Ceres status bruce a wielicki nasa langley research center aqua status meeting nasa hq aug 23 2005
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CERES Status Bruce A. Wielicki NASA Langley Research Center Aqua Status Meeting NASA HQ, Aug 23, 2005 PowerPoint PPT Presentation

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CERES Status Bruce A. Wielicki NASA Langley Research Center Aqua Status Meeting NASA HQ, Aug 23, 2005. CERES Summary: New Science.

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CERES Status Bruce A. Wielicki NASA Langley Research Center Aqua Status Meeting NASA HQ, Aug 23, 2005

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CERES StatusBruce A. WielickiNASA Langley Research CenterAqua Status MeetingNASA HQ, Aug 23, 2005

CERES Summary: New Science

  • Large variability in Global Ocean Heat Storage and ERBS/CERES global net radiative fluxes agree to within 0.4 Wm-2 (1s) for 1992-2002. (included in IPCC AR4 and submitted to J. Climate)

  • Earthshine albedo change reported in Science, 2004

    • Earthshine claims 6 Wm-2 increase in reflected flux 2000 to 2003

    • CERES claims 1 Wm-2 decrease (Wielicki et al., Science, May 2005)

    • Have engaged Earthshine authors for direct CERES/Earthshine comparison: expect Earthshine aliasing and sampling errors large

  • GEWEX international Radiative Flux Assessment is underway

    • Co-chaired by Wielicki, Stackhouse, Raschke, Ohmura

    • TOA and Surface flux assessment of decadal change/uncertainties

    • First draft in late 2005, final in late 2006. Relevant to IPCC AR4.

    • CERES data and validation results are major contributions.

  • New approach to cloud model testing: CERES cloud properties/radiative fluxes versus Cloud Resolving Models and ECMWF global model (Xu et al., J.Climate July 2005).

  • CERES/MODIS and ISCCP tests of climate model cloud properties (Zhang et al., JGR, May 2005, likely IPCC AR4).

Ocean Heat Storage vs. Satellite Radiation Data

Recover ERBS

Nov 99 - Aug 05

by allowing for

15 degree tilt

angle change

Wong et al., submitted to J. Climate

B. A. Wielicki

CERES rejects Earthshine 6% albedo anomaly









CERES Summary: New Science

  • AMS BAMS publication of NASA/NIST/NPOESS Satellite Climate Calibration Report, Sept 2005.

    • SW/LW/Net flux goals of 0.3/0.2/0.3 Wm-2 per decade (0.1 - 0.3%)

  • Stackhouse completing FlashFlux using CERES code:

    • near real-time version (3-4 days after acquisition) of CERES level 3 gridded TOA/Surface fluxes

    • lower accuracy sufficient for use in seasonal to interannual prediction: constrain ocean surface fluxes on weekly basis

  • Mlynczak has begun a combined CERES-AIRS isolation of the far-infrared (15 to 100 micron wavelengths): unexplored and dominates the water vapor greenhouse effect.

  • CERES is now engaging the major climate modeling groups in comparisons of new cloud/radiation data

    • new Multi-Model Framework (CSU, LaRC, GSFC effort)

    • new CERES cloud objects & 4-D weather forcing data now online

    • standard climate model statistics including seasonal cycles

    • new concepts like Perturbed Physics Ensembles

  • New A-train subset of CERES/MODIS/CALIPSO/Cloudsat along the active sensor profile (60km swath) in development (NEWS)

CERES Summary: Aqua Data Products

  • CERES Science Team Meeting May 2005, GFDL Princeton.

    • Engage GFDL climate modelers

    • Next meeting will be Nov 1-3 at LaRC

  • Aqua Level 1 Radiances and ERBE-Like TOA Fluxes

    • Nominal production of Ed1 and Ed2 data products (avail to April 2005)

    • Rev 1 for RAP vs Crosstrack scan SW cal change in Data Quality Summary

    • Rev 2 will provide scene type dependence of SW change (Nov 2005)

  • Aqua Level 2 TOA, Surface, and Atmosphere Fluxes, ADMs

    • Edition 1 SSF (merged MODIS cloud/CERES) in production using Terra ADMs for first processing.

    • 2 years of Aqua SSF Ed1 used to produce Aqua ADMs

    • Expect Aqua ADMs complete/validated/approved at Nov 2005 meeting.

