August 19, 20081 NASA Mission Concept Studies for GEO-CAPE S. R. Kawa, S. Janz, R. T. Caffrey, A. Mannino, E. Middleton, L. Purves, S. Bidwell (NASA Goddard.

August 19, 2008 1

NASA Mission Concept Studies for GEO-CAPE

S. R. Kawa, S. Janz, R. T. Caffrey, A. Mannino, E. Middleton, L. Purves, S. Bidwell (NASA Goddard Space Flight Center)

J. Fishman, D. Neil (NASA Langley Research Center)

• Study Process and Objectives• Atmospheres: Science, Measurements, Instruments• + Coastal Ocean: Science, Measurements, Instrument• Mission and Payload Concept• Summary

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Overview of Study Process

• HQ-commissioned Mission Studies (8 primary + 5 combined): – August 2006 to February 2007– Motivation: prepare for recommendations of Decadal Survey– Objectives: identify science requirements, develop instrument and

mission concepts, examine cost versus performance– Science working group, instrument synthesis lab, and integrated

mission design studies for each– Products: design studies and summary reports

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Relevant Mission Studies

1) Geostationary Multi-spectral Atmospheric Composition (GeoMAC): atmospheric chemistry mission only, similar to GEO-CAPE atmospheres

a) moderate resolution scanning UV-Vis spectrometer (GSFC ISAL)b) CO imager in solar infrared and thermal emission (LaRC IDC)c) Imaging Fabry-Perot detector for near-surface O3 (IIP) $850M

2) Integrated Mission #5/Geostationary Multi-discipline Observatory (GMO): combines objectives of GeoMAC with coastal ocean (and terrestrial biosphere), corresponds closely to GEO-CAPE

a) and b) as abovec) very high-spatial resolution event imaging UV-Vis spectrometer (GSFC ISAL) $1268M

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Science Overview: Local Emissions/Global Impact

Tropospheric O3 from OMI and MLS (June ‘05 avg)

[Ziemke et al., 2006]

Local and regional emissions impact ozone and aerosol on local to global scales. Global changes in ozone, aerosol, and other pollutant species impact climate

change and affect local air quality.

Better understanding of the key processes that connect global and local scales is required to accurately simulate, assess, and project these effects in the future.

GEO-CAPE is a mission to investigate the basic science of atmospheric composition and transport processes that underlie our ability to forecast air quality.

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Elements of The (Atmospheric) Science Question

1. What are the emission patterns of the precursor chemicals for tropospheric ozone and aerosols?

1. Quantify spatial and temporal emissions of ozone and aerosol precursors (NOx, CO, hydrocarbons, SO2, particle emissions).

2. What is the evolution of ozone and aerosol through chemical formation and loss, transport, and deposition processes?

2. Measure distributions of ozone, aerosol, and precursors at high spatial and temporal resolution over the US and surrounding regions.

3. What are the influences of weather in transforming and dispersing emissions, ozone, and aerosol?

3. Track transport of aerosol and gases into, across, and out of NA; including large episodic releases from environmental disasters, e.g., fires, volcanoes.

4. What are the regional budgets for air quality criteria pollutants (CO, O3, NO2, SO2, and aerosol) over North America?

4. Characterize regional air quality for model evaluation, assessment, and forecasting.

Mission Science Questions Mission Science Objectives

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Why Geostationary Orbit: Temporal Resolution

Low earth orbit (LEO/sun sync) affords at best one sample per day at a given location in mid latitudes. Key processes occur on relatively short time scales that are not accessible from LEO observations.

O3

SO2

CO

NO2

Local Time (hr)

[Bovensman et al., 2003]

[Bovensman et al., 2003]

NO2

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45

0 3 6 9 12 15 18 21 0 3 6 9 12 15 18 21 0

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0 3 6 9 12 15 18 21 0 3 6 9 12 15 18 21 0

Sur

face

NO

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ppb)

Col

umn

NO

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101

5 m

ol.

cm-2)

OMI Column Measurements

Day 1 Day 2

June 22 Hour of Day (GMT) June 23

CMAQ Model Simulation of NO2

Target continuous hourly sampling of key constituents

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Why Geostationary Orbit:Coverage and Spatial Resolution

Coverage: Once per day samples often obscured by clouds. Spatial Resolution:

- longer Geo time integration allows high SNR/ resolution element- higher spatial resolution improves chance of cloud-free pixel

Target 5 to 7-km pixel resolution over continental field of view.• Consistent with that anticipated for regional chemistry/transport models in the next decade.

