NASA GODDARD HOMEPAGE FOR TROPOSPHERIC
OZONE
NASA Goddard Space Flight Center
Code 613.3, Chemistry and Dynamics Branch
Investigators:
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TROPOSPHERIC OZONE DATA AND IMAGES FROM AURA OMI/MLS
As members of the Aura Ozone Monitoring Instrument (OMI) science
team we are developing several tropospheric ozone data products from
OMI in combination with Aura Microwave Limb Sounder (MLS). One of
these involves OMI-only "Cloud Slicing" measurements (discussed below)
to derive tropospheric and stratospheric ozone.
By combining OMI total column ozone measurements with MLS
stratospheric column ozone measurements, we are currently producing
global maps of OMI/MLS tropospheric ozone. Aura MLS stratospheric
ozone data were provided in collaboration with the Aura MLS team at
Jet Propulsion Laboratory, Pasadena, CA. All tropospheric ozone data
and images on this web site are considered preliminary. Development
of these data products is ongoing work.
NOTES:
(1) The tropospheric ozone on this webpage from combined Aura OMI and
MLS is an experimental science research data product and is not a
standard data product. Please revisit this website periodically for
updates to images and data.
(2) The OMI data and images from this webpage are from "collection 2"
processing and NOT "collection 3". The collection 3 data and images
from OMI are forthcoming at a later date.
(3) Below is the primary journal reference for the OMI/MLS
tropospheric ozone data:
Ziemke, J. R., S. Chandra, B. N. Duncan, L. Froidevaux, P. K. Bhartia,
P. F. Levelt, and J. W. Waters,
"Tropospheric ozone determined from Aura OMI and MLS: Evaluation
of measurements and comparison with the Global Modeling Initiative's
Chemical Transport Model", J. Geophys. Res., 111, D19303,
doi:10.1029/2006JD007089, 2006.
(PDF file, 5.0 Mb)
Sep04-Nov04 (left), Dec04-Feb05 (right):
Mar05-May05 (left), Jun05-Aug05 (right):
Sep05-Nov05 (left), Dec05-Feb06 (right):
Mar06-May06 (left), Jun06-Aug06 (right):
Sep06-Nov06:
Above: Near global maps of monthly-mean tropospheric column
ozone from combined Aura OMI and MLS measurements for September 2004
through January 2006. (CLICK EACH THUMBNAIL PICTURE TO OBTAIN A LARGE
JPEG IMAGE)
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OTHER PUBLIC DOMAIN DATA AND IMAGES, ETC. :
Monthly-mean maps (GIF images) of tropical tropospheric column
ozone (in Dobson Units) derived from the CCD method :
GRIDDED TROPICAL DATA:
Data for the above tropospheric column ozone images can be obtained
at this website. The data (see DATA DOCUMENTATION
) represent monthly-means with a resolution of 5 degrees latitude
by 5 degrees longitude and are printed in ASCII format for both TROPOSPHERIC and
STRATOSPHERIC column measurements.
Stratospheric column ozone to within a few Dobson Units in the
tropics is zonally homogeneous. For this reason the stratospheric
column ozone data file gives only one value for each latitude.
There is also an IDL
PROCEDURE provided to read these data tables. At current time
these CCD data files are developed from Nimbus 7 TOMS and Earth Probe
TOMS version 8 measurements. In the future, the new Aura OMI CCD data
will be appended to continue this long time-record data set.
PACIFIC AVERAGED DATA FOR 50S TO 60N:
Pacific averaged (120W-120E) monthly mean stratospheric and
tropospheric column ozone from TOMS measurements covering the
latitudeS 50S to 60N (5 degree latitude bands) can be obtained here.
The tabulated data were obtain using the CCD method. Measurements for
latitudes south of 50S and north of 60N are not included in the tables
because there are not enough suitable clouds for using the CCD method.
