Influence of Nonlinear Processes on the Time Lag between Changes in the Global Temperature and the Carbon Dioxide Content in the Atmosphere.

A nonlinear mechanism for the formation of a time lag between changes in the global surface temperature T and the carbon dioxide content in the atmosphere q is described. It is shown that the changes in T can either lag behind the changes in q or lead them, depending on the type of external forcing, its time scale, the amplitude, and the direction of the change in the state of the system. In particular, when the amplitudes of T and q are sufficiently large, the response of one variable to changes in the other is markedly different from the linear one: the dependence of T on changes in q is logarithmic, and the dependence of q on changes in T is close to exponential. In the case of variations on a time scale of several centuries, this results in T being ahead of q at the growth stage, and q ahead of T at the decreasing stage, regardless of the type of external forcing. [ABSTRACT FROM AUTHOR]