Holocene experiment with coupled atmosphere-ocean-model ECHAM5/MPI-OM

DOI

Changes in the Earth's orbit lead to changes in the seasonal and meridional distribution of insolation. We quantify the influence of orbitally induced changes on the seasonal temperature cycle in a transient simulation of the last 6000 years – from the mid-Holocene to today – using a coupled atmosphere-ocean general circulation model (ECHAM5/MPI-OM) including a land surface model (JSBACH).The seasonal temperature cycle responds directly to the insolation changes almost everywhere. In the Northern Hemisphere, its amplitude decreases according to an increase in winter insolation and a decrease in summer insolation. In the Southern Hemisphere, the opposite is true.Over the Arctic Ocean, decreasing summer insolation leads to an increase in sea-ice cover. The insulating effect of sea ice between the ocean and the atmosphere leads to decreasing heat flux and favors more "continental" conditions over the Arctic Ocean in winter, resulting in strongly decreasing temperatures. Consequently, there are two competing effects: the direct response to insolation changes and a sea-ice insulation effect. The sea-ice insulation effect is stronger, and thus an increase in the amplitude of the seasonal temperature cycle over the Arctic Ocean occurs. This increase is strongest over the Barents Shelf and influences the temperature response over northern Europe.We compare our modeled seasonal temperatures over Europe to paleo reconstructions. We find better agreements in winter temperatures than in summer temperatures and better agreements in northern Europe than in southern Europe, since the model does not reproduce the southern European Holocene summer cooling inferred from the paleo reconstructions. The temperature reconstructions for northern Europe support the notion of the influence of the sea-ice insulation effect on the evolution of the seasonal temperature cycle.

The data consist of snap-shots taken every 50-years over the simulation period of 6.000 years.

Supplement to: Fischer, Nils; Jungclaus, Johann H (2011): Evolution of the seasonal temperature cycle in a transient Holocene simulation: orbital forcing and sea-ice. Climate of the Past, 7, 1139-1148

Identifier
DOI https://doi.org/10.1594/PANGAEA.773607
Related Identifier https://doi.org/10.5194/cp-7-1139-2011
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.773607
Provenance
Creator Fischer, Nils; Jungclaus, Johann H
Publisher PANGAEA
Publication Year 2012
Funding Reference German Research Foundation https://doi.org/10.13039/501100001659 Crossref Funder ID 25575884 https://gepris.dfg.de/gepris/projekt/25575884 Integrierte Analyse zwischeneiszeitlicher Klimadynamik
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 77 data points
Discipline Earth System Research