The Climate and Weather of Australia/Chapter 8
VIII.—CHIEF CLIMATIC REGIONS.
Our study of the chief weather elements has shown us that Australia has not one general climate, but contains within its vast area several types of climate. They may be classified according to many factors; such as amounts of rainfall, seasons of rainfall dominant winds, topography, &c., &c. A combination of the first two criteria seems to furnish the best primary division, while the less important factors will determine the secondary subdivision.
The proposed scheme may be tabulated as follows:
These subdivisions are shown in Fig. 58.
Monsoon Region.
This comprises the whole of Australia north of the Tropic of Capricorn, together with Southern Queensland and the north of New South Wales, The heaviest rains are in January and February. They are directly due to the indraught caused by the heating of the centre of the continent. This leads to the formation of a locus of low pressure (monsoonal depression) in Northern Australia, and the ascending winds are cooled and deposit their water vapour in heavy rain storms and thunder showers.
Over the greater portion of the area the winter is usually quite dry, and practically the whole of the rain falls in three or four months. But in the east, owing to two special controls, the rain is much more abundant and uniform. Along the Queensland coast the land rises to considerable heights, and there is a very permanent onshore wind the South-east Trade. This leads to a rainfall of over an inch each month in the winter, while the rest of the summer rain region is receiving nothing. It seems worth while therefore to separate this eastern fringe as a subdivision of the summer rain (or monsoon) region.
Meteorological data are given in the following table for type stations in this region:
Station. | State. | Height. | Description. |
Feet. | |||
Broome | Western Australia | 63 | A coastal town, subject to hurricanes. |
Hall's Creek | Western Australia | 1,225 | An inland mining township (200 miles from coast) |
Darwin | Northern Territory | Capital of Northern Territory (on the coast) | |
Daly Waters | Northern Territory | An inland settlement on Overland Telegraph (300 miles from coast) | |
Cloncurry | Queensland | 696 | An inland town (200 miles south from Gulf of Carpentaria) |
Charleville | Queensland | 975 | A town in South Queensland (300 miles from the Pacific coast) |
[1]Harvey Creek | Queensland | A coastal town with heaviest rainfall in Australia (25 miles south of Cairns) | |
Brisbane | Queensland | 137 | Capital of Queensland; in the south-east, about 10 miles up the Estuary |
Types of the Summer Rain Region.
Pressure.[2]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Broome, Western Australia | 29.721 | 29.731 | 29.758 | 29.847 | 29.920 | 29.950 | 29.962 | 29.951 | 29.908 | 29.860 | 29.792 | 29.748 | 29.846 | 15 |
Hall's Creek, Western Australia | 29.720 | 29.737 | 29.787 | 29.890 | 29.982 | 30.012 | 30.016 | 29.982 | 29.916 | 29.853 | 29.788 | 29.742 | 29.869 | 12 |
Darwin, Northern Territory | 29.701 | 29.710 | 29.746 | 29.796 | 29.851 | 29.881 | 29.897 | 29.895 | 29.864 | 29.829 | 29.780 | 29.727 | 29.806 | 31 |
Cloncurry, Queensland | 29.714 | 29.756 | 29.823 | 29.948 | 30.042 | 30.077 | 30.082 | 30.076 | 30.009 | 29.934 | 29.866 | 29.783 | 29.926 | 12 |
Charleville, Queensland | 29.815 | 29.874 | 29.938 | 30.074 | 30.169 | 30.181 | 30.170 | 30.165 | 30.096 | 30.041 | 29.950 | 29.857 | 30.028 | 9 |
Cairns, Queensland | 29.752 | 29.805 | 29.826 | 29.923 | 30.007 | 30.020 | 30.028 | 30.048 | 30.023 | 30.003 | 29.930 | 29.840 | 29.934 | 9 |
Brisbane, Queensland | 29.898 | 29.927 | 29.988 | 30.083 | 30.138 | 30.105 | 30.108 | 30.138 | 30.077 | 30.046 | 30.003 | 29.923 | 30.036 | 26 |
Types of the Summer Rain Region.
