Modeling Deep Convection and Chemistry and their Roles in the
Tropical Tropopause Layer
Workshop in Victoria, BC June 2006
SPARC, GEWEX, IGAC
Barth, McFarlaneWith contributions from: Petch, Birner, Grabowski
Deep convection/Chemistry and their Roles in the Tropical Tropopause Layer
Chemistry in Tropical Tropopause Layer
• Ozone in the UTLS region – climate change
– UV radiation reaching the Earth’s surface
• Halogen chemistry
June 2006 Workshop Wish List Outcomes
Information sharing (newsletters, web page with talks and other information)
Special sessions at meetings (e.g. SPARC 2008 GA, IGAC 2008, AGU and EGU special sessions)
• Modeling activities– Re-run a previous GCSS case (e.g. TOGA-COARE) TWP-ICE intercomparison
• Establish working group composed of people from each of the communities (SPARC, GEWEX, IGAC)– Develop a framework for collaborative research and plan future
activities
TWP-ICE intercomparison (GEWEX activity primarily)
• Ann Fridlind is leading an intercomparison of CRMs, SCMs, LAMs, NWP models
• Took suggestions from 2006 workshop– Raised the model top– Included tracers
• Intercomparison is progressing nicely• No one has analyzed tracer output yet
Other Activities
• GABRIEL, HIBISCUS, TROCCINOX, SCOUT-O3, ACTIVE (Hector) storms being analyzed – recent papers
• AMMA results – recent papers
• TC4-Costa Rica
• CRM studies of role of overshooting convection in TTL dehydration (e.g. Jensen et al, 2007)
• Fueglistaler et al (2009) review paper
• Analyses of TTL features in GCM Simulations (e.g. Gettelman&Birner, 2007, Gettelman et al, 2008, Birner, 2009)
do not know of any coordinated modeling activities, but AMMA may provide the next GEWEX intercomparison
– AMMA intercomparison would likely be good in terms of having measured chemical species
T. Birner (2009) submitted
Analysis of the tropical tropopause layer using the Nonhydrostatic Icosahedoral Atmospheric Model (NICAM)
IGAC-SPARC (Kyoto Univ.) OCT. 25, 2009※Hiroyasu Kubokawa, Masatomo Fujiwara (ES, Hokkaido Univ.)
Tomoe Nasuno (RIGC, JAMSTEC)Masaki Satoh (CCSR Tokyo Univ./ RIGC,JAMSTEC)
IGAC-SPARC Workshop poster P-18
H. Kubokawa et al., JGR, in press
Follow - on from:
ＮＩＣＡＭ (Nonhydrostatic ICosahedral Atmospheric Model ) Explicit vertical wind calculation; No cumulus parameterization.Cloud microphysical scheme (Grabowski, 1998)● horizontal spacing : 3.5 km, 7 km, 14 km vertical spacing : 1.4 km in the upper troposphere.
“ Dec. 2006, MJO simulation” ・ Initial condition : NCEP Tropospheric Analyses data14 km, 7km ; 15 Dec. 2006, 0000UTC ～ 32 days (per 6 hr. snapshot)3.5 km ; 25 Dec. 2006, 0000UTC ～ 7 days (per 90 min. 90min averaged)In this presentation, 7 km grid data is only used. ・ without using the nudge technique during the integration. ・ SST (weekly mean data from Reynolds SST) ※In this presentation, we discuss the regional characteristics of deep convection, which may affect the transport into the TTL and the variations of temperature and water vapor in the TTL.
Western Pacific
tropopause
16 km
TTL bottom boundary
CPC-IR 202.48 [K]
south coast of Java, north area of Australia (tropical storm Isovel, 29 ～ Dec. 2006) Fudeyasu et al. 2009
ITCZ (westward propagating clouds with 500 km scale in horizontal)
Overshooting frequency
Future Activities
Idealized modeling case
1000s kms
100s kms
x < 5 km
• Sensitivity of TTL structure (moisture) to cloud microphysics• Evaluate single column models (SCM)• Evaluate role of convective waves on T and qv structure
Future Activities
Challenge: having observations of large-scale dynamics, cloud microphysics AND chemistry
Future Field CampaignsPACE (NASA) – possibly
sample the Asian MonsoonAre there others?
Courtesy Mijeong Park
Important to Support Tropical Studiesclimate change
• Rising of the Tropopause – documented• Tropics are/were broadening• Impacts
– Cloud formation, adsorption of HNO3, radiation– Precipitation– Regional climate– Possible coupled effects
Courtesy S. Davis via A. Gettelman, UTLS Workshop, Boulder, CO, Oct
2009
∆TPP=20 mb
Summary
• Many activities have been done during the past 3 years by each of the communities
• The GEWEX community has implemented suggestions from the 2006 workshop (higher model top, tracers in CRMs)
• Large-domain, cloud-resolving-scale simulations are beginning but at early stages - none with tracers and/or chemistry (Poster P-18)
• Suggestions of promoting an idealized case, but still no chemistry
• Would an AMMA case meet needs of large-scale dynamics, cloud physics and chemistry?
• Another TTL-UTLS workshop would bring people together again – maybe this time effort should be placed on beginning such a case study