As with the above data tables, TOMS version 8 level-2 footprint
measurements were used to construct the data. There are two ASCII
tables, one for STRATOSPHERIC
column ozone and one for TROPOSPHERIC
column ozone. Time coverage extends from January 1979 through
December 2005. Two-sigma uncertainties in these monthly measurements
of both stratospheric and tropospheric column ozone are 5 DU. There
is an IDL PROCEDURE
provided to read these data tables. Note that in the tables the two
left-most numbers designate latitude ranges (maximum and minimum) for
the measurements. It is noted that the stratospheric column ozone
measurements outside the tropics from Earth Probe TOMS began having
problems in mid-2001. Stratospheric ozone began showing an erroneous
downward trend and a signature of a solar zenith angle dependent
calibration drift. Stratospheric data for years 2001-2005 are lower
than they should be, so that the variabilities in the measurements
should be evaluated with caution. Tropospheric ozone is not affected
directly by calibration drift (it's a differencing method) and
maintains reasonable numbers through year 2005.
SPECIAL NOTES:
All of the above data tables were determined from Nimbus 7 TOMS
(Jan79-Apr93) and Earth Probe TOMS (Aug96-Dec05) satellite
measurements. Following December 2005, Earth Probe TOMS no
longer provides data. In the future, the new Aura OMI ozone
measurements will be used to continue adding to these long time
records of stratospheric and tropospheric column ozone.
Below is the primary journal reference for the CCD data and methodology:
Ziemke, J. R., S. Chandra, and P. K. Bhartia,
"Two new methods for deriving tropospheric column ozone from TOMS
measurements: The assimilated UARS MLS/HALOE and convective-cloud
differential techniques",
J. Geophys. Res., 103, 22,115-22,127, 1998.
(PDF file, 18.1 Mb)
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REFEREED PUBLICATIONS ON TROPOSPHERIC OZONE:
Ziemke, J. R., S, Chandra, S., M. R. Schoeberl, L. Froidevaux,
W. G. Read, P. F. Levelt, and P. K. Bhartia,
"Intra-seasonal variability in tropospheric ozone and water vapor in
the tropics", Geophys. Res. Lett., 34, L17804,
doi:10.1029/2007GL030965, 2007.
(PDF file, 0.47 Mb)
Chandra, S., J. R. Ziemke, M. R. Schoeberl, L. Froidevaux, W. G. Read,
P. F. Levelt, and P. K. Bhartia,
"Effects of the 2004 El Nino on tropospheric ozone and water vapor",
Geophys. Res. Lett., 34, L06802, doi:10.1029/2006GL028779, 2007.
(PDF file, 0.3 Mb)
Ziemke, J. R., S. Chandra, B. N. Duncan, L. Froidevaux, P. K. Bhartia,
P. F. Levelt, and J. W. Waters,
"Tropospheric ozone determined from Aura OMI and MLS: Evaluation
of measurements and comparison with the Global Modeling Initiative's
Chemical Transport Model", J. Geophys. Res., 111, D19303,
doi:10.1029/2006JD007089, 2006.
(PDF file, 5.0 Mb)
Tie, X., S. Chandra, J. R. Ziemke, C. Granier, and G. P. Brasseur,
"Satellite measurements of tropospheric column O3 and NO2 in eastern
and southeastern Asia: Comparison with a global model (MOZART-2)",
J. Atmos. Chem., doi:10.1007/s10874-006-9045-7, 2006.
(PDF file, 8.8 Mb)
Ziemke, J. R., S. Chandra, and P. K. Bhartia,
"A 25-year data record of atmospheric ozone in the Pacific from TOMS
Cloud Slicing: Implications for ozone trends in the stratosphere and
troposphere", J. Geophys. Res., 110, D15105, doi:10.1029/2004JD005687,
2005.
(PDF file, 1.4 Mb)
Chandra, S., J. R. Ziemke, X. Tie, and G. Brasseur,
"Elevated ozone in the troposphere over the Atlantic and Pacific Oceans
in the northern hemisphere", Geophys. Res. Lett., 31, L23102,
doi:10.1029/2004GL020821, 2004.
(PDF file, 0.6 Mb)
Ziemke, J. R., and S. Chandra,
"A Madden-Julian Oscillation in tropospheric ozone", Geophys. Res.
Lett., 30(23), 2182, doi:10.1029/2003GL018523, 2003.
