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					Contribution P1.05
      To day is
 September 11, 2008.
Just 7 years ago on
September 11, 2001,
around 8h45m ET…
   In Manhattan New York
something terrible happened…




                               3
    In Manhattan, New York
the WTC was hit and destroyed




                                4
Let we remember it…   5
    Atlantic Hurricanes,
Geomagnetic Disturbances and
Cosmic Ray Intensity Changes.


              S. Kavlakov
    Bulgarian Academy of Sciences
        (skavlakov@gmail.com)

                                    6
 As it is well known that the hurricanes are
  high velocity circular winds born over the
     hot equatorial waters of the oceans.
Their whole vortex generally spread out to
       gigantic rings with a diameter of:
        several hundred kilometers.
  The energy accumulated during these
     processes is enormous. It could be
 compared with the energy of explosion of:
  more than thousand Hiroshima type
                atomic bombs.
                                          7
That enormous energy explains the
  vast disasters produced by the
  hurricanes, when they touch a
          populated area.




                                    8
         After Katrina - August 2005:
             Hundreds were killed,
more than a hundred thousand were left homeless.




                                               9
       After Katrina - August 2005:
…and that remained from the South suburb of
               New Orleans.




                                              10
    That also added to our interest for a
     detailed study of a possible similar
    parallel between the appearance and
    development of the hurricanes from
       one side and the geomagnetic
       disturbances and Cosmic Ray
           intensity from the other.

       Finding even slight statistically significant
interconnection between them could surely help a better
hurricane early predictions and safe a lot of human lives.

                                                       11
      Lately, the question if several purely
  meteorological processes of the terrestrial
     atmosphere are connected with the
        magnetosphere disturbances,
            CR intensity changes,
and solar activity has been largely discussed:
          (Kudela and Storini, 2005),
              (Marsh et al. 2000),
               (Svensmark 1998)
               and many others.

                                                 12
          In some of our earlier works
a significant statistical relationship has been
                 found between
geomagnetic activity as measured by the KP
                       index
 and hurricane intensity as measured by the
              maximum wind speed.
     Persistent appearances of sharp CR
     intensity changes before the starts of
        some hurricanes have been also
                    observed.


                                                  13
     For our work, presented here,
      we used the following data:
• All 6 hours hurricane data recorded in the 55
  years interval 1951-2005. [80665 data]
• All 3 hours Geomagnetic Kp indexes recorded in
  the same 55 years long interval [160704 data].
• All 1 hour CR data measured continuously 55
  years with the Neutron Monitor of [482136 data].
          Climax high mountain station:
           39.37N; 106.18W; alt. 3400 m.
              2.97 GeV cut-off rigidity.
                                                 14
             Now:
• Instead of hurricane rotational
   wind velocity W used earlier,
             now we use
     its first derivative dW/dt,
    assuming that it is directly
   connected with the hurricane
      energy intensification.
                                15
We found a persistent presence of at least one
Forbush Decrease event (FE), in the time
interval of about 3 to 16 days before the start
of considerable number of hurricanes.

A sharp rise in the geomagnetic parameters
KP was also noticed in the time intervals
preceding the star of many hurricanes.

   All that is centered around the hurricane
            starts (yellow triangles).


                                             16
       Some noticeable Interconnections.
 3                                                                 ABBY-start [0]:1960.Jul.10.
 2      CR %                                          500
                                                              Kp, W,
 1                                                    400     dW/dt
 0
-1                                                    300
-2                                                    200
-3
-4        ABBY                                        100
-5     1960.Jul.10.
                                             days       0
-6
                                                            -34 -29 -24 -19 -14 -9     -4   1   6     11 16 21
     -34 -29 -24 -19 -14 -9   -4   1   6   11 16 21                                                       days

2                                                                      CELIA-start [0]: 1970.Jul.31
         CR %                                         500
1
                                                             KP, W,
0                                                     400
                                                             dW/dt
-1                                                    300
-2
                                                      200
-3
         CELIA                                        100
-4     1970.Jul.31.
                                              days     0
-5
                                                            -34 -29 -24 -19 -14 -9     -4   1   6     11 16    21
     -34 -29 -24 -19 -14 -9   -4   1   6   11 16 21                                                      days
                                                                                                          17
          And also for two of the most powerful hurricanes.

