296

List  of  Figures

List  of  Figures

Atmospheric  Physics
Figure  2-1:  Sea  level  pressure  (hPa)  for  the  gale  “Kerstin“  of  March,  31  2010  together
with  grid  positions  of  weather-typing  scheme  and  classification  (Cyclonic/Gale).  ...  42
Figure  2-2:  Percent  frequencies  of  reduced  weather  types  for  2008  (blue)  and  2009  (red)
along  with  empirical  distributions  for  1971-2000  (stacked  columns).  Percentile  range
Min  to  Max,  internal  interval  limits  at  10,  25,  50  (median,  continuous  stepline),  75  and
90%  52
Figure  2-3:  As  Figure  2-2,  except  for  monthly  absolute  frequencies  (days)  53
Figure  2-4:  As  Figure  2-2,  except  for  2010  and  2011.  ^4
Figure  2-5:  As  Figure  2-2,  except  for  monthly  absolute  frequencies  (days)  in  2010  and
2011  55
Figure  2-6:  Weather-type  transitions,  annual  climatology.  The  arc  length  of  a  ring  section
reflects  the  frequency  f  in  days  of  weather  type  X  (marginal  sum  of  countmatrix  ф  in
Table  2-19).  The  segments  within  section  X  depict  stacked  frequencies  of  transitions
Y*X-X  (column  entries);  they  are  colored  after  the  preceding  weather  type  and

given  in  ascending  order;  the  leftover  portion  of  section  X  is  associated  with  self
transitions  Y—X  —  X.  Transitions  X—  Y*X  (row  entries),  colored  after  the  succeeding
weather  type,  are  identified  by  the  sockets  of  Bézier  ribbons.  The  ribbons  have  color
X,  if  f(X  —  Y)  >  f(Y  X),  otherwise  color  Y.  The  figure  was  created  with  the  software

package  Circos  (KRZYWINSKI  et  al.  2009)  57
Figure  2-7:  Same  as  Figure  2-6,  except  for  2008  and  2009  59
Figure  2-8:  As  Figure  2-6,  except  for  2010  and  2011  60
Figure  2-9:  Seasonal  sea  level  pressure  distributions  (SLP,  hPa).  Left:  NCEP/NCAR  climatology ­
  (1971-2000).  Middle:  2008,  SLP  &  SLP  anomalies  (colored,  contour  spacing ­
  1  hPa).  Right:  2009,  ...  Red:  Distribution  type  (SLP  or  SLP/SLPA)  and  season
(JFM,  AMJ,  ...  -  winter,  spring  ...)  61
Figure  2-10:  As  Figure  2-9,  except  for  2010  and  2011  62
Figure  2-11:  Monthly  sea  level  pressure  distributions  (SLP,  hPa)  in  2008  together  with
departures  from  the  NCEP/NCAR  climatology  for  1971-2000  (SLPA,  colored,  contourspacing ­
  1  hPa).  Red:  Distribution  type  (SLP/SLPA)  and  month  (J,  F,...  -  January,
February...)  63
Figure  2-12:  As  Figure  2-11,  except  for  2009  64
Figure  2-13:  As  Figure  2-11,  except  for  2010  65
Figure  2-14:  As  Figure  2-11,  except  for  2011  66
Figure  2-15:  Seasonal  50%  probability  ellipses  for  the  „North  Sea  Wind“  (1  -  winter ­
  -  JFM,  2  -  spring,  etc.);  top:  2008,  bottom:  2009  67
Figure  2-16:  As  Figure  2-15,  except  for  2010  and  2011  68
Figure  2-17:  Progressive  daily  vectors  of  the  “North  Sea  Wind’’  with  ensemble  and  climatology.

  Markers  indicate  the  first  day  in  a  month,  years  final  points  of  ensemble
members.  All  trajectories  start  at  1  -(0,0),  and  proceed  by  adding  consecutive,  daily
wind  vectors.  Dividing  the  along-path  length  of  a  trajectory  and  the  linear  distance
between  any  two  markers  by  the  associated  time  interval  in  days  yields  the  scalar

wind  velocity  and  the  vectorial  wind  speed  in  m/s  for  that  period  71
Figure  2-18:  As  Figure  2-17,  except  for  2010  and  2011  72