sciamachy co, ch4, n2o scientific data products algorithms: … · 2018-05-15 · atmospheric...

Atmospheric Chemistry Validation of ENVISAT – ESRIN - 3-7 May 2004

SCIAMACHY CO, CH4, N2Oscientific data products

algorithms:WFM-DOAS v0.4 (UBremen)

&IMLM (SRON)

comparisons with GB(FT)IR measurements

Martine De MazièreBelgian Institute for Space Aeronomy


H. Schrijver, I. AbenSRON, The Netherlands

M. Buchwitz, R. De Beek, & J. Notholt, T. Warneke

Institute of Environmental Physics, University of Bremen, GermanyT. Blumenstock, A. Griesfeller

Forschungszentrum Karlsruhe, IMK, GermanyE. Mahieu, P. Demoulin,, P. Duchatelet

Institut d'Astrophysique et de Géophysique, University of Liège, BelgiumJ. Mellqvist, A. Strandberg

Chalmers University of Technology, SwedenA. Schulz

Alfred Wegener Institute for Polar and Marine Research (AWI), GermanyR. Sussmann

Forschungszentrum Karlsruhe, IFU, GermanyH. Fast, R. L. Mittermeier & K. Strong

Meteorological Service of Canada (MSC) & University of Toronto, Canada S. Wood, D. Smale

National Institute for Water and Air Research (NIWA), New-ZealandD. Griffith, N. Jones

University of Wollongong, AustraliaC. Rinsland

NASA Langley Research Center, USAD.Ionov

University of St. Petersburg, Russia

Coworkers at BIRA-IASBContributing PI’s

M. De MazièreT. Coosemans

J. GranvilleP. GérardT. Jacobs

K. Janssens J.C. LambertC. Vigouroux


Correlative dataset

Arrival Heights

Lauder

Wollongong

Izaña

Jungfraujoch& Zugspitze

HarestuaKiruna

Ny Alesund

Egbert

Kitt Peak

Mauna Loa

St Petersburg

Zvenigorod

Obninsk

AO ID126

Station name Lat N Lon E

Alt asl (m)

Egbert 44.23 -79.78 251Ny Alesund 78.91 11.88 20Kiruna 67.84 20.41 419Harestua 60.22 10.75 580Zugspitze 47.5 11.1 2964Jungfraujoch 46.55 7.98 3580Toronto 43.7 -79.4 174Kitt Peak 31.9 -111.6 2090Izana 28.3 -16.48 2367Wollongong -34.4 150.9 30Lauder -45.05 169.7 370Arrival Heights -77.83 166.7 190

CO from cloud-free pixels

(∆CO < 60%)Ship Cruise (AWI- Uni Bremen) Jan 25 – Feb 9, 2003

5 days of overlapping data


T. Warneke et al.

Cruise Jan/Feb 2003

IUP Bremen

Black - Ship trackGreen - trajectories (850 hPa) Blue - closest WFM-DOAS-dataRed - fires (from MODIS)

High CO from biomass burning


Comparison caveats(FT)IR is the only GB technique to provide correlative total column data – but

number of GB measurements is limited - cf. need clear sky

Period of SCIA data not optimised for best overlap with GB data;Only retrievals for cloud-free pixels are sufficiently reliable

A number of intercomparisons must be interpreted with care

Comparisons between total column data at high altitude stations;⇓

adopted approach: to use altitude-normalised data which is a better compromise for CH4 and N2O than for CO

- still in mountainous regions, pixels do not represent uniform elevationOr

to compare ‘anomalies’ wrt an ensemble average (e.g., for CO at Zugspitze)

Comparisons at stations situated near the coast (e.g. Lauder) - cf colocated pixels may be over sea

Verify whether SCIA data are over sea or have a large retrieval error


Altitude issueexample CO at Jungfraujoch – GB FTIR versus SCIA WFM-DOAS

Not normalised for altitude 3580 m normalised for altitude

+ GB FTIRX SCIA O SCIA cloud-free

M. De Mazière et al.Next comparisons with GB FTIR network adopt altitude-normalised data


Retrieval error versus ‘albedo’IMLM / SRON WFM-DOAS / UBremen

Error_CO < 60%Error_N2O < 30%Error_CH4 < 7%

Error_CO < 9E17 molec/cm2Error_CH4 < 1E18molec/cm2

2.5%N2O

0.5%CH4

2.5%COPrecision of GB FTIR data Accuracy of GB FTIR

2.5 %N2O10 %CH47 %CO

2 - 3 %N2O1 - 3 %CH42 - 4 %CO


COCO


0.E+00

1.E+18

2.E+18

3.E+18

4.E+18

5.E+18

6.E+18

7.E+18

-60 -40 -20 0 20 40 60

latitude

CO

(mol

ecul

es/c

m2 )

SCIA seaSCIA landFTS ship

Cruise FTIR data

Conditions of comparisons with WFM-DOAS data:

Same day ; +/- 1.5°lat ; closest lon; cloud-free SCIA pixel ; error for CO over sea < 60%

T. Warneke et al.

0

1

2

3

4

5

6

7

8

9

10

30/06/02 20/07/02 09/08/02 29/08/02 18/09/02 08/10/02 28/10/02 17/11/02 07/12/02 27/12/02

