Thursday 14 November 2013

Super Tycoon Monster: Will the COPs strike back?

Super Typhoon Haiyun made landfall in the Philippines on November 7, four days before the official opening of the 19th United Nations Framework Convention on Climate Change, better known as COP19, in Warsaw.

Many agree that Haiyun is the strongest recorded cyclone to make landfall, with maximum wind speeds of up to 195mph, exceeding the top limit of Category 5 on the Saffir-Simpson scale. More than 4,000 have been confirmed dead, and nine million lives have been affected.

 Locals await relief supplies 
Source: AP

A typhoon’s destruction depends on its actual size, degree of low barometric pressure and high sustained winds, and the strength of the storm surge.

This catastrophe serves as a wake-up call, its intensity directly linked to climate change:

Warmer Seas = Bigger Storms: tropical storms feed on heat energy acquired from the sea surface. If the sea-surface temperature (SST) is below 28°C, a typhoon is unlikely to occur.

The SST anomaly is getting bigger due to global warming. A study by MIT professor Kerry Emanuel links SST with hurricane Power Dissipation Index (PDI), which shows overall energy in hurricane/typhoon activity.

Results show a positive correlation in SST and PDI: Northern Pacific cyclone power dissipation has increased by 75% in the past thirty years.


As oceans become warmer, these storms’ heat supply is not limited to the surface: shallow-deep water is also warming. SST anomalies off the eastern coast of Philippines was not unusually high – 0.5 to 1°C above the standard. However, Typhoon Haiyun gathered its energy source from shallow-deep water: 

Despite the increase in storm intensity, their frequency has not increased. This might be because once a hurricane forms at one spot, it leaves behind cold, stripped-of-heat surface water, which makes it harder for the next hurricane to form.

The damage of Haiyun was also caused by the twenty-meter storm surge. As seas become warmer, they expand, causing a sea-level rise and a relatively higher storm surge.

The disaster casts a direct spotlight on world leaders in Warsaw to enforce aggressive goals to combat climate change. Philippine Climate Change Commissioner Naderev Sano pledges that he will not eat at the convention until ‘a meaningful outcome is in sight’.


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