Expert warns of flash flooding
Zimbabwe must have contingency plans for flash floods that could possibly hit known-vulnerable areas after climate experts predicted above normal rainfall over large parts of the country.
Climate experts said Zimbabweans must be conditioned to prepare for flash floods, violent storms, tropical cyclones and floods in low-lying areas as climate change brings ever more frequent bouts of extreme weather.
Prof Desmond Manatsa, a climate science expert at Bindura University of Science Education, said that Zimbabweans needed to reconsider the risks given that wetter conditions are expected this season.
“I do concur with the national forecast to some extent,” he said.
“The Pacific Ocean had a La Nina and the Indian Ocean Dipole is negative. Both conducive for a normal to above normal rainfall amounts. The methodology which we use for our national forecast is only able to predict total amounts, but has no capacity to incorporate variations within a season.”
Given those risks, Prof Manatsa said rainfall extremes have become more frequent within the season where floods and drought spells occur back-to-back irrespective of the outcome of the season.
“Since observations show that the intensity and frequency of high intra-seasonal rainfall events outweigh that of drought spells in an above normal rainfall and the reverse occurs in a drought year, we can safely say that this season could be characterised by high rainfall episodes within the season especially in the second half,” he said.
“The other aspect that can be derived from the forecast is that it may have an extended end of season. In light of this, I am sure agricultural extension officers should be in a position to offer the appropriate advice to local farmers depending on location. In urban areas, drainage systems should be attended to so that accumulation of rainwater which may cause flash floods is avoided.”