• Enable boundary layer O3 determination through cloud slicing

• Potential to transform our understanding of atmospheric composition similar to the way GOES imagery has advanced weather analysis and forecasting.

Tropospheric NO2 from OMI for June 6, 2005

[Bucsela et al., 2006] CO (ppbv) from MOPITT (June 21, 2005)

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Science Traceability Matrix for Atmospheres

Mission Objectives Measurement Requirements

Mission Requirements

Instrument Requirements

Mission Concept Ancillary Requirements

Quantify spatial and temporal emissions of ozone and aerosol precursors

NO2 and HCHO tropospheric partial column, CO with sensitivity in the boundary layer (BL)

Cover US and adjoining regions

Simultaneous constituent measurements

Continuous daytime coverage

High spatial resolution (5 km) to resolve source locations and sample between clouds; high precision detection (SNR>1000:1)

CO measurement in reflected sunlight

Instruments in geo orbit continuously scan populous N America coast-to-coast.

UV/Visible spectrometer measures O3, NO2, HCHO, SO2, and aerosol column density; plus CO, O3 detectors for BL and free trop

Surface in situ and remote sensing monitoring network; in situ aircraft and balloon mmts; stratospheric O3, NO2, and dynamics

Inverse models for source inference.

Measure distributions of O3, aerosol, and precursors at high spatial and temporal resolution over the US and surrounding regions.

O3 partial column; O3 with sensitivity in PBL; aerosol optical depth

Measure diurnal changes of constituents

Map sunlit earth at near-nadir

Hourly sampling frequency in polluted regions

View upwind and downwind of the continent

Day/night CO and O3 sampling

Spectrally resolved, high-SNR reflected UV/Vis radiances

O3 measurement in thermal emission bands (and/or reflected sunlight)

CO measurement in thermal emission bands

Ability to stare at target region from geo enables high-resolution ground sampling at high SNR.

Hourly or better sampling frequency during daytime for UV/Vis, and during day and night for free-troposphere CO and O3.

GOES T, H2O profiles, surface, and upper-air weather observations; accurate, detailed meteorological analyses

3-D global chemistry-transport model integrations

Process-oriented research field campaigns

Track transport of aerosol and gases into, across, and out of NA; including large episodic releases from environmental disasters

CO in mid-troposphere; O3, NO2 tropospheric partial columns; aerosol optical depth, SO2 column density

Characterize regional air quality for model evaluation, assessment, and forecasting.

O3, NO2, HCHO, CO partial columns; O3 with sensitivity in PBL; aerosol optical depth

Accommodate large data collection and retrieval rates;

2-5 yr mission lifetime

Continental field of regard; hourly temporal resolution in polluted regions

High-resolution, frequent sampling maximizes lower troposphere data in presence of clouds

Data assimilation methodology;

Regional mesoscale chemistry-transport modeling

9Goddard Space Flight Center

Instrument Suite ConceptInstrument Suite Concept

1. UV/Vis- Scanning UV/Visible spectrometer (300 – 480 nm); detect total column O3, NO2, HCHO, SO2, and aerosol; limited efficiency for O3 in the boundary layer.

• CO Detector- Gas correlation filter radiometer measuring in reflected near-IR and thermal IR emission; senses atmospheric CO total column to surface and mid- and upper-troposphere weighted; separate boundary layer from free troposphere abundance.

• Trop O3

- Imaging Fabry-Perot spectrometer for O3 in the thermal IR; sensitivity decreases near the surface more slowly than UV/Vis; determination of near-surface O3 in combination with UV/Vis.

