Report on the ACE-Asia Science Team Meeting

Kunming, China, 11-13 November, 1999

Prepared 12 January 2000

The meeting opened with welcoming remarks by our host Professor Wang Mingxing

A. Presentations summarizing the scientific issues for ACE-Asia

ACE-Asia Overview and Goals - Barry Huebert

Barry talked about the ability of global and regional aerosol models to represent reality. Sulfate data from MLO in the mid-Pacific was used as an example: the ECHAM3 GCM-based chemical transport model nicely predicts the observed seasonal cycle of NSS, while the newer ECHAM4 model badly over-predicts it (by a factor of 2 or 3). Yet the E4 model, when run nudged towards actual meteorology, correlates surprisingly well (R2 = 0.73) with day-by-day NSS observations. Since neither of these models includes heterogeneous removal by dust or seasalt, it is possible that E3 is right for the wrong reasons: if its vertical transport (BL to FT) were too small, this could compensate for the lack of those heterogeneous removal mechanisms operating on the SO2 leaving Asia.

How should we test models to identify the best ones to use for various purposes? Street et al. (Ambio, 28, 135-143, 1999) compared several published, well-respected models of China’s impact on aerosols in Japan. One said China was responsible for 17% of ambient aerosol in Japan; a second said 3.5%; while a third simulation said >50%! Obviously this wide range would leave policymakers wondering whether any of these tools is an adequate basis for decision-making. We must design our observations so they form the best tests of these models and the process rates them employ.

 Mineral Aerosol, Evolution and Impacts - Irina Sokolik Irina emphasized the need to do measurements very well at a small number of targeted stations. The stations should include an unpolluted dust site (near a source region), a site where dust and pollution have interacted, and one or two sites in marine regions, where the interaction between dust and sea salt can be studied. Each of these sites should include measurements of size-dependent chemistry and mineralogy, scattering and absorption, and radiative fluxes.   Irina presented new model simulations demonstrating that interaction of dust with other atmospheric species might result in the formation of multicomponent aerosols which have drastically different optical properties and, hence, radiative impact, from those at the dust source. Urban/industrial Species, Photochemistry, Regional Modeling - Greg Carmichael Greg’s group has already done extensive modeling of nitrogen, sulfur, dust, and black carbon transport and removal in Asia, using the RAINS-Asia model and several meteorological processors. he described some good examples of testable predictions, including one that particulate nitrate will be transported farther off shore than NSS will. he also noted that NH3 and the dust size-distribution are both critical for controlling process rates in the Asian outflow, so both should have a high priority for measuring platforms. Their lab work shows that the reaction of HNO3 with dust changes both the shape and f(RH) dramatically, so we need to look for evidence of these processes in the atmosphere. Process Studies and Lagrangian Modeling - Céline Mari Celine described the impressive capabilities their group has developed for supporting Lagrangian experiments and interpreting their results. Their post-experiment modeling has shown, for instance, that oxidation on sea salt is critical for explaining the loss of SO2 during ACE-1. They also note that Liss and Merlivat explain DMS fluxes much better than Wanninkhof does if you assume OH is the only oxidant for DMS, but that if you consider possible halogen oxidants the two flux parameterizations perform equally well at predicting observed DMS concentration changes with time.

Using historical meteorological data, they predict that the South China Sea and surrounding regions usually have multiple starting points each day for successful two-day Lagrangian experiments. The trajectories frequently bend southward after leaving China or Japan, so they usually don’t move so far east that they cannot be reached by the C-130. Although the NSF has indicated they will not support balloon-tagged Lagrangian experiments of the type used in ACE-1 and ACE-2, we will want to watch the evolution of airmasses from day to day and this modeling capability will be important for doing so.

