New paper explains the ~1,500 year climate cycle on basis of astronomic variables, not CO2 – Published in Climate of the Past

By: - Climate DepotOctober 20, 2015 3:50 PM

finds the well-known~1500 year climate cycle can be explained on the basis of astronomical variables that create a “high-frequency extension of the Milankovitch precessional cycle.”

According to the authors,

“The existence of a ~ 1470 year cycle of abrupt climate change is well-established, manifesting in Bond ice-rafting debris (IRD) events, Dansgaard–Oeschger atmospheric temperature cycle, and cyclical climatic conditions precursory to increased El Niño/Southern Oscillation (ENSO) variability and intensity. This cycle is central to questions on Holocene climate stability and hence anthropogenic impacts on climate. To date no causal mechanism has been identified, although solar forcing has been previously suggested.”

“Here we show that interacting combination of astronomical variables related to Earth’s orbit may be causally related to this cycle and several associated key isotopic spectral signals. The ~ 1470 year climate cycle may thus be regarded as a high frequency extension of the Milankovitch precessional cycle, incorporating orbital, solar and lunar forcing through interaction with the tropical and anomalistic years and Earth’s rotation.”