Data use cases

Katrina: Methodology | Results

2.4.2 Observing wind and waves: hurricane Katrina Wind and waves observed in the case of an extreme meteorological event.

Results

Once the different operations are executed, you can plot them in the "Views" tab. Define minimum and maximum X for the plot (between 17 and 30°N); you can also use maximum Y at 15 m for SWH or 30 m/s for wind speed (minimum being 0). You can define two views : one for SWH, one for wind speed. Resulting plots should look like the ones below:

First three plots are SWH, second three are wind speed. T/P and Jason-1 are together on the first (T/P in green, Jason-1 in blue-grey), Envisat on the second (red) and GFO is on the third (blue).

Comments

• Topex and Jason-1 recorded significant wave heights up to 5 metres, and wind speeds around 20 m/s.
• Envisat crossed Katrina very near the eye of the storm and measured wave heights well beyond 10 metres and wind speeds around 30 m/s (wind speeds higher than 20 m/s can not be measured reliably; the algorithm used at that time in Envisat processing is making the plateau in the wind speed line).
• GFO caught up with Katrina shortly before making land fall. Wave heights and wind speeds sustained at 10 metres and near 30 m/s, resp., with higher values measured near the coast.
• Wind speeds and wave height distributions appear asymmetric, with higher values measured windward of the eye.

See Fig. 3 in the Application about Cyclones, hurricanes and typhoons
Scharroo, R., W. H. F. Smith, and J. L. Lillibridge, The impact of dynamic topography on the intensification of hurricanes, 15 years of progress in radar altimetry Symposium, Venice, Italy, 2006