Measurements all need to be made closely in time and space to enable detailed examination of transport and photochemical processes, e.g., O3 production from CO oxidation:

CO + OH + O2 CO2 + HO2

HO2 + NO OH + NO2

NO2 + h + O2 NO + O3

Diurnalprocessstudies

IncreasingTropospheric

return

GeoMAC

OMI TOMS GOMETES MOPITT

10Goddard Space Flight Center

Measurement Requirements and Instrument Suite

Trace Gas Needed mixing ratio precision

Needed accuracy

Column density capability* [molecules cm-2]

Instrument Requirement [SNR]

Instrument Implementation

NO2 0.2 ppbv 20% 5.0 x 1014 2000 (430 nm) UV/VIS grating spectrograph:

Cost effective broadband measurement at moderate spectral resolution (< 1nm).

High spectral stability and throughput. Strong heritage.

HCHO 1.0 ppbv 20% 2.5 x 1015 1500 (350 nm)

O3 10 ppbv (troposphere)

10% 1.3 x 1016 1000 (320 nm)

SO2 Not applicable 20% 2.2 x 1016 500 (312 nm)

O3 10 ppbv

(troposphere)

10% 1.3 x 1016 100 ( 9.6 m) Fabry Perot Interferometer:

Successful IIP.

CO 10 ppbv 10% 1.0 x 1017 2500- 9500 ( 2.3 m)

(scene dependent)

Gas Filter Correlation Radiometer:

Target gases with very high sensitivity/resolution. Multi-spectral for robust retrieval and to separate PBL from free trop. Strong heritage.

CO 10 ppbv 10% 1.0 x 1017 700 (4.67 m)

Near-surface CO

10 ppbv 10% 1.0 x 1017 Not applicable Inferred from multispectral analysis

Near-surface O3

5 ppbv 10% 1.3 x 1016 Not applicable Inferred from multispectral analysis

Trace gas sensitivity required to meet science goals

* Assumes PBL height of 1 km. Additional information on science requirements can be found at http://qp.nas.edu/QuickPlace/decadalsurvey/Main.nsf

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• Measurement demonstration and technical feasibility completed under NASA Instrument Incubator Program.

• No technical hurdles to instrument or spacecraft.• Pointing requirements are commensurate with GOES.• Detector optimization, single crystal silicon mirror

testing, and aircraft demo recommended for technology readiness level 6.

Performance Data Technology Assessment / Development Needs

• Measure atmospheric pollutants O3, aerosols, and precursors NO2, SO2, HCHO.

• Field of regard: Western Hemisphere with emphasis on continental United State

• Sample revisit time of 1 hour, during sun illumination.• Mission Design Life: 2 years, goal 5 years

(consumables sized for 5 years), launch Sept. 2014.

Measurement Concept

Star Tracker (1 of 2)

Calibration Assembly /Calibration Aperture

Optical BenchOpticsAperture and Scanning Mirror

Gyroscopes

Thermal Radiator

1700 mm

860 mm

830 mm

From ISAL

• Single focal plane, continuous band from 300 nm to 480 nm.

• Spectral resolution: 0.8 nm. • Signal-to-noise ratio of 720 at 320 nm and 1500 at 430 nm.• Typical scanned field-of-view: 8° N/S (5000km) x 8° E/W

(5000 km). Can point anywhere on visible hemisphere.• Pointing stability maintained through active jitter

compensation.• Sample spatial resolution 1.25 km N/S x 5.0 km E/W.

Scanning UV/Vis Spectrometer

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Carbon Monoxide Detector

Instrument Performance DataTechnology Assessment / Development Needs

Measurement Concept• Gas correlation filter radiometer measures CO in near-IR

reflected sunlight and thermal IR emission.• Spectral combination approach identifies CO boundary

layer distribution from space.• Measures CO, an atmospheric pollutant precursor of O3

and primary indicator of combustion.• Continue outstanding performance of MOPITT; scientific

findings based on MOPITT data demonstrate the measurement maturity and technical feasibility.

• Detector: Use of large format 2-D arrays in space (no scanning)

• Data array: 1024 x 1024 pixels for each SWIR & MWIR• Spatial resolution: 5 x 5 km2; spectral resolution better than

0.1 cm-1 provided by gas filter.• Each spatial pixel requires frame averages to achieve

SNR. • Onboard calibration: blackbody targets, deep space and

solar views

• Technology for this instrument is at high readiness level.• Measurement Heritage: MOPITT, HALOE• Beneficial investments:

- Radiation hard high performance electronics- Light weight thermal control and structural materials

Dimensions: 1.31 x 0.55 x 0.43 m

From LaRC IDC

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Multi-discipline Science Questions

• What are the effects of gaseous and particulate emissions and climate variability and change on global atmospheric composition, and how will future changes in atmospheric composition affect ozone, climate, and regional/global air quality?

