Regional Council notes

Floods and droughts are nothing new to the Wairarapa and nor are articles on climate change and its predictions.  What has changed though is the reliability of our weather forecasts and our use of them in organising our lives.

In the old days weather forecasts were really a best guess, people prayed for favourable weather and they dealt with what they were delivered.  We had predictions based on when the Pohutakawas and cabbage trees flowered, if the chooks went off the lay or old granny’s arthritis starting playing up.  Senior men in the family tapped the barometer and made solemn announcements about taking your raincoat to school.  

Today, we still have to deal with what is delivered by nature but our forecasting is so much more accurate.  This has been made possible with the use of extremely powerful computers for modelling and satellites supplying real-time information as weather systems track across the globe.

We are now able to access any number of long term weather forecasts which enables us to plan events, be safe in our recreation and off course carry out businesses like horticulture and farming that are reliant on the weather, with greater accuracy.

This all sounds great until you realise that predictions are exactly that and if you try and predict too far out then nature has a way of turning those predictions upside down.  Take November for instance.  

Farmers tell me that they can’t remember a November as wet as this one.  Earlier in the year though, NIWA was predicting the return of a mild El Nino which would typically make Wairarapa drier and windier.  An El Nino pattern would have seen the warm ocean currents around us that brought last season’s hot summer, displaced with cooler waters. 

It’s a perfectly reasonable assumption and one that farmers would have used to plan their season.  The trouble is that the waters are still warm, causing easterly flows which are typically wet and slow moving.  What was predicted hasn’t gone to plan.

So what you might say.  Well the point is that we are lucky in that our short term weather forecast can give us a pretty good indication of what to expect today or tomorrow but the longer term predictions have a greater margin of error.  Please then don’t blame the Dan the Weatherman for our very unusual November.

Adrienne Staples