Project ABC
Science Team Meeting
November 4-5,
2002 at the Scripps Institution of Oceanography
La Jolla,
California
Chairs:
J. Fein and A. P. Mitra
Rapporteur: E. Wilcox
The
first session of the Project ABC meeting included a series of talks outlining
the major scientific issues facing the Project and the status of
V.
Ramanathan (SIO/UCSD)
Origins
of Project ABC arose from results of INDOEX which indicated that there was much
more work to be done on the pollution emanating from the region. The first document related to the Project is
the concept paper by Ramanathan and Crutzen (May 2001). The first Project ABC meeting occurred in
London (August 2002) and coincided with the release of the UNEP Climate Impact
report.
Project
ABC aims to address the emissions of air pollution (including smoke, haze, CO,
NOx, CH4, hydrocarbons) and their impacts. Direct impacts are regional and global
climate forcing as well as health effects.
The Project will seek to address natural responses to climate forcing,
paying particular attention to impacts on water resources. The Project will also seek to address the
health impacts.
C4 and UNEP are the primary
coordinators for the Project. The
funding strategy for science involves grants from national agencies to the
individual researchers, including contributions from several nations in Asia
hosting potential observatory sites. The
science consists of observations and impact studies, which will ideally guide
policy decisions related to educational activities, sustainable development,
etc…
Future
research will rely upon observatories based on the Kaashidhoo Climate
Observatory model. This INDOEX station
monitored aerosol radiative forcing (documenting significant reductions in UV and
photosynthetically active radiation at the surface) and chemical
composition. Other key research results
have included satellite observations of direct microphysical suppression of
rainfall by aerosols, and model simulations of regional shifts in precipitation
resulting from INDOEX observed radiative forcing.
Major
topics for Project ABC discussions:
a)
Priority topics of research for next 3 years, including:
- source characterization/upstream effects
- aerosol composition and contribution to radiative effects
- regional aerosol models
- observationally-based estimate of regional aerosol forcing for
all of Asia
b)
Selection of surface observatory sites
c)
Regional and global assessment, including:
- water budget of the wet-season monsoon
- agriculture, such as rice productivity at regional scale
- health impacts
S.
Shrestha (UNEP)
Support
and resources for ABC have been expressed by: Asian Development Bank, Maldives,
China, Japan and European partners. A
goal for this meeting should be the development of a plan with cost estimates
so that development for the observatories may continue in conjunction with the
supporting nations.
G.
Charmichael (U. of Iowa)
Key
scientific issues related to aerosol emissions include:
- linking emissions to specific human activities,
- characterizing “total” emissions, in addition to the
anthropogenic component (e.g.,
separating natural dust from resuspended dust and separating biofuels from
biomass).
Variability
in economic sectors across Asia contributes to tremendous regional variability
in emissions.
Though
emissions inventories are starting to be produced that are useful for climate
impact studies, some issues remain:
- under-prediction of CO during high CO events – which has been
linked to under-reporting of emissions from the domestic sector in central/east
China (i.e., the use of low-quality
coal for home heating/cooking),
- representing the latitudinal gradient in aerosol distribution,
- uncertainties (as high as hundreds of %) in OC/BC, as well as
CO,
- representing the 10-50% variability in deposition/transport of
aerosol simply resulting from interannual variability in meteorology.
K.
Prather (UCSD/SIO)
Real-time
measurements of single particle mass spectrometry allows:
- measurements of individual particle size and composition,
- chemical association (e.g.,
mixing state, source identification, aging),
- composition as a function of size,
- high temporal resolution,
- resolving spatial variability (both horizontal and vertical),
- relating to simultaneous gas phase and meteorological
measurements.
Accomplished
with Aerosol Time-of-Flight Mass Spectrometer (ATOFMS).
Determining
the +/- ion spectra can distinguish the origin of dust or carbon by identifying
the elements present in the particle.
Markers (or fingerprints) have been developed to determine source
characterization (e.g., detection of
a biofuel signal) which are linked to a source region with airmass
trajectories. The approach is also
capable of detecting dramatically different source signatures over small
distances.
A.
P. Mitra (National Physical Lab, India)
Post-INDOEX
activities in India have been directed at:
- developing observing stations,
- establishing international traceability, and
- determining upstream trajectories.
New
observing stations have been developed at: Hante (at ~15,000 ft altitude),
Delhi, Darjeeling (at ~8000 ft. altitude), Sundarbans, and Port Blair.
Emissions
from slash/burn activities in Andrea Pradesh is now studied annually.
Institutional
arrangements are being made to reduce the uncertainties in emissions factors.
Coal
and diesel dominate black carbon emissions in India, however biofuel activity
is highly uncertain; as is its contribution to Indian BC.
The
CO emissions reported in the UNEP report have been revised to lower values.
India
is pursuing new a new automobile policy to reduce emissions from diesel
vehicles.