    • Dec 2005 Aqua Ed2 processing begins with new Aqua ADMs, in time for merging with CALIPSO and Cloudsat on the A-train.

    • Full 3 years of Aqua L2 (TOA to Surface fluxes) in archive by Summer, 2006.

  • Aqua Level 3 products

    • Once ADMs are complete, these will lag level 2 reprocessing by about 1 month.

What are CERES Next Steps?

  • Completing CERES constraint of geo shortwave diurnal cycles

    • correcting time/angle differences in 1 degree monthly grid box

  • Closing the global net energy budget to from 5 Wm-2 to 1 Wm-2

    • solar constant (1), ocean heat storage (1), diurnal (3?), cal (2).

  • Completing studies of interannual variations of global albedo, LW flux, and Net flux

    • RAP vs Crosstrack scanner comparisons have been critical

    • Using Terra FM2 CERES to test scan mode contam effects: so far appears to be only RAP mode: no effect on normal crosstrack.

  • Completing 3-hourly synoptic and monthly average products

  • Validation against GERB diurnal cycles

    • CERES will serve as GERB SW reference, GERB as diurnal cycle

  • Validation against A-train aerosol/cloud profiles: esp. polar

  • Improving polar ADMs (3x larger errors than other regions)

  • Merging with A-train data for aerosol and cloud research

  • Implement code to handle FM-4 without SW channel

    • use night to constrain MODIS => CERES LW.

    • in day use CERES Total minus MODIS LW = CERES SW.

CERES/Aqua FM-4 SW Anomaly



  • On March 30, 2005 at 18:42 GMT the CERES/Aqua FM-4 instrument stopped collecting valid Shortwave channel radiometric measurements.

  • Failure was characterized by an immediate railing ‘high’ of the SW channel data stream, which subsequently drove the SW channel bridge balance electronics into a reset condition to bring the SW channel output on-scale.

  • The Total and Atmospheric Window radiometric channels continued to function nominally.

  • All other housekeeping and science parameters remained within nominal ranges and continue to do so. No increased noise or precursor indicators prior to event.

  • Anomaly resolution team formed on March 31st and developed a strategy to guide the investigation. NGST is included on the team.

  • Despite all attempts to revive it, the SW channel remains unusable, characterized by significant ‘noise’ and a rapidly varying zero point.

Instrument Operations

Satellite Direction

Onset of the anomaly for the CERES FM-4 SW Channel at ~18:42 GMT 03/30/05. Plotted are the geo-located SW channel measurements. The black and red striping indicates ‘railed’ data at either 0 or 4095 counts.

CERES/Aqua FM-4 SW Anomaly

Analysis and Recovery Efforts


  • Anomaly resolution team formed on March 31st and developed a strategy to guide the investigation. NGST is included on the team.

  • ~24:00 GMT March 31st, the CERES/Aqua FM-3 instrument was placed in the Cross-track scan mode to preserve the CERES Climate Data Record measurements.

  • Complete memory dump of the FM-4 instrument was accomplished on 4/1/05. Indicated no corruption of the flight software or memory locations, discounting SEU.

  • Flight Software autonomous bridge balance bias control bypassed on SW channel in favor of manual control in attempt to maintain sensor output on-scale.

  • Completed P-Spice modeling effort to characterize anomaly and test failure modes.

  • Compared SW science output to MODIS in an attempt to quantify gain changes.

  • Elevated, by ~2-deg C, the temperature of the Sensor Electronics Assembly board by raising the detector heatsink temperatures.

  • Bias voltage necessary to keep sensor output on-scale continues to trend back towards pre-anomaly values, but we see no improvement in sensor noise.

CERES/Aqua FM-4 SW Anomaly

Failure Hypotheses

  • There has been a failure of one of the resistors in the Sensor Electronics Assembly SW channel circuitry.

    • Characterized by an abrupt shift in resistance followed by a fairly rapid oscillation (+- 10’s of ohms) about the nominal resistance (>100K)

  • P-Spice model used to test failure hypotheses, we do not have the capability to probe this circuitry via flight software to isolate the faulty resistance.

  • CERES does utilize Vishay resistors which have been implicated in failures on other projects.

