66
K.B. Katsaros
Fig. 4.5 Minimum
atmospheric pressure at sea
level during the passage of
hurricane Katrina in the Gulf
of Mexico in 2005; showing
the observations (black), and
the reduction of error in the
GFDL model with (red) and
without (green) using the
TCHP in the coupled
atmosphere-ocean TC model.
Provided by G. Goni
The concept has been further developed and improved with regular information on the structure in the upper ocean provided by airborne extended bathythermographs, AXBTs, dropped into the sea ahead of storm passage, or more
recently by the data from drifting ARGO buoys. The depth of the 26 ◦ C isotherm, is
used as a piece of input data in calculating THCP. The 26 ◦ C value is chosen because
this is the temperature associated with TC genesis. Operational estimation of TCHP
based on altimeter data is now available via the web. 2 The work has been extended
to the warm eddies off Taiwan and reported by Lin et al. (2009).
4.2.5 SAR Observes TCs
The Synthetic Aperture Radar, SAR, on SEASAT was very experimental and much
practical and theoretical work was required to interpret the data from a moving
sea surface. ERS 1 and 2 also carried a SAR from whose data sea surface wave
spectra could be calculated. The RADARSAT 1 SAR launched by the Canadian
Space Agency, CSA, in 1998, had several modes of operation. One of them was in
“wide swath mode” or SCAN-SAR at about 250 km swath width with 50–100 m
resolution. Such data were only collected occasionally and had to be ordered weeks
in advance.
However, as a few images were collected, which showed very interesting features, the CSA developed a program called “Hurricane Watch” to plan for data
2 See http://www.aoml.noaa.gov/phod/cyclone/data/
K.B. Katsaros
Fig. 4.5 Minimum
atmospheric pressure at sea
level during the passage of
hurricane Katrina in the Gulf
of Mexico in 2005; showing
the observations (black), and
the reduction of error in the
GFDL model with (red) and
without (green) using the
TCHP in the coupled
atmosphere-ocean TC model.
Provided by G. Goni
The concept has been further developed and improved with regular information on the structure in the upper ocean provided by airborne extended bathythermographs, AXBTs, dropped into the sea ahead of storm passage, or more
recently by the data from drifting ARGO buoys. The depth of the 26 ◦ C isotherm, is
used as a piece of input data in calculating THCP. The 26 ◦ C value is chosen because
this is the temperature associated with TC genesis. Operational estimation of TCHP
based on altimeter data is now available via the web. 2 The work has been extended
to the warm eddies off Taiwan and reported by Lin et al. (2009).
4.2.5 SAR Observes TCs
The Synthetic Aperture Radar, SAR, on SEASAT was very experimental and much
practical and theoretical work was required to interpret the data from a moving
sea surface. ERS 1 and 2 also carried a SAR from whose data sea surface wave
spectra could be calculated. The RADARSAT 1 SAR launched by the Canadian
Space Agency, CSA, in 1998, had several modes of operation. One of them was in
“wide swath mode” or SCAN-SAR at about 250 km swath width with 50–100 m
resolution. Such data were only collected occasionally and had to be ordered weeks
in advance.
However, as a few images were collected, which showed very interesting features, the CSA developed a program called “Hurricane Watch” to plan for data
2 See http://www.aoml.noaa.gov/phod/cyclone/data/