 Satellites and Radiative Transfer - Teruyuki Nakajima Terry summarized the satellites against which we could compare our in situ measurements. he also noted that his model and others are predicting a Northern Hemisphere optical depth of about 0.2. he has evidence that TOMS seems to under-predict the Asian optical depth, and speculated about the reasons for this problem. He also noted that the effective radius of cloud droplets (Re, as inferred from AVHRR) has decreased over the last 10 years. Is this trend due to increasing aerosol emissions form Asia? If so, how could we test the retrieval of Re, to confirm that this trend is real? Aerosol Organics - Why Measure and Speciate Them? - John Seinfeld & Bernd Simoneit John noted that EC/OC measurements, while highly uncertain, are a fundamental measurement that is essential. We need to know the vertical and regional distribution of EC and OC, and should measure them in the most artifact-free ways possible. The next step for understanding organic aerosols is to measure their optical and hygroscopic properties and molecular speciation. As organic vapors are oxidized to condensible species, they add polar groups, and this polarity means that they are likely to affect both the surface tension and solubility terms in the Kohler equation that is used to infer indirect forcing. Functional group analyses and solubility methods offer great promise for understanding these effects.

Bernie noted that molecular markers can be used to identify the source of aerosols. He can easily distinguish between natural plant waxes from the residues of biomass burning and the combustion of fossil fuels in coal or oil-fired power generation, cooking, and forest fires. These molecular markers can be very helpful for tracing the history of the organics found in various samples.

 B. National Reports
[Note: Some of the national Reports have been written out in detail by their presenters, and have been posted to the web page. We briefly summarize all the reports below.]

China - Shi Guangyu – new Chinese coordinator

Proposal has been submitted to NNSFC for Cloud-aerosol-radiation study
No national funding at this time, but ACE-Asia work may be included in a China-Japan Kosa project for 2000-2005.
Chinese researchers will focus on NSS, Mineral aerosol, and BC.


Japan - Kimitaka Kawamura

Uematsu has funding from CREST/STA
In April 1999 a proposal was accepted by Monbusho for ACE-Asia planning
In May 1999 a proposal was submitted to STA/Frontier for ACE-Asia funding.
Two cruises are planned for 2000 (see web page)


Korea - Young J. Kim

Ongoing measurement program includes:
Atmospheric composition changes (Kosan, Ahmyundo).
Long Range Transport study (6 sites, PM 2.5 sampling every 6 days) and includes both airborne and ship/ship measurements
LIDARs at 4 sites
Planned measurements
They will upgrade Kosan Site to support more visitors. Dr. Sung-Nam Oh will be in charge of the site, with assistance from Dr. Chun.
A new Advanced Environmental Monitoring Research Center (ADEMRC) has been funded. some of this will be directed at ACE-Asia.
Proposing large integrated program to start in 2001.
Korea will provide radiation/optical measurements listed in the network S&IP. Some instruments that are currently in Seoul will be moved to Kosan
Their aircraft, which has mostly worked west of Korea., will integrate its flights with the other AA aircraft.


Chinese Taipei - Tai Chen

Three sites are being planned: Mt. Bamboo at the northern tip, Lan Yu in the southeast, and Wan Li (which will only operate during the spring IOP)
An extensive set of measurements will be made, including composition vs size, EC/OC, organic speciation, gaseous precursors, radiation, etc.
Several aerosol effects and process models will be used.
See web page report for details. USA - Tim Bates Survey & Evolution and Network Science Plans were reviewed together by NSF/NOAA – The six reviews were generally thoughtful and positive and recommended funding after deficiencies are addressed. Unfortunately shortened science plans did not clearly define the four ACE-Asia components which confused the reviewers.

Primary NSF/NOAA concerns:

Ability to accomplish Lagrangian experiments

reviewers felt we would be too far (200 nm) from the sources (dust and pollution) to observe changes. NSF has decided not to fund Lagrangian experiments. Radiation closure should be included in this first survey intensive increase priority for sunphotometers, radiometers and satellites The aircraft need(s) an inlet that will pass large particles aircraft proposals will not be funded until low-turbulence inlet (LTI) capabilities are demonstrated US network operations should focus on 1 or at most 2 supersites and focus on  characterization as opposed to budgets and fluxes
 

Timetable:
    1. Proposals due to NSF (NOAA only if NSF is not an option) by January 31, 2000
    2. All proposals will be reviewed and prioritized
    3. Non-aircraft proposals can be funded with FY 2000 money (before July 15, 2000)
    4. Aircraft proposals could be funded in early FY 2001 (November 2000) if aircraft LTI passes tests
    5. Current plan is to fly LTI on the NCAR Electra in spring of 2000 for turbulence tests and on the NCAR C-130 in summer of 2000 for aerosol passing efficiency tests using both dust and sea salt ambient aerosols. The testing is being planned, executed, and evaluated by a LTI Assessment Working Group, whose initial plan/report is posted on the ACE-Asia web site.
Australia - Jorg Hacker
Radon samplers at 4 grounds stations
Hilton Swan is interested in providing DMS measurements at a ground site
Jorg Hacker, Steve Siems, and Jorgen Jensen have partial funding to bring the King Air to the 2001 Intensive. Goal will be to study how fronts process aerosols. Plane may be able to fly over China. Still need additional funding.
High altitude Grob Egret aircraft is available for $1,500/hr. Minimal deployment is $120K.


