New study in the Journal of Econometrics analyses the attribution of climate change to anthropogenic activities

New tests for common breaks sheds light on the causes of observed warming in global and hemispheric temperatures and on the existence of a slowdown in the warming in the late 20th Century.

06/14/2019 | 11:17 AM

IVM researcher Francisco Estrada is a co-author of a new paper published in the prestigious Journal of Econometrics that deals with extending current econometric tests to analyse the attribution of climate change. The contribution is part of the special issue Econometrics of Climate Change and it is the product of a collaboration with established econometricians: Pierre Perron from Boston University, Dukpa Kim from Korea University and Tatsushi Oka from Monash University. 

For almost a decade, Estrada and Perron have been working on the attribution of climate change and proposing new ways for conducting observation-based econometric studies of the effects of human activities on the climate system (see Estrada and Perron, 2014 for a summary). The existence of a slowdown in the warming trend since the mid-1990s has been of particular interest since its existence can help evaluating the extent human activities and the climate system are linked and the benefits of mitigation actions in the short term (Estrada, Perron and Martínez, 2013). The new paper by Kim, Oka, Estrada and Perron addresses two important issues that had remained unresolved. The first is to provide formal tests to analyse whether the changes in the rate of growth in temperatures and radiative forcing are common, which would strongly suggest a causal effect from anthropogenic forcing to temperatures (Estrada and Perron, 2019). 

The second issue is to properly evaluate statistically if the slowdown in the warming of the last decades is genuine or due to natural variability, as is often argued. The application of these new tests shows that the breaks in temperatures and radiative forcing are common and that the hiatus is characterized by a significant decrease in the rate of growth of anthropogenic forcing. The econometric tests developed in the paper can be used for a wide range of applications. 

Kim D., Oka T., Estrada F. & Perron P. (2019). Inference related to common breaks in a multivariate system with joined segmented trends with applications to global and hemispheric temperatures. Journal of Econometrics. Available at: https://www.sciencedirect.com/science/article/pii/S0304407619301113?via%3Dihub