inverse modeling of north american co sources during the summer 2004 (icartt)

Inverse modeling of North American CO sources Inverse modeling of North American CO sources during the summer 2004 (ICARTT)during the summer 2004 (ICARTT)

S. Turquety, D. J. Jacob, R. C. Hudman, J. A. Logan, R. M. Yevich, F. Y. Leung, R. M. S. Turquety, D. J. Jacob, R. C. Hudman, J. A. Logan, R. M. Yevich, F. Y. Leung, R. M. Yantosca, C. L. Heald, L. K. Emmons, D. P. Edwards, Yantosca, C. L. Heald, L. K. Emmons, D. P. Edwards,

and the INTEX Science Teamand the INTEX Science Team

1. Anthropogenic emissions: • EPA emission inventories and trends: Uncertainty on the CO emissions estimated to ~ 40% by comparison with in situ observations [Parrish, in preparation]• Global inverse modeling analyses : North American FF/BF emissions of CO vary by up to ~ 70% • ICARTT observations: model seem to strongly overestimate CO in the PBL

2. Biomass burning emissions during the summer 2004 : • 2004: worst fire season in Alaska on record!• Burning in boreal forests of Canada or Siberia can have a large impact on CO on

an hemispheric scale, and on air quality in the US in particular • Burning in boreal regions expected to significantly increase as a result of climate

change

Solène Turquety – GEOS-CHEM Meeting April 5, 2005

(R. Hudman)


Alaska:

• > 2.6 million hectares burned

• > 8 x 10-year average

Canada:

• 15 x average area burned in Yukon Territory (60% of national total)

• 6 x average in British Columbia

US National Interagency Coordination Center (NICC)

Canadian Interagency Forest Fire Center (CIFFC)

Bottom-up inventory of the biomass burning emissions in North America Bottom-up inventory of the biomass burning emissions in North America during the summer 2004during the summer 2004

Biomass burning 2004: Strong signature during ICARTTBiomass burning 2004: Strong signature during ICARTT


Daily reports of the area burned from the NIFC


Emissions CO 2004Emissions / unit area

A x 60%

[W.M. Hao, FSL, Personal comm.]

Derive emissions for 10 species, with 1x1 horizontal resolution: NOx, CO, lumped >= C4 alkanes, lumped >= C3 alkenes, acetone, methyl ethyl ketone, acetaldehyde, propane, formaldehyde, and ethane.

MODIS hotspots



Total emissions North America June 1st – August 31st = 10.3 Tg CO

Alaska : 5.7 Tg CO 3 x climatology Logan and Yevich

Canada: 4.5 Tg CO 0.9 x climatology ; Yukon territory: 2.3 Tg CO 4.4 x clim.


Alaska

Canada

Day since June 1st, 2004

2004

Logan and Yevich

To

tal

emis

sio

ns

CO

(T

g)


(MOPITT – Model)/MOPITT

MOPITT Total CO – summer 2004 GEOS-CHEM Total CO x MOPITT AK

On average: Underestimate emissions by ~ 25% on average

Area burned? Uncertainty reports…

Emissions / unit area (fuel loads) ?

Injection heights?


Importance of injection heights for the 2004 Alaskan-Yukon firesImportance of injection heights for the 2004 Alaskan-Yukon fires


Use TOMS AI as an indicator of the altitude of the aerosol layer:

Sensitivity as altitude of the aerosol layer (low sensitivity to the PBL)



Pyro-convective cloud from aircraft – June 27, 2004http://www.cpi.com/remsensing/midatm/smoke.html


To

tal

CO

em

iss

ion

sM

ax

imu

m T

OM

S A

I

Alaska – Yukon fires summer 2004

http://www.cpi.com/remsensing/midatm/smoke.html

Biomass burning plume sampled by the DC-8 on flight # 9 (July 18th)

GEOS-CHEM NRTObs. G. W. Sachse


Biomass burning 2004: Strong signature during ICARTTBiomass burning 2004: Strong signature during ICARTT

GEOS-CHEM NRT



850hPa700hPa

500hPa

Compute 5-days trajectories w/ GEOS-4 from TOMS AI to calculate exposure to aerosols (K. Pickering, GSFC, http://croc.gsfc.nasa.gov/intex/)



What are the implications for CO inversion?

