Oceanic Mechanisms for Amplification of the 23,000-Year Ice-Volume Cycle

摘要: Situated adjacent to the largest Northern Hemispher ice sheets of ages, mid-latitude North Atlantic Ocean has an important role in earth's climate history. It provides a significant local source moisture for atmosphere and continents, forms corridor that guides moisture-bearing storms northward from low latitudes, at times makes direct contact along its shorelines with continental masses. Evidence major ice-ocean-air interactions involving during last 250,000 years is summarized. Outflow icebergs meltwater initially driven by summer insolation over affects midlatitude ocean temperatures, heat storage, winter sea-ice extent, global sea level. These oceanic responses turn influence flux back sheets, as well ablation land calving. Spectral data indicate sea-level feedbacks, part controlled glacial melt products, amplify Milankovitch (insolation) forcing volumetrically dominant 23,000-year precessional cycle.