• How are coastal ocean ecosystems and the biodiversity they support influenced by climate or environmental variability and change, and how will these changes occur over time?

• What is the current geographical distribution, composition, and health of the terrestrial biosphere around the world, and how are its component ecosystems responding to climate changes?

(from Strategic Plan, Sub-Goal 3A: 3A.1: Progress in understanding and improving predictive capability for changes in the ozone layer, climate forcing, and air quality associated with changes in atmospheric composition; 3A.3: Progress in quantifying global land cover change and terrestrial and marine productivity, and in improving carbon cycle and ecosystem models [NASA 2006]).

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Coastal Ocean Spatial Resolution

Sample coastal waters at 300-m resolution

250 x 500 km scan/15 min

Measurement Objective: Ecosystem carbon, physiology and functional type with event scale multiple observations per day.

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Ocean Ecological Products

Critical products: Primary productivity, chlorophyll, particulate organic carbon, dissolved organic carbon (DOC), colored dissolved organic matter (CDOM), fluorescence line height, calcite, phytoplankton physiology and functional type (including harmful algal blooms).

DOCCDOM(355)Chlorophyll

A2006132

16Goddard Space Flight Center

What is the current distribution and species or functional type composition of the major forest and grassland ecosystems and agricultural systems?

What is the status of disturbance and fragmentation in these systems?

What is the temporal variation in biogeochemical processes (e.g., transpiration, light use efficiency, nutrient uptake) that affect productivity in these ecosystems?

How are terrestrial ecosystems affected by and responding to climate variability and change?

Elements of the Science Question for Elements of the Science Question for Terrestrial BiosphereTerrestrial Biosphere

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Imaging Spectroscopy for Terrestrial Biosphere

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Observatory Concept

Combine instrumentation to enable coastal ocean and terrestrial biosphere science and enhance atmospheric science.

• Combination of medium-

resolution (5 km) continental

scanning instruments with

high-resolution (300-m) regional

viewing spectrometer.

•Very high spatial resolution, programmable geosynchronous multi-disciplinary observatory.

• Shared resource for regular observations, special observing studies, and emergencies

•Precursor designs in ESEI, COCOA, GEOCarb.

•Meet or exceed discipline science measurement requirements.

•Potential ground-breaking new science in each discipline plus synergies.

Washington, DC imaged with 5-km pixels.

Continuousscan of polluted regions

Programmable high-resolution observations

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Multi-discipline Instrument Requirements

Coastal Ocean Atmosphere Biosphere

Spectral Bands(nm)

340-1100, 1240, 1640

300-480, 400-600, 2300, 4600

400-1300, 2000-2300

SNR >1000 in UV-VIS 1000 >800

Spectral Resolution

1-5 nm <1 nm UV1-2 nm Vis

5-10 nm

Spatial Resolution

100-300 m >1 km <250 m

Temporal Resolution

3-6 / day ~ hourly 3-6 / day

Spatial Coverage ~320 km Ocean adjacent to coast; estuaries, bays, rivers, large lakes

200 kmPolluted urban areas

200 kmEcosystem area

Radiometric Stability

<0.1% band-to-band 0-10 hours

<0.1% band-to-band 0-10 hours

<0.1% band-to-band 0-10 hours

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Multi Discipline Imager (MDI)

• Mirror stabilization system for image generation will require further development to meet the required precision.

• Large size drives cost, risk; need to optimize for science and feasibility.

