Post on 01-Apr-2018
CREATE – Atmosphere
Prof. S. Gerard Jennings(with input from several CREATE partners)
Atmospheric Research GroupEnvironmental Change Institute
Department of Experimental PhysicsNational University of Ireland, Galway
Galway, Ireland
Construction, Use and Delivery of an European Aerosol Data Base : CREATE
Coordinator: National University of Ireland, Galway
NILU, Norway
LSCE, France
Ift, Germany
TNO, Netherlands
University of Helsinki
ECN, Netherlands
Finnish Meteorological Institute
University of Crete
MPI, Germany
PSI, Switzerland
• What are aerosols?
• Aerosols are tiny particles suspended in air.
• Some occur naturally, originating from volcanoes, dust storms, forest and grassland
fires, living vegetation, and sea spray.
• Human activities, such as the burning of fossil fuels and traffic, also generate aerosols.
EU Aerosol Projects under the theme ‘Global Atmosphere Monitoring’ in support of GMES
DAEDALUSDelivery of Aerosol Products for
Assimilation and environmental Use
CREATEConstruction, use and Delivery of a
European Aerosol database
Present Status of Aerosols
Aerosol discipline - in contrast to the situation some 10 –15 years ago – is receiving increasing attention from the EU, and national bodies, because of increased awareness of its climate, air quality and health effects
Progress is being made in our knowledge of aerosol properties and processes of their formation, transformation and fate
Unlike gases, aerosols have relatively short lifetimes, are highly variable both spatially and temporally
Need for : more measuring stations and models to predict levels in regions not covered
Present Status of Aerosols (continued)
Nevertheless, we are still at an early stage in our knowledge ofcomposition of aerosols – for example: organic component, size fractionated chemical composition
Disparate non-compatible collections of aerosol parameters are held by a range of dispersed sources:Field sites, Networks, Institutes, by individual Groups and in different formats
Procedures and techniques for measurement of aerosols also vary – no standardized procedures in place
GMES Atmosphere : CREATE & DAEDALUS Projects
Needs and Gaps:
a) Need for spatial and temporal monitoring of aerosols
b) Need for common protocol of data submission
c) Need for long term sustained support for monitoring
d) Lidar Network needs further technical support
g) Need for quality assurance of data
h) Need for database for user needs
CREATEConstruction, use and delivery of a European Database
Report on aerosol measurement techniques and harmonization of calibration procedures
Recommend list of European monitoring sites
Delivery of aerosol knowledge/training to data providers and data users Examples: Tutorials & Measurement/Analyses Workshops; Field visits
Catalogue of maps of aerosol levels over Europe from measured data and model outputs
Provision of an European Aerosol Database
Main Outputs and Products:
• Aerosol Database to EMEP/ WMO GAW Standard
• Retrieval of Aerosol parameters from Satellite systems
• Mapping of Aerosol Data with Modelled Aerosol fields
• Representativeness of surface and vertical profile data
• Harmonised Aerosol Measured Procedures
• Training and Skill development of Atmospheric Scientists and Field Station Operators.
Present Observational Situation1. Existing Networks:
EMEP: The Cooperative Programme for Monitoring and Evaluation of Air Pollutants in Europe (EMEP) is a regional policy driven monitoring programme under the Convention on Long Range Transboundary Air Pollution (LRTAP).
In 2002:i) 14 countries in Europe were measuring PM10 (particulate matter) below 10 micrometresii) 6 countries are measuring PM2.5iii) No PM1 measurements in Europe
Present Observational Situation (continued)World Meteorological Organisation (WMO) Global Atmosphere
Watch (GAW):
Supported by some 80 WMO countries with 22 Global stations and some 300 Regional stations.
http://www.empa.ch/gaw/gawsis/ (GAW station information)
European Air Quality Monitoring Network (EuroAirnet)developed by the European Environmental Agency (EEA) and the European countries. Data from EuroAirnet is reported to AIRBASE , managed by the European Topic Centre on Air Quality and Climate Change.
In 2000: PM10 data from 425 stations in 17 countries were in thedatabase.
