Hurricane Frances 2004 Float and Mapped data

Eric D'Asaro
Applied Physics Laboratory, University of Washington
dasaro@apl.washington.edu
Dec 22, 2008

The Frances data includes several types of files described below.
All files are flat ascii, with headers describing the data.  Arrays are
listed as vectors with the size given in the header.  For example
array X(i,j) with size i=10, j=20 will be listed as 200 numbers in the order
[i,j]= [ 1 1], [2,1] .... [10,1], [1,2]....


Float21.dat Float22.dat
-----------------------
These are the pressure, temperature and salinity files from two Lagrangian floats 
deployed in Hurricane Frances.  The deployments are described in 
Eric D'saro, Craig McNeil, 2007, Air-Sea gas exchange at extreme wind speeds, 
J. Marine Sys., 66 (2007) 92109.

The floats execute a complicated mission including profiling and Lagrangian drifting 
in the mixed layer.


Mapped_SST.dat
--------------
Mapped_Del_P24.dat
Mapped_Del_26C_Heat.dat	

These files are the mapped data used to make the first 3 panels of Fig. 1 of
D'saro, E. A., T. B. Sanford, P. P. Niiler, and E. J. Terrill (2007), 
Cold wake of Hurricane Frances,Geophys. Res. Lett., 34, L15609, doi:10.1029/2007GL030160

The plots are done in a coordinate system aligned with the storm motion.
This calculation is done as follows: 

The storm track is defined by vectors taken from H*winds maps.
[lonS  latS  ydS]
where ydS is the yearday (0.5 at 12Z on Jan 1, 2008)

  yds        lonS      latS
  244.0625  -61.0460   19.6480
  244.3125  -62.4200   19.8080
  244.5625  -63.8470   20.0190
  244.8125  -65.4500   20.4340
  244.9375  -66.0480   20.5800
  245.0625  -66.7000   20.7750
  245.3125  -68.1810   21.1040
  245.5625  -69.7490   21.4900
  245.8125  -70.6320   21.8990
  245.9375  -71.2980   22.1190
  246.0625  -71.6840   22.3910
  246.3125  -72.8050   22.7640
  246.5625  -73.7810   23.2930
  246.8125  -74.4440   23.9430
  246.9375  -74.9540   24.2130

Although the track is mostly linear, there is a slight curve at later times.
A north-south offset is applied which straightens out the plot 

  ydoff  = [244   246.5  246.8       247.0    ]
  latoff = [  0.    0.  -45/111.2   -63./111.2]
  latS   = latS+interp1(ydoff,latoff,ydS, 'linear' )

The downtrack (X) and crosstrack (Y) positions
are computed from the actual positions of the observations
(lon, lat, yd) where yd is the yearday of the observations
and defined relative to the storm center:

  X = (lon-lonS)*111200*cos(21*pi/180)
  Y = (lat-latS)*111200

and rotated so downtrack is horizontal

  TH = -24*pi/180
  j  = log(-1)/pi
  Z  = (X+j*Y)*exp(-j*TH)
  X  = real(Z);Y=imag(Z)

The final mapped coordinates are thus  [X Y yd].


X-135.000000.dat    X-135.000000.jpg
X70.000000.dat        X70.000000.jpg
X270.000000.dat      X270.000000.jpg
X510.000000.dat      X510.000000.jpg
------------------------------------
These are the mapped data used to make the panels of Figure 3 of the above paper 
and the associated jpg image for the same data.  The filename indicates
the position relative to the storm in the storm translation direction.

------------------------------------

Retrieve files: with "wget", for example

            wget -r -nd http://tao-tc.ucsd.edu/DATA/FRANCES/FLOAT