Future Atmospheric Missions: Adding to the

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Future Atmospheric MissionsAdding to the A
TrainJim Gleason
NPP
Acknowledgements Graeme Stephens, Bruce
Wielicki, Chip Trepte, Dave Crisp, Charles
Miller, Glory Team
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The Afternoon Constellation
NPP
VIIRS - Clouds Aerosols CrIS/ATMS- Temperature
and H2O Sounding OMPS - Ozone
130 PM
130 PM
115 PM
Glory
Cloudsat
OCO
CALIPSO
Aqua
PARASOL
OCO - CO2 column
CALIPSO- Aerosol and cloud heights Cloudsat -
cloud droplets PARASOL - aerosol and cloud
polarization OCO - CO2
MODIS/ CERES IR Properties of Clouds AIRS
Temperature and H2O Sounding
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NPP is not in a control box
CALIPSO Control Box
Aqua Cloudsat CALIPSO PARASOL Aura
Cloudsat will orbitCALIPSO, both loosely
following Aqua
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CALIPSO(formerly Picasso-CENA)
Cloud-Aerosol Lidar and Infrared Pathfinder
Satellite Observation
IIR
20
km
10
Laser
WFC
0
Distance
LITE measurements over convection

• 2-wavelength (532 and 1064 nm)
  polarization-sensitive LIDAR that provides 30 m
  vertical resolution profiles of aerosols and
  clouds.
• Imaging infrared radiometer (IIR) that provides
  calibrated infrared radiances at 8.7 µ, 10.5 µ
  and 12 µ. These wavelengths are optimized for
  combined IIR/lidar retrievals of cirrus particle
  size.
• High-resolution wide field camera (WFC) that
  acquires high spatial resolution imagery for
  meteorological context (620 to 670 nm).

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Cloudsat

• 94 GHz Cloud Profiling Radar (CPR)
• Nadir-viewing
• 500 m vertical resolution
• 1.2 km cross-track, 3.5 km along track
• Sensitivity -30 to -36 dBZ

Data Products

• Radar reflectivity
• Visible and near-IR radiances
• Cloud base and top heights
• Optical depth
• Atmospheric heating rates
• Cloud water content
• Cloud ice content
• Cloud particle size
• Precipitation Occurrence

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NPOESS Preparatory Project NPP

• Sun - synchronous, polar
• Altitude - 824 km nominal
• Inclination - 98 degrees
• Ascending node - 1030 a.m.
• Launched April 2008

Instruments

• Cross Track Infrared Sounder (CrIS)
• Advanced Technology Microwave Sounder (ATMS)
• Visible Infrared Imaging Spectrometer (VIIRS)
• Ozone Mapping and Profiler Suite (OMPS)

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Ozone Mapping Profiler Suite

• Status
• Brass Board Main Electronics Box complete
• Flight Unit 1 Assembly underway

• Description
• Purpose Monitors the total column and vertical
  profile of ozone
• Predecessor Instruments
  TOMS, SBUV,
  GOME, OSIRIS, SCIAMACHY
• Approach Nadir
  and limb push broom
  CCD spectrometers
• Swath width 2600 km

Algorithm Status Using TOMS/SBUV heritage
approaches for Nadir Instruments Limb profile
still in development using new space-based limb
observation data
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OMPS Scanning Track
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Orbiting Carbon Observatory - OCO
OCO is an ESSP Mission LRD 2008
Instruments- 3 Grating Spectrometers O2 - A Band
at 0.76µ CO2 at 1.58, 2.06 µ Swath 10 pixels,
1x1.5 km
CO2 Simulation Map

• Make global, space-based observations of the
  column integrated CO2
• Provide independent data validation approaches
  to ensure high accuracy (1 ppm, 0.3)
• Combine satellite data with ground-based
  measurements to characterize CO2 sources and
  sinks on regional scales on monthly to
  interannual time scales

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The Orbiting Carbon Observatory (OCO)
OCO will acquire the space-based data needed to
identify CO2 sources and sinks and quantify their
variability over the seasonal cycle

