OPERATIONAL ATMOSPHERIC CHEMISTRY MONITORING MISSIONS

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OPERATIONAL ATMOSPHERIC CHEMISTRY MONITORING
MISSIONSCAPACITY ESA contract no.
17237/03/NL/GS

• GEOPHYSICAL
• DATA REQUIREMENTS
• Michiel van Weele, KNMI
• Final presentation June 2, 2005

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Overview Data Requirements

• Objectives and Strategy to Geophysical Data
  Requirements
• Relations to IGACO and other available
  requirements
• Sampling and coverage atmospheric domains
• Spatial resolution and revisit time
• Uncertainty
• Measurement Strategy Ozone Layer and UV
• Measurement Strategy Air Quality
• Measurement Strategy Climate
• Geophysical Data Requirements Tables
• Summary

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Objectives

• User Requirements per Theme
• Ozone Layer and Surface UV Radiation
• Air Quality
• Climate
• and per User Type / Application
• Protocol Monitoring
• Near-real time data use
• Assessment
• Objectives
• Compile the user requirements per theme / user
  category and interpret in terms of a required set
  of observables per atmospheric domain
• Define a measurement strategy for the optimal
  combination of satellite observations,
  ground-based / in-situ observations and use of
  models

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Strategy to Data Requirements

• Specify for each parameter the (threshold)
  resolution and revisit time requirements per
  atmospheric domain and on the basis of the
  observed spatial and temporal variability
• Define a measurement strategy the different role
  of satellite data, ground-based networks and
  atmospheric models for each theme/user type
  combination
• Investigate the role of data assimilation for
  uncertainty requirements, also in relation with
  the established resolution and revisit time
  requirements and sampling/coverage
• Define the auxiliary data requirements for the
  applications.
• Examine and try to understand differences with
  tabulated data requirements such as IGACO,
  GMES-GATO/BICEPS, ESA studies (ACECHEM, GeoTrope,
  Kyoto), Eumetsat paper on Nowcasting, and MTG
  requirements

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Relations to IGACO and other Requirements

• IGACO data requirements have not been specified
  per theme/user type. Instead, distinction has
  been made in a group-1 (existing systems) and
  group-2 (next generation systems) set of
  observables
• IGACO has four themes, CAPACITY only three. The
  fourth theme of IGACO is the oxidising capacity,
  which in Capacity has been integrated in the
  assessment of the three other themes
• IGACO requirements are given on a per species and
  atmospheric domain basis, but the rationale
  behind each of the quantitative requirements has
  not been detailed in the IGACO report.
• ACECHEM and GeoTrope are compilations of data
  requirements for research missions and exceed
  operational data requirements
• Eumetsat Nowcasting position paper only contains
  requirements for lt12 hours ahead
• MTG requirements focus on the geostationary,
  non-global perspective

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Sampling and Coverage Requirements

• The themes (Ozone Layer, Air Quality and Climate)
  are all of a global nature. The target
  requirement for satellite observations is to get
  as close as possible to global coverage with
  near-contiguous sampling.
• Ground-based networks should be globally
  representative.
• For Air Quality additional focus is on the local,
  regional to continental scale in Europe.
  Threshold coverage for satellite data and surface
  networks contributing to Air Quality is Europe,
  including Turkey and Europes coastal waters as
  well as the closest parts of the North-Atlantic.
• The aim of each component to an integrated system
  should be to maximize its contribution, the
  number of independent observations mainly being
  limited by any of the other data requirements on,
  e.g., uncertainty, resolution and revisit time.
• The integrated system will allow data gaps in
  space and time, however only up to a certain
  extent. This will depend on the application.

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• Atmospheric domains

 
Tropics Eq. 30
Mid-latitudes 30 60
Polar region 60 Pole
80 km
USM
USM
USM
35 km
MS
MS
MS
20 km
LS
LS
LS
16 km
TTL
LS
LS
12 km
FTUT
FT,UT
FTUTLS
6 km
FT
FT
FT
2 km
PBL
PBL
PBL
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Uncertainty

• The (assumed) uncertainty mainly determines the
  potential impact of observations in assimilation
  systems. These requirements are most quantitative
  and are leading.
• The uncertainty requirement contains a random
  component and a systematic component. The latter
  component can only be established by long-term
  validation with independent measurements.
• For ground-based and in-situ observations a
  representation error will contribute
  significantly to the overall uncertainty.
  Satellite observations suffer less from this
  error as long as the resolution is more or less
  comparable to the model grid size.
• Large numbers of independent observations from
  prolonged data sets with stable retrievals and
  limited instrumental drift will help to better
  characterize random and systematic components
  (gt mission lifetime)
• Spatio-temporal variations in (current) model
  uncertainties have not been taken into account.
  Model uncertainties are often related to
  intermittent processes and unpredictable events,
  which are often difficult to assign to certain
  locations and time periods and can not easily be
  used to relax requirements.

