Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatio-Temporal Reconstructions of Global CO2-Fluxes using Gaussian
  Markov Random Fields   Atmospheric inverse modelling is a method for reconstructing historical
fluxes of green-house gas between land and atmosphere, using observed
atmospheric concentrations and an atmospheric tracer transport model. The small
number of observed atmospheric concentrations in relation to the number of
unknown flux components makes the inverse problem ill-conditioned, and
assumptions on the fluxes are needed to constrain the solution. A common
practise is to model the fluxes using latent Gaussian fields with a mean
structure based on estimated fluxes from combinations of process modelling
(natural fluxes) and statistical bookkeeping (anthropogenic emissions). Here,
we reconstruct global \CO flux fields by modelling fluxes using Gaussian Markov
Random Fields (GMRF), resulting in a flexible and computational beneficial
model with a Mat\'ern-like spatial covariance, and a temporal covariance
defined through an auto-regressive model with seasonal dependence.
  In contrast to previous inversions, the flux is defined on a spatially
continuous domain, and the traditionally discrete flux representation is
replaced by integrated fluxes at the resolution specified by the transport
model. This formulation removes aggregation errors in the flux covariance, due
to the traditional representation of area integrals by fluxes at discrete
points, and provides a model closer resembling real-life space-time continuous
fluxes.

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The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
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The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
3
The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: cmp-lg
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The categories of this paper are: bayes-an