Uncertainty in temperature response of current consumption-based emissions estimates

J Karstensen,G P Peters,R M Andrew

doi:10.5194/esd-6-287-2015

J Karstensen, G P Peters + Show 1 more

Open Access

https://doi.org/10.5194/esd-6-287-2015

Copy DOI

Abstract

Abstract. Several studies have connected emissions of greenhouse gases to economic and trade data to quantify the causal chain from consumption to emissions and climate change. These studies usually combine data and models originating from different sources, making it difficult to estimate uncertainties along the entire causal chain. We estimate uncertainties in economic data, multi-pollutant emission statistics, and metric parameters, and use Monte Carlo analysis to quantify contributions to uncertainty and to determine how uncertainty propagates to estimates of global temperature change from regional and sectoral territorial- and consumption-based emissions for the year 2007. We find that the uncertainties are sensitive to the emission allocations, mix of pollutants included, the metric and its time horizon, and the level of aggregation of the results. Uncertainties in the final results are largely dominated by the climate sensitivity and the parameters associated with the warming effects of CO2. Based on our assumptions, which exclude correlations in the economic data, the uncertainty in the economic data appears to have a relatively small impact on uncertainty at the national level in comparison to emissions and metric uncertainty. Much higher uncertainties are found at the sectoral level. Our results suggest that consumption-based national emissions are not significantly more uncertain than the corresponding production-based emissions since the largest uncertainties are due to metric and emissions which affect both perspectives equally. The two perspectives exhibit different sectoral uncertainties, due to changes of pollutant compositions. We find global sectoral consumption uncertainties in the range of ±10 to ±27 % using the Global Temperature Potential with a 50-year time horizon, with metric uncertainties dominating. National-level uncertainties are similar in both perspectives due to the dominance of CO2 over other pollutants. The consumption emissions of the top 10 emitting regions have a broad uncertainty range of ±9 to ±25 %, with metric and emission uncertainties contributing similarly. The absolute global temperature potential (AGTP) with a 50-year time horizon has much higher uncertainties, with considerable uncertainty overlap for regions and sectors, indicating that the ranking of countries is uncertain.

Highlights

Many studies have shown that national greenhouse gas (GHG) emission accounts can be viewed from either a production or consumption perspective (Davis and Caldeira, 2010; Hertwich and Peters, 2009; Wiedmann, 2009; Peters and Hertwich, 2008)
We extend the uncertainty analyses done by Prather et al (2009), Höhne et al (2010), and den Elzen et al (2005) by including consumption-based emissions for a single year and using a temperature-based emission metric, which is arguably a more policy-relevant method of weighting emissions
We consider the propagation of uncertainty from the point of consumption of goods and services, to the production of products where emissions occur, to the climate impacts caused by those emissions (Fig. 1). This can be thought of as a causal chain where consumption is assumed to be the primary driver, in turn driving production, which in turn leads to emissions, which lead to temperature change. These components of the cause–effect chain are linked by calculation methodologies, each requiring parameterization, and we break the analysis into those three components: economic data, emission statistics, and emission metrics

Summary

Introduction

Many studies have shown that national greenhouse gas (GHG) emission accounts can be viewed from either a production (territorial) or consumption perspective (Davis and Caldeira, 2010; Hertwich and Peters, 2009; Wiedmann, 2009; Peters and Hertwich, 2008). It has been shown that territorial emissions have decreased in most developed countries since 1990, but consumption-based emissions have increased (Peters et al, 2011c). This indicates that growth in consumption and international trade may undermine the effectiveness of climate policies that only limit emissions in a subset of countries, such as in the Kyoto Protocol (Wiebe et al, 2012; Kanemoto et al, 2013).

Methods

Results

Discussion

Conclusion