There is now no doubt. The El Nino weather event that’s been predicted for months is occurring and is expected to be as strong as or stronger than that of 1997/8. That event in its turn eclipsed the El Nino of 1982/3: the one that made the terms El Nino (Christ child) and his sister (La Nina) household names and was one of the strongest since records were first kept in 1876 of the Southern Oscillation Index (SOI) – the scientific measurement of barometric pressure and sea surface temperatures between the east and west Pacific that determines these far reaching weather events.
A clever NASA oceanographer has dubbed the current El Nino as “Godzilla” after the monster in the movie of the same name. And not without reason. According to the Australian Bureau of Meteorology’s latest ENSO report www.bom.gov.au/climate/enso/ issued on August 18, the ocean and atmosphere in the tropical Pacific are reinforcing each other to produce a mature El Nino which will probably extend well into 2016. Sea surface temperatures are more than +2 C warmer than usual in the tropical eastern Pacific with warm anomalies of more than + 1 C extending westwards to around 170 degrees east longitude. All computer models suggest further warming as the trade winds remain consistently weaker keeping warm water in the east and the SOI strongly negative. As at August 16, 2015 its 30 day average was – 20.3 which is roughly what it was in August 1997 albeit with a longer decline in 2014/5 than was seen then.
Besides the drought conditions that El Nino events inevitably bring to the western Pacific, including to Vanuatu – about which Vanuatu Met Services’ latest climate update warns see www.meteo.gov.vu/climate – the two major events of 1982/3 and 1997/8 also brought exceptionally long cyclone seasons and the most cyclones in records kept since 1950: 14 and 16 respectively. With super cyclone Pam still fresh in our minds, it’s timely to consider what may be in store for the coming season should it resemble the stronger of the two.
In 1982 cyclone Joti formed northeast of Vanuatu on October 31. The last cyclone, William, dissipated on April 23, 1983. The 1997/8 season was even longer. On October 6, 1997 almost a month before the official start of cyclone season, cyclone Lusi began forming in the same area as Joti had 15 years earlier. It was named on October 10. After tracking through the alphabet of cyclone names all the way to Z and then starting again, the last cyclone, Bart, hung around until May 5, 1998. That season was also remarkable for there being three simultaneous severe cyclones: Ron, Susan and Katrina, on January 7, 1998. In both seasons many cyclones occurred east of the dateline and even in French Polynesia which had been spared any since a previously very strong El Nino in 1905/6.
West of the dateline a seemingly never ending succession of lows, tropical depressions and cyclones kept boat people on their toes. For us that meant hunkered down in Le Carenage a cyclone hole in Baie du Prony in South Grande Terre New Caledonia for most of the season. Not that it is ever bad being surrounded by uninhabited wilderness, fresh running streams and cascades and walking tracks to die for – but it seemed every time we poked our noses out or sailed the 40 miles back to Noumea for supplies another low would form and we’d be heading south again. I imagine the weather caused some frayed nerves among the landlubbers in New Caledonia and Vanuatu as well.
After Lusi there was a break until the end of October 1997 when two tropical depressions formed, one east and one west of the dateline. The latter turned into cyclone Martin in which 28 people died and nearly US$ 18 million damage was caused in the Cook Islands and French Polynesia.
Next came Nute, named on November 19 when north of Vanuatu. It reached hurricane strength as it moved south-west to the middle of the Coral Sea before recurving and dissipating south of New Caledonia.
For the rest of November every weather forecast included at least one tropical disturbance sometimes three as on November 24 when they stretched between 166 E and 158 W.
The one furthest east turned into cyclone Osea that night and rapidly intensified to 965 hPa clobbering Mopelia and Bora Bora Islands in French Polynesia with winds of 80 knots. Later in the week Nadi Tropical Cyclone Warning Centre stopped forecasting individual lows and depressions and lumped the lot together saying ‘there is a possibility of multiple centres along the Convergence Zone with clockwise winds to 20 knots and gusts to 35 knots in thunderstorms”.
They had to be more specific on November 30 though, when one of these became more defined and hovered around 167 W for several days. Of interest to meteorologists was that at the same time typhoon Paka with storm force winds was forming directly opposite on the other side of the equator. Paka began moving west and allowed more energy to accumulate in the low south of the equator. Christened Pam on Sunday December 7 it intensified to 60 knots but couldn’t sustain the energy and trundled off to the south east.
Paka though continued west-northwest to hit Guam on December 17 with sustained winds of 160 knots gusting to 200 knots, the then highest ever recorded.
The lead up to Christmas was comparatively quiet but then suddenly at New Year a depression near 171 W began intensifying. It would soon be named Ron while two other depressions in the north-eastern Coral Sea became Susan and Katrina. By January 7 Susan (affecting Vanuatu and Fiji) and Ron (affecting Samoa, Wallis and Futuna and Tonga) had both intensified to 900 hPa with 125 knot sustained winds while Katrina, named by Brisbane, couldn’t make up her mind what to do or which way to move. After moving erratically for over three weeks she eventually dissipated over North Queensland. Meanwhile ex cyclone Sid (named by Darwin) moved south from the Gulf of Carpentaria and dumped half a meter of rain in the Townsville area.
This time had also been very wet in New Caledonia, prompting the comment in the ship’s log “a dry day in Carenage!”
Continuing disturbances and depressions with plenty of “998 hPa’s” in the forecasts brought strong winds to New Caledonia right through until the end of February and cyclones Tui, Ursula and twins Wes and Veli formed east of the dateline. The last brought very heavy rain to French Polynesia where ten people were killed in landslides on Taha’a Island.
Ten gorgeous light wind days then lulled us all into a ‘maybe it’s finished’ frame of mind.
But, sparked by a northeast moving front a low began to develop northwest of Banks and Torres. It became cyclone Yali on March 21 reaching 70 knots while just to the west of Vanuatu. It then turned southwest, moving between the Isle of Pines and Grande Terre, New Caledonia. Just when we hadn’t bothered to run for Carenage and instead found ourselves on a lee shore in Baie de l’Orphelinat in Noumea. Not pretty, but at least our anchor held. Many others’ didn’t and they finished up on the beach.
Last in the alphabet but not in the season was Zuman which began on March 30 north east of Vanuatu, crossed Santo with 80 knot winds and then ran down between Grande Terre and the Loyalty Islands.
Alan and Bart started the alphabet off again. They were of little concern to us but the Cook Islands and French Polynesia copped it again and there were more landslides on Taha’a.
All in all it was a season to remember, not particularly fondly.With now less than two months to go before the anniversary of Lusi in 1997 it’s time for preparations. Better to expect the worst and be relieved when it doesn’t happen than be taken by surprise if it does.Then there are the mangoes.In 1997 the trees were in full flower in May. In Freshwota next to ABM this week a tree not only has flowers (normal now) but also big mango fruits already! EEK!