Forward/Inverse Atmospheric Modelling: Recent Results and

Future Plans

Martyn Chipperfield, Manuel GloorUniversity of Leeds

NCEO meeting, University of Sheffield, 28th and 29st February 2012

Paul PalmerUniversity of Edinburgh

Talk Layout

• Example Leeds forward/inverse model results

• Edinburgh plans (Paul Palmer)

• Additional science slides (Manuel Gloor, Leeds)

• Summary

TOMCAT CH4 forward simulations – Transcom Results

Annual mean CH4 comparisons for six emission scenarios against NOAA surface flask data, 1988-2008.

Average monthly mean CH4 comparisons for six emission scenarios against NOAA surface flask data, 2000-2006.

TOMCAT CH4 forward simulations – Transcom Results

TOMCAT Adjoint Modelling – ALT station sensitivities

sensitivity CTL sensitivity INV sensitivity

Adjoint transport carried out using an initial value of 1 at Alert, Canada to find the sensitivity (LH plots)

This sensitivity is then multiplied by the emission rate for CTL (Centre plots) and INV emission (RH plots) inventories

This gives an ‘emission sensitivity’ for the ALT station, indicating the emission regions which are influencing the tracer concentration at the station

TransCom CH4 emissions

NH Wetland areas treated individually

1. Alaska and Canada (>60N) (AL_CAN)

2. West Siberian Plain (WSP)3. Eastern Siberia (>60N) (E_SIB)

(Below) Total CH4 emissions for three TransCom emission inventories in wetland regions

TOMCAT 4D-Var inversion results

One year inversion carried out (2008), assimilating eight-day mean data from six Arctic stations.

Representative results show relatively small changes in NH winter, but large reductions in wetland areas during April – October

Wilson et al (in prep), 2012

More TOMCAT 4D-Var inversion results

(Left) Cost function decrease over three iterations of 4D-Var minimisation, split into contributions from observations (CF_O) and background (CF_B)

(Below) Total CH4 emissions for three wetland areas. TOMCAT inversion has decreased emissions in line with INV and VISIT in Eastern Siberia and Alaska/Canada regions

Effect of emission changes

There is a marked improvement in RMSE between model and observations at the stations from which data has been assimilated, especially during NH summer months

U. Ed. Past NCEO T3 CH4 activities• Developed CH4

simulation ready for EO• Used EO data to develop

wetland emissions [Bloom et al, 2010]

• Developed EnKF for CH4 source/sink estimation

• Extensively evaluated model [Fraser et al, 2011]

• Established links with GOSAT teamCore

framework

U. Ed. Ongoing NCEO T3 CH4 activities• TransCom (Patra et al, 2011) and GCP (Kirschke et al, 2011)• Flux estimates: improve geographical and sector breakdown.• GOSAT collaboration with U. Leicester (Parker et al, 2011)

SHN

H

• GEOS-Chem to use GEOS v5 met. data (0.25ox0.3125o)• Data: GOSAT, IASI, Sentinel-5P + any new national

missions; exploiting correlations with CO• Major focus:

U. Ed. Future NCEO CH4 activities

GEO

S-Ch

em/E

nKF JU

LES/HadG

EM2

•Compare bottom-up/top-down wetland emissions•Help inform JULES development•Co-join two models•Develop inverse problem (parameter estimation?)

EO data

What could be focus of research? Could include:

GHG flux estimation using inversions (and new measurements programs like AMAZONICA or OCO2?)

Land surface observation using remote sensing – e.g. GRACE or NDVI

Land surface – climate interaction modelling using JULES ?

Seneviratne et al. 2010

Links to Leeds Amazon Work

Regions with strong soil-moisture temperature coupling

Currently: not much predictive capability e.g. in tropics

Amazon river discharge at Obidos (drains nearly80 % of Amazon basin)

(data from ABA, Brazil govt. hydro-logy measurements, gap filling by Callède et al.)

- Overall an upward trend in river discharge- extremes increase – dry season drier, wet season wetter

How will land vegetation respond ?

Peak

Mean

Minimum

AMAZONICA - biweekly Greenhouse Gas DataDec. 2009 onwards for next 4 years (L. Gatti, Sao Paulo, M. Gloor, Leeds, H. Rocha, Sao Paulo, J. Miller NOAA, Boulder)

FCO2 (CO2

site CO2backgrd )dz

z0

4km

tSanta Rem tcoast

Simple Analysis Through Back Trajectories

Tabatinga Santarém

Rio Branco Alta Floresta

In 2010: Amazon weak net carbon source (~0.2PgC yr-1)

What could be focus of research:

GHG flux estimation using inversions (and new measurements programs like AMAZONICA or OCO2?)

Land surface observation using remote sensing – e.g. GRACE or NDVI

Land surface – climate interaction modelling using JULES ?

Possibly:Observe and understand ongoing trends of the land-vegetation climate coupled system in those regions which are sensitive

Summary

Tools:• Forward atmospheric CH4/CO2/CO (+ full chem) chemical transport models operational and tested• Inverse schemes EnKF and 4D-var operational

Plans:• Assimilate existing/new satellite datasets (GOSAT, IASI, Sentinel 5-P)• Test top down/bottom up emission estimates• Close collaboration with JULES team (CEH)

Scientifically:• Arctic wetlands• AMAZONICA / vegetation-atmosphere interactions• Others…

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