Climate Update 64 - October 2004

October

Climate

River flows

Soil moisture

Three-month outlook

Checkpoint

Backgrounder

Backgrounder

Backgrounder
Climate forecasting with traditional Māori knowledge
Darren NT King & Apanui Skipper
Te Kūwaha – Māori Research Unit (NIWA)
Ever since Māori first arrived in New Zealand, the ability to understand and adapt to local climate has been vital to their survival. Through interacting with local environments over the centuries Māori have developed an extensive knowledge of climate, and the lessons learnt have been incorporated into traditional and modern practices of agriculture, fishing, medicine, education, and conservation.

Checkpoint

Outlook and outcome – July 2004 to September 2004
Atmospheric circulation over New Zealand was more southwesterly than expected.
Normal rainfall was predicted for most of New Zealand. The outcome was drier than normal conditions in parts of the north and west of the North Island, Kaikoura, and Otago, and above average rain in Bay of Plenty, the southern North Island, and parts of Southland.
Air temperatures were lower than predicted across the country.

Climate

New Zealand Climate
Third cool month in a row
September was the third consecutive month with below average temperatures. Much of the North Island was 0.5 to 1.0 °C below average.
Rainfall was well below average in northern New Zealand and Hawke’s Bay.

October

Climate Update is a summary each month of New Zealand’s climate, including soil moisture and river flows.
October 2004 – Number 64
September’s climate: September rainfall well below normal in Northland, above normal in central New Zealand and Southland.

Three-month outlook

The outlook for October 2004 to December 2004
Mean sea-level pressures are expected to be lower than normal to the south of New Zealand, with more west to southwest wind flow than usual over the country for the remainder of 2004. Sea surface temperatures are likely to remain slightly below average around New Zealand over the next three months.
Temperatures are expected to be average or below average in the north and west of the North Island, and near average elsewhere.

River flows

River flows
Low flows in the north and east
Streamflows were below normal in the northern North Island, and mid, and South Canterbury; above normal in the southern North Island, Southland, and parts of Taranaki, Tasman, and Buller; and normal elsewhere.
 

Soil moisture

Dry spots in the north and east
Soil moisture levels in eastern Northland, along the Marlborough-Kaikoura coast, and in parts of inland Otago were lower than average at the end of September. Soils elsewhere remained near field capacity during the month.
 
Soil moisture deficit in the pasture root zone at the end of September (right) compared with the deficit at the same time last year (centre) and the long-term end of September average (left). The analysis is done for an average soil type where the available water capacity is taken to be 150 mm.