 3                                                                     MITCH-start [0]: 1998. Oct. 22
                                                         500
         CR %                                                                  KP, W,
 1                                                       400                   dW/dt
-1                                                       300

-3                                                       200

-5                   MITCH                               100
                  1998.Oct.10.                    days
                                                          0
-7
                                                               -34 -29 -24 -19 -14 -9    -4   1   6   11 16      21
     -35 -30 -25 -20 -15 -10 -5    0   5   10 15 20                                                        days

3                                                                   KATRINA-start [0]: 2005. Aug.23
          CR %                                           500
1                                                                                       KP, W,
                                                         400
-1                                                                                      dW/dt
                                                         300
-3
                                                         200
-5
         KATRINA                                         100
-7      2005.Aug.23.                       days
                                                          0
-9
                                                               -34 -29 -24 -19 -14 -9    -4   1   6   11   16 21
     -34 -29 -24 -19 -14 -9   -4   1   6   11 16 21                                                        days

                                                                                                            18
             On the previous slides,
   four powerful hurricanes are presented to
                    illustrate that.
                        There:
the hurricane rotational velocity (W-red line)
and its derivative (dW/dt-blue line)
are overlapped on the daily changes of the
Kp geomagnetic index (black bars).
             Arbitrary units are used.

                                                 19
                          But, sorry,
 it is difficult to find even an relatively stable average
  time difference between the starts of these events.

             Earlier we accepted as basic points the
                   start days of the hurricanes
            and made our calculations towards them.

                 Here we chose another basic days:
1. We defined as Kp”0” these days when the Kp index is 70% above
                     the total 55 years average.
  2. We took as Forbush Event FE”0” these days when the sudden
 decrease of the CR intensity is below -3% from the local average.

     For these “0” days we take the corresponding hurricane
                  intensification values [dW/dt].


                                                               20
Trying to find a interconnection between the hurricane intensification (dW/dt) and
the appearance of High KP or FE, we divided all our hurricane hours in two parts:


 1. Over a vast area of hot waters (shown as white rectangle on the map),
where the intensification comes mainly from the vertical streams powered by
                        the high surface temperature.

   2. And over the whole remained, area, with relatively low water surface
 temperature and near to land. There we could expect a moderate influence
of the powerful atmospheric factors and probably more noticeable influence
                        of the geomagnetic factors.




                                                                               21
Results:




           22
• As it could be expected: the intensification over the hot
     ocean waters is about 10 times more powerful than
                over the other oceanic areas.
            [0.313 kt/hour toward 0.0342kt/hour]
 • Over hot waters the intensification increases around
          the corresponding “0” days are smaller.
  [73% toward 108% for Kp, and 16% toward 60% for FE ].

• We assume that there is a possibility to accept a small
  participation of some unknown mechanism, connected
     with the geomagnetic factors to the intensification
                          process.
   • Naturally, over hot water the main intensification
     process is very powerful, so the influence of this
                   mechanism is reduced.

 The statistical significance was estimated by means of “bootstrap” procedure.
                                                                             23
 Overlapping the hurricane intensifications dW/dt for Kp”0”
                     and for FE”0” days,
  as well as six days before them and six days after, we
                    obtained these graphs.
 Only three days (in bold red on the graphs) around the “0”
         day and the “0” day itself (the yellow triangle)
              were taken for our evaluations.
                Days around KP"0" day                                           Days around FE"0" day
0.7   dW/dt                                                     0.7   dW/dt
0.6   kt/hr                                                     0.6   kt/hr
0.5                                                             0.5

0.4                                                             0.4

0.3                                                             0.3

0.2                                                             0.2

0.1                                                             0.1
                                                days                                                                    days
0.0                                                             0.0
      -6   -5   -4   -3   -2   -1   0   1   2   3   4   5   6         -6   -5   -4   -3   -2   -1   0   1   2   3   4     5    6




                                                                                                                               24
                      Conclusions. 1.
•   Over all the Atlantic the intensification dW/dt rise around KP and FE “0”
    days.
•   The rise is well expressed far from the hot oceanic waters
•   The intensification is larger AFTER the corresponding “0” day.
•   In the case of KP that rise is significant
•   In the case of FE the rise is minor and unstable.
•   But taking in account their persistent appearance before the hurricane
    start [depicted on the first graphs.] probably the FE contribution to the
    storm intensification is within a longer time range


                    Because of all that
                            and
     because the large amount of investigated hurricanes
           in an interval of more than half a century,
     we could permit ourselves to support the existence of
    a slight geomagnetic influence on the hurricane energy.
                                                        25
            Conclusions. 2.
• The result is consistent with an earlier study
  in showing a connection between Kp values
  and hurricane intensity. It expands on the
  earlier work by focusing on intensification
  rather than intensity.
•   Along the lines of our earlier study we
  suggest that a possible physical mechanism
  is related to increased ionization of the upper
  extent of the tropical cyclone vortex leading
  to increased condensation and additional
  warmth throughout the column. Obviously
  more work is needed to better understand
  this interesting result.
                                                26
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posted:3/28/2011
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