edu.ucar.opensky::articles:22087 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-25T15:47:30.519490 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d72f7rcx Peroxy acetyl nitrate (PAN) measurements at northern midlatitude mountain sites in April: a constraint on continental source–receptor relationships 2018-10-25T00:00:00Z publication https://n2t.org/ark:/85065/d72f7rcx https://doi.org/10.5194/acp-18-15345-2018 Fiore, Arlene author Fischer, E. V. author Milly, G. P. author Pandey Deolal, S. author Wild, O. author Jaffe, D. A. author Staehelin, J. author Clifton, Olivia E. author Bergmann, D. author Collins, W. author Dentener, F. author Doherty, R. M. author Duncan, B. N. author Fischer, B. author Gilge, S. author Hess, P. G. author Horowitz, L. W. author Lupu, A. author MacKenzie, I. A. author Park, R. author Ries, L. author Sanderson, M. G. author Schultz, M. G. author Shindell, D. T. author Steinbacher, M. author Stevenson, D. S. author Szopa, S. author Zellweger, C. author Zeng, G. author UCAR/NCAR - Library publisher Abundance-based model evaluations with observations provide critical tests for the simulated mean state in models of intercontinental pollution transport, and under certain conditions may also offer constraints on model responses to emission changes. We compile multiyear measurements of peroxy acetyl nitrate (PAN) available from five mountaintop sites and apply them in a proof-of-concept approach that exploits an ensemble of global chemical transport models (HTAP1) to identify an observational "emergent constraint". In April, when the signal from anthropogenic emissions on PAN is strongest, simulated PAN at northern midlatitude mountaintops correlates strongly with PAN source-receptor relationships (the response to 20 % reductions in precursor emissions within northern midlatitude continents; hereafter, SRRs). This finding implies that PAN measurements can provide constraints on PAN SRRs by limiting the SRR range to that spanned by the subset of models simulating PAN within the observed range. In some cases, regional anthropogenic volatile organic compound (AVOC) emissions, tracers of transport from different source regions, and SRRs for ozone also correlate with PAN SRRs. Given the large observed interannual variability in the limited available datasets, establishing strong constraints will require matching meteorology in the models to the PAN measurements. Application of this evaluation approach to the chemistry-climate models used to project changes in atmospheric composition will require routine, long-term mountaintop PAN measurements to discern both the climatological SRR signal and its interannual variability. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright 2018 Author(s). This work is licensed under a Creative Commons Attribution 4.0 International license. None eng geoscientificInformation