Temperature.[3]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ||
Broome, Western Australia | 85.9 | 85.4 | 85.4 | 83.1 | 76.4 | 71.2 | 70.3 | 72.4 | 77.0 | 81.0 | 84.6 | 85.9 | 79.8 | 16 |
Hall's Creek, Western Australia | 87.0 | 85.6 | 82.6 | 77.7 | 70.8 | 65.6 | 64.7 | 69.0 | 76.2 | 83.4 | 86.9 | 87.0 | 78.0 | 14 |
Darwin, Northern Territory | 84.0 | 83.5 | 84.2 | 84.2 | 81.8 | 77.3 | 77.2 | 79.4 | 83.0 | 85.2 | 85.7 | 85.3 | 82.6 | 37 |
Daly Waters, Northern Territory | 86.9 | 85.5 | 83.8 | 80.2 | 74.7 | 70.1 | 68.6 | 72.7 | 79.8 | 86.1 | 88.2 | 88.1 | 80.4 | 27 |
Cloncurry, Queensland | 87.3 | 85.0 | 83.1 | 77.8 | 71.0 | 64.2 | 61.5 | 67.0 | 72.8 | 82.5 | 85.2 | 88.0 | 77.1 | 12 |
Charleville, Queensland | 82.9 | 80.7 | 76.1 | 68.7 | 60.1 | 53.7 | 51.1 | 56.6 | 62.8 | 71.6 | 77.5 | 80.4 | 68.5 | 10 |
Cairns, Queensland | 81.7 | 81.1 | 79.7 | 77.1 | 73.6 | 70.5 | 69.8 | 70.0 | 73.0 | 76.2 | 78.5 | 81.3 | 76.0 | 8 |
Brisbane, Queensland | 77.2 | 76.5 | 74.3 | 70.2 | 64.4 | 60.0 | 58.0 | 60.5 | 65.1 | 69.8 | 73.3 | 76.4 | 68.8 | 26 |
Types of the Summer Rain Region.
Rainfall.
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Total for Year. | No of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Broome, Western Australia | 4.96 | 6.35 | 3.77 | 1.35 | .41 | 1.22 | .27 | .04 | .08 | .03 | .93 | 3.55 | 22.96 | 23 |
Hall's Creek, Western Australia | 5.28 | 4.73 | 2.92 | 1.18 | .41 | .24 | .25 | .12 | .16 | .59 | 1.36 | 3.43 | 20.67 | 22 |
Darwin, Northern Territory | 15.27 | 13.05 | 9.70 | 4.50 | .75 | .16 | .07 | .11 | .48 | 2.12 | 5.21 | 10.30 | 61.72 | 43 |
Daly Waters, Northern Territory | 6.12 | 6.71 | 5.02 | 1.04 | .15 | .34 | .07 | .15 | .29 | .83 | 2.15 | 4.08 | 26.95 | 40 |
Cloncurry, Queensland | 4.94 | 5.07 | 2.60 | .86 | .42 | .44 | .46 | .10 | .44 | .46 | 1.13 | 2.99 | 19.91 | 23 |
Charleville, Queensland | 2.49 | 3.14 | 3.23 | 1.46 | 1.41 | 1.33 | .94 | .58 | .81 | 1.29 | 1.34 | 2.26 | 20.28 | 23 |
Harvey Creek, Queensland | 30.87 | 22.18 | 32.19 | 22.20 | 13.20 | 7.98 | 4.22 | 5.42 | 3.68 | 3.81 | 8.10 | 11.73 | 165.58 | 16 |
Brisbane, Queensland | 6.66 | 6.63 | 6.20 | 3.64 | 2.92 | 2.62 | 2.33 | 2.35 | 2.05 | 2.78 | 3.65 | 5.12 | 46.95 | 61 |
Dry Region.
This is bounded somewhat arbitrarily by the 10-in. annual isohyet. Two areas within the tract as plotted have more than 10 inches—in the north-east, the highlands of the MacDonnell Ranges, and in the north-west the Peak Hill Gold-field.
These two relatively wet areas may be related with the two favorite paths of the tropical "lows"; which often curve southward and south-eastward over Pilbara and Western Queensland respectively.