• Approach
• Collect spatially resolved, high resolution
  spectroscopic observations of CO2 and O2
  absorption in reflected sunlight
• Use these data to resolve spatial and temporal
  variations in the column averaged CO2 dry air
  mole fraction, XCO2 over the sunlit hemisphere
• Employ independent calibration and validation
  approaches to produce XCO2 estimates with random
  errors and biases no larger than 1 - 2 ppm (0.3 -
  0.5) on regional scales at monthly intervals

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Making Precise CO2 Measurements from Space

• High resolution spectra of reflected sunlight in
  near IR CO2 and O2 bands are combined to retrieve
  the column average CO2 dry air mole fraction,
  XCO2
• 1.61 ?m CO2 bands Column CO2 with maximum
  sensitivity near the surface
• O2 A-band and 2.06 ?m CO2 band
• Surface pressure, albedo, atmospheric
  temperature, water vapor, clouds, aerosols
• Why high spectral resolution?
• Enhances sensitivity, minimizes biases

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OCO Observing Strategy

• Nadir Observations tracks local nadir
• Small footprint (lt 3 km2) isolates cloud-free
  scenes and reduces biases from spatial
  inhomogeneities over land
• Low Signal/Noise over dark ocean
• Glint Observations views glint spot
• Improves Signal/Noise over oceans
• More interference from clouds
• Target Observations
• Tracks a stationary surface calibration site to
  collect large numbers of soundings
• Data acquisition schedule
• alternate between Nadir and Glint on 16-day
  intervals
• Acquire 1 Target observation each day

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Calibration/Validation ProgramAssures
Measurement Accuracy

• Calibration
• Pre Launch
• Instrument Subsystem
• Observatory-level
• On-Orbit
• Routine (Solar, Limb, Dark, Lamp)
• Special (Stellar, Solar Doppler)
• Vicarious
• Validation
• Laboratory spectroscopy
• Spectral line databases for CO2, O2
• Ground-based in-situ measurements
• NOAA ESRL Flask/Tower Network
• Wofsy (Harvard), Ciais (CNRS Aerocarb)
• Solar-looking FTS measurements of XCO2
• Measure same bands as flight instrument

Routine Calibration
WLEF Tower
WLEF FTIR
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Glory mission provides timely key data for
climate change research

• The Glory Mission Objectives are to
• Quantify the role of aerosols as natural and
  anthropogenic agents of climate change by flying
  APS
• Continue measuring the total solar irradiance to
  determine its direct and indirect effects on
  climate by flying TIM

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Existing aerosol retrievals from space are
inadequate
Glory APS strategy fully exploit the
information content of the reflected sunlight
Classification of passive remote sensing
techniques by
1. Spectral range 2. Scattering geometry range 3.
Number of Stokes parameters

• Hierarchy of existing/planned
• instruments
• AVHRR ? MODIS, MISR, VIIRS ? Glory APS
• Glory APS will be a bridge to NPOESS era
  measurements.

• The measurement approach developed for the Glory
  mission is to use
• multi-angle multi-spectral polarimetric
  measurements because
• Polarization is a relative measurement that can
  be made extremely accurately.
• Polarimetric measurements can be accurately and
  stably calibrated on orbit.
• The variation of polarization with scattering
  angle and wavelength allows aerosol particle
  size, refractive index and shape to be
  determined.
• Appropriate analysis tools are available.

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Glory APS summary
Type Passive multi-angle photopolarimeter Fore-op
tic Rotating polarization-compensated mirror
assembly scanning along orbit-track 50.5 to
63 (fore-to-aft) from nadir Aft-optic 6
bore-sighted optical assemblies, each with a
Wollaston prism providing polarization
separation, beamsplitters bandpass filters
producing spectral separation, and paired
detectors sensing orthogonal polarizations Directi
onality 250 views of a scene Approx.
dimensions 60 x 58 x 47 cm Mass/power/data rate
53 kg / 36 W / 120 kbps Spectral range 4122250
nm Measurement specifics 3 visible (412, 443,
555 nm), 3 near-IR (672, 865, 910 nm), and 3
short-wave IR (1378, 1610, 2250 nm) bands three
Stokes parameters (I, Q, and U) Ground
resolution at nadir 6 km SNR requirements 235
(channels 1 5, 8, and 9), 94 (channel 6), and
141 (channel 7) Polarization accuracy 0.0015 at
P 0.2, 0.002 at P 0.5 Repeat cycle 16 days
APS angular scanning
APS spectral channels
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Summary of the A Train

