A 1750 m ice core at the South Pole was recently drilled. The oldest ice is ~55 000 years old. Since ice at the South Pole flows at 10 m per year, the ice in the core originated upstream, where the climate is different. We made measurements of the ice flow, snow accumulation, and temperature upstream. We determined the ice came from ~150 km away near the Titan Dome where the accumulation rate was similar but the temperature was colder. Our measurements improve the interpretation of the ice core.

The Asian monsoons onset has been suggested to be as early as 40 Ma, in a palaeogeographic and climatic context very different from modern conditions. We test the likeliness of an early monsoon onset through climatic modelling. Our results reveal a very arid central Asia and several regions in India, Myanmar and eastern China experiencing highly seasonal precipitations. This suggests that monsoon circulation is not paramount in triggering the highly seasonal patterns recorded in the fossils.

Planktonic foraminifera construct a shell that, post mortem, settles to the seafloor, prior to collection by Palaeoclimatologists for use as proxies. Such organisms in life are sensitive to the ambient conditions (e.g. temperature, salinity), which therefore means our proxies maybe skewed toward the ecology of organisms. Using a proxy system model, Foraminifera as Modelled Entities (FAME), we assess the potential of extracting ENSO signal from tropical Pacific planktonic foraminifera.

This study reconstructs drought chronologies of the Qing dynasty (1644–1911) based on Chinese documentary records from the REACHES database. In addition to drought records, ecological and societal records are also retrieved. Tests are performed to cross-check data and time series. Six severe drought periods are identified, and spatial patterns are revealed through multivariable analysis. Drought consequence networks are built highlighting human intervention affecting famine and social turmoil.

In the geological record of the Mediterranean Sea, we find regular, dark, organic-rich intervals. The formation of these layers has been linked to climate change caused by variations of Earth’s orbit around the Sun and the orientation of Earth’s rotational axis on timescales of tens to hundreds of thousands of years. In this study we test the hypothesis derived from the geological record with a transient model and gain new insights into the link between climate change and oceanic circulation.

To quantify the impact of major climate forcings on the Cretaceous climate, we use Earth system modelling to progressively reconstruct the Cretaceous state by changing boundary conditions one by one. Between the preindustrial and the Cretaceous simulations, the model simulates a global warming of more than 11°C. The study confirms the primary control exerted by atmospheric CO₂ on atmospheric temperatures. Palaeogeographic changes represent the second major contributor to the warming.

Understanding of the role of ocean circulation on climate is contingent on the ability to reconstruct its modes and evolution. Here, we show that earth system model simulations of the Late Cretaceous predict major changes in ocean circulation as a result of paleogeographic and gateway evolution. Comparisons of model results with available data compilations demonstrate reasonable agreement but highlight that various plausible theories of ocean circulation change coexist during this period.

We designed five experiments choosing different coccolithophore species that have been evolutionarily distinct for millions of years. If all species showed the same morphological response to an environmental driver, this could be indicative of a response pattern that is conserved over geological timescales. We found an increase in the percentage of malformed coccoliths under altered CO₂, providing evidence that this response could be used as paleo-proxy for episodes of acute CO₂ perturbations.

Droughts pose a climatic hazard that can have a profound impacts on past societies. Using documentary sources, this paper studies the occurrence and impacts of spring–summer droughts in pre-industrial England from 1200 to 1700. The impacts most relevant to human livelihood, including the agricultural and pastoral sectors of agrarian production, and public health are evaluated.

Tree rings are the main data source for climate reconstructions over the last millennium. Statistical tree-growth models have limitations that process-based models could overcome. Here, we investigate the possibility of using a process-based ecophysiological model (MAIDEN) as a complex proxy system model for palaeoclimate applications. We show its ability to simulate tree-growth index time series that can fit robustly tree-ring width observations under certain conditions.

This study explores the influence of the input data choice on spatial climate reconstructions. We compare three tree-ring-based data sets which range from small sample size, small spatial coverage and strict screening for temperature sensitivity to the opposite. We achieve the best spatial reconstruction quality by combining all available input data but rejecting records with little and uncertain climatic information and considering moisture availability as an additional growth limitation.

In this study, we present RainNet, a deep convolutional neural network for radar-based precipitation nowcasting, which was trained to predict continuous precipitation intensities at a lead time of 5 min. RainNet significantly outperformed the benchmark models at all lead times up to 60 min. Yet an undesirable property of RainNet predictions is the level of spatial smoothing. Obviously, RainNet learned an optimal level of smoothing to produce a nowcast at 5 min lead time.