France - Daniel Martin

Their emphasis is on the source regions, especially for dust and BC/OC.
More interested in long-term measurements than intensive ones.
See web page report for details.


UK - Tom Choularton

No large UK ACE-Asia project in 2001, but PIs will participate in 2001 under individual grants.
There is a proposal to NERC to replace the UK C-130 with a BA146, but 2002 or 2003 is the very earliest it could do experiments.
Their interests are primarily in hillcap and frontal cloud studies. Canada - Sunling Gong
Will have modeling component
Could bring LIDAR to Kosan if funding available


Russia – Igor Granberg

Would like to use the Russian railroad car lab if possible. It has 3 years of funding, but may have other obligations during the 2001 intensive. C. Related Programs

NASA TRACE-P – Barry Huebert

TRACE-P will bring the NASA DC-8 and P-3 to the region in April/May 2001. Their goals are very similar to ACE-Asia, but with a much greater emphasis on photochemistry. Both groups have indicated a desire to conduct joint flight operations and to collaborate in a variety of ways.
The TRACE-P aircraft will probably spend about 3 weeks based in Hong Kong and 3 weeks based at Yokota, near Tokyo. China MAP - Mike Bergin Although China-MAP is to expire this year, a proposal has been submitted to continue some of their operations into the time ACE-Asia will be operational. The Lin’an site is one where joint observations would be very sensible, since it is in the pathway of dust events that move to the southeast. Terra/EOS/MOPITT - Jinxue Wang No report; presenter had to participate in launch of satellite. However, there is an intent to collaborate with the EOS program and find ways to share data. PACE-7 - Kikuo Okada
Field program in February 2000, Project ends April 2000
Using G-2 aircraft to examine spatial distribution of aerosols, EC, CO, O3, and ssp over Pacific, mostly in the FT
NASA ACMAP Modeling - Mian Chin
Proposing GOCart model to evaluate AA observations
NRA included ACE-Asia as a topic for funding


Lidar Network - Nobuo Sugimoto

The Japanese KOSANet has been expanded to include Korean and Chinese lidars.
The group met in August
Eight Japanese lidars will operate during ACE-Asia.
Continuous, 2-wavelength lidars will be operating during the IFO at Tsukuba, Chichijima Island, and on the R/V Mirai. The Tsukuba lidar has operated continuously since 1996. APARE – Rich Arimoto and Mitsuo Uematsu The IGAC APARE Activity Committee met in Hawaii in June, 1999. They formally endorsed both ACE-Asia and TRACE-P as IGAC/APARE experiments. D. Status of ACE-Asia Components & S&IP Documents