Additional
modeling efforts are required:
- chemical modeling is available to some extent,
- climate modeling efforts need to be expanded,
- modeling of impacts needs much more attention.
M.
Thiemens (UCSD)
Studies
of sulfates and nitrates using measurements of mass-independent isotope
fractionation:
- indicate a production of large sulfate particles in the ITCZ
that cannot have been transported from India,
- indicate a 35S signal that can only be supplied from
the upper troposphere,
- can distinguish nitrates resulting from gas-phase reactions from
those of soil origin.
H.
Akimoto (Inst. for Global Change Research, Japan)
Results
from ground stations in Japan, China and Europe.
NOx
emissions are growing in East Asia while declining in West. Asian emissions are now greater than
Europe. In Europe during winter,
low-level background ozone and photochemically aged ozone levels are equivalent
and the trends are flat. In summertime,
photochemical component is higher than background and increasing year-to-year.
In
Japan, spring/summer photochemical ozone component is increasing, however
wintertime airmasses originate over the continent and ozone levels are 2-3
times higher than summertime values (which are oceanic airmasses).
In
Thailand, CO and O3 are low in the summer wet season and high in the
wintertime owing to biomass burning.
Wintertime CO levels peak at night, while O3 levels peak in
daytime. Summertime diurnal variability
is low.
W.
Collins (NCAR)
The
first operational aerosol assimilation model has been developed and is
presently being updated to assimilate all modern NASA data (e.g., ICEsat, Calipso, MODIS, MISR).
Blending
the aerosol assimilation with global models is used to compute climate
forcing. Furthermore, model/assimilation
differences are used to reveal model errors.
Can be used as a “transport” GCM that can also be used in “climate”
model in order to separate errors associated with aerosol parameterizations
from errors associated with GCM meteorology.
Major
sources of error in aerosol assimilation are:
- source characterization,
- production of secondary organics,
- importance of mixing assumptions (internal/external),
- processing during transport,
- cloud/precip./aerosol interactions.
The
assimilation (and other models) provides profiles of aerosol, however the only
global dataset available for validating aerosol profiles is SAGE. Though 80% of aerosols reside below 5km, SAGE
only observes aerosols residing above 5km.
That is, SAGE can only measure aerosols that are able to live longer
than about 100 days.
Intersections
between NCAR and other U.S. agencies will be pursued through Project ABC to
provide improved aerosol assimilations.
Many of these efforts will be geared to quantify errors in models, as
much as to provide useful analyses.
November 4 Afternoon Session
“Status of Observations and
ABC Observatories”
Chairs:
P.J. Crutzen and H. Rodhe
Rapporteour:
S.A. Guazzotti
Several
presentations highlighting the state of current and planned observations in the
Indo-Asia-Pacific region, together with descriptions of potential ABC observatories,
were presented in the afternoon session of the Project ABC Meeting. A brief summary
of the major points addressed by the different researchers is presented below.
Dr.
Podgorny presented a general overview of available surface monitoring sites in the
Indo-Asia-Pacific region making reference to the corresponding report prepared
for this meeting. Additional information showing results of cluster analysis of
7-day back trajectories (500 mb and 700 mb) on each observatory location were
introduced from an additional report. The information on the present state of the
observatories was collected mostly from Internet web-sites and communications
with interested parties. Dr. Podgorny mentioned that the report will be made
public in the ABC web-site after the conclusion of the meeting and the revision
of the present document. In the report, observatories are divided between
Global and Regional Networks. Interrelation among networks was highlighted by
Dr. Podgorny with examples from both global (e.g., overlap among the GAW
network, BSRN, and AERONET) and regional networks (e.g., APEX, ADEC, and
ACE-Asia/ TRACE-P). Dr. Ramanathan indicated that the report was requested in
the London meeting to survey available observations before deciding on new
observatories (which will need to be coordinated with existing ones).
A.
Jayaraman (S. Asia)
Dr.
Jayaraman’s presentation focused on existing and proposed sites in India. He
indicated that during INDOEX most of the surface observations were made in
peninsular India. Stations currently available and proposed in India were divided
in four groups depending on the type of measurements being carried out: a)
LIDAR measurements (Mount Abu, Ahmedabad, Pune, Gadanki, Trivandrum); b) AOD
measurements (Delhi, Ahmedabad, Pune, Hyderabad, Vishakaptnam, Mysore,
Trivandrum, Kanpur); c) Aerosol Chemistry measurements (Delhi, Ahmedabad,
Bombay, Kolkata, Trivandrum); d) Trace Gases and Ozone measurements (Delhi,
Ahmedabad, Pune, Trivandrum). Discussion on new proposed sites in Darjeeling
(NPL), Ahmedabad / Mount Abu (PRL), Port Blair (ISRO, NPL), and Hanimaadho
(C4), and the availability of ships of opportunities (e.g., R/V Sagar Kanya)
was also presented.
