Typhoon Haiyan: Sign of what's to come with climate change?


By Bob McDonald

The devastation in the Philippines from the strongest storm to ever hit land is a reminder of things to come, as storms gather strength on a warming planet.

While it is not yet possible to say the unprecedented power of Typhoon Haiyan is due to climate change, climate models have been predicting that tropical storms will carry more energy in the future, so scenes like those in the Philippines could become more common.

The culprit behind the gathering storms is rising ocean temperatures, which are on the increase along with atmospheric temperatures.  

In fact, it is the absorption of heat by the oceans that is responsible for the recent decline in the rate of atmospheric warming. The environment is still heating up, but not as fast as predicted. 

That's not a reason to celebrate. It's like saying this house is not burning as fast as we thought, but it's still burning.

Warm water is like jet fuel for tropical storms. It provides the energy that drives the winds and provides extra moisture for rains. 

On average, global ocean temperatures have risen about half-a-degree Celsius, but there are hot spots, such as the Gulf of Mexico, which provided a boost to Hurricane Katrina as it approached New Orleans. There was also a region of warm water off the coast of the Philippines, where Haiyan was born.

Although records for the South Pacific are less complete, weather data for the more closely monitored North Atlantic have shown that tropical storms and hurricanes in that region are carrying more energy, which fits the climate model predictions.

As storms get stronger, so does the ocean surge that comes with them. Tropical storms act as huge suction cups on the ocean, picking up the surface in a huge dome shape that the storm carries along with it. 

This dome is whipped up higher by the winds within the storm and the storm's forward motion. y the time it reaches shore, a surge can be more than 10 metres above sea level, easily pouring over seawalls and flooding the land behind. f the storm happens to arrive at high tide, the effect is even worse. 

Since islands are at sea level, they are most susceptible to flooding from these surges.

Haiyan is not the strongest storm ever recorded, but its impact was devastating because it tracked directly over the densely populated Philippines. So did Hurricane Sandy when it struck New York and New Jersey. But the big difference in these two cases is that the American storm had fewer casualties because buildings along the Jersey Shore are stronger than those in the Philippines, and the U.S. had the resources to rebuild the damaged areas quickly.

The Philippines are a struggling economy, where people live in poorly constructed buildings that are easily swept away by strong winds and floods. Collapsing buildings kill people as much as strong winds and sweeping floods.

That's why island countries have spoken out loudly at climate conferences, such as the current UN session in Warsaw, urging members to move ahead with efforts to reduce carbon emissions. They are the first to be affected and have the most to lose.

Sadly, carbon dioxide levels continue to rise worldwide, as many countries - including Canada - fail to meet their emissions targets.  Perhaps the images of those who have lost everything in the Philippines will put a human face on what is to come, as tropical storms gain more strength in the future and bring their wrath to those who are least responsible for climate change - but stand to suffer the most from the consequences.