(PDF file, 0.8 Mb)
Ahn, C., J. R. Ziemke, S. Chandra, and P. K. Bhartia,
"Derivation of tropospheric column ozone from EPTOMS/GOES co-located
data sets using the Cloud Slicing technique", J. Atmos. Solar Terr.
Phys., 65(10), 1127-1137, 2003.
(PDF file, 1.1 Mb)
Ziemke J. R., S. Chandra, and P. K. Bhartia,
"Upper tropospheric ozone derived from the Cloud Slicing technique:
Implications for large-scale convection",
J. Geophys. Res., 108(D13),
4390, doi:10.1029/2002JD002919, 2003.
(PDF file, 2.6 Mb)
Chandra, S., J. R. Ziemke, and R. V. Martin,
"Tropospheric ozone at tropical and middle latitudes derived from
TOMS/MLS residual: Comparison with a global model",
J. Geophys. Res.,
108(D9), 4291, doi:10.1029/2002JD002912, 2003.
(PDF file, 6.4 Mb)
Ziemke, J. R., and S. Chandra,
"La Nina and El Nino induced variabilities of ozone in the tropical
lower atmosphere during 1970-2001",
Geophys. Res. Lett., 30(3), 1142,
doi:10.1029/2002GL016387, 2003.
(PDF file, 5.3 Mb)
Chandra, S., J. R. Ziemke, P. K. Bhartia, and R. V. Martin,
"Tropical tropospheric ozone: Implications for dynamics and biomass
burning", J. Geophys. Res., 107(D14),
doi:10.1029/2001JD00044, 2002.
(PDF file, 2.0 Mb)
Ziemke, J. R., S. Chandra, and P. K. Bhartia,
"Cloud slicing: A new technique to derive upper tropospheric ozone
from satellite measurements",
J. Geophys. Res., 106, 9853-9867, 2001.
(PDF file, 4.3 Mb)
Martin, R. V., D. J. Jacob, J. A. Logan, J. R. Ziemke, and R. Washington,
"Detection of lightning influence on tropical tropospheric ozone using
empirical orthogonal functions",
Geophys. Res. Lett., 27, 1639-1642,2000.
(PDF file, 0.2 Mb)
Ziemke, J. R., S. Chandra, and P. K. Bhartia,
"A new NASA data product: Tropospheric and stratospheric column ozone
in the tropics derived from TOMS measurements",
Bull. Amer. Meteorol.
Soc., 81, 580-583, 2000.
(PDF file, 0.4 Mb)
Ziemke, J. R., and S. Chandra,
"Seasonal and interannual variabilities in tropical tropospheric ozone"
,
J. Geophys. Res., 104, 21,425-21,442, 1999.
(PDF file, 23.4 Mb)
Chandra S., J. R. Ziemke, and R. W. Stewart,
"An 11-year solar-cycle in tropospheric ozone from TOMS measurements"
,
Geophys. Res. Lett., 26, 185-188, 1999.
(PDF file, 1.7 Mb)
Ziemke, J. R., S. Chandra, and P. K. Bhartia,
"Two new methods for deriving tropospheric column ozone from TOMS
measurements: The assimilated UARS MLS/HALOE and convective-cloud
differential techniques",
J. Geophys. Res., 103, 22,115-22,127, 1998.
(PDF file, 18.1 Mb)
Ziemke, J. R., and S. Chandra,
"On tropospheric ozone and the tropical wave 1 in total ozone",
in Atmospheric
ozone, Vol. 1, edited by R. D. Bojkov and
G. Visconti, pp. 447-450, 1998.
(PDF file, 0.6 Mb)
Chandra, S., J. R. Ziemke, W. Min, and W. G. Read,
"Effects of 1997-1998 El Nino on tropospheric ozone and water vapor"
,
Geophys. Res. Lett., 25, 3867-3870, 1998.
(PDF file, 22.1 Mb)
Ziemke, J. R., and S. Chandra,
"Comment on 'Tropospheric ozone derived from TOMS/SBUV measurements
during TRACE A' by J. Fishman et al.", J. Geophys. Res., 103,
13,903-13,906, 1998.
