Published November 1980. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Firn air transport models are used to interpret measurements of the composition of air in firn and bubbles trapped in ice in order to reconstruct past atmospheric composition. The diffusivity profile in the firn is usually calibrated by comparing modelled and measured concentrations for tracers with known atmospheric history. However,...
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diffusivity profile?
C. M. Trudinger1, I. G. Enting2, P. J. Rayner3, D. M. Etheridge1, C. Buizert4,5, M
Firn air transport models are used to interpret measurements of the composition of air in firn and bubbles trapped in ice in order to reconstruct past atmospheric composition. The diffusivity profile in the firn is usually calibrated by comparing modelled and measured concentrations for tracers with known atmospheric history. However,...
Full Text:
the firn diffusivity profile?
Supplementary material
C. M. Trudinger1, I. G. Enting2, P. J. Rayner3, D
Inorganic nitrate (NO₃⁻) and ammonium (NH₄⁺) are the two major components in nitrogen (N) nutrition of typical tissue culture growth media, and the total amounts and ratios influence both shoot induction and differentiation. This study was designed to determine the optimal N requirements and interactions of NH₄⁺×NO₃⁻ to complete the...
New ice core analyses show that the prominent rise in atmospheric methane concentration at Dansgaard-Oeschger event 21 was interrupted by a century-long 20% decline, which was previously unrecognized. The reversal was found in a new ∼100-year resolution study of methane in the GISP2 ice core, encompassing the beginning of D-O...
Air was sampled from the porous firn layer at the NEEM site in Northern Greenland. We use an ensemble of ten reference tracers of known atmospheric history to characterise the transport properties of the site. By analysing uncertainties in both data and the reference gas atmospheric histories, we can objectively...
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. M. Trudinger5, E. Witrant6, J. L. Rosen7,
A. J. Orsi4, M. Rubino1,5, D. M. Etheridge1,5, L. P
Understanding the processes that control the terrestrial exchange of carbon is critical for
assessing atmospheric CO₂ budgets. Carbonyl sulfide (COS) is taken up by vegetation during
photosynthesis following a pathway that mirrors CO₂ but has a small or nonexistent emission component,
providing a possible tracer for gross primary production. Field...
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measurements of
carbonyl sulfide and carbon dioxide
Berkelhammer, M., D. Asaf, C. Still, S. Montzka, D. Noone
The global biogeochemical cycle of methane has received wide attention because of methane's role as a greenhouse gas. Measurements of methane in air trapped in Greenland ice cores provide a high-resolution record of methane levels in the atmosphere over the past ~100 ka, providing clues about what controls the methane...