In 2001: PM10 data from 928 stations from 24 countries.
Objective of the Global Atmosphere Watch Aerosol
Programme :
To determine the spatio-temporal distribution of aerosol properties related to climate forcing and air quality at up to multi-decadal time scales
Global Atmosphere Watch (Aerosol) consists of :
1) 22 Global Stations representing main aerosol types:
Background Polluted Continental
Marine Arctic
Mineral Dust Biomass burning
Free Troposphere
2) Some 300 Regional Stations
Recommended Aerosol parameters for Regional Stations:
Aerosol mass concentration - 2 size fractions
Aerosol chemical composition – 2 size fractions
Aerosol Light scattering coefficient
Aerosol Absorption coefficient
Regional site measurements:Aerosol mass concentration - 2 size fractionsAerosol chemical composition – 2 size fractions Light scattering coefficient at a single wavelengthAbsorption coefficient at a single wavelength
Together with:Total aerosol number concentrationAerosol light scattering and hemispheric backscatter coefficient at a number of wavelengthsAbsorption coefficient at a number of wavelengthsCloud condensation nucleus (CCN) concentrationDiffuse, global and direct solar radiationAdditional parameters
Recommended Aerosol parameters for GAW Global Stations:
Additional Aerosol parameters for Global Stations:
Aerosol size distribution
Detailed size fractionated chemical composition
Dependence of aerosol properties on Relative Humidity
CCN concentration at a range of supersaturation
Vertical distribution of aerosol properties
WMO World Calibration Centre for Aerosols
1. World Calibration Centre for Aerosol Physical Instrumentation is at the Institute for TroposphericResearch (IfT), Leipzig
• Calibration Workshops for specific aerosol physical instrumentation
• Lecture courses in aerosol physics, aerosol instrumentation and atmospheric aerosols
Users: Field station operatorsNew aerosol researchers
Contact: Ali Wiedensohler (ali@tropos.de)
WMO World Calibration Centre for Aerosols2. World Optical Depth Research and Calibration
Centre (WORCC) is operated by the Physikalisch –Meteorologisches Observatorium Davos , World Radiation Centre (PMOD/WRC) at Davos, Switzerland ( funded by Swiss GAW)
• Provides Precision Filter Radiometers operating at 4 wavelengths (368, 412, 500 and 862 nm), permitting measurement of aerosol optical depth
• Installed initially at Izania, Mace Head, Mauna Loa
• Regular calibration with travelling standard
Contact: Christoph Wehrli (chwehrli@pmodwrc.ch)
WMO World Data Centre for Aerosols (WDCA)
The World Data Centre for Aerosols (http://ies.jrc.cec.eu.int/wdca/) is operated by the Institute for Environment and Sustainability of the EU Joint Research Centre, Ispra, Italy.
• It provides public access to the aerosol observations made within GAW
Contact: Julian Wilson (julian.wilson@jrc.it)
Challenges in measurement of Atmospheric Aerosol
• Gravimetric measurement of volatile aerosol: losses
• Organic aerosol fraction is uncertain
• Black carbon fraction: uncertainty remains
• Water can have considerable effect on aerosol mass –due to evaporation or condensation on the sample
• Mass closure remains challenging
• Complete characterisation over entire spectrum is rare
• Relatively little vertical information is available
Contribution of nitrate to "PM
10" at given sites for situations with
high aerosol levels
0%
10%
20%
30%
Melpitz 96-99 (G)
Ispra (I)
Zuerich (CH)
Basel (CH)
Gent (B)
Bologna (I)
Barcelona (E)
Bern (CH)
NO3 contributribution to PM10
Mass concentration (µg m-3) of (ammonium) nitrate as a function of size, measured on top of a meteorological tower in central Netherlands. The complete histogram bar
represents the total mass concentration of nitrate.
