Polar climate variability during the Holocene as archived in ice core water isotopes

Understanding natural climate variability, its fluctuations throughout the Holocene, and its dependency on the mean climate state can provide valuable insights into driving mechanisms and potentially allow for a better prediction of a plausible range of future climates. However, polar climate variability and its changes remain uncertain due to a lack of thorough analysis across the Holocene. Ice core water isotope records are a temperature proxy which covers both high resolutions as well as long timescales and thus enable us to resolve variability changes across a large range of frequencies. By consolidating a multitude of such records from Greenland and Antarctica and using our knowledge how the ice-core signal is recorded, we distinguish signal from noise in the spectral domain. Based on this, we examine spatial and temporal changes of the polar climate signal variability, its relationships to earth system processes and its representation in climate models.