Climate Update 80 - February 2006

February

January's climate

Global setting & climate outlook

Feature article

Feature article

Stratosphere holds potential for predicting NZ climate

The layers of the atmosphere shown schematically. The weather we experience is influenced by the overlying stratospheric layer. Note that the Earth’s protective ozone layer is concentrated in the stratosphere.

How the atmosphere behaves from one day to the next – the weather – can be predicted only a few days in advance. That’s because weather patterns are short-lived; cyclones and anticyclones form and decay over just a few days.

February

A monthly newsletter from the National Climate Centre.
February 2006 – Number 80
January – cool in the south and mostly warm in the north. High rainfall and stream flows in some areas.
Outlook for February to April – lighter than normal westerlies; temperatures average or above; rainfall average or below, with low streamflows likely in the southwest North Island and eastern South Island.
In this issue

January's climate
Global setting & climate outlook
Feature article - Stratosphere holds potential for predicting NZ climate

Cover image
Sunflowers near Richmond.

January's climate

New Zealand climate in January 2006

Rainfall (click to enlarge).

Temperature (click to enlarge).

Western South Island temperatures plummeted in January, after one of the warmest Decembers on record. Mean January temperatures were up to 1.5 °C below average in parts of Westland and Fiordland.

Global setting & climate outlook

Global setting
Weak La Niña

Difference from average global SST (click to enlarge).

Monthly SOI values (click to enlarge).

The state of the tropical Pacific Ocean and atmosphere is now characteristic of weak La Niña conditions. Trade winds across the equatorial region of the Pacific are stronger than normal, and convection is enhanced over northern Australia and Indonesia.
The Southern Oscillation Index (SOI) rose above +1 in January, from a neutral value in December (-0.1). The 3-month mean SOI is still in the neutral range.