 st EOF of SST

Relations between EP z -Flux and SST anomalies December - December 1 st EOF for F z PCs for the 1 st EOF of SST and F z 16/17 0,650,62 0,11 1 st EOF for SST Evgeny A. Jadin, Ke Wei, Yulia A. Zyulyaeva, Wen Chen, Lin Wang, Stratospheric wave activity and the Pacific Decadal Oscillation, Journal of Atmospheric and Solar-Terrestrial Physics 72 (2010) 1163–1170

Conclusions (1) 1.3D EP-Flux shows significant longitudinal asymmetry 2.Strong/weak penetration of planetary waves into the stratosphere in December precedes to the major SSW/Ex. Cold events in January 3.No significant trends of 3D EP-Fluxes were indicated during the wintertime (not shown) 17/17

1.The mechanism connected with the thermal excitation of planetary waves by the SST anomalies in the North Pacific in the early winter and a downward propagation in the late winter in the North Atlantic region (“stratospheric bridge”) is proposed 2.Are there relations between the SSTs in the North Pacific and North Atlantic and the stratospheric bridge in late winter or the 11-year solar cycle modulates the downward wave signal in the upper stratosphere and mesosphere? Conclusions (2) 17/17

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K. Labitzke 1982, On the Interannual Variability of the Middle Stratosphere during the Northern Winters

Relations between z-component of EP-Flux and zonal wind anomalies in December 1 st EOF for F z 51% 1 st EOF for F z 62% Correlation 0,13

Correlation -0,58 -0,72 -0,31 -0,57 Relations between z-component of EP-Flux and zonal wind anomalies December - January 1 st EOF for F z 51% 1 st EOF for U 30 46%

Contribution of the Second Term

1 st EOF for z-component of the EP-Flux December ( ) 43.3% January ( ) 30.8% February ( ) 38.0% March ( ) 49.0%

PC of 1 st EOF for z-component of the EP-Flux 43.3% for December ( ) 30.8% for January ( ) 38.0% for February ( ) 49.0% for March ( ) 4) Hu, Y., and K.K. Tung, 2003: Possible ozone-induced long-term changes in planetary wave activity in late winter. J. Climate, 16, No Significant Trends! 2005

January February Composites of deviation from 49-year mean Z-component of the EP Flux for Warm Vortex Years Composites of deviation from 49-year mean Z-component of the EP Flux for Warm Vortex Years (x10-5 m2/s2)

January February Composites of deviation from 49-year mean Z-component of the EP Flux for Cold Vortex Years Composites of deviation from 49-year mean Z-component of the EP Flux for Cold Vortex Years (x10-5 m2/s2)

1959,1967,1969,1970,1984,1986, ,1973,1979,1980,1984,1989,1999,2001 December January Composites of deviation from 49-year mean Z-component of the EP Flux Composites of deviation from 49-year mean Z-component of the EP Flux (x10 -5 m2/s2) 3) Charlton, A.J. and L.M. Polvani, 2007: A new look at stratospheric sudden warmings. Part I: Climatology and modeling benchmarks. J Climate, 20,

1 st, 2 nd EOF for z-component of the EP-Flux January NovDecJanFebMar 1PC Jan PC Jan % 18.5%

EOF for z-component of the EP-Flux January EOF for z-component of the EP-Flux January % 23.0% Level 30hPa Level 700hPa

Stratospheric Sudden Warmings January 1977 January 1976 (x10 -7 m/s 2 ) 3) Andrews, D.G., J.R. Holton and C.B. Leovy, 1987: Middle Atmosphere Dynamics. Academic Press, 489 pp. Wind deceleration is found to be large in the neighborhood of large negative values of divergence 1

NovDecJanFebMar Nov Dec Jan Feb Mar Relations between z-component of EP-Flux and zonal wind anomalies U 30 FzFz Negative Positive PC of the 1 st EOF Correlation between PC of the 1 st EOF of EP-flux (z-component) and PC of the 1st EOF of zonal wind anomalies at 30hPa

NovDecJanFebMar Nov Dec Jan Feb Mar Correlation between PC of the 1 st EOF of the divergence of EP-flux and PC of the 1st EOF of zonal wind anomalies at 30hPa Relations between divergence of the EP-Flux and zonal wind anomalies U 30