Supplementary Movies:
Quasiresonant amplification of planetary waves and recent Northern
Hemisphere weather extremes
Petoukhov, V., Rahmstorf, S., Petri, S., Schellnhuber, H. J. (2013):Quasiresonant amplification of planetary waves and recent Northern Hemisphere weather extremes.
Proceedings of the National Academy of Sciences, published ahead of print March 1, 2013.
[doi:10.1073/pnas.1222000110]
http://www.pnas.org/cgi/doi/10.1073/pnas.1222000110
Data Lineage
Meridional Wind Data
Data was downloaded fromIRI  The International Research Institute for Climate and Society
IRI/LDEA Climate Data Library
DAILY from NOAA NCEPNCAR CDAS1: Climate Data Assimilation System I; NCEPNCAR Reanalysis Project; outline
Intrinsic / PressureLevel / v : meridional wind data
Reference for the data set:
see below
Selection:
Data for the movies was downloaded on Nov 29 2011 13:4437.5N to 57.5 N 180 W to 180 E 300 mb to 300 mb MaySep 19802011
Processing
Processing with CDO to create different aggregations over time intervals.For the runningmean aggregations, the date information shown is the date of the middle contributing time step in the original data.
Calculation of fft(), ifft(), dct(), Spectrum Amplitudes and Phases with Matlab.
Calculation of meridional averages and visualisation with ferret.
Zonal Wind Data
Data was downloaded fromIRI  The International Research Institute for Climate and Society
IRI/LDEA Climate Data Library
DAILY from NOAA NCEPNCAR CDAS1: Climate Data Assimilation System I; NCEPNCAR Reanalysis Project; outline
Intrinsic / PressureLevel / u : zonal wind data
Reference for the data set:
see below
Selection
Data was downloaded on Aug 07 2012 09:5137.5N to 57.5 N 180 W to 180 E 300 mb to 300 mb JulAug 19802011
Processing
As above.Temperature Data
Data was downloaded fromIRI  The International Research Institute for Climate and Society
IRI/LDEA Climate Data Library
DAILY from NOAA NCEPNCAR CDAS1: Climate Data Assimilation System I; NCEPNCARReanalysis Project; outline
Intrinsic / PressureLevel / temp : Temperature data
Reference for the data set:
see below
Selection
Data was downloaded on Aug 09 2012 11:5837.5N to 57.5 N 180 W to 180 E 300 mb to 300 mb JunAug 19802011
Processing
As above.Topography Data
Data was downloaded fromIRI  The International Research Institute for Climate and Society
IRI/LDEA Climate Data Library
NOAA NGDC GLOBE: Gridded 1km, quality controlled global Digital Elevation Model (DEM) data from the Global Land Onekm Base Elevation (GLOBE) Project.
Reference for the data set:
see below
Selection
Data was downloaded on Aug 06 2012 10:31(179.9958W) to (179.9958E) by 0.008333334 N= 43200 pts :grid (35.00417N) to (59.99583N) by 0.008333334 N= 3000 pts :grid
Supplementary Movies
Movie 1
Meridional windfield on 300 mb, between 37.5N and 57.5N, 180W to 180E.For every July of the years 19802011, the daily means are aggregated into monthly means.
This movie shows a synopsis of the meridional windfield, its meridional average, and of the discrete spectrum amplitude and phase of the meridional average.
Each picture corresponds to July of one year, thus it is not a continous time series, but should best be viewed image after image.
For compactness, the presentation as movie format was choosen instead of a collection of 32 single images.
(32s)  as AVI (4.1 MB)  as OGG (1.2 MB)  as WEBM (292 KB) 
Movie 2
Same as Movie 1, but for Augusts.(32s)  as AVI (4.1 MB)  as OGG (1.2 MB)  as WEBM (297 KB) 
Movie 3
Amplitude of waves number 5, 6, 7, 8 of the meridional average of meridional wind at 300 mb, between 37.5N and 57.5N, 180W to 180E.The daily means are aggregated into 15day running means during JuneAugust of 19802011.
The date shown is the date of the middle contributing time step in the original data.
(31.04s)  as AVI (2.9 MB)  as OGG (1.9 MB)  as WEBM (413 KB) 
Movie 4
15day running means of Derivative over time of phases of waves number 5, 6, 7, 8 of the meridional average of meridional wind at 300 mb, between 37.5N and 57.5N, 180W to 180E.The daily values are aggregated into 15day running means during JuneAugust of 19802011.
The date shown is the date of the middle contributing time step in the original data.
The derivative was computed as difference between preceding and following time step, divided by time difference.
Because of the periodicity of the wave, a large phase change in one direction is equivalent to a small change in the opposite direction. Thus, the changes were ``wrapped'' to the interval PI .. +PI.
(31.04s)  as AVI (4.2M)  as OGG (3.4M)  as WEBM (767K) 
Movie 5
Daily values of Derivative over time of phases of waves number 5, 6, 7, 8 of the meridional average of meridional wind at 300 mb, between 37.5N and 57.5N, 180W to 180E.See description of Movie 4 about the calculation of the derivatives.
