Preparing for wet conditions with El Nino

A Southland council is readying itself for the potential fallout of an El Nino event which could bring wet weather to the South.

Described by Earth Sciences New Zealand as a global phenomenon resulting from warming water in the Pacific, the impending El Nino is expected to bring dry conditions to much of New Zealand.

But Environment Southland general manager science Karen Wilson said the South was in a different situation from most of the country — which was preparing for drought.

A report prepared for a Wednesday meeting showed annual rainfall in Southland was 10% to 14% higher in El Nino compared to La Nina or neutral years — noting issues such as erosion, flooding, impact on agriculture, and sediment and nutrient runoff.

The report said while there was an increased chance of more rainfall and river flow in winter, the biggest jump was expected in summer.

Nationally, peak El Nino conditions were expected in summer and the event could have ‘‘significant impacts’’, it said.

Councillor Phil Morrison suggested the council promote being ‘‘super prepared for a super El Nino’’ to get people thinking about resilience, while councillor Lyndal Ludlow asked how information on El Nino could be applied to some planned council operations.

Ms Wilson said compliance was looking at how a wet spring and summer could be handled and noted the impact of weather conditions on consent holders in previous years.

The council report said Southland’s cumulative rainfall for 2026 was at 81% of the long-term average and the region’s aquifers would benefit from more.

Earth Sciences New Zealand describes El Nino and La Nina as opposite phases of a global climate cycle which appear every few years.

• LDR is local body journalism co-funded by RNZ and NZ On Air.