D.1. Network Time-Series Operations - Rich Arimoto

See web page


D.2. Survey and Evolution, AA-SEC - Barry Huebert
 

Platforms
PIs interesting in working on platforms should contact platform coordinator.
US: NOAA/UNOLS ship – initial request made, final request will go in 31 Jan.
US: NCAR C-130 – available pending support (which depends on LTI inlet tests)
US: CIRPAS Twin Otter– available pending support
Japan: Mirai 7-21 May (in area), 1 June – 14 July (north) 2001
Korea: aircraft flight over Yellow Sea
Korea: ship, Yellow Sea, in springtime
China: aircraft probably not available in 2001
China: helicopter could be leased
     Aircraft could be leased at 4000RMB/hr
Australia: ARA Kingair half funded but committed
     Could possibly fly in China
Ground stations in intensive mode
LIDAR network in intensive mode (data on web site)
Participants:
Suggested additions/changes to measurements listed in tables in Science and Implementation Plan
Ship:
Keene et al. (reactive Cl gases, ammonia, CO, reactive halogens, SO2, nitric acid, hydrogen peroxide, ozone, CH2O, HCOOH, CH3COOH, radiation, hi-vol sized aerosol)
SJAC instrument (Peking University)
Tanaka, Akimoto (halogen oxidants)
Wang Charlie, NCU (NMHC, CFC)
C-130:
Drum sampler for trace metals and organics
CO, NMHC, NH3, HNO3 moved to higher priority
CVI
What sources are impacting regions: apportion aerosol to sources using fingerprinting by organic species
D.3. Aerosol-Cloud Experiment - Tom Choularton
Cloud experiment in 2001
  1. Frontal clouds (Kingair) Hudson to add CCN instrument
  2. Hillcloud study on Cheju – CCN, hygroscopic growth (Sweitlicki), Kingair - Proposal to NERC for Kingair flight time and measurements on top of mountain, proposal to be submitted in June, outcome in September
  3. Individual cloud studies (Kingair)
  4. Remote sensing study (Nakajima)
Goals:

To establish the relationship between the initial particle size distribution and chemistry, the CC N activity spectrum and the CD size distribution.

To investigate the relationship between cloud albedo, the vertical distribution of CD size distribution and the properties of the aerosol and to what extent are the cloud microphysical processes controlled by dynamical processes such as entrainment.

How does cloud processing of aerosol affect the microphysics of clouds formed on the processed aerosol

To determine functional relationships between aerosol properties and cloud microphysics which can be used to determine effective parameterizations.

To determine the relationship between the aerosol properties, the onset of precipitation and cloud extent.

 E. Working Group Meetings

Working groups met in three sessions during the second day of the meeting. Some prepared detailed reports, such as that from the Network Sites which is now on the web. For some groups we have brief notes below, but for a few we are still awaiting a written report.

AA-SEC WG – Huebert

See status report above in D.2.


Network Sites WG w/ Chemical sizing and Inlets WG– Arimoto

See detailed summary on web page.
Super-sites:
Beijing, Yulin (at the Zhen Bei Tai remnant of the ancient Great Wall),
Qingdao, Lin’an in that order in China
Kosan, one downwind site in Japan (Hachijo?)
Size cut issue:
We recognized that data with a single cut is of limited value, but much easier to use than bulk concentrations. Supersites will have size resolved impactor sampling, while other sites will use the IMPROVE sampler, which can easily be modified for the desired 1 um cut.
Operational Issues:
Samples will be exchanged institution to institution (IAP-U.Hawaii), Data – need to establish archive.


Radiation and Satellites WG w/ Optical Properties WG – Nakajima

Clouds and Aerosols WG – Choularton

See summary in D.3.
Modeling WG – Carmichael & Seinfeld
See report on web site


Ions WG (No meeting; summary prepared by Quinn from email discussion)

This group will deal with inter-laboratory IC standardization issues and prepare blind intercomparisons.
Korean group will be reduced to two
Add: Tom Cahill (tacahill@ucdavis.edu), China Map (Mike Bergin, contact), Y.S. Wang (ysw@linex2.iap.ac.cn), Jian Yu (chjianyu@ust.hk), ctlee@cc.ncu.edu.tw, Tanaka, Mitsuo Uematsu. Organics - Kawamura & Cahill Possibility of intercomparison in Japan next year. Aircraft issues- Jensen Where can the aircraft fly? There are difficult issues with military warning zones in the Yellow Sea that will limit the times we can fly there.
Hiroshima might be best base. (Iwakuni MCAS was selected based on a post-meeting site survey.)
Kingair might be at Cheju sometime.
To gather samples from above the surface in a dust source area, the ARA will request clearance to fly the Kingair near Xi’an.
Sampling from helicopter and aircraft – Kingair could fly with TAS to get dust samples, but a helicopter may disturb the air too much
Need: Strong Chinese collaborators and instruments, Diplomatic clearances, Funding Mineral Aerosol - Arimoto and Anderson Need size resolved concentration data and mineralogy
Need to distinguish mineral aerosol from fly ash,  Trace metal with PCA and TEM/SEM could maybe be used to calibrate region so that trace metal analysis could be used on routine basis
Need to distinguish agricultural from "natural"
Methods:
SEM, TEM, STEM, TOFMS, XRD, XRF, PIXE, ICPMS
Need size segregated sampling, look at ratio of PM10/PM2.5 to determine what samples to analyze
Carmichael wants samples for surface area and density. Lidar Network WG – Sugimoto