(31.04s)  as AVI (4.8M)  as OGG (4.1M)  as WEBM (947K) 
Figures in the Paper
For convenience, also the figures are shown below. They were also created based on data from The NCEP/NCAR 40Year Reanalysis Project.Figure 1
Meridional windfield on 300 mb, between 37.5N and 57.5N, 35W to 45E, averages of daily means over three different timespans.
meridional wind (m/s)
and as PDF (13.7x15.1cm)
and as EPS
Figure 2
Meridional windfield on 300 mb, between 37.5N and 57.5N, 180W to 180E, averages of daily means over four different timespans.
meridional wind (m/s)
and as PDF (19x13.8cm)
and as EPS
Figure 3
Time series 19802011 of amplitudes of fourier components of monthly means of meridionally averaged meridionally wind at 300 mb, between 37.5N and 57.5N, 35W to 45E, for wave number (A) 7, (B) 6, (C) 8. July values in green, August values in blue.Inclined dashed straight lines show linear regressions;
horizontal dashed lines show 1.5 standard deviation from the 19802011 monthly climatology (90% confidence level). (Unfortunately, in the PNG format shown here, the dashed lines appear solid. The appearance is correct in the EPS and PDF formats.)
and as PDF (15x15cm)
and as EPS
A variation of Figure 3
Separate figures for July and August data, each showing linear regression, standard deviation, as well as envelope curves that mark the 90% confidence level for linear regression.
and as PDF (15x15cm)
and as EPS
and as PDF (15x15cm)
and as EPS
Figure 4
Latitudinal distributions of K_{s}^{2}a^{2} for two time periods of extreme weather, and `normal' August 1993. See paper text for further explanations.
and as PDF (7.97x7.97cm)
and as EPS
(Unfortunately, in the PNG format shown above, the dashed lines appear
solid. However, note the thin vs. filled arrow heads.
The appearance is correct in the EPS and PDF formats.)
Figure 5
Latitudinal distribution for zonally averaged monthly averaged (A, top) zonal wind at 300 hPa and (B, bottom) temperature at 850 hPa, for 19802011 August climatology, for extreme August 2003, and for 'normal' August 1993.
and as PDF (19.1x17.5cm)
and as EPS
Supplementary Figure S1
Midlatitude meridional wind velocity on different height levels, averaged over two different time periods.
and as PDF (19.3x9.1cm)
and as EPS
Supplementary Figure S2
Similar to Supplementary Figure S1, but for different time periods.
and as PDF (19.3x9.1cm)
and as EPS
Supplementary Figure S3
The meridional windfield as above, but averaged over 31 days in summer 2012.
and as PDF (19x13.8cm)
and as EPS
Supplementary Figure S4
Normalized Effective Forcing between 37.5N and 47.5N
Effective forcing due to temperature and orography, normalized to its
climatology, and weighted with cosine of latitude,
averaged over the latitudinal range 37.5N  47.5N.
The figure shows the amplitudes for waves 6,7,8 plotted over time, monthly
values for July (A) and for August (B).
Wind and temperature data from NOAA NCEPNCAR CDAS1
Reanalysis. Topography data from GLOBE.
and as PDF (17.8x17.5cm)
and as EPS
References

Reference for the wind and temperature data sets:
Kalnay, E., M. Kanamitsu, R. Kistler, W. Collins, D. Deaven, L. Gandin, M. Iredell, S. Saha, G. White, J. Woollen, Y. Zhu, A. Leetmaa, B. Reynolds, M. Chelliah, W. Ebisuzaki, W. Higgins, J. Janowiak, K. C. Mo, C. Ropelewski, J. Wang, R. Jenne, and D. Joseph. The NCEP/NCAR 40Year Reanalysis Project. Bulletin of the American Meteorological Society 77(3), pp 437471, March, 1996. http://dx.doi.org/10.1175/15200477(1996)077%3C0437:TNYRP%3E2.0.CO;2 
Reference for the GLOBE topography data set:
Hastings, David A., and Paula K. Dunbar, 1999. Global Land Onekilometer Base Elevation (GLOBE) Digital Elevation Model, Documentation, Volume 1.0. Key to Geophysical Records Documentation (KGRD) 34. National Oceanic and Atmospheric Administration, National Geophysical Data Center, 325 Broadway, Boulder, Colorado 80303, U.S.A.  Documentation of FFT function extracted from Matlab Version 7.11.0.584 (R2010b) 64bit (glnxa64)
 Documentation of IFFT function extracted from Matlab Version 7.11.0.584 (R2010b) 64bit (glnxa64)
 Documentation of DCT function extracted from Matlab Version 7.11.0.584 (R2010b) 64bit (glnxa64)
 Documentation of ttest2 (Twosample ttest) function extracted from Matlab Version 7.11.0.584 (R2010b) 64bit (glnxa64)
The authors wish to acknowledge use of the Ferret program for analysis and graphics in this paper. Ferret is a product of NOAA's Pacific Marine Environmental Laboratory. (Information is available at http://ferret.pmel.noaa.gov/Ferret/)
Web page created by S. Petri
Update history:
 Wed Feb 27 13:43:23 CET 2013 : added paper reference, made title consistent with heading
 Tue Mar 5 11:04:07 CET 2013 : updated reference and hyperlink after the paper was published on PNAS web site
 Wed Jun 22 11:54:40 CEST 2016: cleaned up hyperlinks
 Sat Feb 6 17:31:14 CET 2021 : improved page header