Island Climate Update 18 - March 2002

Tropical Cyclone Update
Five tropical cyclones so far
Five tropical cyclones have occurred so far this season, which is well below average at this stage. 'Claudia' developed west of New Caledonia at 21°S 157°E on 11 February, and was the first this season to form west of the date line, reaching hurricane force (with estimated maximum sustained winds of about 140 km/h) as it tracked southeast to pass north of Norfolk Island from 12-13 February. A new tropical cyclone, 'Des' developed northwest of New Caledonia near 19°S 161°E on 6 March.

Forecast validation
Forecast period: December 2001 to February 2002
The trade winds were expected to remain slightly enhanced across the central Pacific, pushing the SPCZ a little further south than usual. Resulting rainfall was expected to be below average in Tokelau, Eastern Kiribati, Samoa, the Northern Cook Islands, and the Marquesas Islands of French Polynesia. Average rainfall was expected in other parts of French Polynesia and from Fiji to Tuvalu.

ENSO and Sea Surface TEmperatures
Much warmer than average seas across the whole of the tropical Southwest Pacific
A warm ENSO event is possible later this year
In the tropical Southwest Pacific, a very extensive area of much warmer than usual water at the surface (at least 1.0°C above average) extends from the Coral Sea right across to the region well east of Pitcairn Island, encompassing most islands between 15 and 25°S. The warmest surface waters (30-31°C) surround the Solomon Islands and an area further east between Tuvalu and Samoa.

An overview of the present climate in the tropical South Pacific Islands, with an outlook for the coming months, to assist in dissemination of climate information in the Pacific region.
Number 18 – 10 March 2002
February’s Climate: An extensive area of enhanced convection occurred from Papua-New Guinea to Eastern Kiribati, with another convective band associated with a southward displacement of the SPCZ extending from Tuvalu southeast through Tonga. Rainfall was well above average in parts of Western Kiribati, Fiji, southern Tonga, and parts of southern French Polynesia.

Climate developments in February 2002
Active convection over equatorial waters about and west of the date line
Low rainfall in the Northern Cook Islands and much of French Polynesia
An extensive area of enhanced convection occurred over equatorial waters about and west of the date line, from Papua-New Guinea to Eastern Kiribati, with another convective band associated with a southward displacement of the SPCZ extending from Tuvalu southeast across Fiji and Tonga.

Rainfall outlook for March to May 2002
Below average rainfall in equatorial latitudes from Tokelau east, mainly average rainfall in other areas; trending towards above average in Western Kiribati, and Fiji across to Niue.
The trades were again slightly stronger in February east of the dateline, and weaker to the west. The SPCZ was located from east of the Solomon Islands, across Fiji and Tonga: displaced south of its normal position. Rainfall is projected to be above average in Niue, and average to above average from Fiji across to Tonga, and in Western Kiribati.

Sources of South Pacific rainfall data
This bulletin is a multi-national project with important collaboration from the following Pacific nations:
American Samoa
Australia
Cook Islands
Fiji
French Polynesia
Kiribati
New Caledonia
New Zealand
Niue
Papua New Guinea
Pitcairn Island
Samoa
Solomon Islands
Tokelau
Tonga
Tuvalu
Vanuatu
Requests for Pacific island climate data should be directed to the Meteorological Services concerned.
Acknowledgements
This bulletin is made possible with financial support from the New Zealand Agency for International Development (NZAID), Wellington, New Zealand, wi