A CE Suborbital Science Activities

1. Jay Mace (Clouds), Jens Redemann (Aerosols), Norm Nelson (Ocean Eco.) And many helpful people too numerous to list here ACE Suborbital Science Activities • Contents: • Role of the suborbital program • Pre- and post-launch objectives for each discipline • Timing of suborbital activities • Ideas for specific field experiments • Most pressing needs for aerosol sub-discipline • Mission statement: “The ACE Suborbital Activities (ASA) will support the testing of design concepts and related retrieval algorithms for the ACE orbital instruments in the ACE pre-launch phase, and will augment the ACE suite of aerosol, cloud and ocean observations through on-going suborbital measurements in the post-launch phase as necessitated by the overall ACE mission science requirements.”

2. ACE suborbital activities: objectives

3. Cal/val concept matrix: Aerosols - 1 - All capabilities need to be tested for different aerosol types, clear-sky & partly cloudy, different surfaces types, measurement geometries, Day-time vs. night-time requirements, etc.

4. Cal/val concept matrix: Aerosols - 2 -

5. Ideas for specific field experiments: example 1

6. Ideas for specific field experiments: example 2 Aerosol properties and DARF in the vicinity of clouds with ACE Topic 1: semi-direct and indirect effects Topic 2: cloud fraction and impact on DARF Aerosol properties as f(x)

7. ACE Major Suborbital Field Campaignsver. 03/09 • MACPEX • Mid-latitude Airborne Cirrus Properties Experiment • WB-57, Houston, TX • Need to add remote sensing • ACE-PODEX10 • Polarimeter Definition Experiment • High priority design/algorithm issues • ER-2 + P-3B, Wallops or Dryden • PAC3E - Pacific Atmospheric Composition, Cloud, and Climate Experiment • Instrument design/combination/algorithm issues specific to ACE science questions • DC-8, ER-2, SE Asia • ACE-PEX12 (ACE Precursor-Experiment) • Study aerosol properties near clouds and DARF as function of distance from clouds • ER-2, P-3B, + in-situ a/c Wallops? • ACE - ALDEX • Algorithm Development Experiment to support multi-sensor algorithm development • ER-2 + P-3B, Wallops or Dryden • ACE-VEX17-19 (Validation Experiment) • ACE product and algorithm validation • ACE-SVEX17-19 (Science and Validation Exp.) • ACE product and algorithm validation • Suborbital measurements as necessitated by ACE science questions/requirements Science focus: Ocean Ecosystems Aerosols Clouds

8. Most pressing needs for aerosol sub-discipline • A data set to define the polarimeter characteristics • Suborbital measurements not demonstrated to be up to task: Measurements of spectral aerosol absorption and phase function need to be a priority for a designated mission. * Fly separate airborne platforms, one with the simulator(s), another platform with suitable radiation and in situ capabilities; the latter needs to fly both in stacked formation and spiral vertically below the simulator platform # Clear-sky & partly cloudy, different surfaces

9. Ideas for specific field experiments: example 3 Aerosol absorption and phase function validation for AERONET Absorption Aerosol Optical Depth In situ vs. Radiometric methods vs. sky radiance inversion

10. Summary • The ACE suborbital science activities are integral parts of the ACE science objectives as well as cal/val in all three of the ACE sub-disciplines. • Prelaunch activities will include: • instrument development, such as the airborne simulators for the ACE instruments, as well as instrument suitable for the testing of the simulators • algorithm development • Cal/val for testing of the suborbital simulators • Post-launch activities will include: • Cal/val for orbital instruments • Continued algorithm development • sustained operation of suborbital platforms and sensors as defined by the overall mission science requirements • Need interdisciplinary experiment(s) with coherent science objectives that can also serve cal/val needs in the post-launch timeframe. • Very strong need for investment in instrument simulators in the very near term - i.e. with this year's stimulus money, if possible. • We should be thinking of innovative strategies to use existing technologies, infrastructure and data sets (e.g., data sets from previous missions). • Urgent need for polarimeter definition experiment and campaign to compare different methods for measuring spectral absorption and phase functions (Aeronet vs. radiometric vs. in situ).