FTS Measurements for Constraining the Australian Carbon Cycle

Nicholas Deutscher1,2, Rachel Law1, David Griffith2 and Glenn Bryant2

Outline: • My PhD Plan

1CSIRO Atmospheric Research, Aspendale, Victoria 31952Atmospheric Chemistry Research Group, Department of Chemistry, University of Wollongong, Wollongong, NSW, 2522

My PhD Project

Aim: to better understand the Australian carbon cycle; and to provide constraints to estimates of Australian carbon

fluxes.

How? – Using: FTS atmospheric trace gas measurements; and Inverse atmospheric modelling

Background – Why Australia?

Well…

Also:– Unique habitat and conditions– Few measurements

– Large Savanna biomass burning region Northern Territory/North Western Australia

Existing atmospheric measurements

Cape Grim Baseline Air Pollution Station

– Continuous CO2, 13CO2

– CH4, CO, N2O Flux Towers

– Howard Springs– Cape Tribulation– Burdekin– Virginia Park– Janina– Tumbarumba– Maroondah

Solar FTIR remote sensing– Wollongong

In-situ FTIR– Aspendale– Field campaigns

Jenolan Caves Kyabram Tumbarumba

Cape Grim Baseline Air Pollution Station

– Continuous CO2, 13CO2

– CH4, CO, N2O

Forthcoming…

Global– OCO Satellite

Other more localised measurements– In situ FTIR

OCO Satellite Program Overview

– Orbiting Carbon Observatory– US-based (JPL-NASA)– Dedicated global CO2 mapping

– 3 parts1. Satellite measurements

2. Ground-based validation measurements

3. Inverse modelling

OCO – Validation Measurements (1)

Network of ground-based sites– Arrival Heights, Antarctica 78° S upgrade– Lauder, New Zealand 45° S upgrade– Wollongong, Australia 34° S new– Darwin, Australia 12° S new– Mauna Loa 20° N upgrade– Southern Great Plains, OK 36° N upgrade– Harvard Forest 42° N new– Park Falls 46° N new– Bremen 53° N existing– Poker Flat 65° N upgrade– Ny Alesund 79° N existing

Continuous in situ CO2 measurements by instrument traceable to CMDL standard (e.g. Li-Cor infrared analyzer)

Ancillary measurements of cloud, aerosol, radiation, and standard meteorological variables

OCO – Validation Measurements (2)

Major validation – ground-based solar FTS– Bruker 125HR (or equivalent)– Hi-resolution (0.02cm-1) FTNIR spectra (3500-15798cm-1)

More localised measurements

In-situ FTIR (OOOFTI) Continuous data

– Including night time Multi-species - CO2, CH4, CO,

N2O, 13CO2

~0.1% (0.3ppmv) precision CO2

Co-located with OCO ground validation

– Darwin– Lauder (trial currently underway)

Ghan railway (Adelaide to Darwin) An OOOFTI in Kyabram

My PhD Plan of action

1. Inverse modelling (1)• Planned measurements to determine their value

2. FTS Measurements

3. Inverse modelling (2)• Incorporate real measurements to determine source

estimates

Modelling (1) – Test phase

– Forward atmospheric transport model (CCAM) Generate synthetic data representative of the planned measurement

strategy

– Time Dependent Inverse (TDI) model Test value of additional measurements in determining sources and

uncertainties when added to a standard existing network

– CO2 only (currently)

– Background site network CMDL/NOAA flask sites – monthly averaged Continuous Cape Grim synthetic data

– Additional sites (separately, combined) Darwin Alice Springs Ghan Railway

Modelling Results

Uncertainty improvement - Darwin + basic network

Uncertainty improvement - Ghan railway + basic network

Ghan Railway

Ghan railway Darwin

Darwin & Ghan

Uncertainty improvement - Darwin AND Ghan Railway + basic network

Where to now?

Further investigate measurement strategies– Frequency of Ghan measurements– Combinations of sites– Indian-Pacific railway

Multi-species inversions– Use CH4, CO data as well as CO2

Using column measurements Measurements

– Lauder– Darwin– Ghan railway

Model the measurements– Australian carbon cycle information