(PDF file, 1.2 Mb)
Ziemke, J. R., S. Chandra, A. M. Thompson, and D. P. McNamara,
"Zonal asymmetries in southern hemisphere column ozone: Implications of
biomass burning", J. Geophys. Res., 101, 14,421-14,427, 1996.
(PDF file, 25.1 Mb)
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REFEREED PUBLICATIONS (IN REVIEW) ON TROPOSPHERIC OZONE:
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TREND ANALYSIS SOFTWARE, ETC.:
MULTIPLE LINEAR REGRESSION SOURCE CODES FOR
TREND ANALYSIS AND GENERAL SCIENCE APPLICATIONS (both Fortran and IDL
software - includes example programs). The trend analysis code
originated from Ziemke et al. [1997]
(PDF file, 4.8 Mb) which used a Monte Carlo statistical approach.
The multi-variate statistics built into the trend code can be turned
off and replaced by a Monte Carlo method by adding random noise to the
independent proxies.
FORTRAN CODE for solving general N X N linear
system problems (i.e.,solves AX=B using Gauss-Jordan method).
FORTRAN CODE for numerically solving ordinary
differential equations (coupled Runge-Kutta method). This program
shows one example of a 3rd-order ODE and prints the results to an
ASCII table which can be plotted using an IDL
PLOTTING PROGRAM. The IDL program generates a postscript IMAGE.
FORTRAN CODE for Empirical Orthogonal
Function (EOF) analysis of data.
FORTRAN CODE for Fast Fourier
Transform analysis of data. The first step of Fourier analysis is to
determine prime number factorization of the time series length (Here
is a FORTRAN CODE for providing prime
number factorization). Here is also a FORTRAN CODE
for listing prime numbers.
Short glossary of commonly-used terms in Atmospheric Science
(all pages are GIF IMAGES): PAGE1,
PAGE2, PAGE3,
PAGE4, PAGE5,
PAGE6.
SHORT GLOSSARY (text file) of
commonly-used terms in Atmospheric Science from the University
of Illinois at Urbana-Champaign.
FIGURE (GIF IMAGE): What is a Dobson
Unit (DU)?
FIGURE (GIF IMAGE): How is Column
Ozone Computed?
SPACE TIME HARMONIC DECOMPOSITION (GIF
IMAGE) for data with one temporal and one spatial (longitude)
variable.
COMPLETE LIST OF OUR
PUBLICATIONS RELATED TO TROPOSPHERIC OZONE.
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USING CLOUDS IN THE ATMOSPHERE TO MEASURE OZONE: "CLOUD SLICING":
"Cloud Slicing" refers to a method developed within NASA
Goddard Code 613.3 to derive ozone vertical profile information in the
troposphere given coincident satellite measurements of both cloud-top
pressure and above-cloud column ozone. Above-cloud column ozone is
measured from total ozone mapping spectrometer (TOMS) measurements.
Because the TOMS instrument measures backscattered ultraviolet (UV)
wavelength radiation, it cannot detect ozone lying below dense water
vapor clouds. This opaque property of clouds can be used directly in
conjunction with co-located cloud-top pressure data to derive ozone
profile information in the troposphere.
The derivation of ozone volume mixing ratio begins by first
plotting above-cloud column ozone (in Dobson Units, "DU") versus
cloud-top pressure (in hPa, same as "millibar"). Ozone
volume mixing ratio (in parts per million by unit volume, ppmv) is
then determined by multiplying the slope of the curve by the number
1.27. There are two algorithms currently under development, one for
high resolution satellite footprint measurements, and one for low
resolution measurements. For HIGH RESOLUTION
CLOUD SLICING the satellite field of view is small enough to
provide Cloud Slicing analysis of individual clouds. However current
TOMS measurements have a large field of view (around 100 km on
average) which is usually much larger than the clouds being used for
Cloud Slicing. The result is not enough clouds and too much clear sky
within the scene. Future satellite ozone instruments will have much
smaller footprint measurements than TOMS and may allow extensive
applications of high resolution Cloud Slicing.