CO

VC

D, 1

018 m

ol/c

m2

GB

SCIA scientific*

0

1

2

3

4

5

6

7

8

9

10

30/06/02 20/07/02 09/08/02 29/08/02 18/09/02 08/10/02 28/10/02 17/11/02 07/12/02 27/12/02

CO

VC

D, 1

018 m

ol/c

m2

GB

SCIA scientific*

0

1

2

3

4

5

6

7

8

9

10

30/06/02 20/07/02 09/08/02 29/08/02 18/09/02 08/10/02 28/10/02 17/11/02 07/12/02 27/12/02

CO

VC

D, 1

018 m

ol/c

m2

GB

SCIA scientific*− GB● SCIA

Russian grating spectrometer data

Conditions of comparisons with IMLM (SRON) data:w/i 12 hours; w/i 1000 km radius; all SCIA pixels D. Ionov et al.


CO at Zugspitze: GB FTIR versus SCIA – WFM-DOASin terms of ‘anomalies’

-7.00

-5.00

-3.00

-1.00

1.00

3.00

5.00

7.00

9.00

Dez. 02 Feb. 03 Apr. 03 Jul. 03 Sep. 03 Nov. 03

Date

Col

umn

anom

aly

Zugspitze FTIR: Anomaly of pressurecorrected CO columns, individualmeasurements, 20 min integration time

SCIA_WFMD_v0.4: CO/O2 columnsanomaly, individual pixels from 500-kmradius around Zugspitze; includes cloudcontaminated pixels (69 %)

SCIA_WFMD_v0.4: CO/O2 columnsanomaly, individual pixels from 500-kmradius around Zugspitze; cloud flaggedpixels removed

IMK-IFUGarmisch


Error bars: +/- 1 sigma

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

Dez. 02 Feb. 03 Apr. 03 Jul. 03 Sep. 03 Nov. 03 Feb. 04

Date

Col

umn

anom

aly

Zugspitze FTIR CO column anomaly: daily means

SCIA_WFMD_v0.4 CO/O2 column anomaly: average of allpixels within 500 km around Zugspitze for daily overpass;cloud falgged pixels removed

Polynomial 3rd order

Polynomial 3rd order

IMK-IFUGarmisch

Are observed variabilities consistent ?


CO globally – FTIR network versus WFM-DOAS

AO ID126 FTIR network

relative differences SCIA-FTIR (%)

Jan 2003 Nov 2003

Error_based selection



Conditions of comparisons with SCIA data:

Open symbols:Same day; +/- 2.5°lat and +/- 10° lon; cloud-free SCIA pixel ;

Yellow filled symbols:Same day; +/- 2.5°lat and +/- 5° lon; cloud-free SCIA pixel ; altitude w/i +/- 250 m

altitude-normalised data

M. De Mazière et al.


CO globally – FTIR network versus IMLM

July 2002 Mid-April 2003




Conditions of comparisons with SCIA data: Open symbols:Same day; +/- 2.5°lat and +/- 10° lon; cloud-free SCIA pixel ;





CHCH44


1000

1200

1400

1600

1800

2000

2200

2400

-60 -40 -20 0 20 40 60latitude

CH

4 (pp

bv)

SCIA seaSCIA landFTS shipNOAA/CMDL

Cruise FTIR data


Same day ; +/- 1.5°lat ; closest lon; cloud-free SCIA pixel ; error for CH4 over sea < 7%T. Warneke et al.

CH4 cruise data scaled by 0.9 to agree with NOAA/CMDL data


CH4 globally – FTIR network versus WFM-DOAS

Jan 2003 Mid-Sept 2003


relative differences SCIA-FTIR (%)AO ID126

FTIR network







CH4 globally – FTIR network versus IMLM

Mid-April 2003Jan 2003


relative differences SCIA-FTIR (%)AO ID126

FTIR network







NN22OO


0.0E+00

3.0E+18

6.0E+18

9.0E+18

1.2E+19

1.5E+19

1.8E+19

-60 -40 -20 0 20 40 60latitude

N2O

(mol

ecul

es/c

m2 )

sealandFTIR

Cruise FTIR data


Same day ; +/- 1.5°lat ; closest lon; cloud-free SCIA pixel ; error for N2O over sea< 30%T. Warneke et al.


N2O globally – FTIR network versus WFM-DOAS

Jan 2003 Mid-Sept 2003










Conclusions

Late availability of data has not allowed many nor detailed analyses

Conclusions from available limited (in number and depth) intercomparisons:

Scientific data products are a large improvement upon NRT products and demonstrate the capability of SCIAMACHY to detect variability in CO, CH4 and N2O

Actual performances of wfm-doas and IMLM algorithms are similar –Observed relative differences with GB data (SCIA-GB) are within

-50 → +50 % for CO – overestimation by WFM-DOAS? underestimation by IMLM ? TBC-40 → +40 % for CH4-20 → +60% for N2O (wfm-doas only)

Conservative estimates! Conditions for comparisons need improvement; more statistics are welcome


The end for nowThe end for now

sciamachy co, ch4, n2o scientific data products algorithms: … · 2018-05-15 · atmospheric...

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