6. OPERATIONAL LOGISTICS
6.1.1 Scientific Steering Committee
The conveners of the IGAC/ACAPS and MAGE Activities and former convener of the IGAC/MAC activity serve as the ACE-1 Scientific Steering Committee. The Steering Committee provides the overall guidance and management of ACE-1 and is responsible for liaison between the ACE-1 principal investigators and federal agencies and establishing budget priorities. It also has primary responsibility for preparing the ACE-1 Science and Implementation Plan and organizing the measurements on the various observational platforms. The Steering Committee takes its overall direction from the Science Team that is composed of the ACE-1 principal investigators and ACAPS and MAGE committee members. Members of the Steering Committee include:
Timothy Bates, NOAA/PMEL, ship coordinator
Robert Charlson, University of Washington
John Gras, CSIRO, ground station coordinator
Barry Huebert, University of Hawaii, aircraft coordinator
During the field experiment, the Steering Committee will act as the scientific planning team for coordinating and integrating the observations on each platform. The Committee will also monitor and adjust resource utilization and will be responsible for maintaining balance in accomplishing all the ACE-1 objectives. In the postfield-phase, the Steering Committee will publish a summary report of the field experiment, coordinate research and collaboration and organize scientific workshops.
6.1.2 Field Project Management
Dr. C. B. Emmanuel will serve as the Field Operations Director. In this capacity he has the responsibility for the preparation and implementation of the ACE-1 Field Operations Plan and for the coordination and oversight of all ACE-1 Operations Center activities.
The Field Operations Director, supported by the Operations Center Staff will:
Operational details can be obtained from Dr. Emmanuel, UCAR International Project Office, P.O. Box 3000, Boulder, CO 80307, USA, 303 497-8693, fax 303 497-8634, firstname.lastname@example.org.
Ms. Karyn Sawyer, UCAR Joint Climate Projects/Planning Office will serve as the Field Logistics Coordinator. In this capacity she is responsible for:
Logistical details can be obtained from Ms. Sawyer, UCAR Joint Climate Projects/Planning Office, P.O. Box 3000, Boulder, CO 80307, USA, 303 497-8681, fax 303 497-8633, Karyn@ncar.ucar.edu.
6.1.4 Technical Logistics and Data Management
Dr. Richard A. Dirks, UCAR Office of Field Project Support will serve as the Operational Forecast Products and Data/Communications Coordinator. In this capacity he is responsible for:
Data and communication details can be obtained from Dr. Dirks, UCAR Office of Field Project Support, P.O. Box 3000, Boulder, CO 80307, USA, 303 497-8987, fax 303 497-8158, email@example.com.
The Hobart, Tasmania International Airport has been selected as the location of the ACE-1 Operations Center. This facility provides suitable space and support to meet the following project requirements:
close proximity to aircraft operations
access to real time weather data for project specific forecasting
good quality voice and data communications
work space and support (power, environmental control, etc.) for project participants and their equipment
good logistics support (housing, banking, medical care, supplies)
6.2.2 Operational weather forecasts and trajectories
The coordination of ACE-1 observations and the timing of observations require the preparation and continuous updating of weather forecasts and monitoring of current weather conditions. The ACE-1 forecast team will prepare a daily forecast briefing package for the daily planning meeting. This briefing will include short term (0-36 hour) forecasts and forward trajectories that will be critical for operational decisions regarding deployment of observing systems (aircraft and ship) and coordination of sampling times. In addition, mid- and long- range outlooks (36-72 hours) will assist in overall project readiness. The BoM Hobart Office has offered to work closely with the ACE-1 forecast team. Dr. Steve Siems of Monash University in Melbourne will aid in the preparation of forecast trajectories and the analysis of boundary layer dynamics.
Regional data to be used by the ACE-1 forecasters include regional standard analysis charts prepared by the BoM and possibly the Meteorological Service of New Zealand, regional and global model products from BoM, US National Meteorological Center (NMC), European Center for Medium-range Weather Forecasting (ECMWF), and New Zealand. Special aviation and marine forecasts as well as tailored trajectory model forecasts will be prepared during the field program. Data from both geostationary (GMS via BoM McIDAS) and polar orbiting (NOAA AVHRR via the project ground station in Hobart) satellites will be important for monitoring and forecasting as well as subsequent data analysis.
ACE-1 operational data collection will begin on 1 October 1995 to support ship and aircraft transits from the US to Australia. The archive will include surface and upper air meteorological data as well as model data from BoM, NMC and ECMWF. Research data collected on the ship and aircraft during the transits also will be part of the final ACE-1 data archive.
ACE-1 will require good quality voice and data communications to assure successful coordination of aircraft, ship and land-based operations. Long range commun-ications between the ship, aircraft, and the Operations Center in Hobart will be handled by a digital HF system in which matched transmitters & receivers automatically step through frequencies and baud rates until high-quality transmissions are achieved. As needed, satellite based voice and data commun-ications can also be used between the ships and Hobart. The ACE-1 operations center in Hobart will be connected to the international Internet system via the Australian AARNET (Australian Area Research Network) and will have a local area network (LAN) within the operations center facility to permit data exchange, electronic mail and other activities.
The value of a multiplatform experiment depends critically on being able to compare data from many different investigators and their many instruments. The ACE-1 science team is therefore arranging for both laboratory and field intercomparisons of all the major sampling systems whose comparability will be critical. The laboratory workshops, which will be designed to resolve questions about calibrations and techniques without uncertainties due to platforms and slightly-differing field locations, will be run before the field campaign. The field comparisons will be conducted by sampling or sensing from co-located platforms both early and late during the field intensive portion of ACE-1.
