Estimate of the Global Change in Tropospheric Temperature Between 1958 and 1973

The tropospheric temperature change during the period 1958–1973 has been estimated from the change in thickness between 700 and 300 mb at radiosonde stations fairly evenly distributed about the world. As anticipated, the relatively large (about 0.5°C) decrease in Northern Hemisphere tropospheric temperature found by Starr and Oort between 1958 and 1963 did not persist, and between 1963 and 1973 the estimated 0.2°C temperature decrease in the Northern Hemisphere was compensated by a similar increase in the Southern Hemisphere, implying little change in global temperature. Examined is the seasonal and longitudinal variation in tropospheric temperature change as well as the temperature change in 700–500 and 500–300 mb layers. A nearly 3-year periodicity in tropospheric temperature is apparent in most regions of the world after 1963, and, particularly in the Southern Hemisphere, the rather pronounced minimum in 1963–65 associated with this periodicity could be partly due to the eruption of Mt. Agung in the spring of 1963.