1. Overview of SAC Activities  Thank you to the hard work of the ATD staff and the outside community.  Received large amounts of information and we are still digesting this input. There will be errors and omissions, but this effort is ongoing.  Encouraged by the increased level of communication between divisional scientists.  Apologize in advance for a relatively dry presentation. It does not focus on science or engineering, but on planning.

2. SAC Process to Date  Input from RTF science group and instrument leads began in late November 2003.  SAC met in January and defined six research themes  Leads named in six scientific areas, input collected from the division, NCAR, and the broader community  SAC retreat took place on 23 January 2004 Additional research themes discussed Additional research themes discussed Cross-cutting measurement needs identified Cross-cutting measurement needs identified  Since the retreat, input has been received on research themes, measurement needs, role of ATD in meeting these measurement needs, impacts on division, and role of strategic partnerships  Discussion today begins with the original research themes (Biogeo Sciences, Chemistry, Climate, Geophysical Turbulence, Weather, Water Cycle) – we attempted to fit the other areas identified into these themes

3. 1 - What are the local, regional, and continental-scale exchanges of carbon, nitrogen, and reactive species? What are their relationships to underlying ecosystem parameters and processes? How are they responding to environmental, climatic, atmospheric-chemistry, and land-use perturbations? 2 - How can we measure terrestrial exchange of CO 2 and other greenhouse gases on the time and space scales required to support domestic carbon management efforts and international climate treaties? 3 - How do coupling between carbon, nitrogen, iron, and sulfur cycling and associated non-linear feedbacks affect climate, air quality, and ecosystem function on local to global scales? 4 – What is the influence of mineral aerosols on other biogeochemical cycles? How are they transported from the continents and how are these processes changing? Biogeosciences -- priority scientific topics Lead: Britt Stephens

4. Biogeosciences -- observations Airborne: Instrumentation for fast-response, precise, and accurate measurements of CO 2, CO, H 2 O, O 3, O 2 /N 2, CO 2 isotopes, radon, and photochemically active species. A flask system or systems for collection of discrete, dried, unfractionated samples for laboratory analyses of these and other gases or isotopes. Instrumentation for eddy flux measurements of CO 2, CO, O 3, and H 2 O. Disjunct eddy accumulator to enable flux measurements of a wide range of compounds. Remote sensing instrumentation, including hyperspectral imaging, CO 2 LIDAR, microwave soil moisture, and accurate surface IR temperature imaging. Ground based: Tower based eddy flux measurements for CO 2, H 2 O, and energy. Medium arrays of towers (10-20) and instruments for concentration of CO 2 and other species. Large (100-1000) arrays of intelligent sensors for high variability environmental parameters. Advanced tethered balloon instrumentation for multi-species boundary layer profiles. Enclosure techniques for measuring soil and plant exchange of CO 2 and reactive species.

5. Strategic Partnerships: Many BGS measurements require a high level of specific expertise. New mechanisms may be necessary to allow for and encourage support of community instrumentation by non-ATD scientists and technicians. Examples could include instrumentation for reactive nitrogen species supported by ACD and HIAPER MREFC developments supported by a university. Long-term monitoring: Many BGS questions can only be addressed by measurements in all seasons or for multiple years. This will require relatively autonomous instrumentation and a capacity to support regular annual cycle length campaigns. In the case of longer deployments, technology transfer from ATD to universities may be the preferred means of support. Advanced calibration: Many BGS measurements require high levels of precision and accuracy that can only be achieved through rigorous calibration procedures, including for example the maintenance and propagation of calibration scales based on suites of high-pressure gas cylinders. Training: The BGS community has relatively less experience utilizing ATD facilities and less infrastructure for advanced instrument development and airborne science. NCAR should partner with universities and agencies to entrain BGS students and postdocs into earth system observing technique development, and provide internship and summer opportunities and curricular material. Biogeosciences – ATD role and impact

