Description: We provide global fields of simulated ocean velocity in zonal (netCDF variable UKO) and meridional (netCDF variable VKE) direction at a depth of 420 m. Six climate states are covered in the data set: 1. data set PI_mpiom_UKO_VKE_timmean_420m.nc: pre-industrial (PI) control state (representative for 1850 AD) as used in the publications by Stepanek and Lohmann (2012) and Zhang et al. (2013). The respective data is courtesy of Zhang et al. (2013) 2. data set LGM_mpiom_UKO_VKE_timmean_420m.nc: a climate state of the Last Glacial Maximum (simulation LGM-W by Zhang et al., 2013), representative for 21 kiloyears (ka) before present (BP) 3. data set Plio_mpiom_UKO_VKE_timmean_420m.nc: a climate state of the Mid-Pliocene Warm Period (simulation experiment 2 by Stepanek and Lohmann, 2012), that covers the time from 3.29 - 2.97 million years (Ma) BP 4. data set MIO_mpiom_UKO_VKE_timmean_420m.nc: a climate state representing conditions of the early to middle Miocene (23 to 15 Ma BP) including a regional bathymetry reconstruction (15 Ma) of the North Atlantic / Arctic Ocean by Ehlers and Jokat (2013) and considering 450 ppm of carbon dioxide (simulation EO450 by Stärz et al., 2017) 5. data set MioW_mpiom_UKO_VKE_timmean_420m.nc: a climate state representing conditions of the early to middle Miocene (23 to 15 Ma BP) including a regional bathymetry reconstruction (15 Ma) of the Weddell Sea (Huang et al., 2014) and considering 450 ppm of carbon dioxide in the atmosphere (simulation MIOW_450 by Huang et al., 2017) 6. data set MioW_PIS_mpiom_UKO_VKE_timmean_420m.nc: a climate state similar to 5. but with PI (278 ppm) carbon dioxide concentration and prescribed modern ice sheets (simulation MIOW_PIS by Huang et al., 2017) All data sets represent climatological annual averages over a time period of 100 years. The oceanography is based on climate simulations performed with the Community Earth System Models (COSMOS) that consist of the atmosphere general circulation model ECHAM5 (Roeckner et al., 2003), internally coupled to the land surface and terrestrial carbon cycle model JSBACH (Raddatz et al., 2007) in T31 resolution (3.75°x3.75°) with 19 vertical levels on a hybrid sigma-pressure coordinate, and the ocean general circulation model MPIOM (Marsland et al., 2003) on a bipolar curvilinear GR30 grid with a formal resolution of 3.0°x1.8° and 40 z-coordinate levels. Exchange of momentum, mass, and energy between the atmosphere and ocean domain is enabled via the OASIS3 coupler (Valcke et al., 2003). For all simulations, ocean characteristics (including sea ice) and properties of atmosphere and land (including the land carbon cycle and dynamic vegetation) are computed based on the prescribed climate forcing (concentration of atmospheric trace gases, configuration of the Earth's orbit) and boundary conditions (land surface elevation, ice sheets, ocean bathymetry, and land sea mask). For details of the utilized boundary conditions and climate forcing refer to the original publications describing the data (Stepanek and Lohmann, 2012; Zhang et al., 2013; Huang et al., 2017; Stärz et al., 2017). In case of analyzing velocities of the Arctic Ocean, note that for few grid cells in the northernmost data row (89.5°N), between 280°E and 293°E, there is a data artifact in variable VKE. This artifact is a side effect of rotating and interpolatiing velocities from the curvilinear model grid to a standard NSWE coordinate system; this artifact has not been removed from the data sets.

Description: In this manuscript we describe the experimental procedure employed at the Alfred Wegener Institute in Germany in the preparation of the simulations for the Pliocene Model Intercomparison Project (PlioMIP). We present a description of the utilized Community Earth System Models (COSMOS, version: COSMOS-landveg r2413, 2009) and document the procedures that we applied to transfer the Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project mid-Pliocene reconstruction into model forcing fields. The model setup and spin-up procedure are described for both the paleo- and preindustrial (PI) time slices of PlioMIP experiments 1 and 2, and general results that depict the performance of our model setup for mid-Pliocene conditions are presented. The mid-Pliocene, as simulated with our COSMOS setup and PRISM boundary conditions, is both warmer and wetter in the global mean than the PI. The globally averaged annual mean surface air temperature in the mid-Pliocene standalone atmosphere (fully coupled atmosphere-ocean) simulation is 17.35 °C (17.82 °C), which implies a warming of 2.23 °C (3.40 °C) relative to the respective PI control simulation.

Description: We provide a climatic data set of the history of annual mean surface air temperature (SAT) over the last 1,000,000 years. The SAT (i.e. the temperature at 2 meter height above the ground) has been simulated by means of the Community Earth System Models (COSMOS, consisting of ECHAM5, JSBACH, MPIOM). These have been exposed to the solution of elements of the Earth's orbit around the sun (eccentricity, obliquity, longitude of the perihelion) by Laskar et al. (2004) for the last 1,000,000 years. Towards practical feasibility of the climate simulation, the orbital forcing has been accelerated by a factor of 100 based on the method described by Lorenz and Lohmann (2004). A detailed description of the COSMOS' application in the framework of paleoclimate can be found, for example, in the publication by Stepanek and Lohmann (2012).

Description: In this data set we publish the simulated global annual mean precipitation over a time period of 50 years retrieved from equilibrium climate simulations for Pre-Industrial (PI) and 8 ka BP (HOL6) and utilized in the publication by Guagnin et al. (2016). The climate data has been produced with COSMOS (ECHAM5/JSBACH/MPIOM/OASIS3), utilized at a resolution of T31 in the atmosphere (19 hybrid sigma-pressure levels) and a resolution of GR30 (bipolar orthogonal curvilinear grid, formal resolution of ~3.0°x1.8°) in the ocean (40 z-coordinate levels). The only differences between the model setups of simulations PI and HOL6 are the settings of the Earth's orbital parameters and the atmosphere's constituents of trace gases, that have been set to the values representative for the respective time slice (see Table 1 of Guagnin et al. (2016) for details).

Description: The Pliocene Epoch (~2.6–5.3 million years ago, Ma) was characterized by a warmer than present climate with smaller Northern Hemisphere ice sheets, and therefore offers an example of a climate system in long-term equilibrium with current or predicted near-future carbon dioxide concentrations. The end of the Pliocene (~2.6 Ma) is marked by further ice-sheet expansion and intensification of glacial (cold) stages, referred to as the "intensification of Northern Hemisphere Glaciation" (iNHG). Here we present the data used to assess the spatial and temporal variability of ocean temperatures and ice-volume indicators through the late Pliocene and early Pleistocene (from 3.3 to 2.4 Ma) to determine the character of this climate transition. The data come from the Atlantic, Pacific, Indian and Southern Ocean, as well as some marginal seas. Here we present the synthesized alkenone sea-surface temperature, Mg/Ca sea-surface temperature, planktonic foraminifera d18O and benthic foraminifera d18O data which were used in our synthesis. Although the original data sets are largely published, here we present the alkenone SST records calculated using the BAYSPLINE calibration where these were not part of the original publication; the Mg/Ca-SST records where we revised the absolute SSTs; any data sets where we revised the age model.