Quality Management Framework in the WMO Global Atmosphere Watch

Programme

Oksana TarasovaWMO Research Department

The GAW Programme

End-to-end research programmerelated to atmospheric composition matters involving contribution from more than 100 countries

GAW groups of variables  • Stratospheric Ozone and vertical

ozone distribution

• Greenhouse Gases (CO2 and its isotopes , CH4 and its isotopes, N2/O2ratio, N2O, SF6, CFCs and substitutes)

• Reactive Gases (O3, CO, VOCs, NOx, SO2)

• Total Atmospheric Deposition

• Aerosols

• UV Radiation

In total about 60 variables are included

GAW Implementation Plan (2016‐2023): “science for services”

IP builds upon the premise that atmospheric composition matters to:• climate, • weather

forecasting,• human health,• terrestrial and

aquatic ecosystems,

• agricultural productivity,

• aeronautical operations, etc

Paris Agreement – limit the temperature increase by 2C by limiting emissions

Calculations are for year in 2011

Fundamental problem – it is what you HAVE in the atmosphere, not what you PUT in the atmosphere, that controls the temperature

Human (9GtC in) – ocean (2.3GtC out) –biosphere(2.6GtC out)

How to get emissions?• “Bottom‐up” measurements 

(SELF REPORTING)– Emissions reporting– Reported and “verified” offsets– Site‐specific measurements

• “Top‐down” measurements  – Comprehensive atmospheric 

observation system– Ecosystem and ocean 

observations– Inverse modelling

• Combination of above

NDCsNDCs

Assuming that we know ocean and biosphericuptake

NDC are evaluated every 5 years -> are we on the right track?Where can we cut more?Are oceans and biosphere are working as expected?

The Integrated Global Greenhouse Gas Information System (IG3IS)

Goal: Support the success of post‐COP21 actions of nations, sub‐national governments, and the private sector to reduce climate‐disrupting GHG emissions through a sound‐scientific, measurement‐based approach that:

– reduces uncertainty of national emission inventory reporting, – identifies large and additional emission reduction opportunities, and

– provides nations with timely and quantified guidance on progress towards their emission reduction strategies and pledges (e.g., NDCs)

EC-68 endorsed the IG3IS concept paper

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1,000

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Mace Head - error barsrepresent the 5th and 95thpercentiles

DECC - error bars representthe 2.5th and 97.5thpercentiles

UK GHGI - error barsrepresent the 2.5th and97.5th percentiles

• Early (1990s) mismatch with the inventory.

• Difficult to understand, most likely cause is landfill emissions but retrospectively challenging to investigate.

• Inspired DECC to expand the network from 1 to 4 stations.

Example from UK report to UNFCCC: Methane

Page 9

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Develop IG3IS System

Establish Baselines

Critical Period for detection of progress toward global emission reductions

Higher fidelity info to track and fine-tune progress

Enhance IG3IS System Maintain IG3IS System

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How will UNFCCC “Global Stocktake” evaluate greenhouse gas emissions reductions?

2020 2030 2050 2100

Tier2 (Blue boxes):Aircraft spectrometers estimates local fluxes & attributes source sectors

Tier 3: Plume Imaging aircraft map point sources

50 km

500 m

Tier 1: Satelite detects hotspot region

500 km

Pixel size 1.5m

Example of additional emission reduction opportunitiesTu

rner

et a

l 201

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Taft dairies

Kern River oil field

Elk Hills oil field

Dairies

Oil fields

Tier 4 (not shown):Surface observations

EnhancedActivity Data

“Nesting” – from the planet to a building

• Global consistency• Consistency across scales• standardization

Motivation for the GAW Quality Assurance System

For GAW network compatibility is needed for:- Detection of small spatial gradients- Estimation of temporal trends/variability- Calculation of global averaged values- Use in inverse modelling and comparison with

model simulations - Comparison with satellite observations- Long-term stability of network reference

(possibility to joint programme at any time point without introducing the bias).

Adequate gathering of data related to state of the global atmosphere – and analysis of anthropogenic impact on a global scale – would require that all measurements be expressed in the same units and on the same scale, such that measurements performed by different countries are comparable.