6. 1.UT/LS HO x Radical, Radical Precursors, and Ozone Chemistry: - Numerous questions related to Ozone and radical production/destruction - Unknown sources of stratospheric water 2.Highly Reactive VOCs Over Forest Canopies (large global effects): - Unknown sources of reactive VOCs - Unknown reactions that produce and destroy ozone and hydrogen radicals - Unknown nighttime reactions 3.Marine Boundary Layer Chemistry & Fluxes: - Sparse database on marine fluxes, fluxes for most trace gases & global influence - Poor understanding of halogen-aerosol chemistry 4. Aerosol Chemistry - Cloud-active aerosol particles (CCN, IN, Giant Nuclei) - Identification & Characterization of Aerosols - Radiative Properties 5. Emission of Pollution, Air Quality & Health Effects - lack of gas & aerosol data near cities - Poor understanding of transport and chemical transformations - Poor understanding of health effects - identifying terrorist events around major metropolitan centers Priority Scientific Topics: Chemistry Alan Fried -- lead

7. 1.UT/LS HO x Radical Chemistry on HIAPER: - Formaldehyde, methanol, CO, H 2 O, O 3, H 2 O/HDO, in situ aerosol sampler 2. Highly Reactive VOCs Over Forest Canopies - Formaldehyde, methanol, CO, H 2 O, O 3, CO 2 isotopes 3. Marine Boundary Layer Chemistry & Fluxes - Formaldehyde, methanol, CO, H 2 O, O 3, CO 2 Isotopes, in situ & remote Doppler LIDAR aerosol measurements, PH 4. Chemistry on Aerosols: - CCN, IN, CN, HTDMA, vertical velocities 5. Emission of Pollution, Air Quality & Health Effects - Formaldehyde, methanol, CO, H2O, O3, CO2, isotopes Observational Needs

8. Role of ATD 1. UT/LS HOx Radical Chemistry on HIAPER: - Develop next generation HIAPER instruments for formaldehyde, methanol, CO, H2O, O3, H2O/HDO, in situ aerosol samplers - Partnership in setting up inlet testing and validation facility - Lead effort to develop open path instruments on HIAPER 2. Highly Reactive VOCs Over Forest Canopies - Potentially lead such studies 3. Marine Boundary Layer Chemistry & Fluxes: -Partnership in such studies (in situ & remote, Doppler LIDAR, aerosol measurements, PH) 4. Chemistry on Aerosols: - Develop instruments to measure CCN, IN, CN, HTDMA - Lead effort to develop a network of CCN counters -Lead effort to develop compact eye-safe Doppler LIDAR 5. Emission of Pollution, Air Quality & Health Effects - Participate in field studies (MIRAGE) - Deploy aerosol LIDAR for plume mapping and flight plan guidance - Deploy eye-safe LIDAR in major metropolitan centers to identify bio-agent release and dispersion

9. Climate -- Priority Scientific Topics June Wang -- lead 1. High-quality, long-term climate monitoring: “To create a permanent climate observing system.” (BASC, 1998) 2.Upper Troposphere and Lower Stratosphere (UT/LS): To quantify the influences of ozone, water vapor, cirrus clouds, aerosols and inter- related processes in UT/LS on climate change, To reconcile observations of global warming (surface versus atmos. obs), To assess and understand long-term changes of UT/LS humidity, 3. Clouds/Aerosols: To improve the climatological knowledge of aerosols and their sources, development, transport mechanisms and sinks, To study cloud-aerosol interactions, including the feedback of clouds on climate change, To provide the measurement basis for developing cloud and aerosol parameterization schemes aimed at improving the physics in climate and other large-scale models.

10. Observational Needs 1.High-quality, long-term climate monitoring: Regular and sustained measurements of water vapor, temperature, winds, clouds, ozone, aerosol, green-house gases with strong interest in upper- troposphere and lower stratosphere (UT-LS) Components of radiation budget 2. Upper Troposphere and Lower Stratosphere (UT/LS): Reference soundings providing UT/LS temperature and water vapor measurements, Airborne in-situ sensors and remote sensing on HIAPER for process studies and satellite validations (i.e., water vapor DIAL, TDL, in-situ cloud/aerosol sensors, hyperspectral remote sensing, and aerosol lidar).

