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Aggregation of carbon dioxide sequestration storage assessment units

Stochastic Environmental Research and Risk Assessment

By:
, , , and
DOI: 10.1007/s00477-013-0718-x

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Abstract

The U.S. Geological Survey is currently conducting a national assessment of carbon dioxide (CO2) storage resources, mandated by the Energy Independence and Security Act of 2007. Pre-emission capture and storage of CO2 in subsurface saline formations is one potential method to reduce greenhouse gas emissions and the negative impact of global climate change. Like many large-scale resource assessments, the area under investigation is split into smaller, more manageable storage assessment units (SAUs), which must be aggregated with correctly propagated uncertainty to the basin, regional, and national scales. The aggregation methodology requires two types of data: marginal probability distributions of storage resource for each SAU, and a correlation matrix obtained by expert elicitation describing interdependencies between pairs of SAUs. Dependencies arise because geologic analogs, assessment methods, and assessors often overlap. The correlation matrix is used to induce rank correlation, using a Cholesky decomposition, among the empirical marginal distributions representing individually assessed SAUs. This manuscript presents a probabilistic aggregation method tailored to the correlations and dependencies inherent to a CO2 storage assessment. Aggregation results must be presented at the basin, regional, and national scales. A single stage approach, in which one large correlation matrix is defined and subsets are used for different scales, is compared to a multiple stage approach, in which new correlation matrices are created to aggregate intermediate results. Although the single-stage approach requires determination of significantly more correlation coefficients, it captures geologic dependencies among similar units in different basins and it is less sensitive to fluctuations in low correlation coefficients than the multiple stage approach. Thus, subsets of one single-stage correlation matrix are used to aggregate to basin, regional, and national scales.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Aggregation of carbon dioxide sequestration storage assessment units
Series title:
Stochastic Environmental Research and Risk Assessment
DOI:
10.1007/s00477-013-0718-x
Volume
27
Issue:
8
Year Published:
2013
Language:
English
Publisher:
Springer
Contributing office(s):
Eastern Energy Resources Science Center
Description:
21 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Stochastic Environmental Research and Risk Assessment
First page:
1839
Last page:
1859