%0 Journal Article
%K Inverse modeling
%K Atmospheric transport
%K Nitrous oxide
%A Seongeun Jeong
%A Chuanfeng Zhao
%A Arlyn E Andrews
%A Edward J Dlugokencky
%A Colm Sweeney
%A Laura Bianco
%A James M Wilczak
%A Marc L Fischer
%B Geophysical Research Letters
%D 2012
%N 16
%R 10.1029/2012GL052307
%T Seasonal variations in N<sub>2</sub>O emissions from central California
%V 39
%X <p>We estimate nitrous oxide (N<sub>2</sub>O) emissions from Central California for the period of December 2007 through November 2009 by comparing N<sub>2</sub>O mixing ratios measured at a tall tower (Walnut Grove, WGC) with transport model predictions based on two global <em>a priori</em> N<sub>2</sub>O emission models (EDGAR32 and EDGAR42). Atmospheric particle trajectories and surface footprints are computed using the Weather Research and Forecasting (WRF) and Stochastic Time-Inverted Lagrangian Transport (STILT) models. Regression analyses show that the slopes of predicted on measured N<sub>2</sub>O from both emission models are low, suggesting that actual N<sub>2</sub>O emissions are significantly higher than the EDGAR inventories for all seasons. Bayesian inverse analyses of regional N<sub>2</sub>O emissions show that posterior annual N<sub>2</sub>O emissions are larger than both EDGAR inventories by factors of 2.0 ± 0.4 (EDGAR32) and 2.1 ± 0.4 (EDGAR42) with seasonal variation ranging from 1.6 ± 0.3 to 2.5 ± 0.4 for an influence region of Central California within approximately 150 km of the tower. These results suggest that if the spatial distribution of N<sub>2</sub>O emissions in California follows the EDGAR emission models, then actual emissions are 2.7 ± 0.5 times greater than the current California emission inventory, and total N<sub>2</sub>O emissions account for 8.1 ± 1.4% of total greenhouse gas emissions from California.</p>