Journal Article

FZJ-2020-05409

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Cirrus cloud shape detection by tomographic extinction retrievals from infrared limb emission sounder measurements

Ungermann, J. (Corresponding author)FZJ* ; Bartolome, I.FZJ* ; Griessbach, S.FZJ* ; Spang, R.FZJ* ; Rolf, C.FZJ* ; Krämer, M.FZJ* ; Höpfner, M. ; Riese, M.FZJ*

2020
Copernicus Katlenburg-Lindau

This record in other databases:    

Please use a persistent id in citations: http://hdl.handle.net/2128/26645  doi:10.5194/amt-13-7025-2020

Abstract: We investigate the impact of model trace gas transport schemes on the representation of transport processes in the upper troposphere and lower stratosphere. Towards this end, the Chemical Lagrangian Model of the Stratosphere (CLaMS) was coupled to the ECHAM/MESSy Atmospheric Chemistry (EMAC) model and results from the two transport schemes (Lagrangian critical Lyapunov scheme and flux-form semi-Lagrangian, respectively) were compared. Advection in CLaMS was driven by the EMAC simulation winds, and thereby the only differences in transport between the two sets of results were caused by differences in the transport schemes. To analyze the timescales of large-scale transport, multiple tropical-surface-emitted tracer pulses were performed to calculate age of air spectra, while smaller-scale transport was analyzed via idealized, radioactively decaying tracers emitted in smaller regions (nine grid cells) within the stratosphere. The results show that stratospheric transport barriers are significantly stronger for Lagrangian EMAC-CLaMS transport due to reduced numerical diffusion. In particular, stronger tracer gradients emerge around the polar vortex, at the subtropical jets, and at the edge of the tropical pipe. Inside the polar vortex, the more diffusive EMAC flux-form semi-Lagrangian transport scheme results in a substantially higher amount of air with ages from 0 to 2 years (up to a factor of 5 higher). In the lowermost stratosphere, mean age of air is much smaller in EMAC, owing to stronger diffusive cross-tropopause transport. Conversely, EMAC-CLaMS shows a summertime lowermost stratosphere age inversion – a layer of older air residing below younger air (an “eave”). This pattern is caused by strong poleward transport above the subtropical jet and is entirely blurred by diffusive cross-tropopause transport in EMAC. Potential consequences from the choice of the transport scheme on chemistry–climate and geoengineering simulations are discussed.

---

Contributing Institute(s):

1. Stratosphäre (IEK-7)
2. Jülich Supercomputing Center (JSC)
3. JARA - HPC (JARA-HPC)

Research Program(s):

1. 244 - Composition and dynamics of the upper troposphere and middle atmosphere (POF3-244) (POF3-244)
2. 511 - Computational Science and Mathematical Methods (POF3-511) (POF3-511)
3. Tomographic retrievals of temperature and trace gasses from GLORIA measurements (jiek72_20200501) (jiek72_20200501)

Appears in the scientific report 2020

---

Database coverage:
; ; ; ; Article Processing Charges ; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; DOAJ Seal ; Ebsco Academic Search ; Essential Science Indicators ; Fees ; IF < 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

---