The Earth’s climate system recurrent & multi-scale lagged responses: empirical law, evidence, consequent solar explanation of recent CO₂ increases & preliminary analysis

Abstract. This paper analyzes the lagged responses of the Earth’s climate system, as part of cosmic-solar-terrestrial processes. Firstly, we analyze and model the lagged responses of the Earth’s climate system, previously detected for geological and orbital scale processes, with simple non-linear functions, and we estimate a correspondent lag of ~1600-yr for the recently detected ~9500-yr scale solar recurrent patterns. Secondly, a recurrent and lagged linear influence of solar variation on volcanic activity and carbon dioxide (CO₂) has been assessed for the last millennia, and extrapolated for future centuries and millennia. As a consequence we found that, on one side, the recent CO₂ increase can be considered as a lagged response to solar activity, and, on the other side, the continental tropical climate signal during late Holocene can be considered as a sum of three lagged responses to solar activity, through direct, and indirect (volcanic and CO₂), influences with different lags of around 40, 800 and 1600 years. Thirdly, we find more examples of this ~1600-yr lag, associated with oceanic processes throughout the Holocene, manifested in the mineral content of SE Pacific waters, and in a carbon cycle index, CO₃, in the Southern Atlantic. Fourthly, we propose the global ocean circulation processes, that include the well known meridional overturning circulation, and the thermohaline circulation, as a global mechanism capable of explaining the lagged forcing (volcanic activity & CO₂) and continental tropical climate responses to solar activity variations. Finally, some conclusions are provided for the lagged responses of the Earth's climate system with their influences and consequences on present and future climate, and implications for climate modelling are preliminarily analyzed.