An atlas by the National Institute for Water and Atmospheric Research (Niwa) tracks the risk of major saleyards being in the path of aerial plumes of the disease originating from piggeries in high-risk weather conditions.

Aerial spreading of the disease is most likely to happen in Canterbury in autumn and winter, when an inversion layer traps warmer air over a cooler land mass.

Using computer models, a team of five scientists plotted the potential course of the viral plumes. Weather records were analysed to predict conditions favouring the airborne spread of the disease in the three-month national study commissioned by Biosecurity New Zealand.

While airborne dispersal is uncommon, it is difficult to control and can have far-reaching consequences when the right weather conditions coincide.

Niwa mesoscale meteorologist Dr Richard Turner said the climatological-risk atlas would help Biosecurity New Zealand in its preparation to respond to an outbreak of the disease.

Source: Stuff.co.nz