Correcting errors from spatial upscaling of nonlinear greenhouse gas flux models

Van Oijen, Marcel; Cameron, David; Levy, Peter E. ORCID: https://orcid.org/0000-0002-8505-1901; Preston, Rory. 2017 Correcting errors from spatial upscaling of nonlinear greenhouse gas flux models. Environmental Modelling & Software, 94. 157-165. 10.1016/j.envsoft.2017.03.023

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Official URL: http://doi.org/10.1016/j.envsoft.2017.03.023

Abstract/Summary

Ecological models are used to quantify processes over large regions. When the model is nonlinear and input variables are spatially averaged, the regional mean will be in error. A formula for estimating the upscaling error can be derived from Taylor expansion of the model (Bresler and Dagan 1988). We test this for simple models under three different input distributions (Gaussian, exponential, lognormal). In several cases the formula is exact, in others it provides a reasonable approximation. We then study models for emissions of methane, ammonia, and nitrous oxide across the UK. We scale from 1 × 1 km to 32 × 32 km. The UK-average upscaling errors are −12%, −48% and −3%, well estimated using the formula. The formula is a useful tool for modellers desiring to correct upscaling error for their application. Calculation of second-order partial derivatives of model output is required, for which we provide R-code.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.1016/j.envsoft.2017.03.023
UKCEH and CEH Sections/Science Areas:	Dise
ISSN:	1364-8152
Additional Keywords:	block support, ecosystem modelling, greenhouse gas emission, point support, spatial upscaling, Taylor expansion
NORA Subject Terms:	Earth Sciences Ecology and Environment Mathematics Atmospheric Sciences Data and Information
Date made live:	10 May 2017 11:00 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/516907

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.1016/j.envsoft.2017.03.023

UKCEH and CEH Sections/Science Areas:

Dise

ISSN:

1364-8152

Additional Keywords:

block support, ecosystem modelling, greenhouse gas emission, point support, spatial upscaling, Taylor expansion

NORA Subject Terms:

Earth Sciences
Ecology and Environment
Mathematics
Atmospheric Sciences
Data and Information