Floods will come

THE rainy season has officially strated and a climatologist at the Met Office is warning TT that with the rains the floods will soon follow.

Climatologist Kenneth Kerr gave this warning yesterday at the first session of the community climate outlook forum at Harry Persad and Sons, Mohepath Trace in St Helena. With the passage of a tropical wave through the Caribbean, Kerr announced the official start of the rainy season.

He said the passing of a tropical wave is one of the features used to determine whether or not the rainy season has started. The Met Office said it has been tracking the progress of this tropical wave across the Atlantic Ocean for the past few days. “The moist and unstable environment accompanying the wave produced the much welcomed early season rainfall.” Over 12 hours, from 8 am yesterday, 16.1 millimetres of rainfall was measured.

“Floods have always been part of our climate and they remain part of our climate. Given the geography of TT, given how our landscape is oriented, the flood plains are always vulnerable to run off from the hilly areas, and therefore floods are always going to come. How do we get the information out there. You have to work with us, we cannot do it alone.

“The floods will come. The question is, how will you respond? You have to make decisions. The jury is still out, but research has shown that hurricanes and cyclones are getting stronger. We can’t let this bother us. We have to prepare because we cannot predict the frequency of the storms,” Kerr said.

He said the environment was ravaged by bush fires which will lead to greater run off and the increased chance of flash flooding.

Kerr said from June to December it is likely there will be near average rainfall and the usual number of extreme wet spells. However, below average did not mean dry in the start of the rainy season. “It is still the wettest time of the year, so there could still be a significant amount of rainfall.”

Asked if the rainfall would be enough to replenish water sources which are dangerously low at this time, Kerr said while it will eventually be enough to refill the reservoirs at the end of the season, given the deficit last November, it would take a substantial amount of rainfall. He said even if June is above average, the rainfall could not cover the deficit as it is. “We are looking by say August into October, if we get the kind of rainfall that is typical for those periods, then yes, we can replenish the water sources.

“The bush fires would have primed the environment because now the rains are going to fall and there is nothing to slow it down from reaching the hillsides, and therefore the run off is going to be rapid and with that will come flooding in areas so prone. Those are going to bring flash flooding.”

He said riverine flooding required a number or precursors of conditions so substantial rainfall was needed for the ground to become saturated and the run off quicker. That could happen later unless there was a very aggressive and active start to the early wet season.