UTLS Science:

UTLS - Science - START-08 Campaign

START-08

(Stratosphere-Troposphere Analyses of Regional Transport)

Spring 2008

Principal Investigators

Elliot Atlas
305.421.4128
Univ. of Miami
4600 Rickenbacker Causeway, Miami, FL 33149

Ken Bowman
979.862.4060
Texas A&M
3150 TAMU, College Station, TX 77843-3150

Laura Pan
303.497.1467
NCAR-TIIMES-ACD
P.O. Box 3000, FL0-2160, Boulder, CO 80307

Co-Investigators

Teresa Campos
NCAR

Brian Ridley
NCAR

Sue Schauffler
NCAR

Britton Stephens
NCAR

Simone Tilmes
NCAR

NCAR

START08 & preHIPPO Field Campaign Workshop

8 - 9 January 2008

NCAR: Boulder, Colorado

Stratosphere-Troposphere Analyses of Regional Transport (START-08) and HIAPER Pole-to-Pole Observations (HIPPO) of Carbon Cycle and Greenhouse Gases experiment will have a joint payload and operation in Spring 2008. During this workshop, the investigators will provide an overview of the scientific issues the experiments planned to address. Related modeling and satellite data analyses will be discussed. Planning for forecast and flight operations will also be part of the workshop. We invite the community’s participation and scientific involvement in the project.

To Join the START-08 email group:

START-08 email group

To join the email group, send an e-mail to

start_all-subscribe@mailman.acd.ucar.edu

(note the underscore in start_all)

Figure 1 . This schematic highlights the important processes coupling dynamics, chemistry, and cloud microphysics in the UTLS region. The green line denotes the time average tropopause. The gray line illustrates synoptic scale processes that contribute to stratosphere-troposphere two-way exchange, such as frontal lifting, tropopause folds, and intrusions. In addition, convection brings near-surface pollutants into the upper troposphere, strongly influencing global-scale chemistry. Major transport pathways are indicated by bold arrows. The yellow arrow indicates the dynamical coupling of the tropical UT and extratropical LS by large-scale wave activities. The blue arrow shows the stratospheric intrusions into troposphere near the jet streams. The red arrow represents the upward transport by frontal lifting along the warm conveyor belts. The white cloud represents the convective transport. In addition, large scale stratospheric circulation contributes to the downward transport.

Mission Outline

We propose a field experiment, Stratosphere- Troposphere Analyses of Regional Transport (START-08), for the Spring 2008 time period, to study the transport characteristics of the ExUTLS region. START08 will take advantage of the capabilities of HIAPER (ideal altitude and range for sampling the ExUTLS, as demonstrated in Figure 1) and set the stage for more complex and comprehensive field studies of UTLS chemistry and microphysics currently in the planning stages.

Figure 2. Ozonesonde climatology for May based on Fortuin and Kelder [1998]. White contours are zonal wind from NCEP indicting the position of the subtropical jet. This figure, complementing Figure 4, shows that the ozone distribution in UTLS is significantly influenced by the major transport pathways.

The science focus will be on the characterization of the structure and major transport processes of the extratropical UTLS and on chemical distributions and relationships in that region. In situ measurements of meteorological parameters, trace species, and microphysical properties will be used in combination with model simulations of regional dynamics to trace the history of the air found in this region and to better understand the transport boundary between the UT and LS. Since transport processes dominate the chemical distributions and microphysical conditions in the UTLS, START08 will improve understanding chemistry and microphysics in this region by developing effective observational and modeling tools for characterizing major transport influences.