Map Construction

Construction technique:

This map is based on the SEASONAL RAINFALL ZONES chart, (from the AUSTRALIAN CLIMATE ATLAS published by the Bureau in 1975), except that the Tasmanian climate zones have been re-analysed. The SEASONAL RAINFALL ZONES CHART shows considerably more detail, with a climate zone classification based on annual rainfall, seasonal incidence of rainfall and altitude. Seasonal incidence is determined from the ratio (greater/lesser) of the median rainfalls: November - April (summer) and May - October (winter).

Climate zone definitions:

Dominant summer rainfall zone:

Seasonal ratio > 3.0; median annual rainfall >= 350 mm.

Arid, mostly summer rainfall zone (1):

3.0 > seasonal ratio > 1.3 (in the southern part of the zone, see footnote); median annual rainfall < 350 mm.

Mostly summer rainfall zone:

3.0 > seasonal ratio > 1.3; median annual rainfall >= 350 mm.

Arid, mostly uniform rainfall zone (2):

Seasonal ratio < 1.3 (in most of the zone, see footnote); median annual rainfall < 350 mm.

Uniform rainfall zone:

Seasonal ratio < 1.3; median annual rainfall >= 350 mm.

Mostly winter rainfall zone:

3.0 > seasonal ratio > 1.3; median annual rainfall >= 350 mm.

Dominant winter rainfall zone:

Seasonal ratio > 3.0; median annual rainfall >= 350 mm.

(1) Summer rainfall dominates (seasonal ratio > 3.0) in the northern part of the zone

(2) mostly winter rainfall along the southern edge of the zone