Description of the Earth system model of intermediate complexity LOVECLIM version 1.2

Abstract

Abstract. The main characteristics of the new version 1.2 of the three-dimensional Earth system model of intermediate complexity LOVECLIM are briefly described. LOVECLIM 1.2 includes representations of the atmosphere, the ocean and sea ice, the land surface (including vegetation), the ice sheets, the icebergs and the carbon cycle. The atmospheric component is ECBilt2, a T21, 3-level quasi-geostrophic model. The oceanic component is CLIO3, which is made up of an ocean general circulation model coupled to a comprehensive thermodynamic-dynamic sea-ice model. Its horizontal resolution is 3° by 3°, and there are 20 levels in the ocean. ECBilt-CLIO is coupled to VECODE, a vegetation model that simulates the dynamics of two main terrestrial plant functional types, trees and grasses, as well as desert. VECODE also simulates the evolution of the carbon cycle over land while the oceanic carbon cycle is represented in LOCH, a comprehensive model that takes into account both the solubility and biological pumps. The ice sheet component AGISM is made up of a three-dimensional thermomechanical model of the ice sheet flow, a visco-elastic bedrock model and a model of the mass balance at the ice-atmosphere and ice ocean interfaces. For both the Greenland and Antarctic ice sheets, calculations are made on a 10 km by 10 km resolution grid with 31 sigma levels. LOVECLIM 1.2 reproduces well the major characteristics of the observed climate both for present-day conditions and for key past periods such as the last millennium, the mid-Holocene and the Last Glacial Maximum. However, despite some improvements compared to earlier versions, some biases are still present in the model. The most serious ones are mainly located at low latitudes with an overestimation of the temperature there, a too symmetric distribution of precipitation between the two hemispheres, an overestimation of precipitation and vegetation cover in the subtropics. In addition, the atmospheric circulation is too weak. The model also tends to underestimate the surface temperature changes (mainly at low latitudes) and to overestimate the ocean heat uptake observed over the last decades.

Analysis of a fragmentary diatom record from Lake Van (Turkey) reveals substantial lake-level variability during previous interglacials MIS7 and MIS5e

“…According to a hydroclimate reconstruction (see PC1 in Fig. 5) using a suite of proxy records sensitive to lake level fluctuations of Lake Van, and transient model simulations from an Earth System model LOVECLIM (Goosse et al 2010), higher SSTs in the North Atlantic correspond to increased precipitation in the eastern Mediterranean (Stockhecke et al 2016). Our results therefore support the correspondence of climate linkages between the North Atlantic and eastern Mediterranean.…”

Abrupt changes in the southern extent of North Atlantic Deep Water during Dansgaard–Oeschger events

“…The performance of the LOVECLIM model has been successfully validated for pre-industrial conditions and key intervals in the past 56,57 . An equilibrium spin-up simulation was performed with an atmospheric CO 2 content of 207.5 ppmv, orbital forcing and an estimated ice sheet extent and topography corresponding to 50 ka BP 58 .…”

Orbital Asian summer monsoon dynamics revealed using an isotope-enabled global climate model

“…We used the iLOVECLIM model, a derivative of the LOVECLIM model 30 because of its computing efficiency. Although our model experiences some weaknesses caused by its spatial resolution and simplified convective physics (in particular, the summer precipitation is underestimated and the low-level geopotential ridge over the North Pacific is shifted northward 10 degrees in latitude compared with observations), LOVECLIM was previously successfully applied in the Asian monsoon region for qualitative assessment of the connections between ice sheets and sub-tropical dynamics 31 and reconstruction of past monsoonal precipitation 32,33 .…”