Owing to lack of information the northern boundary of the dry region cannot be accurately plotted, so that the line given—from Winning Pool to Barrow Creek—will, no doubt, need considerable revision later. Although the scattered rains of the north fall chiefly in January, and of the south in May and June, this variation does not determine the type of vegetation which is almost wholly controlled by absence of rain (xerophilous), and not by the season when it falls. The dry region, which consists mainly of an undulating tableland 1,000-3,000 feet high, forms therefore a united whole.
If the isohyets for 0.5 inches are plotted in each month (not shown in Figs. 39 to 50), the MacDonnell Ranges are seen to form an "oasis" in the arid region. In May, June, October, and November, when the districts not only south but east (Sturt's Desert, &c.) are receiving less than half-an-inch this region of uplands (3,000 feet) is favoured by more rainfall. Possibly the Musgrave Ranges—which are said to reach 5,000 feet (Mt. Woodroffe, 5,230 feet), also benefit in a similar degree, but no data are available.
The driest region so far furnished with rain-gauges lies east and north-east from Lake Eyre, where less than 5 inches is the average annual rainfall. This minimum rainfall is coincident with the lowest elevation, Lake Eyre being actually below sea-level, 39 feet.
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) |
Types of the Dry Region.
Pressure.[4]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Carnarvon, Western Australia | 29.790 | 29.798 | 29.848 | 29.947 | 30.019 | 30.038 | 30.070 | 30.069 | 30.030 | 29.990 | 29.912 | 29.822 | 29.944 | 15 |
Nullagine, Western Australia | 29.690 | 29.711 | 29.787 | 29.906 | 29.992 | 30.042 | 30.056 | 30.024 | 29.944 | 29.874 | 29.772 | 29.704 | 29.875 | 13 |
Peak Hill, Western Australia | 29.702 | 29.726 | 29.808 | 29.929 | 30.023 | 30.064 | 30.079 | 30.051 | 29.968 | 29.898 | 29.792 | 29.710 | 29.896 | 14 |
Coolgardie, Western Australia | 29.866 | 29.900 | 29.937 | 30.106 | 30.096 | 30.111 | 30.024 | 30.103 | 30.024 | 29.974 | 29.913 | 29.858 | 29.999 | 15 |
Alice Springs, Northern Territory | 29.708 | 29.736 | 29.846 | 29.984 | 30.072 | 30.106 | 30.122 | 30.056 | 29.972 | 29.887 | 29.804 | 29.742 | 29.920 | 30 |
Broken Hill, New South Wales | 29.875 | 29.905 | 29.962 | 30.120 | 30.154 | 30.163 | 30.114 | 30.142 | 30.042 | 30.030 | 29.934 | 29.860 | 30.025 | 5 |
Types of the Dry Region.
Temperatures.[5]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ||
Carnarvon, Western Australia | 79.8 | 80.6 | 79.4 | 74.7 | 67.9 | 62.7 | 60.6 | 62.6 | 65.6 | 69.0 | 73.0 | 76.9 | 71.1 | 15 |
Nullagine, Western Australia | 89.8 | 88.6 | 84.2 | 77.3 | 68.5 | 61.1 | 59.3 | 63.9 | 71.0 | 78.2 | 85.8 | 88.8 | 76.4 | 14 |
Peak Hill, Western Australia | 87.6 | 86.2 | 82.1 | 74.0 | 63.8 | 56.5 | 54.7 | 58.9 | 65.0 | 71.8 | 80.3 | 86.2 | 72.3 | 14 |
Coolgardie, Western Australia | 77.5 | 76.0 | 71.6 | 65.4 | 57.6 | 52.3 | 50.8 | 53.4 | 58.4 | 63.6 | 70.9 | 76.2 | 64.5 | 16 |
Alice Springs, Northern Territory | 84.0 | 82.3 | 76.9 | 68.0 | 59.7 | 54.2 | 52.5 | 58.5 | 65.5 | 73.6 | 79.5 | 82.5 | 69.8 | 34 |
William Creek, South Australia | 82.7 | 82.5 | 76.1 | 67.2 | 59.2 | 53.9 | 52.2 | 56.2 | 62.4 | 70.3 | 77.1 | 81.4 | 68.4 | 24 |
Broken Hill, New South Wales | 78.4 | 77.9 | 71.8 | 63.9 | 56.6 | 51.0 | 49.2 | 52.8 | 58.4 | 65.8 | 73.0 | 76.6 | 64.6 | 21 |
Types of the Dry Region.
