metnh3 june 2014 - may 2017 3,no 5 christine braban 6 ...€¦ · n fluxes in tgn/yr export by...
TRANSCRIPT
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
AC4 AC4 SS SS SS+ SS+ otherotherNo
rma
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ed
Re
sp
on
se
Fa
cto
r / a
rbit
rary
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its
Cylinder Treatment
NPL
VSL
• Development of two facilities has been started in order to characterise different ammonia analysers as well as passive samplers and denuders.
• The NPL Controlled Atmosphere Test Facility (CATFAC) is being tested for generating stable NH3 concentration, under controlled T, RH and wind speed.
• the first ammonia test measurements and testing of a CRDS to minimise cross interference effects by water vapour.
• Testing of different designs of passive samplers and denuders is underway
• UBA has started the characterization of a Proficiency Test Facility for ammonia measurements.
• The proficiency test facility will be capable of providing 12 individual working places with well characterized test gas mixtures containing ammonia and common atmospheric trace gases with intercomparison planned for 2016
• NERC CEH is researching inlets for NH3 and designing a mobile instrument-response testing system.
• Field intercomparison planned for Scotland in summer/autumn 2016. • Contact [email protected] or [email protected] if interested in participating
MetNH3: Metrology for ammonia in ambient air June 2014 - May 2017
Collaborating
organisations
This work is
funded by:
1. Gas calibration standards
What are ambient ammonia concentrations?
2. Optical spectrometric standards.
Why is now the time to improve ammonia metrology?
How can the research community get involved?Become a Stakeholder/Collaborator
…
MetNH3 Project objectives
• Ambient ammonia concentrations are highly variable, e.g.:
remote or background <1.5 ppb
agricultural and urban background 1.5-20 ppb
source impacted >20 ppb
• Climate conditions: Temperature (T) and relative humidity
(RH) affect both ambient concentrations &
instrument/sampler performance
• Highly dependent on PM e.g. ammonium-nitrate-sulphate
with re-partitioning of ammonia to gas phase possible
• Development and characterisation of extractive optical transfer standards beyond the state-of-the-art
• Characterisation and application of sampling-free open path laser spectrometers
3. Validation/Dissemination to field measurement techniques
• Ammonia is a major pollutant, key to understanding ambient air quality including PM & atmospheric impacts on ecosystems
• The Executive Body to the UN Convention on Long-range Transboundary Air Pollution is due to adopt a guidance document on preventing and abating ammonia emissions from agricultural sources*
• Recent developments have occurred in the range and capability of spectroscopic instruments available for measurements
• Integration and intercomparability of low-cost low-temporal resolution ammonia measurements with high-cost high-temporal resolution
• There is a need to improve the metrology from standards at the ppm mixing ratios to concentrations more relevant to ambient atmospheric concentrations
6548.5 6548.6 6548.7 6548.8 6548.9 6549.0 6549.1 6549.2 6549.3
7.6x10-7
7.7x10-7
7.8x10-7
7.9x10-7
8.0x10-7
8.1x10-7
8.2x10-7
8.3x10-7
8.4x10-7
8.5x10-7
8.6x10-7
8.7x10-7
measured data
fitted spectrum
NH3
H2O
baseline
6548.6 6548.7 6548.8 6548.9 6549.07.58x10
-7
7.60x10-7
7.62x10-7
7.64x10-7
7.66x10-7
7.68x10-7
Wavenumber / cm-1
Ab
so
rptio
n c
oe
ffic
ien
t /
cm
-1
Measured and fitted spectrum and residuals in 100 nmol/mol NH3 and 2% H2O in synthetic air.
Measured with a Picarro G2103 CRDS spectrometer.
Humannutrit.
agricult
soils
Livestock
farming
Atmospheric N2 pool
Crop
production
Atm
depos
17.6
7.1
11.8
1.5
2.14.5
2.3
1.0
3.1
Net import of
food & feed
2Crop
N2fix
Fertilizers
11.23.8
NH3,NOx
& N2O
emission
Denitrifi-
cation
N2 fixindust
& traffic3.4
Europe (EU27), around 2000. N fluxes in TgN/yr
Export by
rivers to
the sea
Net atmosph. export
9.3
2.4
3.5
6.84
6
13.8
0.4
4.75.8
3.7
0.8
3.2
0.1
Semi-nat.
soils
Nat N2fix
Wood exp.
Atmospheric NH3, NOx, N2O
wwt
Leaching
& runoff
0.3
2.41.4
0.2
3.8
0.2
0.2
4.7
6
4
3
2
1
5
7
N flows in Europe (numbers: TgN/yr), ENA 2011
• Instrument technologies available include cavity ring-down, MIR quantum cascade laser, photoacoustic spectrometers
• Extractive cavity ring-down spectrometers (CRDS) from PicarroInc. are being evaluated
• PTB and DFM began to evaluate the possibility of absolute operation of the spectrometers.
Christine Braban, Marsailidh Twigg, Sim Tang, John Kentisbeer, Daiana Leuenberger, Valerio Ferracci, Nathan Cassidy, Nick Martin, Celine Pascale, Tuomas Hieta, Andrea Pogany, Volker Ebert, Stefan Persijn, Janneke van Wijk, Holger Gerwig, Klaus Wirtz, Carlo
Tiebe, David Balslev-Harder, and Bernhard Niederhauser
http://www.metnh3.eu
Get the project newsletter!Contact Project coordinator:
Bernhard Niederhauser [email protected]
Pre-announcements:
Stakeholder/Project Workshop May 2016 Ammonia field intercomparison in summer/autumn 2016
• The partners from NPL and VSL have produced reference gas mixtures prepared by gravimetry at
• 10 ppm• 100 ppm
• These mixtures are stored in different commercially available cylinders in order to test their long-term stability over the course of the project.
• Comparison is of individual cylinders at 10ppm ammonia in nitrogen to determine the best surface treatment for ammonia mixtures and to quantify absorption of ammonia on cylinder walls
H2O, CO2 and O3 are potential spectrally interfering components the optimal wavelength range selected based on HITRAN2012 & the literature Testing of CRD instruments has started. Initial results show that water correction
is challenging• Partners BAM and METAS have started working on two
mobile generators for the dynamic generation of reference gas mixtures. These devices will generate & dilute NH3 0.5-500 ppb.
• Research on the adsorption of NH3 on various material surfaces will commence involving the partners VSL and METAS together with CEH and UH
• Design and assembly of a sampling-free spectrometer based on an open multiple-pass cell and a QCL has been started at MIKES.
• New static reference gas mixtures in pressurised cylinders • Development of devices for dynamic generation of traceable reference gas
mixtures by permeation and dilution with portability
• Validation and comparison of field applicable (wet) methods with optical transfer standards • Evaluate field applicable methods for monitoring of reduction measures
1. Gas calibration standards
3. Validation/Dissemination
2. Optical spectrometric standards
http://www.unece.org/fileadmin/DAM/env/documents/2014/AIR/EB/ECE_EB_AIR_2014_8_E.pdf*
Project Partners