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Spatial Resolution and Revisit Time

• Typically the resolution and revisit time
  requirements are determined by the known
  variability of the observable in space and time
  in the different atmospheric domains. Ultimate
  threshold is to observe some of the
  variability.
• The horizontal resolution should be typically a
  factor 2-3 smaller than the error correlation
  length (ECL) used in the assimilation of the
  observable. The error correlation length is
  typically a function of altitude and determined
  by physical processes. The ECL decreases from
  several 100 kms in the middle stratosphere to
  tens of kilometers in the troposphere and even
  smaller in the PBL.
• Vertical resolution requirements are related to
  the observed vertical gradients in the
  atmosphere. Requirements are most stringent in
  the UTLS and PBL and much less in the free
  troposphere and middle stratosphere and
  mesosphere.
• In principle, the revisit time requirements can
  also be based on required update frequencies from
  assimilation studies on anomaly correlations.
  These correlations however mainly depend on the
  predictability of the meteorology. Revisit time
  requirements are most stringent in the PBL.

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Data Requirements per Theme and User
CategoryTheme A Ozone Layer and Surface UV
Radiation A1. Protocol Monitoring A2. Near-real
time data use A3. AssessmentTheme B Air
Quality B1. Protocol Monitoring B2. Near-real
time data use B3. AssessmentTheme C
Climate C1. Protocol Monitoring C2. Near-real
time data use C3. Assessment
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Measurement Strategy A1O3/UV Protocol Monitoring

• Role of Satellite measurements
• Monitoring of the global total ozone spatial
  distribution (lt3 uncertainty for individual
  measurements)
• Contribution to the monitoring of surface UV
  radiation by provision of information on total
  ozone, solar irradiance, surface albedo, and
  aerosol optical depth and absorption
• Role of Surface network
• Trends in concentrations of regulated ozone
  depleting substances (ODS)
• Detection of ODS emissions and their trends
• Trend in Surface UV and the attribution of UV
  changes to ozone layer changes
• Validation of the satellite data
• Weekly surface/column observations (O3, ODS) by
  representative surface networks
• Auxiliary data
• Meteorology from NWP centers including surface
  data (dynamics, clouds, snow cover)

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Measurement Strategy A2O3/UV Near-real time data
use

• Role of Satellite Measurements
• Forecasting of the Ozone layer and surface UV
  Feed polar ozone reports
• Better representation of stratospheric transport,
  chemistry and radiation in NWP to improve (medium
  range) weather forecasts and stratospheric
  near-real time monitoring, also by improving
  retrievals of temperature gt stratospheric
  distribution of major greenhouse gases (CO2, H2O,
  O3, CH4, N2O) and aerosols
• Further tracers (B-D circulation, ST exchange),
  PSCs
• Role of surface network and in-situ operational
  measurements
• NRT validation of the satellite measurements
• Ozone/ radiosondes NRT delivery of O3, H2O, p,
  T, wind
• NRT delivery of (UTLS) aircraft observations of
  O3, H2O, CO, HNO3, HCl
• Auxilary data
• Meteorological forecast from NWP centers
  including surface data (dynamics, clouds,
  sunshine duration, snow cover)

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Measurement Strategy A3O3/UV Assessment

• Role of Satellite measurements
• State of ozone layer and its evolution in time
  role of dynamics, radiation, and chemistry
• Changes in surface UV radiation globally, per
  location
• Distribution and trends in ODS and reservoir
  species
• The role of PSCs and of denitrification
• The role of volcanic eruptions (SO2, aerosol,
  aerosol type)
• Short-lived species can typically be derived from
  long-lived species given that the chemistry is
  sufficiently understood (some exception NO2, ClO
  etc)
• Role of Surface network
• Validation of the satellite measurements
• Surface UV radiation trend monitoring and
  attribution
• Concentration monitoring ODS detection of ODS
  emissions
• Auxiliary data
• meteorology from NWP centers including surface
  data (dynamics, clouds, sunshine duration, snow
  cover)

