Coupled climate model simulation of Holocene cooling events: oceanic feedback amplifies solar forcing
نویسنده
چکیده
The coupled global atmosphere-ocean-vegetation model ECBilt-CLIO-VECODE is used to perform transient simulations of the last 9000 years, forced by variations in orbital parameters, atmospheric greenhouse gas concentrations and total solar irradiance (TSI). The objective is to study the impact of decadal-to-centennial scale TSI variations on Holocene climate variability. The simulations show that negative TSI anomalies increase the probability of temporary relocations of the site with deepwater formation in the Nordic Seas, causing an expansion of sea ice that produces additional cooling. The consequence is a characteristic climatic anomaly pattern with cooling over most of the North Atlantic region that is consistent with proxy evidence for Holocene cold phases. Our results thus suggest that the ocean is able to play an important role in amplifying centennial-scale climate variability.
منابع مشابه
Simulation of Holocene cooling events
Coupled climate model simulation of Holocene cooling events: solar forcing triggers oceanic feedback H. Renssen, H. Goosse, and R. Muscheler Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands Institut d’Astronomie et de Géophysique G. Lemaı̂tre, Université Catholique de Louvain, 2 Chemin du Cyclotron, 1348 Louvain-la-Neuve, Bel...
متن کاملContrasting trends in North Atlantic deep-water formation in the Labrador Sea and Nordic Seas during the Holocene
[1] The Holocene North Atlantic deep-water formation is studied in a 9,000-year long simulation with a coupled climate model of intermediate complexity, forced by changes in orbital forcing and atmospheric trace gas concentrations. During the experiment, deep-water formation in the Nordic Seas is reduced due to an enhanced influx of sea ice from the Central Arctic, decreasing both surface salin...
متن کاملClimate Forcing during the Holocene
The role of several important factors that have played a role in Holocene climate change is examined. These forcing factors operate on different time-scales: lower frequency (millennial-scale) climate changes associated with orbital forcing, century-scale variability associated with solar forcing, and annualto decadal-scale variability associated with volcanic forcing. Feedbacks within the clim...
متن کاملENSO in the Mid-Holocene according to CSM and HadCM3
The offline linearized ocean–atmosphere model (LOAM), which was developed to quantify the impact of the climatological mean state on the variability of the El Ni~ no–Southern Oscillation (ENSO), is used to illuminate why ENSO changed between the modern-day and early/mid-Holocene simulations in two climate modeling studies using the NCAR Climate System Model (CSM) and the Hadley Centre Coupled M...
متن کاملInfluence of orbital forcing and solar activity on water isotopes in precipitation during the mid- and late Holocene
In this study we investigate the impact of midand late Holocene orbital forcing and solar activity on variations of the oxygen isotopic composition in precipitation. The investigation is motivated by a recently published speleothem δ18O record from the well-monitored Bunker Cave in Germany. The record reveals some high variability on multicentennial to millennial scales that does not linearly c...
متن کامل