The super El Niño that cost New Zealand more than $1 billion

Friday, 17 July 2026

Waikari farmer Peter Roberts had to slash his friesian bull yearling herd from 170 to 50 in hopes of surviving the 1990 drought.

ANALYSIS: It’s strange how environmental agencies and governments always officially “declare” an El Niño.

It makes it seem like a declaration of war. And maybe it is in some countries – but maybe it doesn’t need to go quite that far in New Zealand anyway.

Declaring something is highly emotive. It ups the ante.

Tankers were delivered water to Hawarden and Waikari schools after a plea to the council for drinking water as both townships experienced a total ban on hosing and a diminishing water supply in September 1998.

We should certainly be preparing as much as possible for a challenging spring and summer, as predictions continue of a very strong El Niño, potentially one of the most intense in the past 100 years.

Yet as University of Waikato climate scientist Dr Luke Harrington says, perhaps we need to be less excited about the declaration, take a deep breath or two about the approaching event and think rationally about it.

“Relative to other parts of the world, we’ve actually got quite a weak relationship between ENSO (El Niño-Southern Oscillation) and the weather we experience.”

Burnt-yellow hills and paddocks became a familiar sight as one of New Zealand’s most damaging El Niño droughts took hold in 1997-98.

What Harrington means is we should keep its likely impact on New Zealand in perspective, considering what El Niño can bring to other parts of the world, where the lives of many millions can be threatened by famine, fire and flood.

In the last column we looked at the major El Niño of 1982-83, which brought a cold and memorably stormy summer to eastern and southern parts of the South Island especially.

The next super El Niño, in 1997-98, was remarkably different, proving there is no such thing as “normal” El Niño conditions in New Zealand.

An aerial view of dry Canterbury farmland in 199 shows the contrast with areas under irrigation.

While the 82-83 event dropped to -33.3 on the Bureau of Meteorology’s Southern Oscillation Index (SOI), this one was slightly less strong, bottoming out at -28.5 in March 1998.

Despite that, its effects were more widespread and damaging to the economy, with some economists estimating the drought it brought cost the country more than $1 billion in lost production and earnings.

After a very dry end to winter and a bone-dry spring in 1997, the summer drought was especially bad from Hawke’s Bay down through the Wairarapa, and extreme in places throughout Marlborough, Canterbury and North Otago. In some locations, there was less than half the average summer rainfall, with just 30-40mm recorded from December to February. The hills and plains turned burnt yellow then tan.

Hurunui mayor John Chaffey is teased by heavy clouds that failed to deliver to the parched ground in Amberley in September 1998.

Much of the rest of the North Island was also unusually dry, except for Taranaki and parts of the King Country. Those in Auckland and the far north reliant on tank water suffered long waits, while very warm days put heavy demand on electricity for air conditioning.

While significant rain started returning to the north of the country during February 1998, it stayed away for parched eastern regions of both islands until March or even April.

New Zealand has experienced debilitating droughts before. During the 1972-73 summer El Niño, the entire country was significant drier than normal, including the West Coast and Southland, which are often wetter than usual in an El Niño.

But what made 1997-98’s desiccation even worse was the persistent heat, which peaked in February. That month became New Zealand’s hottest on record, until it was surpassed in January 2018.

Instead of the cold southwesterlies which prevailed in 1982-83, warm nor’west airflows predominated this time.

Temperatures were especially high in Christchurch and across Canterbury. Between November 24, 1997, and March 24, 1998, there were 23 days in the city of 30C or higher, five with highs above 34C. On January 3, it got to 35.5°C and on March 24, incredibly, it was 35.2C. On another 10 days, maximum temperatures reached between 28C and 30C.

In an average Christchurch summer, you might expect several days to reach 30C or more, and maybe have one day of 32-33C.

Another surprising fact was that, despite the prevailing heat and drought in 97-98, there were still cold, squally changes with hail and thunder at times.

It’s too early to tell how this El Niño will pan out. But it’s possible this may be the summer in which New Zealand’s highest temperature of 42.4C, set in Rangiora on February 7, 1973, is threatened.

What we can say with almost certainty is there will be dryness. But how hot and settled, or cold and stormy, it is remains to be seen.