The mid-Pliocene Warm Period, 3 million years ago, was the most recent interval with high greenhouse gases. By modelling the period with the same models used for future projections, we can link the past and future climates. Here we use data from the mid-Pliocene to produce a tentative result for equilibrium climate sensitivity. We show that there are considerable uncertainties that strongly influence the result, but we are optimistic that these may be reduced in the next few years.

There are observations from ocean sediment cores that during the last ice age the Laurentide Ice Sheet, which sat over North America, periodically surged. In this study we show the role that water at the base of an ice sheet plays in these surges. We show that with a more realistic representation of water drainage at the base of the ice sheet than usually used, these surges can still occur and that they are triggered by an internal ice sheet instability; no external trigger is needed.

Climate model simulations conducted in previous studies tended to underestimate the late-Pliocene higher-latitude warming suggested by proxy evidences. We explore how prescribed trace gases, ice sheets, vegetation, lakes and orography affect the Pliocene climate simulation based on a protocol of the PlioMIP Phase 2. The revised boundary forcing data lead to amplified higher-latitude warming that is qualitatively consistent with the paleoenvironment reconstructions.

One of the major difficulties in modelling palaeoclimate is constricting the boundary conditions, causing significant discrepancies between different studies. Here, a new method is presented to automate much of the process of generating the necessary geographical reconstructions. The latter can be made using various rotational frameworks and topography/bathymetry input, allowing for easy inter-comparisons and the incorporation of the latest insights from geoscientific research.

In this study we use a RCM for three different goals. Proposing a model configuration suitable for paleoclimate studies; evaluating the added value of a regional climate model for paleoclimate studies; investigating temperature evolution of the European continent during mid-to-late Holocene. Results suggest that the RCM seems to produce results in better agreement with reconstructions than its driving GCM. Simulated temperature evolution seems to be too sensitive to changes in insolation.

An Earth system model is used to explore variability in the global impacts of AMOC disruptions. The model exhibits spontaneous AMOC oscillations under particular boundary conditions, which we compare with freshwater-forced disruptions. We find that the global impacts are similar whether the AMOC disruptions are spontaneous or forced. Freshwater forcing generally amplifies the global impacts, with tropical precipitation and the stability of polar haloclines showing particular sensitivity.

Recent work shows that during the most prominent climate anomalies during the last millennium, the Medieval Climate Anomaly (ca. 950–1250) and the Little Ice Age (ca. 1450–1850), the South American monsoon system (SAMS) was drier and wetter, respectively. We investigate if this variability in the SAMS is reproduced in the latest set of climate simulations that cover these periods. Despite weak forcing, through analysis of the large-scale circulation we find this signal in the models.

This paper presents a new database of past climate proxies which aims to facilitate the distribution of data by using a user-friendly interface. Available data from the last 40 years are often fragmented, with lots of different formats, and online libraries are sometimes nonintuitive. We thus built a new dynamic web portal for data browsing, visualizing, and batch downloading of hundreds of datasets presenting a homogeneous format.

We have modelled the climate evolution from 135 to 120 kyr BP with an Earth system model to study the onset of the Last Interglacial warm period. Ice sheet changes and associated freshwater fluxes in both hemispheres constitute an important forcing in the simulations. Freshwater fluxes from the melting Antarctic ice sheet are found to lead to an oceanic cold event in the Southern Ocean as evidenced in some ocean sediment cores, which may be used to constrain the timing of ice sheet retreat.