11 November 2013

On the impact of Typhoon Haiyan in the area around Tacloban

Posted by Dave Petley

One of the most dispiriting aspects of the Typhoon Haiyan disaster in the Philippines is that the high quality forecasting of the storm – it was known some days before landfall that this was a monster and that it would landfall in the area around Leyte – did not lead to a higher level of resilience to the impacts.  The effects in Tacloban appear to be genuinely catastrophic I have noted previously though that in such disasters the initial news reports tend to focus on areas that are accessible to journalists (i.e. that have a working airport, as in the case of Tacloban), whilst the real story is often in the rural areas around the city, especially in upland areas.  My advice to journalists has often been to head for those areas in which there is no communication, which is usually a sign that things are bad there.  It is very hard to know what is happening in the Philippines away from Tacloban City at present.  In the map below I have drawn on the track of the eye of the storm (data from GDACS), and I have also marked the location of Tacloban:

Typhoon Haiyan..

It is also helpful to compare the above with the TRMM image collected by NASA just at the point of landfall.  I have trimmed the original image down to cover the area shown above:

Typhoon Haiyan

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What is clear from the above image is that Haiyan will have affected a vast area across Leyte, Panay and Culion.  An area of particular concern must be the upland areas of Leyte.  This is the track of the eye of the storm across Leyte:

typhoon Haiyan

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On Friday I posted an image of the landslide hazard in this area of Leyte.  Again I have  zoomed in on this hazard map for the area shown in the image above (note red is very high hazard, orange and yellow are medium and low hazard respectively):

Typhoon Haiyan..

What is clear is that the eye of the storm, in which the highest levels of rainfall occur, passed directly over an area of very high landslide hazard.  At present I have seen no indication of the impact of the storm in these areas, and of course they were immune from the storm surge.  However, it would be unsurprising if the picture in these regions is very grave, and of course the likelihood of the people here having received assistance is limited given the situation in Tacloban.