Deep Convective Clouds and Chemistry (DC3) Field Experiment

Principal Investigators:

Mary Barth (NCAR), Bill Brune (PSU), Chris Cantrell(NCAR), Steve Rutledge (CSU)

Steering Committee:Ken Pickering Jim Crawford Laura Pan Andrew Heymsfield Don Lenschow Owen Cooper Andy Weinheimer Paul Krehbiel Jeff StithAlan Fried

DC3: Characterize the effects of continental, midlatitude

deep convection on the transport and transformation of ozone and its precursors

http://utls.tiimes.ucar.edu/Science/dc3.shmtl

1. Processing in the convection,

2. Processing in the anvil

3. Processing in the convective outflow 12-48 hours later

4. Contrast different types of convection and different emission regions

Ancillary Objectives of DC3

1. Halogen Chemistry in the UTLS

2. Determine mass fluxes of air and trace gases into and out of the storm,

3. Cloud electrification and lightning discharge processes

4. Effects of deep convection on UT water vapor

5. Convective processing of aerosols and their impact on water and ice particles

http://utls.tiimes.ucar.edu/Science/dc3.shmtl

A Storm Penetrating Aircraft (SPA) can help reach these objectives:

1. Processing of trace gases in the convection,

2. Processing in the anvil (mid to lower regions)

3. Cloud electrification and lightning discharge processes

4. Effects of deep convection on UT water vapor

5. Convective processing of aerosols and their impact on water and ice particles

Importance of Production of NOx by Lightning

Barth et al., 2006, submitted to JGR

Cross Section of CO

ppbv

CO used as a tracer of boundary layer air

Barth et al., 2006, submitted to JGR

Soluble Species and Their Fate in Deep Convection

Total CH2O mixing ratios = gas + cloud water + rain + ice + snow + hail

Barth et al., 2006, submitted to JGR

Transects across Anvil

Disagreement among models, but no observations available

CH2O (gas)

H2O2 (gas)

HNO3 (gas)

CO

CO

O3

O3

Barth et al., 2007, in preparation

Priority Instruments on a SPA to Understand Convective Processing of Constituents

1. NO

150 lbs., 10 pptv detection limit, and 0.5-sec time response

(courtesy of Andy Weinheimer, NCAR)

2. CO

3. Soluble Species:

Formaldehyde, Hydrogen Peroxide, Nitric Acid