The pattern of Earth’s ice age cycles shifted around a million years ago, becoming more extreme and longer in duration. Multiple projects are underway to obtain an Antarctic ice core that covers this time period, as ice cores contain important clues to why the transition happened. To make sure the ice is old enough at the bottom, we demonstrate how to use new technology to quickly measure dust patterns in the ice and compare them to dust in deep-ocean sediments whose ages are known.

The purpose of this study is to recognise the nature of the climate in historical times (second half of 18th century) in Greenland. Such knowledge is important for validating Greenland temperature reconstructions based on both modelling works and various proxies. The two unique series of old meteorological observations from Greenland we used indicated that temperature in the study period was comparable to that of the early 20th-century Arctic warming but lower than that of the present day.

A locally financed project aims at studying former mountain glaciers at the Alps–Dinarides junction, and a study was conducted about a currently ice-free plateau that bears evidence of past glaciation. The study combines geomorphological estimates of the ice field extent with computer simulations of the ice field. Although the shape of the past ice field cannot be reconstructed exactly, the computer reconstruction helps us identify past climatic conditions that enabled the ice field's growth.

Ensemble simulations of the climate and ice sheets of the Last Glacial Maximum (LGM) are performed with a new coupled climate–ice sheet model. Results show a strong sensitivity of the North American ice sheet to the albedo scheme, while the Greenland ice sheet appeared more sensitive to basal sliding schemes. Our result implies a potential connection between the North American ice sheet at the LGM and the future Greenland ice sheet through the albedo scheme.

We provide detailed translations of some abnormal meteorological conditions in 43–33 BCE described in Chinese historical documents possibly related to the Okmok volcanic eruption in Alaska in early 43 BCE. The cold summer record and the abnormal color and low brightness of the sun point to the clear link to the volcanic impact. The reported duration for the visual condition of the sun to return to normal should be useful for researchers modeling the volcanic impact on climate.

We present a reconstruction of permafrost and snow cover on the British Isles for the Younger Dryas period, a time of extremely cold winters that happened approximately 12 000 years ago. Our results indicate that seasonal sea ice in the North Atlantic was most likely a crucial factor to explain the observed climate shifts during this time.

The opening of the South Atlantic Ocean, starting ~ 140 million years ago, had the potential to influence the global carbon cycle and climate trends. We use 36 climate model experiments to simulate the evolution of ocean circulation in this narrow basin. We test different combinations of palaeogeographic and atmospheric CO₂ reconstructions with geochemical data to not only quantify the influence of individual processes on ocean circulation but also to find nonlinear interactions between them.

During the last glacial period, the Patagonian Ice Sheet grew along the southern Andes, leaving marks on the landscape showing its former extents and timing. We use paleoclimate and ice sheet models to replicate its glacial history. We find that errors in the model-based ice sheet are likely induced by imprecise reconstructions of air temperature due to poorly resolved Andean topography in global climate models, while a fitting regional climate history is only captured by local sediment records.

This study employs Haar fluctuations to analyse global atmospheric variability over the Last Glacial Cycle, revealing a latitudinal dependency in the transition from macroweather to climate regimes. Findings indicate faster synchronisation between poles and lower latitudes, supporting the pivotal role of poles as climate change drivers.

We close the terrestrial water cycle across the Sahara and Sahel by integrating a new endorheic-lake model into a climate model. A factor analysis of mid-Holocene simulations shows that both dynamic lakes and dynamic vegetation individually contribute to a precipitation increase over northern Africa that is collectively greater than that caused by the interaction between lake and vegetation dynamics. Thus, the lake–vegetation interaction causes a relative drying response across the entire Sahel.

This study is motivated by the current anthropogenic-warming-forced transition in regional hydroclimate. We use observations and model simulations during the Paleocene–Eocene Thermal Maximum (PETM) to constrain the regional/local hydroclimate response. Our findings, based on multiple observational evidence within the context of model output, suggest a transition toward greater aridity and precipitation extremes in central California during the PETM.

This study reviews the current state of knowledge regarding the Oligocene icehouse climate. We extend an existing marine climate proxy data compilation and present a new compilation and analysis of terrestrial plant assemblages to assess long-term climate trends and variability. Our data–climate model comparison reinforces the notion that models underestimate polar amplification of Oligocene climates, and we identify potential future research directions.

Although significant progress in Early Jurassic cyclostratigraphy has been made in the last few decades, fewer studies have focused on the climatic and environmental impact of orbital cycles on the sedimentary record. This study presents an original orbitally modulated depositional model, which provides new insight into the formation of orbitally modulated organic-rich calcareous hemipelagic rhythmites accumulated in early Pliensbachian times in the northern Iberian palaeomargin.

Tree rings of Qinghai spruce are a good record of regional climate change. The influence of the East Asian summer monsoon (EASM) and westerlies on regional dry–wet climate changes is characterized by spatiotemporal heterogeneity. The most dramatic interplay between EASM and westerlies is observed in the Helan Mountains. Regional climate changes around the Changling Mountains are most influenced by EASM and around Dongda Mountain most influenced by westerlies.