Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 5.509 IF 5.509
  • IF 5-year value: 5.689 IF 5-year 5.689
  • CiteScore value: 5.44 CiteScore 5.44
  • SNIP value: 1.519 SNIP 1.519
  • SJR value: 3.032 SJR 3.032
  • IPP value: 5.37 IPP 5.37
  • h5-index value: 86 h5-index 86
  • Scimago H index value: 161 Scimago H index 161
Discussion papers
https://doi.org/10.5194/acp-2018-724
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-2018-724
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 30 Jul 2018

Research article | 30 Jul 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).

Lagrangian simulations of the transport of young air masses to the top of the Asian monsoon anticyclone and into the tropical pipe

Bärbel Vogel1, Rolf Müller1, Gebhard Günther1, Reinhold Spang1, Sreeharsha Hanumanthu1, Dan Li1,2, Martin Riese1, and Gabriele P. Stiller3 Bärbel Vogel et al.
  • 1Forschungszentrum Jülich, Institute of Energy and Climate Research – Stratosphere (IEK-7), Jülich, Germany
  • 2Key Laboratory of Middle Atmosphere and Global Environment Observation (LAGEO), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
  • 3Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany

Abstract. We have performed backward trajectory calculations and simulations with the 3-dimensional Chemical Lagrangian Model of the Stratosphere (CLaMS) for two succeeding monsoon seasons using artificial tracers of air mass origin. With these tracers we trace back the origin of young air masses (age<6 months) at the top of the Asian monsoon anticyclone and of air masses within the tropical pipe (6 months<age<18 months) during summer 2008. The occurrence of young air masses (<6 months) at the top of the Asian monsoon anticyclone up to ≈460K is in agreement with satellite measurements of chlorodifluoromethane (HCFC-22) by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument. HCFC-22 can be considered as a regional tracer for continental eastern Asia and the Near East as it is mainly emitted in this region.

Our findings show that the transport pathway of air masses from boundary sources in the region of the Asian monsoon into the tropical pipe occurs in three distinct steps. First, very fast uplift in a convective range transports air masses up to 360K potential temperature within a few days. Second, air masses are uplifted from about 360K up to 460K within an upward spiralling range within a few months. The large-scale upward spiral extends from northern Africa to the western Pacific. The air masses are transported upwards by diabatic heating with a rate of up to 1–1.5K per day, implying strong vertical transport above the Asian monsoon anticyclone. Third, transport of air masses occurs within the tropical pipe up to 550K associated with the large-scale Brewer–Dobson circulation within ~one year.

In the upward spiralling range, air masses are uplifted by diabatic heating across the (lapse rate) tropopause, which does not act as a transport barrier under these conditions. Further, in the upward spiralling range air masses from inside the Asian monsoon anticyclone are mixed with air masses convectively uplifted outside the core of the Asian monsoon anticyclone in the tropical adjacent regions. However, this upward transport is weak in terms of transported air masses compared to the quasi-horizontal transport from the monsoon anticyclone into the northern lower stratosphere and tropical tropopause region. Air masses from the Asian monsoon anticyclone (India/China) contribute a minor fraction to the composition of air within the tropical pipe at 550K (6%), the major fractions are from Southeast Asia (16%) and the tropical Pacific (15%).

Bärbel Vogel et al.
Bärbel Vogel et al.
Bärbel Vogel et al.
Viewed
Total article views: 310 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
235 66 9 310 10 9
  • HTML: 235
  • PDF: 66
  • XML: 9
  • Total: 310
  • BibTeX: 10
  • EndNote: 9
Views and downloads (calculated since 30 Jul 2018)
Cumulative views and downloads (calculated since 30 Jul 2018)
Viewed (geographical distribution)
Total article views: 310 (including HTML, PDF, and XML) Thereof 308 with geography defined and 2 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited
Saved
No saved metrics found.
Discussed
No discussed metrics found.
Latest update: 15 Nov 2018
Publications Copernicus
Download
Short summary
We are interested to study the transport pathway of air masses from the region of the Asian monsoon into the stratosphere because this region is very sensitive for climate change. Our findings show that this transport occurs in three distinct steps.
We are interested to study the transport pathway of air masses from the region of the Asian...
Citation
Share