Trajectory analysis on the Asian Tropopause Aerosol Layer (ATAL) based on balloon measurements at the foothills of the Himalayas / Sreeharsha Hanumanthu. Wuppertal, August 19, 2021
Inhalt
- Abstract
- Motivation
- Introduction
- Meteorological background
- Upper troposphere, lower stratosphere and tropopause
- Tropical tropopause layer
- Inter tropical convergence zone
- Tropical cyclones
- The monsoon systems
- Features of the South Asian summer monsoon
- Onset and withdrawal
- Subtropical Jetstream
- Monsoon precipitation
- El Niño southern oscillation influence on Asian monsoon circulation
- Rossby wave wave breaking and eastward eddy shedding
- Asian summer monsoon anticyclone
- Asian tropopause aerosol layer
- Measurements of the Asian Tropopause aerosol layer
- Chemical composition of Asian tropopause aerosol layer particles
- Asian tropopause aerosol layer and cirrus coexistence
- Overview of this thesis
- Instrumentation and the balloon campaigns in India and Nepal
- Overview of the balloon measurements in northern India 2016 and Nepal 2017
- Balloon-borne campaign in Naintal, India 2016
- The balloon payload
- Vaisala RS41-SPG radiosonde
- Electrochemical concentration cell
- Cryogenic frostpoint hygrometer
- Compact optical back-scatter aerosol detector
- Detection of the aerosol in the observed shortwave and long-wave channel
- First results of measured ozone and water vapor in Nainital 2016
- Results of COBALD Measurements
- Color index and ice saturation
- Data analysis and processing
- Aerosol back-scatter measurements in August 2016
- Model description and meteorological conditions
- The chemical Lagrangian model of the stratosphere
- Trajectory calculations
- Meteorological conditions of the Asian monsoon 2016
- Model Results
- Day-to-day variability of the Asian tropopause aerosol layer
- Trajectory calculation and classification
- Source regions of air masses contributing to the Asian tropopause aerosol layer
- Sensitivity of strong-updraft location
- Diversity in boundary layer sources
- Sensitivity on backward trajectory length
- Results of the back-trajectory analysis: Three cases
- Case 1: Established Asian tropopause Aersol layer on 6 August 2016
- Case 2: No Asian tropopause aerosol layer on 15 August 2016
- Case 3: Typhoon influence on 18 August 2016
- Results for all flights
- Discussion and summary
- Appendix
- Measured raw signal of balloon soundings
- Sensitivity of 40 day run in different time-lengths
- 40, 60 and 80 day trajectory variability in source regions
- List of Abbreviations
- Acknowledgements
- Bibliography