Wind hazard over South Eastern South America considering current as well as future climate conditions

SANABRIA A.; CARRIL A. F.; CECHET R.P.

Sidney

Conferencia; Joint 25th AMOS-ICSHMO; 2018

AMS

Wind is one of the most dangerous natural phenomena for the built environment in South EasternSouth America. The hazard posed by wind depends on the extreme wind speeds on the surface andcan be quantified by calculating the Average Recurrence Interval -more commonly known as ReturnPeriod- of these winds.Curves of Return Period of extreme wind speeds are used by planning authorities to enforceappropriate standards for infrastructure construction in most countries of the world. These maps areusually built up from wind speeds recorded at a network of weather stations. In some countries,however, the quality of the records is poor because of short length, poor recording practices, scarcestations distributed over long distances, instrument calibration and maintenance. To overcome theselimitations we discuss an alternative procedure to calculate wind hazard based on wind speedscalculated by climate models.A recent, collaborative effort for producing ensembles of regional climate model simulations havebeen developed in the framework of both CLARIS EU-FP6 and CLARIS-LPB EU-FP7 projects. Thesestudies contributed the first high-resolution coordinated multi-model regional climate simulations toanalyse climate change scenarios over South America. By extracting wind speeds from thesesimulations and calculating the corresponding curve of Return Period in each cell of the simulationgrid we have produced maps of wind hazard over South Eastern South America.Another advantage of this method is that it facilitates the assessment of the impact of climate changeon wind hazard, a matter great of importance for planning and emergency authorities.Map quality was evaluated by comparing results from the climate simulations with results fromreanalysis. The comparison shows that the climate simulations produce results close enough to thereanalysis and hence they can be used for wind hazard assessment. The results also show that we canexpect little variation in wind hazard in South Eastern South America by the end of the century.