Rainfall.
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Total for Year. | Number of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Carnarvon, Western Australia | .30 | .70 | .45 | .52 | 1.29 | 2.83 | 1.87 | .63 | .25 | .08 | .04 | .09 | 9.05 | 30 |
Nullagine, Western Australia | 2.67 | 2.02 | 2.60 | 1.04 | .55 | 1.13 | .70 | .46 | .01 | .00 | .39 | 1.17 | 12.74 | 15 |
Peak Hill, Western Australia | 1.39 | 1.06 | 1.25 | 1.23 | 1.01 | 1.35 | .86 | .62 | .20 | .14 | .19 | .43 | 9.73 | 15 |
Coolgardie, Western Australia | .37 | .69 | .65 | .64 | 1.35 | 1.18 | .87 | .90 | .61 | .69 | .52 | .62 | 9.09 | 20 |
Alice Springs, Northern Territory | 1.68 | 1.73 | 1.24 | .90 | .60 | .57 | .46 | .40 | .41 | .72 | .90 | 1.32 | 10.93 | 39 |
William Creek, South Australia | .55 | .41 | .77 | .45 | .45 | .69 | .25 | .29 | .45 | .33 | .42 | .35 | 5.41 | 39 |
Broken Hill, New South Wales | .76 | .84 | .63 | .72 | .87 | 1.41 | .66 | .97 | .68 | .84 | .71 | .80 | 9.89 | 24 |
Intermediate Region of Uniform Rains.
In our description of the monthly rainfall we saw that the distribution areas were shaped like crescents. The summer rain crescent includes Northern Australia and South-eastern Australia; the winter rain crescent includes South-western Australia and South-eastern Australia. In other words, the two crescents do not meet in the north-west—so far as any but light rains are concerned—but overlap in the south-east. Hence the central coastal aridity in Western Australia, and the region of uniform monthly rainfall in Eastern Australia.
The latter region is a somewhat triangular area reaching from Wilcannia east to the coast at Port Macquarie, and south-east to Albury and thence to Melbourne. A reference to the following tables shows that Dubbo is the typical station, for, as already noted, it has just under 2 inches of rainfall each month of the year. Cobar and Wilcannia to the north-west and Goulburn and Delegate to the south-east are also on the axis of uniformity. To the north-east the summer rains grow proportionately greater—though a considerable amount of rain falls all the winter. To the south-west the June maximum becomes very evident—and West or South-west from the Grampians the winter rainfall is more than double that of summer.
Fig. 59.
Anticyclone causing south-easterly winds and rain in coastal districts of New South Wales.
Furthermore, along the coast from Port Stephens to Ulladulla is an "enclave" of autumn rains. This includes Sydney, and forms a narrow coastal strip with heavy rains in February, March, April, May, and June, and moderate rains in the remaining months. An explanation of this is suggested in the following paragraphs, based on conditions in 1912.
During these autumn months the anticyclones move along latitudes of about 35° S. (In midwinter this path is along 28° and in midsummer along 42°. In Spring the paths are much the same as in autumn.)
About once a week during the autumn months of 1912 this coastal strip experienced rains, while the rest of New South Wales was dry. This rain generally accompanied south-east on-shore winds, in the front and north of a high, as shown in Fig. 59. Out of nineteen examples of this type of rain distribution, in autumn, 1912, no less than fifteen occurred when the "high" was centred about the Bass Straits. (Roughly, between Mt. Gambier and Gabo.)
