Purushotham Pooja, Sanjay Kumar Mehta, Sachin Philip Kakkanattu, K. B. Betsy, C. J. Seetha, P. P. Musaid
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引用次数: 0
Abstract
Knowledge of the tracer characteristics, such as water vapor and ozone in the tropical tropopause layer (TTL), is vital in quantifying the radiation budget and critical to understanding the exchange processes between the troposphere and stratosphere. In this study, we have characterized the tropical tropopause parameters such as the cold point tropopause (CPT) height (CPT-H) and temperature (CPT-T), convective tropopause (COT) height (COT-H) and temperature (COT-T), and the tropical tropopause layer (TTL) using radiosonde observations during 2014–2019 over Chennai (13.0° N, 80.06° E) located in the northeast (NE) monsoon region. The water vapor and ozone data from the microwave limb sounder (MLS) simultaneous to the radiosonde observations are also utilized to understand their roles on the CPT variations for different convective conditions obtained from Infrared brightness temperature (IRBT) data. CPT over Chennai becomes higher (17.6 ± 0.3 km) and colder (189.7 ± 0.9 K) during the winter season and lower (16.6 ± 0.2 km) and warmer (192.1 ± 1.0 K) during the summer monsoon season, however, not in the same month. The water vapor (CPT-W) and ozone (CPT-O) mixing ratios at CPT are found to be lower (~ 70 ± 1.4 ppmv and 3.1 ± 0.4 ppmv) during the winter season and higher (153 ± 4.2 ppbv and 4.8 ± 0.6 ppmv) during summer monsoon season. COT, however, becomes lower (12.4 ± 0.3 km) and higher (13.3 ± 0.3 km) during pre-monsoon and summer monsoon seasons, respectively. The TTL thickness is lesser (3.5 ± 0.6 km) during the winter and greater (4.8 ± 0.8 km) during the summer monsoon seasons. Over Chennai, the seasonal variation of the upper troposphere and lower stratospheric temperature, water vapor, and ozone anomalies are in phase. We have categorized tropical convections as non-penetrative and penetrative using IRBT data. It is observed that the TTL temperature warms with the increasing strength of the non-penetrative convections and cools for the penetrative convection.
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pure and applied geophysics (pageoph), a continuation of the journal "Geofisica pura e applicata", publishes original scientific contributions in the fields of solid Earth, atmospheric and oceanic sciences. Regular and special issues feature thought-provoking reports on active areas of current research and state-of-the-art surveys.
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Publishes peer-reviewed original scientific contributions and state-of-the-art surveys in solid earth and atmospheric sciences
Features thought-provoking reports on active areas of current research and is a major source for publications on tsunami research
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