Quality Management Framework  principles

Network-wide use of only one reference standard or scale (primary standard).In consequence, there is only one institution that is responsible for this standard. Full traceability to the primary standard of all measurements made byGlobal, Regional and Local stations and of the primary standard of thecontributing networks. The definition of data quality objectives (DQOs). Establishment of guidelines on how to meet these quality targets, i.e.,harmonized measurement techniques based on Measurement Guidelines (MGs)and Standard Operating Procedures (SOPs). Establishment of MGs or SOPs for these measurements. Use of detailed log books for each parameter containing comprehensive metainformation related to the measurements, maintenance, and 'internal'calibrations. Regular independent assessments (system and performance audits). Timely submission of data and associated metadata to the responsible WorldData Centre as a means of permitting independent review of data by a widercommunity.

There are two realizations of network references:- reference materials- reference instruments

The reference materials are realized in the form of gas standards for long-lived greenhouse gases, some Volatile Organic Compounds (VOCs), NO, CO or reference solutions for precipitation chemistry measurements.

Measurements traceability in GAW

For ozone and for some aerosol characteristics the network references are realized though reference instruments, as direct realization of the substance is impossible or not practical.

In the area of UV Radiation measurements direct traceability to SI units has been broadly adopted.

Complexity of GAW QA implementation

• GAW has six groups of variables with completely different properties (long-lived gases, short-lived gases, total column, physical properties of aerosols, chemical properties of aerosols, chemical composition of aerosols and rain water)

• Different variables allow for different traceability chain• Different groups express requirements in a different way

Within GAW Central Calibration Laboratories are responsible for support of the network reference (standard or scale)

Data Quality Objectives for GHG

Reviewed at GGMT-2015

Component Compatibility goal Extended compatibility

goal

Range in unpolluted

troposphere

Range covered by the WMO scale

CO2 ± 0.1 ppm (Northern hemisphere)± 0.05 ppm (South. hemisphere)

± 0.2 ppm 380 - 450 ppm 250 – 520 ppm

CH4 ± 2 ppb ± 5 ppb 1750 – 2100 ppb 300 – 5900 ppbCO ± 2 ppb ± 5 ppb 30 – 300 ppb 30 - 500 ppbN2O ± 0.1 ppb ± 0.3 ppb 325 – 335 ppb 260 – 370 ppbSF6 ± 0.02 ppt ± 0.05 ppt 8 – 10 ppt 2.0 – 20 pptH2 ± 2 ppb ± 5 ppb 400 – 600 ppb 140 −1200 ppbδ13C-CO2 ± 0.01‰ ± 0.1‰ -7.5 to -9.5‰ vs.

VPDB-CO2δ18O-CO2 ± 0.05‰ ± 0.1‰ -2 to +2‰ vs.

VPDB-CO2∆14C-CO2 ± 0.5‰ ± 3‰ -50 - 50‰∆14C-CH4 ± 0.5‰ 50 - 350‰∆14C-COδ13C-CH4

± 2 molecules cm-3

± 0.03‰ ± 0.2‰0-25 molecules cm-3

δD-CH4 ± 1‰ ± 5‰O2/N2 ± 2 per meg ± 10 per meg -400 to -900 per

meg (vs. SIO scale)

Data Quality Objectives for Nitrogen Oxides

Level 1 (basic) 2 (enhanced) 3 (high)

Site characteristics Continental basic Continental background

Pristine, marine 

background, free 

troposphere

Mean mole fraction 

NOx

> 1 nmol/mol 0.1 – 1 nmol/mol < 0.1 nmol/mol

Scope (corresponding 

time resolution)

long term monitoring, trends (1 hour),

source‐receptor‐relationship, transport processes (hour‐minute), 

photochemical process studies (minute)

Detection Limit

(1 hour, 3σ)

NO: 50 pmol/mol

NO2:100 pmol/mol

NO: 10 pmol/mol

NO2:20 pmol/mol

NO: 1 pmol/mol

NO2:5 pmol/mol

uncertainty

(1 hour, 2σ)2NO: 40 pmol/mol or 3%

NO2:80 pmol/mol or 5%

NO: 8 pmol/mol or 3%

NO2:15 pmol/mol or 5%

NO: 1 pmol/mol  or 3%

NO2:3 pmol/mol or 5%

uncertainty

(1 month, 2σ)3NO: 2.5%

NO2: 3%

NO: 2.5%

NO2: 3%

NO: 1 pmol/mol or 2.5%

NO2:3 pmol/mol or 3%

data coverage 66%

GAW Global Central Facilities

Five types of central facilities:• Central Calibration Laboratories (CCLs)• Quality Assurance/Science Activity Centres