6.3.1 Impactor Intercomparisons (coordinated by P. Quinn)
The measured mass size distributions will provide information on the size dependent chemistry of the aerosol and will serve as input data to model calculations of aerosol dynamics. Several different types of impactors will be used during ACE-1. These include MOUDIs, Berner-type cascade impactors, and Sierra High-Volume impactors. The three types of impactors were intercompared during the Pacific Sulfur/Stratus Investigation in 1991 (Howell et al., 1995). An additional intercomparison of Berner-type impactors and Sierra High-Volume impactors is being held in Seattle during the summer of 1995.
The intercomparison will consist of three parts. The first stage will involve each group a) analyzing the same standard stock solution of major anions and cations and b) extracting and analyzing a filter which has been spiked with a known amount of stock solution. The second stage of the intercomparison will be the operation of the impactors in unison outside at PMEL for a comparison of their sampling performance at ambient relative humidity. Tests will also be performed to determine if reliable impactor data can be collected at low humidity for comparison to the physical aerosol measurements.
6.3.2 Aerosol Sizing, CN and CCN Intercomparisons (coordinated by D. Covert)
A critical component of the ACE-1 will be the measurements of aerosol size distrib-utions, total CN with different lower size cuts, and CCN at various super satur-ations. Two workshops are being held during the summer of 1995 to test critical parameters and evaluate instrument performance. The first workshop was held in Leipzig, Germany (July 1995) to evaluate DMA transfer functions and charge neutralizers. A second laboratory workshop will be conducted in Seattle, Washington (August 1995) to compare the response of the CN, CCN and DMPS’s that will be used during ACE-1.
6.3.3 SO2 measurement intercomparisons
The NASA CITE-3 program demonstrated that most gas-phase sulfur measurement techniques were capable of accurately measuring the concentration of the various sulfur gases (Hoell et al., 1993). The one notable exception was SO2. Considerable progress has been made in SO2 measurement techniques since CITE-3 and an intercomparison of the GCMS-ILS, HPLC fluorescence, filter pack ion chromatography (IC), mist chamber IC, API-MS, and fluorescence techniques was conducted at the University of Delaware between 15 September and 15 October, 1994 under the sponsorship of the NSF.
6.3.4 Aerosol sampling protocols (coordinated by J. Ogren)
Quantitative comparison of the results from the various ACE-1 participants requires that the aerosols are sampled in a consistent fashion. The following sampling standards have been adopted:
2. The common size cut between coarse and fine aerosol will at an aerodynamic diameter of 1.0 mm (RH < 50%).
3. A common upper size cut of 10 mm aerodynamic diameter (RH < 50%) will be used for coarse and “bulk” aerosol samplers and instrumentation.
4. Single supersaturation CCN instruments will use a common supersaturation of 0.5%.
The development and maintenance of a comprehensive and accurate data archive is a critical step in meeting the goal of ACE. The overall ACE data management philosophy is to make the completed data set available to the world research community as soon as possible in order to better incorporate aerosols into global climate models. A centralized data archive will be established to combine the entire ACE-1 data set. This integrated data base will allow users a single access to the variety of measured and derived fields obtained during ACE-1. The UCAR OFPS is responsible for developing this combined archive based on input from the ACE-1 Science Team. In addition, an on-line catalog system will be used during the filed phase to assist PIs in cataloging and retrieving preliminary data. Details of the archive are contained in the ACE-1 Data Management Plan.
During the Seattle ACE-1 planning meeting, the ACE-1 Science Team formulated the following data protocols:
2. All investigators participating in ACE-1 must agree to promptly submit their data to the central data base to facilitate intercomparison of results, quality control checks and inter-calibrations, and an integrated interpretation of the combined data set.
3. All data shall be promptly provided to other ACE investigators upon request. ACE investigators are those included in this document and/or those directly participating in the field experiment.
4. During the initial data analysis period (one year after the data have been processed to their final form, but no later than December 1997), no data may be provided to a third party (journal articles, presentations, research proposals, other investigators) without the consent of the investigator who collected the data. This initial analysis period is designed to provide an opportunity to quality control the combined data set.
5. It is the intent of the ACE science team that all data will be considered public domain two years after the end of the field experiment and that any use of the data will include either acknowledgment or co-authorship of the investigator who collected the data.
6.5.1 Future ACE-1 meetings
The first four ACE-1 planning meetings succeeded in defining the experimental objectives and in outlining the research plan. The results from these meetings have been summarized in this science and implementation plan. We hope that this plan will continue to stimulate interest in the ACE experiments and will serve as a planning document for individual investigators seeking support through their national channels.
The first ACE-1 data workshop is scheduled for July 1996 in Seattle. This workshop will give ACE-1 investigators an opportunity to discuss preliminary data and to plan presentations for a special session at the December 1996 AGU meeting in San Francisco. A second data workshop will be held in the spring of 1997 to integrate the finalized data sets. A second special ACE-1 session will be held at the IAMAS Assembly on 1-9 July 1997 in Melbourne, Australia.
ACE-2 is planned for the North Atlantic in order to compare the unpolluted remote marine boundary layer results of ACE-1 with the anthropogenically perturbed aerosol flowing off Europe and Africa. The experiment will be conducted from June 15 to July 31, 1997. The Science and Implementation Plan for this experiment is available from Frank Raes, Environment Institute, Commission of the European Communities, 21020 Ispra (VA) Italia, 39-332-789300, Fax 39-332-789453, Internet: firstname.lastname@example.org or Timothy Bates, NOAA/PMEL, 7600 Sandpoint Way NE, Seattle, WA 98115, USA, 206-526-6248, Fax 206-526-6744, Internet: Bates@pmel.noaa.gov. The next ACE-2 organization meeting is planned for February 1996 in Ispra, Italy.