With thousands of people dead, missing or injured, typhoon Haiyan is probably the most powerful tropical storm ever to reach land. New climate data shows that with rising temperatures, more extreme weather of this intensity should be expected.
“The Western Pacific is an area that is prone to very powerful tropical cyclones just because it’s home to the warmest sea surface temperatures and warm ocean temperatures with any given depth,” Ulrike Lohmann, professor of atmospheric physics at the Institute for Climate and Atmospheric Science at Zurich's Federal Institute of Technology (ETHZ), told swissinfo.ch.
“That’s quite important because for all tropical cyclones to form they [have to] take their energy from the evaporation of ocean water." The warmer the water, the more energy is available to evaporate and then be released as part of the cyclone.
The typhoon struck coastal areas on November 8. More than nine million people have been affected, many have lost their homes and are relying on aid for food, water and medicines.
United Nations climate talks in Warsaw, Poland this week have brought the question of human influence on global warming to the fore of people’s minds in light of the devastating typhoon. While there is generally a consensus among climate scientists that extreme weather events are becoming more intense, pinpointing this change on specific factors is more difficult.
“It’s easy to say it [human influence] contributes in some form, that is clear, but in order to analyse what the effect of human influence is, that takes a lot of time,” Lohmann said.
She cited the importance of also looking at variation in natural factors such as wind patterns and the moisture level in the atmosphere, amongst other changing influences.
Highlighting the issue further, the Geneva-based World Meteorological Organization (WMO) on Wednesday released a provisional report on the status of climate in 2013.
The annual climate assessment concluded that concentrations of carbon dioxide and other greenhouse gases in the atmosphere were expected to reach “unprecedented levels” again in 2013, leading to a “warmer future”.
“Although individual tropical cyclones cannot be directly attributed to climate change, higher sea levels are already making coastal populations more vulnerable to storm surges,” said Secretary-General Michel Jarraud.
“It makes sense that the most powerful [storms] become even stronger, just because the ocean is warming and that’s where the main energy for the tropical cyclone comes from,” Lohmann commented.
The Institute for Climate and Atmospheric Science’s climate models predict a further increase in the intensity of the strongest storms.
Switzerland has sent materials for cleaning and distributing drinking water and basic medical supplies to cover 10,000 people for three months. They have also sent a team of 20 humanitarian aid experts to assess victims’ needs, including medical and logistics professionals.
Initial estimates of international aid include a CHF23 million ($25 million) Central Emergency Response Fund from the UN in addition to an appeal for CHF276 million.
Britain has pledged a CHF22 million package including a warship with emergency equipment for drinking water and shelter and the US is giving CHF18.4 million in immediate humanitarian assistance plus varied military assistance.
The ICRC is appealing for CHF87 million to give 100,000 families food, water, shelter and other essentials for 18 months.end of infobox
The WMO says it worked extremely closely with regional and national meteorological centres in the Philippines and Vietnam to give early warnings and prevent the number of dead being dramatically higher.
Around 750,000 people were evacuated from the typhoon’s path based on forecasts and advance predictions, but the widespread destruction could not be stopped.
“Having had this scale of a typhoon…only once in history in 2006 but far weaker, what they [residents of the Philippines] didn’t realise is that aside from the usual damage, this one would bring about severe storm surges,” Jerry Velasquez, head of Advocacy and Outreach for the UN Office for Disaster Risk Reduction (UNISDR), told swissinfo.ch.
“There are reports of storm surges from four to seven metres high. People were saying, ‘If I had known it was like a tsunami I would have done something differently’.”
Originally from the Philippines, Velasquez says the evacuation procedures and warning systems in place are highly regarded, but there are other problems that intensified the typhoon’s impact.
“The area that was hit has a lot of prevalent poverty… most of the housing was actually made of light materials, which are prone to destruction from typhoons of this nature,” he told swissinfo.ch.
He added that in many cases specific evacuation centres were not in existence and buildings such as schools, taken over for this purpose, were not strong enough to withstand the extreme weather conditions, with estimated wind speeds of up to 315 kilometres per hour.
According to the UN Office for Project Services (UNOPS), which aims to combat such problems, the increased frequency and severity of natural disasters “expose communities to a wide range of risks they are often ill-equipped to handle”.
Better prevention is now needed, said Velasquez.
“This is not a once in a lifetime event anymore. That means changing where we plan to put people; if we place people in these coastal areas we have to come up with something else, like cyclone shelters, or we have to improve the building standards, or we address poverty."