H.
Rodhe (S. Asia)
For
this presentation stations were divided in three groups, namely GAW background
stations (solar radiation and gas-phase measurements), GAW regional stations
(rural sites), and RAPIDC rural stations (emphasis on precipitation and aerosol
chemistry). Dr. Rodhe indicated that currently there are no aerosol chemistry
measurements available for the background stations. Potential interesting rural
site stations (e.g., KO, NA, JO, MC, MO, PB) were discussed. Other issues
highlighted by Dr. Rodhe were: a) the importance of including precipitation
chemistry in planned future observations; b) necessary research on soot cycle
(lack of information on this issue); c) relevance of source regions studies
(e.g., northern India, inland central China).
Z.
Li (E. Asia)
Dr.
Li described the status of current observation programs in China, indicating
that they rely mostly on the Solar Radiation Network. Also, he highlighted the
utility of the AERONET network on determining aerosol properties and the
existing gap in the network in regions of East China. Discussion on the
possibility of selecting a site near Beijing for the ABC Project was presented
as well.
H.
Akimoto (E. Asia)
Dr.
Akimoto presented information on the ground stations for APEX and ACE-Asia and
discussed relevant issues concerning criteria for observatory locations
selection (e.g., possibility of selecting stations at high altitudes for clean background
information, effect of local and regional influences on sites, etc.). He
indicated that stations like the ones proposed near Beijing and Seoul can be
affected by local sources, therefore making them ideal for health effects and
source studies, but not suited for studies of the regional impact of
anthropogenic pollution. The existence of un-manned stations for greenhouse
gases and the logistic difficulties of carrying out aerosol chemistry measurements
at these sites were also some of the issues raised in this presentation. Dr.
Carmichael indicated that sites at high altitude (e.g., Rishiri) would be
needed for studies focusing on the interaction of dust with anthropogenic
pollution and dust transport.
K.
Perry (E. Asia)
In this
presentation results from the ACE-Asia Campaign were introduced. The potential for the Hefei site as an aerosol
chemistry site for the ABC Project was discussed. The importance of sites at
high elevations for the study of aerosol transport was also highlighted.
R.
Weiss (AGAGE)
Dr.
Weiss described the main features of the AGAGE network and the collaborations
with NOAA-CMDL, NIES, and SOGE. He described the objectives of the program,
which concentrates on semi-permanent gases and anthropogenic halocarbons (i.e.,
trace-gases measurements). Observations from Mace-Head (Ireland) were shown as
an example of ways in which pollution from Europe has been studied (and ways in
which observations could be designed to study pollution from Asia). Results
from two ground-based monitoring stations in Hateruma Island and Cape Ochi-Ishi
(www-cger2.nies.go.jp) were presented as well. Dr. Ramanthan indicated that the
station in Cape Ochi-Ishi (located in the northern part of Japan) could constitute
an ideal location for studying dust transport.
P-Y.
Whung (S.E. Asia)
Dr.
Whung first clarified some issues concerning the difference between baseline
stations and background stations. Information was shared on the fact that 20
monitoring stations in Mongolia were going to be funded in the near future. The
relevance of Quality Control and Quality Assurance during the operation of the
ABC Project was discussed.
H.
Maring (NASA Network)
Dr.
Maring described the AERONET and MPLNET networks together with their primary
goals and objectives (i.e., primary goal: satellite validation; secondary
purpose: climatological database). Also, he indicated that very few MPLNET
sites are currently in operation.
K.R.
Kim (Project Korean ABC)
Dr.
Kim briefly described the main goals and ideas of the Project Korean ABC
(K-ABC), also indicating proposed and operational sampling sites in Jeju,
Ieodo, Kwangju, Seoul, Tae-An (Anmyondo), and Mt. Baekdu (~ 2800m). Information
on research stations in Jeju Island, namely Kosan, Hallim, and Seoguipo, was
presented. The Korean Program SEES BK21
was discussed in some detail. This program counts with a funding of
approximately U$S 2 M per year (with U$S 339,000 per year being directed for
student training abroad, and U$S 80,000 per year for international
cooperation).
Y.
J. Kim (Project Korean ABC)
Dr.
Kim summarized results from measurements carried out during the intensive
operation period of the ACE-Asia field campaign, with particular emphasis
placed on the measurements from two locations: Kwangju and Jeju. He also highlighted
the presence of associations between dust and soot on observed aerosols, and
the consequent effect on the single scattering albedo.
Chair: V. Ramanathan
Rapporteur: G. Roberts
G.
Carmichael report biomass burning is most important for latitudes less than 30
degrees north and up to 3 km in the boundary layer.
