Monster Cyclone Haiyan

Following on from my post about tropical cyclones in the 'Past, Present and Future', I am now going to discuss the recent cyclone Haiyan in the Philippines. One month after Haiyan, the death toll stands at 5,924 and 1,779 people are still missing as per government figures released last Sunday.

'Galvanised iron sheets were flying just like kites' 

(Mai Zamora from World Vision).

Haiyan was one of the strongest typhoons ever to hit land with winds of up to 320 km/h (BBC News). Sustained wind speeds of that extent are what we would expect of a category five hurricane. These winds caused waves as high as 15 metres and up to 400mm of rain in some places. These extreme conditions caused destruction that was extensive and devastating.

Figure 1: Satellite image as Haiyan approached the Philippines

In terms of the damage to infrastructure, the storm caused widespread damage. Reports of building being ripped apart, flash floods and landslides were rampant. The country was in a state of chaos whereby schools and offices were closed, flights were suspended and soldiers were entrusted with rescue and relief operations. Furthermore, the storm meant that power and communication lines were cut to some areas.

Haiyan affected millions of people, 12 million according to officials. Even the capital felt the force of the storm despite being far away from the eye of the storm, however other cities weren't as fortunate. Raging across Leyte and Samar, it turned roads into rivers and left Cebu city devastated, home to over 2.5 million people. The black arrow in figure 2 indicates the path of the storm. It suggests that the storm passed through some of the most densely populated parts of the Philippines therefore affecting an extensive proportion of the population. 

Figure 2: population density of the Philippines

The Philippines has experienced numerous super typhoons over the past decades. Haiyan was the 25th to enter the territory this year. Scattered along the worlds most active typhoon belt, there are plentiful supplies of warm water and moist air to provide the energy to kick start super storms. Despite these factors concerning the formation of a cyclone, Haiyan has shown a number of unusual features. 

As explored in my previous post, the walls of the storm that normally rotate around the eyes are replaced as it moves, often weakening the wind speed. In the case of Haiyan, this didn't happen. Further to this, the upwelling of cold water which would usually serve to reduce the energy of a storm did not take place as Haiyan was travelling so quickly. These two factors meant that Haiyan was unique in nature. 

Figure 3: typhoon Haiyan relief effort

In a blog post by Jeff Masters, the damage is described as 'perhaps the greatest wind damage any city on Earth has endured from a tropical cyclone in the past century'. Figure 3 gives just a snap shot of the damage. 

The question is: will this trend of monster cyclones gain momentum in the future? Does anthropogenic climate change have a role in the increasing frequency and severity of so called 'natural' disasters? Find out more on hurricanes through the Anthropocene next time.