Instrument Performance Data

Technology Assessment / Development Needs

Instrument Concept• Enable scientific objectives of coastal ocean, atmosphere,

and biosphere.• Capable of pointing anywhere on visible Earth

hemisphere.• Measurement parameters adjustable: dependent on

science objective.• Employs three focal planes/bands

Two Si: 1k (spectral) x 2k (spatial) Rockwell hybrid focal planeOne HgCdTe: 256 x 2k Rockwell hybrid focal plane

4.5 m 3.0 m

1.2 m

• Spectral Bands: 300-556, 340-1139, 1240, 1640 nm• Spectral Resolution: 0.75 (3x sample), 0.8, 40, 40 nm• SNR: > 1000 (bands 1, 2); > 500 (bands 3, 4)• Spatial Resolution: 300 m pixels, Coverage: 500 km• Temporal Resolution: < 1 hour

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Satellite Mission Concept

Features

Technology Development NeedsSC Bus & Launch Vehicle

- None (over 20 geostationary launches/year)

• Instrument Complement: MDI Ins, UV/Vis, CO Detector

• Launch: ~FY2014• Launch Vehicle: Atlas V 401 or Delta IV 4040-

12• Orbit Type

• Geostationary• 100 Degree W Longitude

• Real-Time Science Data Downlink with Dedicated Ground Station

• Disposal into Geo + 300 km Parking Orbit

Performance Data (with margins)

• Mass: 1286 kg (payload), 4679 kg (observatory wet total)

• Power (Average): 930 W (payload), 1625 W (total)• Data Rate: 120 Mbps (payload), 179 Mbps (total), • Spacecraft Pointing (1 sigma ): 30 arc-sec control, 4

arc-sec knowledge• Lifetime (years): 2 (design), 5 (goal & consumables)

MDIInstrument

UV/Vis Spectrometer CO Detector

Earth

Est. Cost: $1.3B

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Other Considerations

• Spacecraft and launch vehicle• Advanced technology investments• Ground system architecture• Mission operations• Cal/Val requirements, Validation program• Supporting research and analysis• International cooperation

No show stoppers

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Outstanding Questions

• Can the mission be made more affordable?– science requirements versus instrument performance/size

• Do instruments have to fly together?– piggy-back on commercial communication satellite?

• Can other instrument concepts fulfill measurement requirements?

– cost, benefit, risk assessment

• Priority and feasibility of boundary layer O3 measurement?

Community input Observing system simulation Airborne demo measurements

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Alternate Instrument Concepts

Coastal Ocean Carbon Observations and Applications (COCOA)

Further Design Study

SpecificationsInstrument mass: 45-60 kgPower: ~50 WCost: 12-20 Million (USD RY)Optics: F/5 Cassegrain; all beryllium optics and structure; Offner SpectrometerFocal Plane Array: Commercial visible detectorLength: 120 cmPrimary Mirror: 70 cm diameterSecondary Mirror: 20 cm diameter

PerformanceSpatial Resolution at Nadir: 200 meterSpectral Resolution: 5 nm between 350 and 1050 nm (140 bands)Signal to Noise: exceeding 400 between 400 nm and 900 nm

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Summary

Strategic Concept: An Earth-viewing, Hubble-like programmable observatory facility.

Geostationary orbit enables continuous, frequent, high spatial-resolution observations required to provide the scientific foundation for quantitatively connecting local and global scales of pollution, coastal ocean, and land carbon. new and unique approach to satellite remote sensing for atmospheric composition, coastal ocean properties, and the terrestrial biosphere no major technological impediments

Need to work hard to make concept more affordable.

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Option to Reposition Geo Longitude

Mission design study needed to determine drift rates, fuel load, ground communication requirements.

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Science Working Group

• Multi-Spectral Atmospheric Composition:P. DeCola (HQ, chair)S. R. Kawa (GSFC, Geo science lead)P. K. Bhartia (GSFC, LEO science lead)

J. Crawford (HQ)E. Hilsenrath (HQ)M. J. Kurylo (HQ)H. Maring (HQ) W. H. Brune (Penn St U)D. Edwards (NCAR)M. Prather (UC Irvine)R. Prinn (MIT)A. Eldering (JPL)J. Fishman (LaRC) J. G. Gleason (GSFC) Additional acknowledgement to: J. Loiacono, B. Park, J. Herman, R. Knox (GSFC);

J. Burrows (U Bremen); C. Bruce, M-E. Carr (JPL); G. Sachse (LaRC)

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Terrestrial Vegetation Opportunity

(250 km)2 scan/15 min

Scan forest at 300-m resolution