NOx
limited to the south (S.E. Asia) and NMHC limited to the north (mainland China)
Aerosol
loading from 2 to 4 km over India as shown by lidar observations
Eastern
Asia is source of fine aerosol loading
High
AOD over central China with plume extending east over Japan and Hong Kong
Black
Carbon highest over Nepal, Southern India and China
Primary
Soil Dust emissions from Gobi, Dun Huang and Takbimalu(?) deserts
April
à increasing dust storm trends in China
Largest
aerosol forcing in Central China
Decline
in direct solar radiation over 20-30 years by
1-2 W m-2
Not
sufficient aeronet sites in China
Major
dust outflow in N. Japan
Long-range
transport to Hawaii, Aleutian Islands and N.W. U.S.
Major
questions to be identified by aerosol working group
i.
Ability of nations to evaluate models
ii.
Estimate aerosol forcings
iii.
Model Evaluation
1. Models used to predict
climate changes
2. Feed models with emissions
inventories – stress importance of characterizing sources
3. Source characterization –
upstream effects and evolution of aerosols
iv.
Gradients to couple satellite observations with in-situ measurements
i.
Climate / weather – most human influence in coastal regions
1. how does radiative forcing
change surface and top of atmosphere
2. precipitation –
monsoon.hydrological cycle – efficiency on cloud impact and cloud formation
3. feedback of aerosols on
climate – boundary layer thickness
4. to get information on
relevance of surface measurements
5. individual sites to look at
trends – make clear individual responsibility of observatories
ii.
Agriculture – ozone (managed to unmanaged ecosystems)
1. meteorological parameters
2. radiation budget & ozone
iii.
Health – fine particles – biodiversity and direct impact on ecosystems
1. need to study health effects
in cities – regional influences – choice of sites will influence measurements
and interpretation
Stress long term, continuous
measurements to obtain enough information on climate change.
Absolute calibration and
trends
Share data immediately
Archival and sharing data an
important part of ABC
Data documented and
centralized via protocol
Suggested to reverse method
of study à to provide impact study
first
Use first phase to plan
second phase (3-5 years)
Select sites for chemical
diversity – pollution in southern Asia and dust in the north
Capture meteorological
diversity
Site on border of Mongolia
and China – concern on the accessibility of the data if in Mongolia
20 sites to be established
in Mongolia – not know what measurements will be done – suggestion of using the
ABC project to help guide the development of this project.
Suggestions to put site
downwind of city to look at the evolution of aerosol
Use existing sites where
possible
Fund 6-8 observatories must
rely on other institutions to provide data for ABC.
Primary
sites – to exploit regional differences
Measurements
of aerosol to focus on chemical and meteorological diversity
Use
one site for calibration and training – either Maldives or Hateruma
Or
training the PI at site
Chose
sites with meteorological sondes available
More
intense process study with ship and aircraft campaign
-
how does the aerosol get up to 3 km
-
biomass burning / fossil fuel emissions??
Policy
control, standards, and calibrations
Before
choosing sites use inverse model to select surface sites
Chair.
P. Crutzen
Rapporteur: R. von Glasow
The
main discussion topics were the species to be sampled, the required
instrumentation and possible sites.
Gases:
Minimum
set of O3 and CO with short time resolution needed. Also desired for
other gases such as HNO3, NO2, SO2, NH3,
low molecular weight organics (C5 – C9). However, all these gases except for CO
can be measured with inexpensive passive samplers that provide time integrated
concentrations of these species. Passive samplers have been used successfully
for some years.
Additional
gases that would be helpful but would require more elaborate equipment are
radon and acetonitrile. Acetronitrile is
a specific tracer for biomass burning and can be measured online with –
expensive – PTR-MS or offline with GC/MS if it is stable in canisters. Rn222
is a tracer for continental emissions.
Precipitation:
The
analysis of precipitation should include the major ions SO42-,
NO3-, NH4+, Cl- and
carbonaceous aerosol esp. soot.
Standards/calibration:
The
following groups should be contacted for this task: precipitation – Galloway,
passive samplers – group of Martin Ferm, Swedish Environmental research
Institute. He pioneered the use of the passive sampler probes and has a lot of
experience with the analysis and quality control. He is willing to participate
in ABC. Contacts for quality control procedures should be developed with the
Global Atmosphere Watch (GAW/WMO).
Sites:
Sites
both within the source region of the Asian Brown Cloud as well as on its edge
to measure the integrated effects would be needed. Vertically resolved
information would be very helpful. This can be achieved with the help of sites
at different altitudes (one in the boundary layer, another in the free
troposphere), tethered balloons, lidar (costly!) or small aircraft. Russell
Schnell mentioned that NOAA would provide funds for the deployment of regular
vertical soundings with small aircraft, i.e. the costs for the payload and the
analyses without the costs for the flight hours, which are expected to be
modest if small aircraft are used (about $100/hour).
A
tentative list of sites was proposed:
(END)