Structural Cointegration of the Climate--Carbon Feedback: Evidence from the Last 130,000 Years
Abstract
Using a gap-free, millennial-resolution ice-core record spanning the last 130,000 years, we identify the feedback architecture between Antarctic temperature and atmospheric CO. The series are found to be cointegrated, justifying estimation with a Vector Error Correction Model (VECM). The estimated long-run relationship yields a temperature change of 13.0 K per CO doubling. Structural identification combining Milankovitch-cycle instrumental variables with the VECM residuals yields a contemporaneous carbon response (CCR) of 5.77 ppm/K, whereas the contemporaneous temperature response (CTR) is statistically indistinguishable from zero. Accounting for lagged feedbacks, the cumulative temperature response within one millennium of CO doubling reaches 11.8 K.
Keywords
Cite
@article{arxiv.2601.06986,
title = {Structural Cointegration of the Climate--Carbon Feedback: Evidence from the Last 130,000 Years},
author = {Satoshi Nakano and Kazuhiko Nishimura},
journal= {arXiv preprint arXiv:2601.06986},
year = {2026}
}