11. 3.Clouds/Aerosols: Airborne in-situ and remote sensing of cloud and aerosol properties on NCAR aircraft, multi-spectral remote sensing for cloud microphysical properties Standard airborne and ground-based aerosol package aimed at sizing aerosols over the entire size spectrum for inter-comparisons in different regions over a number of years, 4. Also interaction of atmosphere with surface properties, but dealt with in other areas Observational Needs (continued)

12. ATD Role To develop reference radiosonde for UT/LS/monitoring and explore partnerships with NOAA, NASA, WMO and manufacturers To develop and operate selected instruments on a regular and sustained base at test sites (such as Marshall) to collect research-quality and long-term climate data (requires new mission and partners) To establish a “sensor calibration and validation” facility to assist the transition and new developments of operational climate observing systems. Work with HIAPER process, UT/LS initiative, NSF, NASA and others to ensure needed remote sensing measurements for climate are on the aircraft (aerosol, cloud, precipitation, water vapor, hyper or multi-spectral sensing) To create a standard airborne and ground-based aerosol package aimed at sizing aerosols over the entire size spectrum for inter-comparisons in different regions over a number of years, role of in-situ obs as reference for lidar

13. ATD Role (cont)  Continue and expand in-situ measurements of aerosol, cloud and precipitation particles with a goal to be the world’s resource for integrated in-situ measurements of aerosol, cloud, precipitation particles.  Partner and collaborate Instrument design and calibration: ACD, NOAA, CU, CSU, CalTech, DLR Instrument design and calibration: ACD, NOAA, CU, CSU, CalTech, DLR Aircraft air sample inlets: ACD, DU, DOE, EUFAR (European Fleet for Airborne Research) Aircraft air sample inlets: ACD, DU, DOE, EUFAR (European Fleet for Airborne Research) Cloud probes: UWyo, EUFAR To create a standard airborne and ground-based aerosol package aimed at sizing aerosols over the entire size spectrum for inter- comparisons in different regions over a number of years Cloud probes: UWyo, EUFAR To create a standard airborne and ground-based aerosol package aimed at sizing aerosols over the entire size spectrum for inter- comparisons in different regions over a number of years Partner to develop UAV as a platform for cloud and aerosol observations? Partner to develop UAV as a platform for cloud and aerosol observations? U Hohenheim, NASA, Wisconsin, DLR, NOAA et al. for lidar U Hohenheim, NASA, Wisconsin, DLR, NOAA et al. for lidar

14. Geophysical Turbulence Priority Scientific Topics: Don Lenschow -- lead  Investigate complex flow regimes over heterogeneous terrain over heterogeneous terrain stable PBLs stable PBLs free-tropospheric turbulent layers free-tropospheric turbulent layers wall flow regimes wall flow regimes wave-atmosphere interactions over the ocean wave-atmosphere interactions over the ocean  Study structures in turbulent flows vortices vortices microfronts microfronts rolls and cells rolls and cells  Air motion measurements−both direct and remote−from fast-moving platforms fast-moving platforms surface-based platforms surface-based platforms  Improve sub-filter scale parameterizations in LES models

15. Observational Needs  Better spatial and temporal resolution for both in situ and remote measurements, including both scalars and velocity components via large instrument arrays, lidar and radar, and better integration of measurements from instrument arrays (e.g. Intelligent Sensor Array)  More accurate measurements of flow structures from smallest scales (e.g. intermittency at a few cms) to largest scales (e.g. pockets of cells, lines of rolls, and mesoscale convection of 10’s of kms)  3D mean and turbulence wind and scalar (T, H 2 O, O 3, CO, DMS, SO 2, aerosols, etc.) fields in both cloudy and clear air  Fluid modeling capability for obtaining flow around platforms in support of air motion measurements, sampling inlets, and particle sampling  New platforms Umanned Aerial Vehicles (UAV) Umanned Aerial Vehicles (UAV) TRAnsect Measurements (TRAM) TRAnsect Measurements (TRAM) balloon and kite-borne sensor packages balloon and kite-borne sensor packages

16. What will be required to accomplish these efforts?  strategic partnerships remote sensing - NOAA/ETL, Hohenheim Univ., DLR, Lund Univ., Univ. of Wyoming remote sensing - NOAA/ETL, Hohenheim Univ., DLR, Lund Univ., Univ. of Wyoming balloon and kite platforms - CIRES, RAP balloon and kite platforms - CIRES, RAP  improved quality control calibration capabilities - flow modeling, direct and remote sensing comparisons, calibration capabilities - flow modeling, direct and remote sensing comparisons,  adapting measurement techniques to different platforms compressibility effects on aircraft compressibility effects on aircraft flow distortion on fixed and mobile platforms flow distortion on fixed and mobile platforms measuring platform motions on mobile platforms (e.g. aircraft, ships, tethered systems, TRAM) measuring platform motions on mobile platforms (e.g. aircraft, ships, tethered systems, TRAM)

