Routine application of novel stable isotope spectroscopy instruments
December 12, 2010
University of California, Berkeley
- Continuous field observations of stable isotope abundance ("Getting the data") - Knohl, Sturm, Siegwolf, Zeeman ►pdf
- Measuring δ13C and δ18O of CO2 at Harvard Forest using a Quantum Cascade Laser Spectrometer - Wehr, Munger, Nelson, McManus, Zahniser, Saleska ►pdf
- Daily work with stable isotope spectroscopy instruments (and the things that DO not end up in papers) - Wingate, Ogée, Burlett, Bosc ►pdf
- Daily work with stable isotope spectroscopy instruments in Hesse forest - Plain, Parent, Longdoz, Marron, Epron ►pdf
- Experience with isotope-specific laser instrument - Brüggemann ►pdf
- Calibration for DXS: Measurements from Mauna Loa 2008 - Noone ►pdf
- Vertical profiles of water vapor isotopic composition from in-situ measurements - Noone, Risi, Bailey, Brown, Buenning, Nusbaumer, Sykes, Schneider, Vanderwende, Wong, Meillier, Wolf ►pdf
- Meeting Notes ►pdf
(...and the things that do not end up in papers)
2010-12-12, 13:00 - 17:00 hrs, UC Berkeley, Berkeley, USA
-- Valley Life Science Building (VLSB) / Room 2063 --
We think it would be of importance to have our stable isotope community come up with solutions
to better utilize the new spectroscopy technologies in continuous operation at field sites and
prepare for future collaborative opportunities, e.g. within new observational networks.
Discuss what works best and what did not work well, document these outcomes and report to
Introduction presentations, by the speakers listed below:
1. Matthias J. Zeeman, Oregon State University, Corvallis (OR), USA.
2. Rick Wehr, University of Arizona, Tucson (AZ), USA.
3. Lisa Wingate, University of Cambridge, Cambridge, UK / University of Edinburgh,
4. Daniel Epron, University of Nancy / Université Henri Poincaré, Nancy, France.
5. Nicolas Brueggemann, Forschungszentrum Jülich, Jülich, Germany.
6. David Noone, University of Colorado, Boulder (CO), USA.
7. Camille Risi, University of Colorado, Boulder (CO), USA.
The following topics were discussed:
At lab level
● Instrument characterization (lab, field) and calibration (field) are strongly application
● Instrument characterization and calibration information should be added to papers (as
● Instrument characterization
○ Instrument drift & precision (single gas, Allan variance statistics)
○ Response time & memory effects (step change, Allan variance statistics, (co)
spectra. turbulence measures)
○ Cross sensitivity & interference (remove substance or correct, e.g. purging of the
optical path, permeation drying of inlet gas)
○ Temperature sensitivity (analyze, stabilized ambient conditions, e.g. micro-dosing
LN for detectors, water cooling for lasers, air conditioning)
○ Effect of your sampling system (tube heating, below ambient pressure, effect of
different tubing materials)
○ Check if the calibration response is linear.
○ Generally, a 2-3 points calibration based on individual isotopologues. Delta
values derived from isotopologue mixing ratios only in a final step.
○ Make sure that you bracket calibration well for the expected mixing and delta
ratio range, as there are non-linear effects. Particularly important for labeling
○ Tie calibrations to mass spectrometer measurements.
● Keep spectra for long-term QC. Open questions: Data space considerations, info on how
to calibrate or use the spectra needs to be made available from manufacturers.
At community level
What could be helpful to share/compare/standardize within the community and how:
● Standardization and comparison of H2O isotope measurement setups:
○ SMOW and Vostok standards do not cover the range found in the field; we need
○ A performance test of currently used vaporizer systems and methods: through
a ring exchange of liquid standards among labs, or the use of bottled Evian or
Deep Blue as used at SIRFER (http://sirfer.utah.edu).
● Standardization of CO2 isotope measurement setups
○ Tanks or flasks sources: IMECC, ICOS/NEON?
○ Or produce your own flasks/tanks and sent it to mass spectrometer labs.
● Comparison of data processing:
○ use of Golden files, similar to Ameriflux/CarboEuroflux, only for EC or just use
existing CO2 golden files
● Reporting and communicating progress and issues:
○ Need for a new journal. For example, RCM is no longer accepting spectroscopy
work (without IRMS).
○ Exchange of information through BASIN (end of funding), NEON or SIBAE
○ Peer-reviewed Wikis. For example, Prometheus (http://
prometheuswiki.publish.csiro.au); A CSIRO managed, peer-reviewed wiki
for ‘Protocols in ecological & environmental plant physiology’
○ Manufacturer websites, e.g. Picarro forum.
Reporting of this meeting
● Online publication of the presentations and meeting notes.
○ BASIN: http://basin.yolasite.com/
○ SIBAE: http://www.sibae.ethz.ch/cost-sibae/
● Submit a meeting report to inform the broader community of our activities, e.g. to AGU’s EOS.
● An international, collaborative effort for “best practice” guidelines (or tech note
publication) is not considered at this time.
LIST OF ATTENDEES
The following (37) persons were present:
Mark Blonquist David Nelson (Aerodyne)
Dave Bowling David Noone
Nicolas Brueggemann Heath Powers
Matthias Cuntz Thom Rahn
Claudia Czimczik Camille Risi
Masako Dannoura Adam Roddy
Todd Dawson Scott Saleska
Daniel Epron Greg Santoni
Jim Ehleringer Ulli Seibt
Iain Green (Picarro) Rolf Siegwolf
John Hunt Kevin Simonin
Ali Ismail Kevin Tu
Larry Jacobsen (Campbell Sci) Aaron Van Pelt (Picarro)
Hans-Joerg Jost (Thermo-Fisher/ Novawave) Bruce Vaughn
Alexander Knohl Eric Wapelhorst (Thermo-Fisher/ Novawave)
Xuhui Lee Rick Wehr
Hank Loescher Lisa Wingate
Hongyan Luo Matthias Zeeman
Dayle McDermitt (LI-COR)
Matthias Zeeman (Oregon State University)
Alexander Knohl (ETH Zurich/U Goettingen)
Kevin Tu (UC Berkeley)
This meeting was supported by BASIN. Many thanks to the speakers for presenting their work and making their presentations available.