Meteorological data for the following stations is given in the tables:—
Town. | State. | Height. | Distance from Coast. |
Description. |
Feet. | Miles. | |||
Wilcannia | New South Wales | 267 | 300 | An inland town in the Western Plains |
Dubbo | New South Wales | 870 | 200 | On the western slopes of the Divide |
Newcastle | New South Wales | .. | .. | Coastal town near boundary of uniform regions and autumn rains |
Sydney | New South Wales | 146 | .. | Capital, on the coast, with autumn maximum |
Moruya | New South Wales | .. | .. | Coastal town in the south |
Yass | New South Wales | 1,650 | 100 | On the western slopes of the Divide |
Kiandra | New South Wales | 4,640 | 100 | Highest town in Australia |
Sale | Victoria | .. | .. | Coastal town in drier region of Gippsland |
Melbourne | Victoria | 115 | .. | Capital, at south-west corner of uniform region |
Hobart | Tasmania | 160 | .. | Capital, on south-east of island |
Types of the Uniform Rain Region.
Pressure.[6]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Wilcannia, New South Wales | 29.888 | 29.920 | 30.016 | 30.124 | 30.177 | 30.153 | 30.172 | 30.147 | 30.097 | 30.033 | 29.984 | 29.913 | 30.052 | 30 |
Dubbo, New South Wales | 29.899 | 29.935 | 30.017 | 30.117 | 30.173 | 30.135 | 30.153 | 30.144 | 30.079 | 30.020 | 29.958 | 29.896 | 30.044 | 29 |
Newcastle, New South Wales | 29.915 | 29.961 | 30.038 | 30.095 | 30.107 | 30.082 | 30.109 | 30.103 | 30.041 | 30.002 | 29.974 | 29.905 | 30.028 | 50 |
Sydney, New South Wales | 29.930 | 29.975 | 30.051 | 30.108 | 30.116 | 30.080 | 30.116 | 30.105 | 30.045 | 30.003 | 29.971 | 29.916 | 30.035 | 51 |
Moruya, New South Wales | 29.908 | 29.966 | 30.031 | 30.056 | 30.092 | 30.033 | 30.069 | 30.086 | 29.994 | 29.960 | 29.949 | 29.881 | 30.002 | 35 |
Sale, Victoria | 29.879 | 29.961 | 30.018 | 30.050 | 30.098 | 30.057 | 30.042 | 30.054 | 29.949 | 29.918 | 29.931 | 29.897 | 29.988 | 17 |
Melbourne, Victoria | 29.913 | 29.962 | 30.037 | 30.101 | 30.106 | 30.078 | 30.097 | 30.067 | 29.996 | 29.965 | 29.952 | 29.896 | 30.014 | 55 |
Hobart, Tasmania | 29.849 | 29.942 | 29.969 | 29.971 | 30.016 | 29.974 | 29.951 | 29.954 | 29.866 | 29.856 | 29.821 | 29.819 | 29.916 | 28 |
Types of the Uniform Rain Region.
Temperatures.[7]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ||
Wilcannia, New South Wales | 81.4 | 79.9 | 74.0 | 65.4 | 57.7 | 52.3 | 50.0 | 53.9 | 60.2 | 68.2 | 74.8 | 79.4 | 66.4 | 27 |
Dubbo, New South Wales | 78.6 | 77.0 | 70.8 | 64.0 | 55.2 | 49.6 | 47.4 | 50.6 | 56.2 | 63.4 | 70.9 | 76.1 | 62.7 | 35 |
Newcastle, New South Wales | 73.0 | 72.4 | 71.0 | 66.4 | 60.3 | 56.0 | 54.0 | 56.2 | 60.4 | 64.9 | 68.6 | 71.5 | 64.6 | 47 |
Sydney, New South Wales | 71.6 | 71.0 | 69.2 | 64.5 | 58.6 | 54.3 | 52.3 | 54.8 | 58.8 | 63.4 | 67.0 | 70.0 | 63.0 | 54 |
Moruya, New South Wales | 69.0 | 68.6 | 67.2 | 63.2 | 57.1 | 53.0 | 51.8 | 53.6 | 56.9 | 60.2 | 63.9 | 66.4 | 60.9 | 37 |
Sale, Victoria | 65.8 | 66.5 | 63.1 | 58.4 | 53.2 | 49.1 | 47.5 | 49.9 | 52.4 | 56.0 | 61.4 | 64.0 | 57.3 | 16 |
Melbourne, Victoria | 67.5 | 67.3 | 64.7 | 59.5 | 54.1 | 50.3 | 48.4 | 51.0 | 54.0 | 57.5 | 61.3 | 64.5 | 58.3 | 57 |
Hobart, Tasmania | 62.4 | 62.4 | 59.5 | 55.1 | 50.4 | 46.8 | 45.3 | 47.7 | 50.8 | 53.9 | 57.5 | 60.3 | 54.3 | 42 |
Types of the Uniform Rain Region.