17. Water Cycle Research Topics Dave Parsons -- lead  Water vapor, which is a key aspect of the water cycle is not measured accurately enough for research needs  Research leading to improved model response to surface properties  Research leading to improved model treatment of precipitation (CCN to cloud to rainfall to runoff)  Regional water cycle experiments to examine feedbacks between the different components of the water cycle

18. Observing Needs  General effort to better measure water vapor and water vapor fluxes  Surface in-situ measurements: Fluxes and means, vegetation (NDVI, LAI, PAR, stomal conductance, etc.), soil measurements (soil composition, conductivity, shallow and deep soil moisture)  In-situ measurement of aerosol particles (CCN to ultra-giant nuclei; ice nuclei), their impact on precipitation development and subsequent impact of cloud particle size distributions on precipitation efficiency.  Water cycle airborne remote sensing: aerosol, surface properties, cloud and precipitation, water vapor  Surface scanning for cloud, precipitation, water vapor, and aerosol  Supporting wind and thermodynamic measurements

19. Role of ATD  HIAPER as a water cycle research platform (in-situ and remote sensing) – requires work with HIAPER, NSF, Water Cycle Initiative, NASA, etc.  Current facilities plus possible expansions Surface measurements to include other listed parameters (how to proceed) Surface measurements to include other listed parameters (how to proceed) Lidar work in water vapor and aerosol (airborne and Lidar work in water vapor and aerosol (airborne andground-based) Reference radiosonde for humidity Reference radiosonde for humidity New remote sensing areas including hyperspectral measurements of clouds and surface properties New remote sensing areas including hyperspectral measurements of clouds and surface properties Improved in-situ measurements of aerosol, cloud and precipitation particles Improved in-situ measurements of aerosol, cloud and precipitation particles Continue on new direction of radar and radiometer studies of cloud properties Continue on new direction of radar and radiometer studies of cloud properties  Work with possible strategic partners for reference sonde, lidar, changes of surface approach and airborne multi-spectral remote sensing

20. Priority Scientific Topics: Weather Jim Wilson/Tammy Weckwerth -- Leads Improved scientific understanding of weather processes with a goal of improved prediction. Research areas include: a) Convection (from “dry” boundary layer circulations to severe weather) b) Extratropical storms, fronts, cyclones and winter orographic precipitation c) Tropical convection/Tropical cyclones d) Fire Weather e) Improving NWP forecast skill of events that are high impact to society f) Air quality and toxic dispersion (see chemistry) g) Data assimilation

21. Observational Needs 1)Measurement needs depend on both phenomena and time-scale of interest 2)Local and mesoscale observations a) Microphysical observations (aerosol, cloud and precipitation) using remote and in situ measurements, b) Surface precipitation c) High-resolution mapping of water vapor, winds, temperature, pollutants/toxins d) Land/air and water/air fluxes of moisture, temperature and momentum. e) Surface meteorology and characteristics (i.e., fuel, moisture, fire perimeter for fire, vegetative index for convection) 3) Move to larger scales and scale-interaction studies also requires a) Wind, thermodynamic, cloud, precipitation and turbulence profiles b) Soundings (rawinsonde and dropsonde) c) Ability to work with modern satellite data (also local and mesoscale)

22. Role of ATD 1)Weather needs encompass current ATD technologies 2)New potential developments include the following goals Winds - Investigate L-band, lidar, FM/CW, bistatic and X-band forward scattering - Investigate next generation of airborne Doppler radar (examine potential for multiple frequencies on same or multiple instruments) - 3-D wind measurements using a scanning radar (MAPR tests) - Enhance numerical retrieval techniques - CASA collaboration for winds, precipitation and thermodynamics Targeted observations of state variables - Continue development of driftsonde and miniaturization of dropsonde - Investigate UAVs with partnerships Water vapor mapping in all weather conditions - Continue to develop DIAL and radar refractivity techniques - Investigate scanning microwave radiometers