    • Failure required to produce the current symptoms is different from previous Vishay failures. These demonstrated much larger increased resistances (10’s of K) with an oscillation between the nominal and increased value.

    • CERES Project was aware of issues with Vishay, TRW implemented additional screening procedures prior to acceptance.

  • The CERES bolometers are one of the resistors in this electronics circuit.

    • A delamination of the SW thermistor could also produce the anomalous symptoms.

CERES/Aqua FM-4 SW Anomaly

Future Directions and Impacts


  • The radiometric performance of the two remaining channels remains nominal.

    On-Going Work

  • Current plan is to complete recovery efforts by 9/1/05.

  • Will drop SEA temperature 2-deg C below nominal for approximately 1-week in attempt to perturb sensor output

  • Subsequently we will continue to monitor performance and manually attempt to maintain SW sensor output on-scale.

    Operational Implications

  • Anomaly team is confident this is a part, and NOT a design issue.

  • Team has not identified any operational modifications.

  • Little to no impact with regard to the anticipated lifetimes of other CERES instruments.

CERES/Aqua FM-4 SW Anomaly

Science Impacts

Near Term

No impact: the CERES/Aqua FM-3 instrument is collecting global cross-track data.

2 years of Rotating Azimuth Scan data already required for Aqua ADM development.

Total and Window channels unaffected. Process without SW channel in near-term.

Long Term

If anomaly cannot be resolved, longer term science issues include (in order of priority)

  • significantly increased risk of a gap from Terra/Aqua climate record to the beginning of

  • NPOESS using FM-5 in 2011/2012 (from 7% to 12% risk: exceeds 10% goal). Assess CERES Total minus MODIS LW = broadband SW to minimize impact.

  • the second Aqua CERES instrument for the A-train was to scan along-track for multi-

  • angle views over the lidar/radar track to examine effects like 3-D radiative transfer. Assess CERES total minus MODIS LW = broadband SW to minimize impact.

  • the second Aqua CERES instrument is also used to perform intercalibrations with GERB:

  • but these can be accomplished by the second Terra CERES as long as two CERES

  • instruments are active on Terra

  • the second Aqua CERES instrument is also used during cloud/aerosol field experiments

  • to provide multi-angle data that tracks a pre-selected surface site (e.g. ARM site).

Backup Slides

CERES vs ERBE Cloud Forcing

3 to 5 Wm-2 differences

doubling CO2 ~ 3 Wm-2

Only CAM2 climate model yet

agrees with CERES even on

global mean cloud forcing:

seasonal and zonal errors

are much larger

Climate Models vs

CERES Cloud Forcing

(DJF 60N-60S)

Zhang et al., 2005

DJF Zonal Mean Cloud

All Models show poor

dependence on latitude

and cloud height: larger

than differences of


Climate Models vs


ISCCP Cloud Data

Zhang et al., 2005

DJF Zonal Mean Cloud

All Models show poor

dependence on latitude

and optical depth: larger

than differences of


Climate Models vs


ISCCP Cloud Data

Zhang et al., 2005

JJA - DJF Seasonal Changes:

All Models show better

performance for seasonal

changes in cloud type

than for mean properties,

but still very large errors

vs climate change goals

when compared to


Climate Models vs


ISCCP Cloud Data

Zhang et al., 2005

DJF Cloud Types by

Height / Optical Depth Class

Large climate model errors

by cloud type

Climate Models vs


ISCCP Cloud Data

(DJF, 60S - 60N)

Zhang et al., 2005

CERES/Aqua FM-4 SW Anomaly


March 30, 2005

We should regularly evaluate gap risk for all satellite variables....

For U.S. CERES-like fluxes: Terra, Aqua, NPOESS in 2012 (black line in plot. )

CERES Science Team: Bruce A. Wielicki, Principal Investigator

Phase II: 2004-2007

Adds university, NCAR, GSFC

researchers. 30 science team members

Terra/Flight Model 1Lifetime Radiometric StabilityDetermined with the Internal Calibration Module



0.5% LW

1% SW

1% Window

Stability Goal:

better than

0.5% per

5 years

Normalized to Ground Calibration Data

Jan/Feb 98 El Nino TOA LW Flux Anomalies

TRMM CERES Satellite Observations

NOAA GFDL Older Climate Model (AMIP observed SSTs)