Rainfall.
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Total for Year. | No of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Wilcannia, New South Wales | 0.97 | 0.83 | 1.12 | 0.69 | 1.04 | 1.06 | 0.59 | 0.84 | 0.69 | 0.92 | 0.68 | 0.76 | 10.19 | 34 |
Dubbo, New South Wales | 2.13 | 1.87 | 1.82 | 1.78 | 1.87 | 2.01 | 1.67 | 1.83 | 1.86 | 1.55 | 1.78 | 2.02 | 22.19 | 41 |
Port Macquarie, New South Wales | 5.94 | 7.52 | 6.52 | 5.86 | 5.59 | 4.63 | 4.54 | 3.80 | 3.95 | 3.20 | 4.08 | 5.87 | 61.50 | 42 |
Sydney, New South Wales | 3.67 | 4.70 | 5.07 | 5.24 | 4.95 | 5.18 | 4.68 | 3.29 | 2.89 | 2.82 | 2.91 | 2.60 | 48.00 | 54 |
Moruya, New South Wales | 3.79 | 3.32 | 4.19 | 3.05 | 2.77 | 3.17 | 2.52 | 2.29 | 2.66 | 2.73 | 2.30 | 2.33 | 35.12 | 37 |
Kiandra, New South Wales | 4.09 | 3.15 | 4.05 | 4.37 | 5.27 | 8.70 | 6.55 | 5.95 | 6.86 | 6.61 | 4.90 | 3.95 | 64.45 | 40 |
Sale, Victoria | 2.05 | 1.52 | 1.96 | 1.90 | 1.83 | 2.33 | 1.88 | 2.01 | 2.30 | 2.20 | 2.14 | 2.12 | 24.24 | 24 |
Melbourne, Victoria | 1.85 | 1.74 | 2.18 | 2.32 | 2.15 | 2.11 | 1.86 | 1.81 | 2.35 | 2.64 | 2.20 | 2.30 | 25.51 | 57 |
Hobart, Tasmania | 1.80 | 1.45 | 1.65 | 1.80 | 1.91 | 2.22 | 2.10 | 1.83 | 2.14 | 2.24 | 2.50 | 1.93 | 23.57 | 70 |
Winter Rain Region.
This region consists of a belt along the south coasts of Australia. It may be subdivided into four sections on geographical grounds, though the meteorology does not differ so much as might be expected—
- (1) The south-west corner or Westralia Felix.
- (2) The Bight Littoral.
- (3) South Australian gulfs, Western Victoria, and the Riverina, New South Wales.
- (4) Tasmania (except the south-east).
In these areas there is a strong maximum of rainfall in June, especially in the west. Along the Australian Bight the area receiving more than 10 inches is extremely narrow. The effect of the Flinders Range, which lies athwart the westerly winds, in improving the rainfall of South Australia is very strikingly shown. Probably the long "Rift" Gulf immediately to the west also tends to increase the rainfall hereabouts. In Victoria, the rainfall becomes more uniform towards the north-east.
Along the west coast of Tasmania is a region, unique in Australia, where a superabundance of rain has almost prohibited settlement. There are practically no inhabitants in the south-west region, which is very rugged country covered with an almost impenetrable scrub. The rainfall reaches 115 inches per year on the highlands behind Macquarie Harbor, and is therefore only exceeded at Harvey Creek and neighbouring stations in North Queensland.
Around Hobart is a small region having a much more uniform rainfall with a spring maximum.