Meteorology WG- Merrill

Operational issues related to forecasting and acquiring model output were discussed with JOSS. F Details and Implementation:

Operations Center, communications, logistics - Karyn Sawyer & Dick Dirks of JOSS

A site visit was to be conducted after the meeting to select an Operations Center site and location to base the aircraft. that has resulted in the choice of Iwakuni MCAS, just SW of Hiroshima, as the Operations Center. This US Marine Corps facility has ample space for aircraft, offices, meeting rooms, workshops, and portable laboratories. All the offices and meeting rooms are wired for the internet, so it will be very convenient for running forecast models as well as communicating with the other platforms and surface sites. Non-US nationals will have complete access to the Ops Center as long as clearances are obtained in advance.

The JOSS staff will be issuing informational bulletins regarding various shipping, customs, and health issues prior to the field program. It will be essential that PIs using their services respond promptly to requests for information about materials that will need to be shipped, etc.

 Data Policy & Data Base Issues A Data Management Committee was formed to discuss issues of data access. The committee will be chaired by Dick Dirks (JOSS-UCAR) and will include the national committee representatives, the ground site coordinators and the project meteorologist, John Merrill.

One of the delicate issues that needs to be resolved fairly soon concerns the ability of ACE-Asia PIs to obtain data being gathered routinely by various governmental agencies. Can we assume, for instance, that all the met data being collected at Kosan and other sites throughout Asia will be sent to the ACE-Asia archive? The agencies collecting that data may be willing to share it, but they have no obligation to do so. When we identify routine monitoring data that we cannot be assured of getting, we need to arrange to make our own measurements so that all ACE-Asia PIs can find that data in our archive.

 A Note of Appreciation The meeting was held at the Longdu International Recreation Resort, close to the Kunming Botanical Gardens. We spent the last afternoon at the beautiful Kunming ’99 International Horticultural Exhibition. Special thanks are due to the entire Chinese organizing team, and especially to our hosts, Prof. Wang Mingxing and Ms. Wang Xiaobai, who handled many of the logistical arrangements. Without their long hours of work, we would not have been able to hold such a productive meeting. Participants

All available address information for the 68 participants can be found on the ACE-Asia web site.

China (17)
Guang-yu Shi
Ming-xing Wang
Renjian Zhang
Xiao-ye Zhang
Yi Liu
Chun-sheng Zhao
Fu Ming
Kesheng Shao
Jie Tang
Lingxi Zhou
Runtian Song
Zhi-Bao Shen
Wang Zijun
Xi-hong Wang
Pucai Wang
Yunfen Luo
Zixia Shi
 

(USA) 25
Barry Huebert
John Porter
Tim Bates
Karyn Sawyer
Richard A. Dirks
Si-Chee Tsay
Ji Qiang
Richard Arimoto
Lynn M. Russell
Anne- Marie Schmoltner
Kevin D. Perry
James G. Hudson
James R. Anderson
Thomas A. Cahill
Irina N. Sokolik
Mike Bergin
Gao, Yuan
John Merrill
John H. Seinfeld
Mian Chin
David Carlson
William C. Keene
Alan Bandy
Bernd Simoneit
Greg Carmichael

(Japan) 6
Kazuhiko Miura
Teruyuki Nakajima
Mitsuo Uematsu
Yi Liu
Nobuo Sugimoto
Kimataka Kawamura

(UK) 2
Tom Choularton
Keith Bower

(Australia) 3
Wlodek Zahorowski
Jorg Hacker
Jorgen B. Jensen

(Chinese Taipei) 3
Chung-Te Lee
Neng-Huei Lin
Tai-Yih Chen

(France) 4
Celine Mari
Helene Cachier
Daniel Martin
Laurent Gomes

(Korea) 4
Chang Soo Chung
Young J. Kim
Youngsin Chun
Chul-Jin Park

(Hong Kong) 2
Wang Tao
Jianzhen Yu

(Canada) 1
Sunling Gong

(Russia) 1
Igor Granberg