The temperature records that have been kept have been intermittent readings mainly with a calibrated series of minimum and maximum-minimum thermometers. Monthly air (i.e., 3 ½ ft above the ground) maxima and minima were recorded for a full year for two stations near the Trig on Maungatua, both on open spurs at 2,400ft—one on the main seaward face (S.E.), and the other on the main inland face (N.W.), and about 1½ miles further from the sea. These did not differ consistently and never by more than 3° F. The extremes were 84° F. (Feb.) and 22° F. (Sept.). Records kept on Maungatua from March to June at four stations along a grassy ridge leading up the seaward face to the summit showed a steady fall of the monthly maximum with altitude with a range in June of 15° F. between 600ft and the Trig. In general, the monthly air minimum at the summit was about 6° F. lower than at 600ft. These records seem sufficient to establish that temperature climates are differentiated by altitude in a normal way and that there is not an east-west gradation sufficient to increase materially the temperature range of the climate of inland faces. The flat treeless summit of Maungatua does, however, experience severe ground frosts. A minimum thermometer on the ground at 2,900ft recorded in May 8° F., in June 3° F., and in July 12° F.

Several tests were made for the presence of frost pockets and inversion patterns. A series of clear grassy sites were selected for minimum thermometers at different altitudes on Mt. Cargill, Mt. Misery and Maungatua. In all cases during frosty nights an inversion pattern developed. The point of reversal on Mt. Cargill was normally below 550ft, but on Maungatua it was usually between 600ft and 1,100ft. The most intense inversion detected was in open tussock country near Bendoran during August. Misery Creek and Orbell Creek are narrow valleys separated by the spur on which Bendoran is situated.

It is clear that in this tussock country inversion patterns are pronounced, and the flats in the narrow valley bottoms experience severe frosts.

In forest country that has been partly cleared at Lee Creek, Mill Creek and Mt. Cargill the inversion patterns that developed on deforested sites were less striking while thermometers set up inside the forest showed them weakly or not at all. It was always warmer within the forest than at adjacent stations in the open, and differences between air and ground minima were usually less than 1° F. The lowest ground temperature registered in a forest clearing was 22° (Mill Creek valley bottom alt. 200ft). In the adjacent beech forest both air and ground minima were 28°, and this was the lowest reading obtained in forest.