Long-term trend of tropopause over New Delhi and Thiruvananthapuram



Radiosonde observations taken during the past 32 years at New Delhi (28°N, 77°E) and 26 years at Thiruvananthapuram (8°N, 76°E) have been analyzed to examine the long-term trend of tropopause height (TPH) and tropopause temperature (TPT) at these two stations. It appears that TPH is increasing and TPT is decreasing over the years. The trend of change is not same throughout the period of study. Considering the whole period of data we find that the increase of TPH is in the range of +0.57 to +1.13%/decade and the decrease of TPT is in the range range of −0.53 to −0.94%/decade. Qualitatively this is explainable with the decreasing trend of ozone in the stratosphere.