Non-Gaussian bivariate modelling with application to atmospheric trace-gas inversion

Andrew Zammit Mangion, Noel Cressie, Anita Ganesan

Research output: Contribution to journalArticle (Academic Journal)peer-review

5 Citations (Scopus)
266 Downloads (Pure)

Abstract

Atmospheric trace-gas inversion is the procedure by which the sources and sinks of a trace gas are identified from observations of its mole fraction at isolated locations in space and time. This is inherently a spatio-temporal bivariate inversion problem, since the mole-fraction field evolves in space and time and the flux is also spatio-temporally distributed. Further, the bivariate model is likely to be non-Gaussian since the flux field is rarely Gaussian. Here, we use conditioning to construct a non-Gaussian bivariate model, and we describe some of its properties through autov and cross-cumulant functions. A bivariate non-Gaussian, specifically trans-Gaussian, model is then achieved through the use of Box–Cox transformations, and we facilitate Bayesian inference by approximating the likelihood in a hierarchical framework. Trace-gas inversion, especially at high spatial resolution, is frequently highly sensitive to prior specification. Therefore, unlike conventional approaches, we assimilate trace-gas inventory information with the observational data at the parameter layer, thus shifting prior sensitivity from the inventory itself to its spatial characteristics (e.g., its spatial length scale). We demonstrate the approach in controlled experiment studies of methane inversion, using fluxes extracted from inventories of the UK and Ireland and of Northern Australia.
Original languageEnglish
Pages (from-to)194-220
Number of pages27
JournalSpatial Statistics
Volume18 Part A
Early online date23 Jun 2016
DOIs
Publication statusPublished - Nov 2016

Keywords

  • Bivariate spatial model
  • Conditional multivariate model
  • Methane emissions
  • Multivariate geostatistics
  • Trans-Gaussian model
  • Box–Cox transformation

Fingerprint Dive into the research topics of 'Non-Gaussian bivariate modelling with application to atmospheric trace-gas inversion'. Together they form a unique fingerprint.

Cite this