(QA/SACs)• World Calibration Centres (WCCs)• Regional Calibration Centres (RCCs)• World Data Centres (WDCs)

Stability of WMO Mole Fraction Scale for CO2

Courtesy of B.Hall

Propagation of WMO Mole Fraction Scale for CO2

WMO CO2 scale - Reference scale for CO2 in dry air, maintained by NOAA/GMD - Defined by 15 primary standards (~ 250 – 520 ppm)

Primary Standards Secondary Standards

Scale Transfer (NDIR)

Scale Transfer (NDIR)

Tertiary Standards

Courtesy of B.Hall

Stability of the Dobson primary  instrument

Courtesy: J. Staehelin

“Health” of the observational network

GAW Station Information System (GAWSIS)

Procedures for stations and networks are in place

The observational network evolution follows the Rolling Review of Requirementprocess

GAW observational network comprises: • Global stations (31)• Regional stations• Local stations• Mobile platform• Contributing networks (10)

Implementation of the GAW QMF

Comparison campaigns• global Round Robin comparisons• regional reference gas comparisons• Laboratory Intercomparison Studies (LIS)

• regional intercomparison campaigns for Brewer and Dobson instruments

• international filter radiometer comparisons

• instrumental workshops (by World Calibration Centre for Aerosols).

• NOAA ESRL prepared 9 high pressure cylinders (3 sets) of clean dry air, collected at Niwot Ridge for the intercomparison.

• Labs were divided into 3 globally‐distributed groups.

WMO Round‐Robin comparisons

6th Round-robin (2014 -2015 ): 43 Labs registered

Comparison campaigns

Results of WMO Round‐Robin comparison

Laboratory IntercomparisonStudies (LIS) are taking place twice every year. 54 LISs have taken place74 laboratories reported measurements for the last study.

The results of each laboratory are presented in the form of a ring diagram http://www.qasac-americas.org/.

Precipitation chemistry measurementsThe Illinois State Water Survey that serves as the Quality Assurance/Science Activity Centre – Americas (QA/SAC-Americas), has been providing standards for precipitation chemistry samples for many years. This is done in the context of sending test solutions to National Atmospheric Deposition Program stations for use in the field, and for the interlaboratory QA samples sent by the QA/SAC.

Comparison of selected instruments: ambient air (World Calibration Centre for 

Aerosol Physics)

0.1 1 101E-5

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10000 TROPOS SM PS Ref 3 LACY TS I OPS CRET E TS I OPS IDAEA GRIMM Sky OPS ISAC GRIMM 108 O PS JRC TS I APS UHEL TS I APS NILU GRIMM 190

dN/d

logD

p (1

/cm

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Particle diameter ( m)

Lab 121: Overnight 01.10.2014

(Courtesy: Ali Wiedensohler)

Particle size distribution measurements

EUSAAR Audits 2008 (PFR vs. Aeronet)

Cabauw Ispra

(Courtesy: ChristophWehrli)

Difference depends on the wavelength

Annual Comparison  Aeronet ‐ GAWPFR

Differen

ce dep

ends on locatio

n

(Courtesy: Christoph Wehrli)

Stations audits by Empa(1996‐2016)

TCCON Validation –relation to WMO scales

eg TWP‐ICE Darwin 2006 CO2 analyser on board Integrate vertical profile

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386384382380378376CO2 vmr (µmol.mol-1)

Aircraft CO2 Profile CO2

(Courtesy: D. Griffith)

Outlook- a comprehensive Quality Management Framework has been

established in GW - It is extremely important that QA activities are properly funded,

that personnel are trained, that good practices are developed, and that recommendations of audits and comparison campaigns are followed.

- There are still gaps in the GAW Quality Assurance Framework (measurement guidelines and Central Facilities) to be filled

- There is a need for standardizations of DQOs and improved treatment of measurement uncertainties

Further improvement of the QA system in GAW requires improved collaboration with CIMO. In particular, the establishment of regional calibration centres and quality assurance centres utilizing CIMO regional facilities would be beneficial.

Thank youMerci