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
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
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
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
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
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
Their aircraft, which has mostly worked west of Korea., will integrate
its flights with the other AA aircraft.
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
Chinese Taipei - Tai Chen
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
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
Australia - Jorg Hacker
Proposals due to NSF (NOAA only if NSF is not an option) by January 31,
All proposals will be reviewed and prioritized
Non-aircraft proposals can be funded with FY 2000 money (before July 15,
Aircraft proposals could be funded in early FY 2001 (November 2000) if
aircraft LTI passes tests
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.
Radon samplers at 4 grounds stations
Hilton Swan is interested in providing DMS measurements at a ground
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
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
More interested in long-term measurements than intensive ones.
See web page report for details.
No large UK ACE-Asia project in 2001, but PIs will participate in
2001 under individual grants.
UK - Tom Choularton
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
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
Russia – Igor Granberg
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
PACE-7 - Kikuo Okada
Field program in February 2000, Project ends April 2000
NASA ACMAP Modeling - Mian Chin
Using G-2 aircraft to examine spatial distribution of aerosols, EC,
CO, O3, and ssp over Pacific, mostly
in the FT
Proposing GOCart model to evaluate AA observations
NRA included ACE-Asia as a topic for funding
The Japanese KOSANet has been expanded to include Korean and Chinese
Lidar Network - Nobuo Sugimoto
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
D.3. Aerosol-Cloud Experiment - Tom Choularton
PIs interesting in working on platforms should contact platform
US: NOAA/UNOLS ship – initial request made, final request will go in
US: NCAR C-130 – available pending support (which depends on LTI inlet
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)
Suggested additions/changes to measurements listed in tables
in Science and Implementation Plan
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)
Drum sampler for trace metals and organics
CO, NMHC, NH3, HNO3 moved to higher priority
What sources are impacting regions: apportion aerosol to sources using
fingerprinting by organic species
Cloud experiment in 2001
Frontal clouds (Kingair) Hudson to add CCN instrument
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
Individual cloud studies (Kingair)
Remote sensing study (Nakajima)
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–
See detailed summary on web page.
Beijing, Yulin (at the Zhen Bei Tai remnant of the ancient
Size cut issue:
Qingdao, Lin’an in that order in China
Kosan, one downwind site in Japan (Hachijo?)
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.
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
This group will deal with inter-laboratory IC standardization issues
and prepare blind intercomparisons.
Ions WG (No meeting; summary prepared by Quinn from email
Korean group will be reduced to two
Add: Tom Cahill (firstname.lastname@example.org),
China Map (Mike Bergin, contact), Y.S. Wang (email@example.com),
Jian Yu (firstname.lastname@example.org), email@example.com,
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,
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"
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.
All available address information for the 68 participants can be found
on the ACE-Asia web site.
Richard A. Dirks
Lynn M. Russell
Anne- Marie Schmoltner
Kevin D. Perry
James G. Hudson
James R. Anderson
Thomas A. Cahill
Irina N. Sokolik
John H. Seinfeld
William C. Keene
Jorgen B. Jensen
(Chinese Taipei) 3
Chang Soo Chung
Young J. Kim
(Hong Kong) 2