II. The Climate of New Zealand

Transactions and Proceedings of the Royal Society of New Zealand, Volume 1, 1868, Unnumbered Page

II. The Climate of New Zealand Meteorological Statistics. The following Tables, which form the most reliable data for judging of the Climate of New Zealand, are extracted from the Reports of the Inspector of Meteorological Stations, for 1867, and are appended for the information of those to whom the above Report was not accessible. Table I—Mean Temperature of the Air in shade, recorded at the Chief Towns in the North and Middle Islands of New Zealand, from the earliest Observations to the end of 1867. Place. Mean Annual Temp. Mean Temp. for (Spring) Sept, Oct., Nov. Mean Temp. for (Summer) Dec., Jan., Feb. Mean Temp. for (Autumn) Mar., Apl., May. Mean Temp. for (Winter) June, July, Aug. Period of Observations North Island. Degrees. Degrees. Degrees. Degrees. Degrees. Auckland 60.3 58.8 68.6 62.3 53.3 15 years Taranaki 56.8 55.9 64.2 57.4 49.5 12 " Wellington 55.7 54.6 63.6 56.7 47.9 10 " Means for North Island 57.6 56.4 65.4 58.8 50.2 South Island Nelson 55.0 53.3 62.5 56.4 46.7 16 years Christchurch 55.1 55.5 61.4 55.9 44.5 11 " Dunedin 50.7 50.0 57.4 51.6 47.0 15 " Means for North & South Island 53.6 52.09 60.4 54.6 46.0 57.6 56.4 65.4 58.8 50.2 53.6 52.9 60.4 54.6 46.0 Means for North & South Islands 55.6 54.6 62.9 56.7 48.1

From the above Table it will be observed that in the North Island the mean annual temperature for Auckland is the highest (60.3 degs.), and that for Taranaki (56.8 degs.) the next, while Wellington is the lowest (55.7 degs.) In the South or Middle Island, Christchurch and Nelson show the highest annual mean temperature (55.1 and 55.0 degs.), and Dunedin is very much lower, viz., 50.7 degs. January and February, corresponding to July and August in England, are the two warmest months in New Zealand; and July and August, the two coldest (excepting in Nelson and Wellington, at which places the mean readings are lowest for June and July). The climate of London is 7.2 degrees colder than that of the North Island, and 3.8 degrees colder than the Middle Island of New Zealand; and the difference between the mean annual temperature of the whole of New Zealand and that of London is 5.7 degs., the former being 55.7 degs. and the latter 50 degs. The following are the means for the two warmest and two coldest months in the year in the several localities, with their differences:— Auckland. Taranaki Wellington. Nelson. Christchurch. Dunedin. 69.6 64.7 64.6 63.6 65.2 58.0 53.1 49.3 47.8 45.9 44.3 43.2 16.5 15.4 16.8 17.7 20.9 14.8 From which we find that the average difference between the mean temperature of the warmest and coldest months of the year in New Zealand is 17.0 degs.; at Rome it is 27 degs., at Montpellier 33 degs., at Milan 38 degs., and at Jersey 22 degs. The observations from these six Stations have been selected to form the above Table as they extend over a tolerably long period, and give a fair comparison of the climate of the North and South Islands. Table II.—Showing the influence of the Southern Alps on the Climate of the East and West Costs of the Middle Island; from Averages for the year 1866 and 1867. Locality Mean Annual Temperature Maximum Solar Radiation recorded. Minimum Terrestrial Radiation recorded Mean Elastic Force of Vapour. Mean Degree of Moisture. Mean Annual Rainfall. Average number of days on which Rain fell. Average Velocity of Wind, in miles per day. Degs. Degs. Degs. Inches. Sat.-100. Inches. Days. Miles. Cristchurch(East Coast.) 53.3 137.Feb. 18.July. .347 76 24.70 91 165 Hokitika (West Coast.) 52.3 103.Jan. 22.Aug. .393 89 119.00 202 133

Table III.—Showing the Rainfall in the North and Middle Islands of New Zealand, compiled from the earliest Observations to the present date, 1867. Place. Mean Annual Rainfall. Averages of Rainfall for the different Seasons of the Year, with the Mean Number of Days of Rain. Mean Number of Days on which Rain Falls Annually. Period of Observations. Spring. (Spt., Oct., Nov.) Summer (Dec., Jn., Feb.) Autumn. (Mar., April., Mary.) Winter (June, July, Aug.) North Island Inches. Inches. Days. Inches. Days. Inches. Days. Inches. Days. Days. Auckland 44.682 11.031 45 8.378 27 11.009 37 14.265 56 177 15 years. Taranaki 58.584 17.088 42 10.974 27 14.133 30 17.199 47 146 12 " Wellington 50.091 12.148 35 9.685 27 12.666 33 16.021 46 146 10 " Means for North Island 51.119 13.422 40 9.679 27 12.602 33 15.828 49 156 Middle Island. Nelson 54.721 16.746 28 13.211 17 8.795 19 14.551 23 92 16 years. Christhurch* The monthly averages for the amount of rain and the number of days of rainfall are only for eight years, while the mean annual fall and number of days are for the eleven years. 31.636 5.145 24 7.266 23 8.022 26 13.193 35 113 11 " Dunedin 32.886 8.129 44 9.428 41 7.943 38 7.253 36 178 15 " Means for Middle Island 39.747 10.006 32 9.968 27 8.253 27 11.665 31 127 51.119 13.422 40 9.679 27 12.602 33 15.828 49 156 39.747 10.006 32 9.968 27 8.253 27 11.665 31 127 Means for both Islands 45.433 11.714 36 9.823 27 10.427 30 13.746 35 141 Note.—From the above it will be observed that Taranaki has the highest average annual rainfall (58.584), and Nelson is the next (54.721), while the average means for Christchurch (31.636) and Dunedin (32.886) are the lowest; but while Dunedin has a much smaller annual fall of rain than the others, yet there are a greater number of days of rain yearly at that place than at any of the other Stations; and although the mean fall for Nelson is one of the highest averages, still the mean number of days of rain in that locality is the least of all. Taking these six Stations, the annual rainfall and number of days of rain is greater in the North than in the Middle Island.