Meteorological data for the following stations will indicate how the elements vary in the Winter Rain Region:—
Town. | State. | Description. |
Perth | Western Australia | Capital. On Melville Water, 10 miles from ocean |
Esperance | Western Australia | On the south coast |
Eucla | Western Australia | On the coast, at the head of the Great Australian Bight |
Port Augusta | South Australia | On the coast, at the head of Spencer's Gulf |
Adelaide | South Australia | Capital. On the east coast of St. Vincent' Gulf |
Robe | South Australia | On the coast, in the south-east corner of South Australia |
Albury | New South Wales | In the Eastern Riverina, 542 feet above sea-level |
Launceston | Tasmania | On the Tamar Estuary, and 30 miles from the sea |
Types of the Winter Rain Region.
Pressure.[8]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Perth, Western Australia | 29.911 | 29.927 | 29.990 | 30.074 | 30.079 | 30.065 | 30.096 | 30.088 | 30.057 | 30.034 | 29.994 | 29.932 | 30.021 | 28 |
Esperance, Western Australia | 29.965 | 29.988 | 30.028 | 30.101 | 30.087 | 30.036 | 30.058 | 30.069 | 30.012 | 29.994 | 29.992 | 29.958 | 30.024 | 16 |
Eucla, Western Australia | 29.924 | 29.952 | 30.017 | 30.087 | 30.101 | 30.081 | 30.110 | 30.067 | 30.020 | 29.981 | 29.962 | 29.919 | 30.018 | 34 |
Port Augusta, South Australia | 29.874 | 29.906 | 29.998 | 30.102 | 30.137 | 30.119 | 30.148 | 30.105 | 30.038 | 29.983 | 29.945 | 29.887 | 30.020 | 33 |
Adelaide, South Australia | 29.915 | 29.952 | 30.038 | 30.118 | 30.125 | 30.099 | 30.131 | 30.100 | 30.038 | 29.996 | 29.973 | 29.920 | 30.034 | 56 |
Robe, South Australia | 29.933 | 29.978 | 30.037 | 30.095 | 30.127 | 30.055 | 30.050 | 30.058 | 29.987 | 29.963 | 29.971 | 29.926 | 30.015 | 23 |
Albury, New South Wales | 29.883 | 29.959 | 30.015 | 30.084 | 30.110 | 30.092 | 30.097 | 30.094 | 30.018 | 29.969 | 29.932 | 29.869 | 30.010 | 43 |
Cape, Otaway, Victoria | 29.918 | 29.965 | 30.031 | 30.043 | 30.075 | 30.030 | 30.040 | 30.011 | 29.967 | 29.940 | 29.934 | 29.899 | 29.988 | 46 |
Types of the Winter Rain Region.
Temperatures.[9]
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Year. | Number of Years. |
° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ° | ||
Perth, Western Australia | 73.6 | 74.2 | 71.2 | 66.4 | 60.4 | 56.2 | 55.0 | 56.0 | 57.9 | 60.9 | 65.4 | 70.6 | 64.0 | 16 |
Esperance, Western Australia | 68.6 | 69.2 | 66.7 | 63.2 | 58.8 | 55.1 | 53.6 | 54.7 | 56.8 | 59.4 | 63.0 | 66.3 | 61.2 | 16 |
Eucla, Western Australia | 70.9 | 71.2 | 69.3 | 66.1 | 60.9 | 55.9 | 54.3 | 56.3 | 59.3 | 62.7 | 65.9 | 69.3 | 63.5 | 35 |
Port Augusta, South Australia | 77.5 | 78.1 | 73.3 | 66.3 | 59.8 | 54.5 | 52.8 | 55.6 | 60.4 | 66.7 | 72.2 | 75.8 | 66.1 | 24 |
Adelaide, South Australia | 74.2 | 74.0 | 69.9 | 63.9 | 57.7 | 53.4 | 51.5 | 53.8 | 57.0 | 61.9 | 67.1 | 71.1 | 62.9 | 56 |
Robe, South Australia | 64.7 | 65.0 | 62.1 | 58.7 | 55.6 | 52.4 | 50.8 | 52.0 | 53.8 | 56.7 | 60.1 | 62.3 | 57.8 | 23 |
Albury, New South Wales | 76.2 | 74.3 | 69.3 | 60.4 | 52.1 | 47.8 | 45.9 | 49.0 | 53.8 | 60.1 | 66.9 | 71.9 | 60.7 | 43 |
Launceston, Tasmania | 64.1 | 64.5 | 60.6 | 55.5 | 49.1 | 46.5 | 44.1 | 46.3 | 50.2 | 53.9 | 58.2 | 62.0 | 54.8 | 18 |
Types of the Winter Rain Region.