23. Role of ATD Discussions with NSF community suggests a need for mobile measurements - Find a way to integrate DOW’s into ATD? - More mobile ISS - Rapid deployment of bistatic receivers Improved measurement and retrieval techniques for fire fuel and fire perimeter Intelligent surface measurements for extensive coverage of meteorological measurements at low cost (ISA as a PAM replacement) Extension of integrated (ISS) approach and examination of the potential for combination of ground-based radar and lidar with passive sensors, such as GPS and radiometers HIAPER -- Dropsondes -- Cloud radar for microphysical and Doppler measurements -- Water vapor and aerosol profiles from lidar -- Accurate in-situ sensors

24. Impressions and Discussion  Need for current ATD measurements continue even in the face of changing institutional priorities and areas of national need  Most, or all, ATD sensing systems would benefit from varying degrees of modification, upgrade or even replacement  Staff has excellent ideas for long-term sensing and technique development for current systems ensuring service to the community and instrumentation leadership Clear air—all weather winds ( Clear air—all weather winds (L-band, lidar, FM/CW, bistatic and X-band forward scattering) 3-d winds for a single Doppler radar 3-d winds for a single Doppler radar Eye safe lidar Eye safe lidar Reference radiosonde Reference radiosonde Miniaturization of dropsonde Miniaturization of dropsonde Driftsonde, etc Driftsonde, etc Giant nuclei systems Giant nuclei systems Turbulence from profilers, expansion of ISS concept Turbulence from profilers, expansion of ISS concept Expansion of in-situ aerosol and cloud particle measurements Expansion of in-situ aerosol and cloud particle measurements

25. Impressions and Discussion  New instrumentation needs arise that cut across research themes Surface measurements -- more variables to be measured with larger number of sensors (do we use ISA, TRAM, flux towers, UAVs, tethered platforms, ships, buoys, etc.) – careful thought is required – T. Horst has drafted a write-up Surface measurements -- more variables to be measured with larger number of sensors (do we use ISA, TRAM, flux towers, UAVs, tethered platforms, ships, buoys, etc.) – careful thought is required – T. Horst has drafted a write-up Strong call for chemistry in the new interdisciplinary areas – biogeo, chemistry, climate and geophys. turbulence have many of the same measurement needs Strong call for chemistry in the new interdisciplinary areas – biogeo, chemistry, climate and geophys. turbulence have many of the same measurement needs Increased need for lidar for the NSF community (aerosol, Doppler, trace constituent – chemistry and water vapor) both airborne and scanning ground-based Increased need for lidar for the NSF community (aerosol, Doppler, trace constituent – chemistry and water vapor) both airborne and scanning ground-based Increased need for mobile measurements in the weather community Increased need for mobile measurements in the weather community Increased need for longer term monitoring – ATD role development and technology transfer or new mission Increased need for longer term monitoring – ATD role development and technology transfer or new mission Importance of CCN, IN, and cloud sensing Importance of CCN, IN, and cloud sensing Increased need for accuracy (partly driven by climate needs) Increased need for accuracy (partly driven by climate needs) Accurate measurements of temperature, winds, and humidity in cloud Accurate measurements of temperature, winds, and humidity in cloud Increased focus of the weather community on both global processes and local high resolution models Increased focus of the weather community on both global processes and local high resolution models

26. Impressions and Discussion  HIAPER – new expertise required Passive hyperspectral and active microwave sensing Passive hyperspectral and active microwave sensing Measurement skill in a compressible environment on different platforms Measurement skill in a compressible environment on different platforms Entrainment of scientific, engineering and technical skills to match arrival of new sensing systems Entrainment of scientific, engineering and technical skills to match arrival of new sensing systems Working with NSF to ensure critical needs are met including filling the gaps in the HIAPER funded instrumentation Working with NSF to ensure critical needs are met including filling the gaps in the HIAPER funded instrumentation  Trade-offs between selecting new areas, continuing needed expertise and data quality  How do we manage both airborne and ground-based remote sensing  Hyperspectral remote sensing expertise will be needed on HIAPER plus how do we deal with the revolution in satellite data, an NSF satellite program?  Little said on real-time data transfers, is this expected (BAMEX and IHOP experiences) or assumed not necessary?  Correct aircraft fleet for the ten year time-scale (UAVs/RPVs, extension of P-3 contract, ELDORA replacement, lifetime of C-130?)  ATD and national (sometimes non-NSF) needs – climate monitoring, weather prediction, homeland security), are we diluting NSF service goals --- ATD mission or the mission of other entities in the Atmospheric Observing Lab?