Although it is possible to find large enough cloud systems
for attempting high resolution Cloud Slicing with TOMS measurements,
our primary method uses a STATISTICAL ENSEMBLE
CLOUD SLICING approach for deriving tropospheric ozone profile
information in the upper troposphere. The analyses were carried
out in the tropics for monthly ensembles with 5 degree by 5 degree
horizontal resolution. To reduce the number of partially cloudy
footprint scenes only TOMS ozone measurements with reflectivity
R greater than 0.6 were used in the Cloud Slicing analyses. Scenes
with R>0.6 coincide with 100% cloud fraction and generally
middle to upper tropospheric cloud tops. In our first trial study
of Cloud Slicing we combined Nimbus 7 version 7 TOMS ozone with
co-located Nimbus 7 temperature humidity infrared radiometer (THIR)
cloud-top pressure for the time period 1979-1984 [J. R. Ziemke,
S. Chandra, and P. K. Bhartia, J. Geophys. Res., 9853-9867, 2001].
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CONVECTIVE CLOUD DIFFERENTIAL (CCD) METHOD:
Monthly averaged tropospheric column ozone (TCO) and stratospheric
column ozone (SCO) data are derived in the tropics for January
1979-present using the convective cloud differential (CCD) method of
Ziemke et al. (J. Geophys. Res., 1998). In the CCD method total
column ozone is derived from low reflectivity (R<0.2) measurements and
SCO follows from nearby column ozone measurements taken above the tops
of tropopause level clouds under conditions of high reflectivity
(R>0.9)
(SEE SCHEMATIC). Above-cloud column amounts (in 5 degree by 5
degree bins) are first evaluated in the Pacific region where
tropopause/near-tropopause level clouds are common. SCO is then
derived for every 5 degree latitude band for 120E eastward to 120W
using only the lowest values of above-cloud column amounts (it is the
average of these lowest column amounts in each 5 degree by 5 degree
bin over the Pacific that becomes our estimated SCO). These SCO
values from the Pacific region are then assumed to represent SCO at
all other longitudes in a given latitude band. This assumption is
based on the zonal characteristics of tropical SCO as inferred from
Stratospheric Aerosols and Gas Experiment (SAGE) ozone, and as
inferred from Upper Atmosphere Research Satellite (UARS) microwave
limb sounder (MLS) and halogen occultation experiment (HALOE)
ozone.
The basic assumptions of the CCD method as applied to the tropics
are
(1) The high-reflectivity (R > 0.9) physical cloud tops over the
Pacific region lie near the tropopause, or in general that the ozone
amount lying between the tropopause and the UV-measured effective
cloud-top is negligible (<1-2 DU) for the lowest values of above-cloud
column ozone selected.
(2) Zonal (i.e., west to east) variability of stratospheric column
ozone is negligible in the low-latitude tropics. This allows SCO as
measured from the Pacific to represent SCO at all other longitudes
along a given latitude band.
Although the CCD data downloadable from this website represent
monthly ensembles, the assumption of zonal invariability to
first-order approximation is valid even for daily measurementes. For
daily measurements most zonal variability in SCO in the tropics is
caused by episodic dynamical waves of only a few Dobson Units
variability. These dynamical waves in SCO include Kelvin waves
[Ziemke and Stanford, 1994]
(PDF file, 1.4 Mb) and also mixed Rossby-gravity waves, equatorial
Rossby waves, etc. [Ziemke and Stanford, 1994]
(PDF file, 5.7 Mb).
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CONTACT INVESTIGATOR:
Dr. Jerry R. Ziemke
NASA Goddard
Space Flight Center
Code 613.3, Chemistry and
Dynamics Branch
Greenbelt, Maryland, 20771
Office phone: 301-614-6034
Office Fax: 301-614-5903
Email: ziemke@jwocky.gsfc.nasa.gov
Affiliation:
UMBC GEST (non-NASA website), Baltimore,
Maryland
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Web Curator: Dr. Jerry R. Ziemke (UMBC GEST, and NASA GSFC
Code 613.3)
Responsible NASA official: Dr. P. K. Bhartia, Atmospheric
Chemistry and Dynamics Branch, NASA GSFC Code 613.3
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