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O3 / Surface UV Radiation Satellite Data

• Observable User(s) Domain(s)
• O3 A1, A2, A3 Stratosphere, Troposphere
• UV solar spectrum A1, A2, A3 Top-of-Atmosphere
• UV aerosol optical depth A1, A2, A3 Troposphere
• UV aerosol absorption optical depth A1, A2,
  A3 Troposphere
• Spectral UV surface albedo A1, A2, A3 Surface
• H2O A2, A3 Stratosphere
• N2O A2, A3 Stratosphere
• CH4 A2, A3 Stratosphere
• CO2 A2, A3 Stratosphere
• HNO3 A2, A3 Stratosphere
• Volcanic aerosol A2, A3 Stratosphere
• CFC-11 A3 Stratosphere
• CFC-12 A3 Stratosphere
• HCFC-22 A3 Stratosphere
• ClO A3 Stratosphere

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Measurement Strategy B1Air Quality Protocol
Monitoring

• Role of Satellite Measurements
• Interpolation of surface networks in the PBL
• Boundary conditions for regional AQ models and
  tropospheric background (long-range transport)
• Application to inverse modeling of surface
  emissions (aerosols, NO2, SO2, CO, CH2O).
  Formaldehyde is related to VOC emissions
• Role of Surface Networks
• EU Framework Directives (surface concentrations)
• National Emission Ceilings (concentration
  monitoring to derive emissions)
• Gothenburg protocol on ground-level ozone
• Ship emissions (operational ship monitoring
  coastal waters)
• A representative network for surface
  concentrations and emissions in Europe
• Satellite and model validation, also by boundary
  layer profiling (LIDARS, Towers)
• Auxiliary data
• Meteorology from NWP Centers including surface
  data (dynamics, clouds, surface characterization)
• Emission inventories

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Measurement Strategy B2Air Quality Near-real
time data use

• Role of Satellite Measurements
• Interpolation of surface network in PBL
• Plume transport and plume dispersion on local,
  regional, continental and global scale
• Boundary conditions to regional AQ models and
  tropospheric background levels
• Early warnings on hazards and unpredictable
  events
• Role of Surface Networks
• Local Air Quality monitoring of surface levels
• Constraints on satellite-derived aerosol types
  and VOC emissions from HCHO
• NRT ozone sonde data for ozone and relative
  humidity profiles
• CH4 trend monitoring
• Auxiliary data
• Forecast meteorology from NWP centers including
  NRT surface / vegetation data
• Emission inventories

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Measurement Strategy B3Air Quality Assessment

• Role of Satellite Measurements
• Global-scale oxidizing capacity components and
  their evolution in time (O3, CO, H2O, NOx, CH4,
  CH2O, UV, aerosols)
• Long-range transport of pollutants tropospheric
  background levels
• Interpolation of data from surface networks
• input to inverse modeling of surface emissions
  (CO, NOx, SO2, CH2O)
• Isotopes of CO to distinguish between emission
  types
• Role of Surface network
• Assessment of surface concentrations and boundary
  layer pollution over Europe
• Concentration monitoring to derive emissions on
  national levels
• HNO3, N2O5(at night) and org. nitrates reservoir
  species to constrain acid deposition and N budget
• Validation of satellite observations (including
  sondes, lidars, towers)
• Auxilary data
• Meteorology from NWP centers including surface
  characterisation
• Emission inventories

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Air Quality Satellite Data

• Observable User(s) Domain(s)
• O3 B1, B2, B3 PBL/Troposphere
• NO2 B1, B2, B3 PBL/Troposphere
• CO B1, B2, B3 PBL/Troposphere
• SO2 B1, B2, B3 PBL/Troposphere
• CH2O B1, B2, B3 PBL/Troposphere
• Aerosol OD B1, B2, B3 PBL/Troposphere
• Aerosol Type B1, B2, B3 PBL/Troposphere
• H2O B2, B3 PBL/Troposphere
• HNO3 B2, B3 PBL/Troposphere
• N2O5 B2, B3 PBL/Troposphere
• PAN / Org. nitrates B2, B3 PBL/Troposphere
• Surface UV albedo B2, B3 Surface

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Measurement Strategy C1Climate Protocol
Monitoring

