A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback - Koven, C.D.; Schuur, E.A.G.; Schädel, C.; Bohn, T.; Burke, E.; Chen, G.; Chen, X.; Ciais, P.; Grosse, G.; Harden, J.W.; Hayes, D.J.; Hugelius, G.; et al. (Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2015)