NOAA GFDL Newer Climate Model (AMIP observed SSTs)

Tropical (20S - 20N) TOA Radiation Anomalies:Observations vs. Climate Models

Edition 3 ERBS with

altitude & day/night


Net radiation increase

in the 90s vs late 80s

Dominated by SW

Wong et al., submitted

Stainforth et al.,

2005, Nature

Amount of change for a factor of 6 in climate model sensitivity, by climate variable: clouds dominate

  • Results from Murphy el al., Nature, Aug 04

  • 58 different climate models

  • Range of climate sens. is factor of 5

  • 31climate metrics (plot)

  • Bars are 25 to 75th pctile

  • Height of line is min to max

  • Non-dimensional scaling is to interannual variability (noise)- “Signal to noise”

  • Clouds/radiation dominate

How accurate must measurements be

to constrain equilibrium global cloud feedback?

Global SW Flux Change/ Decade (Wm-2)

Change in Climate Sensitivity Caused by Cloud Feedback (1 = no change)

  • Regional changes will be larger: but no constraints on magnitude.

  • UKMO ensemble climate noise annual tropical mean SW and LW fluxes ~ 0.3 Wm-2

GEWEX Radiative Flux AssessmentTOA and Surface Decadal Radiation Consistency and UncertaintyCommunity Web site at the NASA Langley Atmospheric Sciences Data CenterPreliminary Report late 2005, final 2006

uses CERES data only









CERES is a Sensor Web: up to

11 instruments on 7 spacecraft

all integrated to obtain climate

accuracy in top to bottom fluxes


3-hourly 1-degree grid



100 km


0.1 micron


50 km


100 km


100m - 1km

cloud cell

Range of Cloud/Aerosol/Radiation Model Tests

New CERES ADMs greatly improve instantaneous fluxes

Key to constraining more accurate surface fluxes

Key to accurate cloud fluxes by cloud type

Key to accurate matched satellite/surface fluxes for aerosol absorption

CERES TOA instantaneous shortwave fluxes differ from ERBE by +/- 50 Wm-2 with a strong dependence on scene type & viewing angle

Use CERES Rotating Scanner hemispheric scans over two years to

verify climate accuracy (large ensemble biases in new angular models:

direct hemispheric radiance integration over 2 years provides truth.

Factor of 2 to 10 improvement relative to ERBE. Edition 2 (ED2) are

Terra ADMs used in new Edition 2 CERES Data Products

ED1 used


and theory

for snow/ice


ED2 uses

Terra ADMs

and Terra


snow/ice ADMs

CERES: First Radiative Fluxes Accurate by Cloud Type

Differences of new CERES SW fluxes from ERBE-Like zonal means for

March 2000. Differences up to 8 Wm-2.

Will impact equator to pole transport, surface flux constraints with ARGO

on ocean mixing processes, climate model validation

New ADM Impact

New Geo 3-hourly

sampling impact

ARM Central Facility, Downward LW Fluxes

CERES estimate (y-axis) vs ARM Surface Measurement (x-axis)

All-sky, 715 CERES Overflights within 1 minute,

Day and Night Overpasses, Nov 00 to Sep 01

For BSRN sites

equator to pole

Bias < 5 Wm-2


sigma 15 to 25 Wm-2

Total of 60,000


Bias < 1 Wm-2,

Sigma = 15 Wm-2

Overcast Boundary Layer Cloud Systems : Observed CERES Cloud Objects for March,1998

Sample individual pdfs

for just 8 of the stratus

cloud systems

(CERES SSF TOA albedo)

Weather: can we predict

why they vary? SST?

wind shear? boundary

layer height?

Climate: can we predict

the ensemble mean vs

change in SST, wind

shear, etc? Feedbacks

in partial derivatives

Xu et al., in preparation

Boundary Layer Cloud Systems: Observed CERES TOA Albedo Pdfs for March, 2000 La Nina vs March, 1998 El Nino

No apparent difference in the

S.E. Pacific, even though

the Walker Cell strength reduced,

Hadley cell strengthened...

S. E. Pacific, March 2000

S. E. Pacific, March 1998

Suggests stable properties by

cloud type: next step to quantify

how stable.... 1 Wm-2 ? 0.1 Wm-2?

