In the northern moiety of the dry region the temperatures are of course much more severe than in the southern, for, as we have seen, the hottest portion of Australia lies between the Peak Hill and Pilbara Gold-Fields. The evaporation is therefore much greater here than in the southern gold-fields—an important factor in connexion with the water supply of these centres. (Compare Wiluna and Coolgardie in the following table):—
Evaporation Data.
| Station. | Years. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Total Evaporation. | Annual Rainfall. |
| Carnarvon | 4 | 14.6 | 11.9 | 10.8 | 8.3 | 5.3 | 4.3 | 5.0 | 6.4 | 7.5 | 10.0 | 11.8 | 13.4 | 109.3 | 9.05 |
| Wiluna | 8 | 21.4 | 17.7 | 15.7 | 10.6 | 7.3 | 4.7 | 5.0 | 6.7 | 9.5 | 14.3 | 18.3 | 21.7 | 152.9 | 9.76 |
| Coolgardie | 14 | 13.1 | 10.6 | 9.3 | 6.2 | 3.8 | 2.5 | 2.5 | 3.5 | 5.3 | 7.5 | 10.3 | 13.1 | 87.74 | 9.09 |
N.B.—Coolgardie, 36″ tank with water jacket. Carnarvon and Wiluna, 8″ dishes with small water jacket. No satisfactory determination of the factor required to relate evaporation results from these different experiments has yet been made, but it is possible that the 8″ dish will give the results from 5 to 15 per cent. in excess of those of the tank.
In the following tables, the meteorological data for a number of typical stations in the dry region are given:—
| Station. | State. | Height. | Description. |
| Feet. | |||
| Carnarvon | Western Australia | 15 | The driest costal town in Australia. |
| Nullagine | Western Australia | 1,265 | Inland town (150 miles from coast). Characterized by intense summer heat. |
| Peak Hill | Western Australia | 1,930 | Inland town (300 miles from coast). |
| Coolgardie | Western Australia | 1,389 | On the south-east boundary of the dry region (330 miles from coast). |
| Alice Springs | Northern Territory | 2,000 | In the Central Highlands (600 miles from coast) |
| William Creek | South Australia | 250 | Near Lake Eyre (250 miles from coast) |
| Broken Hill | New South Wales | 1,000 | Near the south-west boundary (200 miles from coast) |
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