• Role of Satellite Measurements
• Concentration monitoring for inverse modeling of
  emissions of CH4, CO2, CO and NO2
• Global concentration distributions of the
  mentioned gases, O3 and aerosols
• Role of Surface network
• Greenhouse gases trend monitoring (CO2, CH4, N2O,
  SF6, CF4, HFCs
• Weekly surface concentrations and total columns
  from a representative network.
• Validation of satellite measurements
• Concentration monitoring for inverse modeling of
  surface emissions of CH4, CO2, CO and NO2
• Tropospheric O3 sondes, lidar and surface data
• Tropospheric aerosol optical depth and aerosol
  absorption optical depth
• Trend monitoring for ozone depleting substances
  ODS with climate forcing (H)CFCs.
• Auxiliary data
• Meteorology from NWP centers including surface
  data
• Emission inventories and estimates on sinks

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Measurement Strategy C2Climate Near-real time
data use

• Role of Satellite Measurements
• For use in assimilation at NWP centers to improve
  on stratospheric elements
• H2O, O3, stratospheric tracers, and information
  on aerosols and cirrus
• Climate monitoring (delivery time weeks
  months)
• Validation of climate and NWP models (present-day
  climate reconstructions)
• Role of Surface network
• NRT validation of satellite observations
• Evolution of long-lived greenhouse gases
• In-situ observations in the PBL of CO2
• NRT delivery of ozone sonde / Lidar data O3,
  H2O
• Auxiliary data
• Forecast meteorology from NWP centers including
  surface data

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Measurement Strategy C3Climate Assessment

• Role of Satellite Measurements
• Assessment radiative forcing and its changes over
  time, including volcanic eruptions and solar
  cycle GHGs, aerosol OD, aerosol absorption, SO2,
  cirrus)
• Assessment of stratospheric H2O budget and H2O
  trend monitoring
• The role of the ozone layer evolution on climate
  change CFCs, Cly, ClO, HNO3
• The role of the oxidizing capacity of the
  troposphere for climate change (CH4, CO, O3, H2O,
  NOx, UV)
• The role of a changing B-D circulation on climate
  change tracers
• Concentration monitoring for inverse modeling of
  GHG precursor emissions
• Role of Surface network
• Validation of satellite observations
• Ozone sonde/LIDAR network for trends in strat.
  profiles of long-lived gases
• Radiosonde/GPS network for H2O and T
• Aerosol network
• UTLS operational aircraft observations of O3,
  H2O, CO, NOx
• Auxiliary data

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Climate Satellite Data

• Observable User(s) Domain(s)
• CH4 C1 PBL, Troposphere
• CO2 C1 PBL, Troposphere
• CO C1 PBL, Troposphere
• NO2 C1 PBL, Troposphere
• O3 C1 PBL, Troposphere
• Aerosol OD C1 PBL, Troposphere
• Aerosol absorption OD C1 PBL, Troposphere
• H2O C2, C3 Troposphere, Stratosphere
• O3 C2, C3 Troposphere, Stratosphere
• CH4 C2, C3 Stratosphere
• CO2 C2, C3 Stratosphere
• N2O C2, C3 Stratosphere
• Aerosol optical properties C2, C3 Stratosphere
• Cirrus optical properties C2, C3 Troposphere
• HNO3 C3 Troposphere, Stratosphere
• NO2 C3 Stratosphere

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Data Requirements Table Format

• A1S
• Ozone Layer Protocol Monitoring Satellite data
• Data product Driver
• Height Range(s)
• Hor. Resolution (target/threshold)
• Vert. Resolution (target/threshold)
• Revisit time (target /threshold)
• Uncertainty (threshold)

Similar Tables for A1-G, A2-S, A2-G, .C3-S,
C3-G (18 Tables in total)
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Summary

• This work has drawn from several earlier
  requirement studies, but it has never been done
  before in such a comprehensive way with focus on
  atmospheric composition and for operational
  applications
• Geophysical Data Requirements have been tabulated
  per theme and within each theme per user type
• Per data product and product type (column,
  profile) resolution, revisit time and uncertainty
  have been tabulated, for each atmospheric domain
• Based on the definition of drivers per
  application a measurement strategy has been
  proposed for satellites, ground-based/in-situ
  data and auxiliary data, including models
• The tables, traceable to the user requirements,
  served as input for the analysis of
  existing/planned missions and networks, and for
  the definition of instrument requirements for new
  mission concepts