Thursday, September 29, 2011

Understanding local realities in the face of disaster triggers like hurricanes

Hurricane Ophelia passed through the west coast of Dominica on 28 September 2011. This is the third hurricane in the past 12 years whose effects emerge out of the mostly placid Caribbean Sea to blast the West Coast. The first was Lenny in 1999, it severely destroyed roads since it was accompanied by huge sea swells. The second was Omar in 2009; this time fishing boats perished. Yesterday Ophelia brought torrents of rains inundating homes, sweeping away vehicles and destroying roads. The communities of Canefield, Massacre and St. Joseph were hardest hit.

The irony of all three disasters is the surprise disaster coordinators display at the aftermath - a surprise that appears to stem from limited understand of the mechanics of hurricanes, their interaction with element of rain and the Dominican topography. An even deeper misunderstanding is the impact in relation to the location of hurricanes as well as the size of these hurricanes.

On September 28, Ophelia was over 350 miles wide, had tropical force winds extending 175 miles (280km) from the center. Clearly, with Dominica located about 360km south of Ophelia's center and well within depression wind strength, Ophelia was bound to hit.

With Ophelia located due north of Dominica, and since hurricane wind move in an anti-clockwise direction, owing to the effects of the Coriolis Force in the Northern Hemisphere, the effect had to emerge from the Caribbean Sea. That direction was clearly visible from the cloud movement. As the winds passed over the Caribbean Sea they picked up moisture released as water evaporated over the sea surface.

Once these moisture laden winds reached the coastal highlands they were forced to rise (Orographic lifting). When air rises its temperature falls and the amount of moisture it can hold reduces (The amount of moisture air holds depends on its temperature, the higher the temperature, the more it holds), and the excess therefore fell as rain. Yesterday it was torrential rain, given it was emerging out of the nearby warm Caribbean Sea causing disaster.

This happened because of the unplanned nature of housing on the west coast, the hilly topography and the weaknesses in our analysis of data released by the National Hurricane Center, since we merely relay the information. We fail to understand the local dynamics which are not captured in hurricane advisories. Besides our tendency even among leaders to decry attempts at proactive disaster mitigation measures create uncertainty even when the sign of danger are unraveling.

Moreover, we have not appreciated that hurricanes are four-pronged events - wind, rain, floods, sea surges and slope failures.And one or more can emerge when hurricanes hit. Dominica is the the Caribbean country most susceptible to disasters with a 10% change of hurricanes each year of a hurricane (Florida is the highest at 15%). Dominica is brushed or hit directly at least once every 4 years (hurricane city, 2011)

We need to spend money in identifying, recruiting and training in disaster analysis and management up to the Masters level and beyond because of this vulnerability o to disasters triggered by natural events. That training must be broad-based and integrated.

We need to have a sustained program of disaster and emergency education that has its foundation in our curriculum as the present treatment does not go far enough (It is superficial and is not grounded in the Dominican realities). We need to develop a land capability survey and remove people from areas where they are vulnerable because ultimately government has to bear the cost of recovery for many of the victims of these disasters.

We also need to train our current disaster managers and meteorologiists to know it is OK to give expert advice or make strong recommendations for action particularly when events have begun to unfold. we must go further than simply quote weather reports - disaster scenarios must be proposed. The chaos which ensued as people waited long hours in vehicles and under torrential rain and flooding to get out of harms way during Ophelia could have been avoid.

Finally, disasters are not acts of God. They are the actions of men in the face of nature. The simple presence of a hurricane does not lead to disasters. Disasters happen when protections collapse. Giving sound advice is part of that protection and sound advice must be grounded in the Dominican reality. We must do more that relay reports, we must understand their interaction with the Dominican landscape and its people, if we are going to meaningfully contribute to saving life and property.

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