0
5
10
15
20
25
23-0
4-20
01 0
6:46
:45
23-0
4-20
01 1
5:46
:21
23-0
4-20
01 2
3:46
:21
24-0
4-20
01 0
7:46
:21
24-0
4-20
01 1
5:46
:21
24-0
4-20
01 2
3:46
:21
u g/m
3
>3.2
1<>3.2
0.32<>1
0<>0.32
Indoor vs. ambient conditions
500
1000
1500
dN/d
log(
D)
[cm
-3]
1 hour averages (28/3/2000 from 3.30 until 4.30)
20
40
60
80
dS/d
log(
D)
[ µµ µµm
2 cm
-3]
ambient measurements (RH=69%) dry measurements (RH<10%) dry measurements, corrected for RH=69%)
101
102
103
0
2
4
6
8
particle diameter D [nm]
dV/d
log(
D)
[ µµ µµm
3 cm
-3]
ambient measurements (RH=69%) dry measurements (RH<10%) dry measurements, corrected for RH=69%)
Nessler et al.,in press (2003)
Lidar
• Only tool to provide vertically resolved aerosol
• EARLINET (EU Project) and German Aerosol Lidar Network
Provide the 1st Lidar Data set at some 20 sites in Europe
• Raman Lidar provides real quantitative data
• Development of sophisticated systems at ‘supersites’
• Joint use of Lidar, sunphotometers and satellite systems
• Recommend continuation of vertical profiling of the atmosphere
• Support required to continue with Lidar network
Clean cloud
Polluted cloud
More CCNSmaller CCN
Drizzle
INDIRECT AEROSOL EFFECT
European Mediterranean Pollution:
• Reduces air quality in the Summer
• Increasing aerosol levels causes increased surface cooling due to enhanced backscattered radiation
• This reduces evaporation from the ocean surface,
which in turn reduces precipitation
• Climate model indeed predicts 10-50% reduction in
precipitation in Mediterranean region (Lelieveld et al, 2002).
Lelieveld et al., Science, 2002
4D assessment of aerosol data by means of aerosol transport models
Status
Michael Schulz / Lab. des Sciences du Climat et de l'EnvironnementCEA/CNRS, Gif -sur-Yvette, France
• Several complex aerosol models are recently developed=> in Europe: EURAD, ECHAM, LMDZ, EMEP, LOTOS +…
• Forecasting of PM10 is available (e.g. EURAD)
• Aerosol model intercomparisons are started⇒non funded projects: AEROCOM, GLOREAM
• Validation by comparison to EMEP type data, satellite observations of optical depth
• Assimilation procedures under development
Aerosol Optical DepthLMDZ INCA model
4D assessment of aerosol data by means of aerosol transport models
• Reduction of uncertainty on aerosol radiative forcing
• Regional emission inventory verification
• Future aerosol load scenarios
• Impact of aerosols on weather forecast
• Short-term prediction of PM10, PM2.5 and PM1(regional smog abatement and traffic perturbation)
• Eutrophification and Pollution assessments
Current Needsaddressed by global/regional aerosol models
4D assessment of aerosol data by means of aerosol transport models
Gaps
• Partially fundamental understanding of aerosol formation, transformation, removal, hygroscopicity, optical properties
=> Model development still needed!!!
• Refined emission inventories (present/future)
• Model quality control standards and tools
• CPU-power to run interactive chemistry and aerosol models on high spatial resolutions
• Access to Qualified Observational Data formultiple regions from longterm observing facilities
Some concluding thoughts and conclusions
• Gaps between available aerosol data products and users requirements need bridging – a thrust of GMES
• Need for improved linkages between more research oriented programmes and Regulatory Monitoring Networks – CREATE and DAEDALUS Projects will help enable this, through involvement of EMEP and WMO GAW for example
• Need for improved coordination between observational stations
• Improvement of existing stations and networks and development of new ones (Presently: decreasing observational capacity)
• Standardization of data
• Improve access to data and data products
• Validation of satellite derived products through ground truth and vertical data
Some further thoughts and conclusions
• Relatively few advances have been made with new aerosol instrumentation
• Need for: Fast response aerosol chemical composition techniques
• In situ aerosol microphysical measurements – most instruments measure dryand not ambient aerosol
• Need for multi- disciplinary approaches in tackling aerosols – coupled with meteorological and model inputs
• need to understand better: effects of aerosols on health and climate (research driven projects)