Large Deep Convective Cloud Systems: Ht > 10km, tau > 10, Fraction = 1, Diameter > 100kmMarch, 1998, 25N to 25S

CERES Observations

Cloud Resolving Model (2km 2-D)

ECMWF initial conditions,

advective tendencies

Cloud Object Data

available at:



(50 km 3-D)

Xu et al., 2005

“A-Train” Formation for Aerosol and Cloud Vertical Profiles

Atmospheric State => Aerosol/Cloud => Radiative Heating

What are the Next Steps?

  • Take advantage of the new observations and climate model approaches:

    • New ~ 1km Cloud Resolving Models inside climate models: MMF

    • New scaled earth (DARE) models with clouds to 100’s m

    • New Perturbed Physics Ensembles: 1000s of Earth Like Planets

    • Merging Aerosol transport models with cloud resolving models

    • As Terra record length increases toward a decade, its power for climate studies increases dramatically:

      • Ocean heat storage

      • Cloud feedback

      • Aerosol Indirect Effect and Direct Effect

      • Polar climate change

    • As Terra, GERB, Aqua and A-train observations are combined:

      • Improved cloud and radiation diurnal cycles

      • Full multi-layer vertical cloud and aerosol profiling

    • Multi-scale modeling/observation attacks on aerosol/cloud/radiationthe “holy grails” of current climate forcing and future sensitivity

How do we determine climate prediction uncertainty?IPCC is just climate model differencesHow do we set climate observing system requirements & priorities?Global mean constraints aren’t enough

How do we relate model errors versus observations to climate prediction uncertainty?

  • PPE Planet “I” vs Planet “J” is a simulation of Climate Model vs Earth

  • Each Planet is a different Earth-like physical climate system

  • Planets have physics which differ in processes we don’t understand

  • Can we use these Planet’s past climate differences to predict differences in their future climate?

  • This is in fact the same as asking if we can use past climate differences in Earth vs Climate Model to predict uncertainty in predicting the future climate of Earth.

  • If this is not successful: we cannot predict uncertainty in predicting the real Earth: until after the fact.

Neural Net Structure

Input Variables

Planet “I” - Planet “J”

base state CO2 climate



Total Cloud Fraction

Conv. Cloud Fraction

Total Precipitation

Large Scale Snowfall

Large Scale Rainfall

Surface Latent Ht Flux

Surface Net SW Flux

Surface Net LW Flux

Surface Net Radiation



Output Variables

Planet “I” - Planet “J”

2xCO2 minus 1xCO2

Surface Temperature

Summer U.S. Precip

Sea Leveletc...

Neural Net Prediction of Climate Sensitivity

Planet “I” minus Planet “J”

Doubled CO2 Global Temp Change

95% confidence bound

of +/- 0.8C

33 climate model variables

Neural Net Prediction: Doubled CO2 Global Temp Change

(uses Planet I and J normal CO2 climate only)

Y. Hu, B. Wielicki, M. Allen

Linear Regression Prediction of Climate Sensitivity

Planet “I” minus Planet “J”

Doubled CO2 Global Temp Change

95% confidence bound

of +/- 0.8C

95% confidence bound

of +/- 2.0C

33 climate model variables

Neural Net Prediction: Doubled CO2 Global Temp Change

(uses Planet I and J normal CO2 climate only!)

Y. Hu, B. Wielicki, M. Allen

Climate Calibration Observatory Summary

  • Calibration first design: linear, stable, full solar/ir spectra

  • Intercalibration design for precessing orbit/large fov/pointing

  • Launch on demand to reduce gap risk to < 1%.

  • Two observatories allows independent calibration confirmation

  • Provide a few hundred intercalibration samples for other instruments per year

  • Allows a way to deal with uncertain NPOESS future calibration

  • Allows calibration of geostationary imagers/sounders

  • Allows calibration checks of international and U.S. missions

  • CERES Rotating Azimuth plane scanner has demonstrated planned intercalibration campaigns for precessing vs. sunsynchronous vs. geo orbits for CERES and GERB. Matches in time/space/angle

  • Turns around our normal space mission design to a different paradigm to support climate change.

  • For Climate Remote Sensing: Calibration is the 1st dimension.

    • The other 8 are: x, y, z, t, wavelength, s. zenith, v. zenith, v. azimuth angle.

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