• The Formation
• Aqua (130 PM )and Aura (138 PM)) must maintain
  ground track on the WRS (20 km) using frequent
  burns (once every 3 months)
• Cloudsat and CALIPSO 20 seconds (140 km) behind
  Aqua within a control box 40 seconds wide. Near
  end of mission, CALIPSO drifts (left) across
  MODIS swath.
• PARASOL is roughly lined up Aqua about 3 minutes
  behind
• Aura is 15 minutes behind Aqua (crossing time is
  138 PM)
• OCO is 15 minutes ahead of Aqua (115)
• NPP same crossing time, higher orbit
• The Science
• Unprecedented cloud science
• Unprecedented climate/aerosol/chemistry science
• Correlative measurements
• Challenges
• Variety of vertical and horizontal resolutions
  which will be challenging to match
• Community is not used to using multi-instrument
  systems

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New Mission Planning

• Air Quality Mission Workshop
• Boulder, CO February 2006
• Satellite observations as crucial for the future
  of AQ management
• Air quality characterization for retrospective
  assessments and
• forecasting to support air program
  management and public health advisories
• 2. Quantification of emissions of ozone and
  aerosol precursors
• 3. Long-range transport of pollutants extending
  from regional to global scales
• 4. Large puff releases from environmental
  disasters.

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y_Remote_Sensing/index.shtml
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Air Quality Mission Workshop Report to National
Research Council Decadal Survey

• Measurement Requirements
• Species measured Tropospheric ozone, CO, NO2,
  HCHO, SO2, and aerosols
• Horizontal resolution and coverage better than
  10 km (preferably 2-5 km), coverage must be at
  least on a continental scale for observation of
  regional pollution episodes, and must further
  extend on a global scale for observation of
  intercontinental transport and large puff
  releases.
• Temporal resolution and coverage Hourly
  resolution or better
• Enables characterization of
• (1) the synoptic-scale development of
  pollution episodes,
• (2) the diurnal variation of emissions,
• (3) the state of atmospheric composition for
  purposes of inverse modeling and data
  assimilation (forecasting), and
• (4) large puff releases.

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y_Remote_Sensing/index.shtml
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Air Quality Mission Workshop Report to National
Research Council Decadal Survey

• Measurement Requirements
• Vertical resolution The ability to observe the
  boundary layer from space is a major priority for
  air quality applications. For trace gases,
  multispectral methods involving a combination of
  nadir-sounding UV/Vis, near and thermal IR, and
  limb microwave can be used to infer boundary
  layer information on ozone, CO and others, as
  well as providing some vertically-resolved
  measurements for the middle and upper
  troposphere.
• Vertical resolution in the free troposphere is
  important for observing long-range transport, as
  this transport often involves layers of 1 km
  thickness that may retain their integrity over
  intercontinental scales.
• Orbital Requirements Considered LEO, MEO, GEO,
  and L-1
• Orbits have different advantages and
  disadvantages for air quality observations.
  There are important trade-offs among quantitative
  (and achievable) requirements on
• horizontal resolution and coverage,
• temporal resolution,
• vertical resolution.

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y_Remote_Sensing/index.shtml
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Air Quality Mission Workshop Report to National
Research Council Decadal Survey

• Workshop participants reached a consensus that
• multi-spectral sentinel missions (GEO or
  Lagrangian (L-1) orbit) that
• have high spatial and temporal resolution, and
• provide some species concentrations within the
  boundary layer, would be most beneficial to the
  AQ community.
• At the present time, GEO meets this measurement
  capability with the least
• amount of risk
• The greatest societal benefit from a U.S.
  perspective would be derived from placing such a
  satellite in an orbit capable of observing North
  America. The NOAA GOES-R operational suite
  of measurements from GEO will have some AQ
  relevant capability for ozone, carbon monoxide
  and aerosol.
• New generation of dedicated AQ satellite missions
  that will also be part of an integrated observing
  system including air monitoring networks, in situ
  research campaigns, and 3-D chemical transport
  models.

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y_Remote_Sensing/index.shtml