MOPITT Total CO July 17-19, 2004 GEOS-CHEM Total CO x MOPITT AK July 17-19, 2004


55 %

40 %

400mb

PBL

Vertical distribution

5 % Upper troposphere

Free troposphere

Boundary layer

200mb



What are the implications for CO inversion?

GEOS-CHEM BB CO 100 % BL x MOPITT AK

GEOS-CHEM BB CO 100 % UT x MOPITT AK

GEOS-CHEM BB CO 100 % FT x MOPITT AK



What is the implications for long range transport?

MOPITT Total CO July 22-24, 2004 GEOS-CHEM Total CO x MOPITT AK July 22-24, 2004




What are the implications for long range transport?

GEOS-CHEM BB CO 100 % BL x MOPITT AK

GEOS-CHEM BB CO 100 % UT x MOPITT AK

GEOS-CHEM BB CO 100 % FT x MOPITT AK

Ongoing and future workOngoing and future work

1. Using satellite observations to constrain the daily North American biomass burning emissions during the summer 2004

• Magnitude? • Injection height?

GEOS-CHEM NRT July 18

A priori sourcesGEOS-CHEM


Inversion

A posteriori sources

AIRS CO for July 18

+ TOMS AI? MISR ?


Inversion(?)

MOPITT CO for July 18

xax

Strong variability => daily inversion


2. Inverse modeling of North American anthropogenic emissions of CO using aircraft and satellite measurements

GEOS-CHEM NRT

A priori sourcesGEOS-CHEM


AIRS CO


Inversion(?)

MOPITT CO

xxa



…

obsy

εKxy x

y

x

yK

MOPITT observation Model simulation, with MOPITT AK applied

Linear approximation:

my

K provides the sensitivity of the measurement to the source of interest.

Calculated using a tagged CO simulation

εxy )f(Observation vector:

State vector: CO sourcesObservation error

with





To

tal

CO

em

iss

ion

sM

ax

imu

m T

OM

S A

I

Alaska – Yukon fires summer 2004

Strong daily variability

Daily inversion

Two main signals for the fires:

• Alaska – Yukon

• Northwest territory

)(1

ˆ aaaa xKySKSKKSxx

TT

Inverse modeling of North American CO emissionsInverse modeling of North American CO emissionsconcept and methodconcept and method

Maximum a posteriori (MAP) solution [Rodgers, 2000]

i.e. solution which minimizes cost function:

)(1)()(1)()J( aaa xxSxxxKySxKyx TT

Difference between observation and simulation

Difference between true state and a priori knowledge

111ˆ

aSKSKS T(MOPITT – MODEL)

A priori state vector Gain matrix

Observation error A priori error

Sequential inversion: observations considered sequentially

Inverse modeling of North American CO emissionsInverse modeling of North American CO emissionsKalman SmootherKalman Smoother

timet = Tt = 0 t = 1 t

Forward Kalman filter

Backward Kalman filter

Combination forward + backward = Kalman smoother

x’(0)^ x’(1)^ x’(T)^

x’’(T)^x’’(1)^x’’(0)^

x’(t)^

x’’(t)^

yobs(0) yobs(1) yobs(T)

x’’ ^

x’ ^

x

A priori

A priori

Update a priori

Update a priori

tttt ξxΜx )1(

tttt εxy )(f εtKtxt t

Ttttt ξSΜSΜS 1

ˆInversion of time dependant emissions: Kalman filter (forward)

inverse modeling of north american co sources during the summer 2004 (icartt)

Documents

total emissions north

underestimate emissions

x average

emissions unit areaa

north american ffbf

particular burning

x mopitt akon average

average area