MOPITT CO

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MOPITT CO

• Louisa Emmons, David Edwards
• Atmospheric Chemistry Division
• Earth Sun Systems Laboratory
• National Center for Atmospheric Research

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MOPITT CO 700 hPa CO Zonal Average Mixing Ratio

• The Northern Hemisphere winter maximum occurs
  March-April
• The peak of the Southern Hemisphere biomass
  burning maximum occurs each year in
  September-October with variable intensity
• Most monthly anomalies can be attributed to
  sporadic wildfires and variations in annual
  biomass burning

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Near-Real-Time MOPITT CO Retrievals

• For field campaigns (e.g., INTEX-B) we can
  request expedited data within a few hours of
  overpass for region of interest

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Rapid Response Data

• As part of our standard procedure we produce
  retrievals within 1 day based only on MOPITT
  measurements (60S-60N)

April 20, 2006 - 700 hPa
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Operational Retrievals

• Make use of MODIS cloud mask product, so are not
  available until that is received (at least 2
  days)

April 20, 2006 - 700 hPa
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MOPITT CO Retrievals

• MOPITT CO retrievals are determined by maximum
  likelihood (optimal estimation), incorporating a
  priori information.
• The retrieved profile x' can be expressed as a
  linear combination of the true profile x and the
  a priori profile xa.
• x' A x (I-A) xa
• The Averaging Kernel A represents the measurement
  sensitivity to the true profile. I is the
  identity matrix.
• Averaging kernels depend on the contrast between
  air and surface temperature and surface
  emissivity.

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Transformation of in situ Profiles

• The averaging kernels and a priori CO profile are
  used to calculate x' from in situ CO (x)
• x' A x (I-A) xa
• For example, x'(700 hPa)
• A700 x
  (I-A700) xa

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MOPITT x x'
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MOPITT/MOZART in INTEX-B
Investigating the transport and transformation of
gases and aerosols from Asia on trans-Pacific
scales and assess their impact on air quality and
climate

• Campaign flight planning is aided by the ability
  to forecast the occurrence of pollution plumes
• For the Spring 2006 NSF/NCAR MIRAGE and NASA
  INTEX-B campaigns, a pollution plume predictive
  capability was provided by the assimilation of
  near-real-time MOPITT CO data into the MOZART CTM

NASA DC-8 from NCAR C-130
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Forecasting Pollution Plumes

• For each day of MIRAGE INTEX-B
• MOZART with assimilation of MOPITT CO and full
  chemistry (2.8x2.8) run for past 3 days
• CO forecasts initialized with assimilation
• 3 day forecast CO and tags run at 0.7x0.7 for
  flight planning

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Plume Origins
MOPITT 700 hPa CO April 06 This was fairly
typical cf. the same month during other MOPITT
years
MOZART Tracer _at_ 500 hPa 36 hr Fx 1000 UTC 24 Apr.
SE Asia bb

• CO emissions from different regions and sources
  were tagged to identify different contributions
  to the observations
• Chinese emissions dominated and BB plumes
  contributed less than expected
• Dynamics played a large role in mixing plumes

China ffbf
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(No Transcript)
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Forecast Comparison with Flight Data
EKF assimilation of U,V, T and MOPITT CO in
CAM-Chem
Out of Seattle WA 04/17-05/01
OBS WITH MOPITT ASSIM (R0.72) W/O MOPITT ASSIM
(R0.63)
Out of Honolulu HI 04/17-05/01
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MOPITT CO Interannual variability

• 2006 appears to have an average amount of CO over
  the Pacific during April-May

Gabriele Pfister
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MOPITT Validation - INTEX-B

• Very few spirals were performed coincident with
  Terra overpasses, but many along-track profiles
  were roughly coincident
• Within 200 km and 13 hours
• DC-8 11
• C-130 16
• As seen previously, MOPITT shows a positive bias
  compared to in situ observations
• The MOPITT team continues to investigate the
  cause of the bias (instrument, a priori,
  retrievals, etc.) and hopes to reduce it in the
  next retrieval version

Colored points NOAA/GCD network profiles (P.
Novelli) C130 Teresa Campos, NCAR DC8 Glen
Sachse, NASA Langley