Rainfall.
Station. | January. | February. | March. | April. | May. | June. | July. | August. | September. | October. | November. | December. | Total for Year. | No of Years. |
Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | Inches. | ||
Perth, Western Australia | .33 | .31 | .71 | 1.65 | 4.88 | 6.51 | 6.44 | 5.55 | 3.37 | 2.06 | .76 | .54 | 33.11 | 37 |
Esperance, Western Australia | .57 | .67 | .99 | 1.51 | 2.94 | 4.10 | 3.99 | 3.81 | 2.73 | 2.15 | .97 | .84 | 25.27 | 29 |
Eucla, Western Australia | .66 | .53 | .97 | 1.20 | 1.23 | 1.15 | .90 | .96 | .76 | .68 | .70 | .39 | 10.13 | 37 |
Port Augusta, South Australia | .54 | .46 | .75 | .82 | 1.15 | 1.18 | .69 | .86 | .93 | .88 | .69 | .51 | 9.46 | 53 |
Adelaide, South Australia | .73 | .60 | 1.06 | 1.87 | 2.74 | 3.10 | 2.66 | 2.50 | 1.95 | 1.74 | 1.15 | .94 | 21.04 | 74 |
Robe, South Australia | .80 | .65 | 1.19 | 1.91 | 3.04 | 4.01 | 3.95 | 3.62 | 2.15 | 1.69 | 1.07 | 1.01 | 24.69 | 52 |
Albury, New South Wales | 1.44 | 1.70 | 2.06 | 2.12 | 2.50 | 3.47 | 2.77 | 2.76 | 2.57 | 2.71 | 1.99 | 1.05 | 27.75 | 49 |
Launceston, Tasmania | 2.01 | 1.14 | 1.83 | 2.01 | 2.58 | 3.48 | 2.97 | 2.75 | 2.96 | 2.62 | 1.79 | 2.00 | 28.14 | 26 |
Comparison of Climatic Regions.
Each of the four or five main divisions of Australia which have been described in the foregoing can be paralleled by simlar regions in other parts of the world. These are briefly summarized in the following table (based on Herbertson and Koepper):—
Australian. | Extra-Australian. |
1. Summer rain region | Sudan, Brazil (like the wetter north portion); and South Siberia and Argentine (like the drier south-east portion) |
1a. North-east coast (trade wind region) | Florida, South China coast |
2. Dry region | Kalahari, Atacama, Sahara, Arizona |
3. Uniform rain region | Uruguay, Cape Colony (south-east) |
3a. Autumn maximum | Eastern U.S.A.,Natal, South-east Brazil |
4. Winter rain region | Cape Colony (west), Chili, California, and Mediterranean lands |
- ↑ N.B.—As pressure and temperature normals are not available for Harvey Creek those for Cairns have been substituted.
- ↑ Note.—The normals for Queensland stations refer to 9 a.m. observations only; the others are the means of the 9 a.m. and 3 p.m. observations.
- ↑ The means of maxima and minima.
- ↑ The normals for Broken Hill refer to 9 a.m. observations only; the others are the means of 9 a.m. and 3 p.m. observations.
- ↑ The means of maxima and minima.
- ↑ The normals for New South Wales stations and Hobart refer to 9 a.m. observations only; the Melbourne and Sale normals are the equivalent hourly means deduced from 9 a.m., and 3 p.m., and 9 p.m. observations.
- ↑ The means of maxima and minima, except for Sale, in which case the normals are the equivalent hourly means deduced from 9 a.m., 3 p.m., and 9 p.m. observations.
- ↑ The normals for Albury refer to 9 a.m. observations only; those for Cape Otway are equivalent hourly means deducted from 9 a.m., 3 p.m., and 9 p.m. observations, and for the other stations the mean of 9 a.m. and 3 p.m.
- ↑ The mean of maxima and minima.