The Middle Eocene Climatic Optimum (MECO) was a global warming event that took place 40 Myr ago and lasted ca. 500 kyr, inducing physical, chemical, and biotic changes on the Earth. We use stable isotopes to identify the MECO in the Eocene deltaic deposits of the Southern Pyrenees. Our findings reveal enhanced deltaic progradation during the MECO, pointing to the important impact of global warming on fluvial sediment transport with implications for the consequences of current climate change.

Oxygen isotopes are used to date marine sediments via similar large-scale ocean patterns over glacial cycles. However, the Arctic Ocean exhibits a different isotope pattern, creating uncertainty in the timing of past Arctic climate change. We find that the Arctic Ocean experienced large local oxygen isotope changes over glacial cycles. We attribute this to a breakdown of stratification during ice ages that allowed for a unique low isotope value to characterize the ice age Arctic Ocean.

It is unclear how different components of the global atmospheric circulation, such as the El Niño effect, respond to large-scale climate change. We present a new ice core gas proxy, called krypton-86 excess, that reflects past storminess in Antarctica. We present data from 11 ice cores that suggest the new proxy works. We present a reconstruction of changes in West Antarctic storminess over the last 24 000 years and suggest these are caused by north–south movement of the tropical rain belt.

We produced a 1.5-million-year-long history of climate change at International Ocean Discovery Program Site U1385 of the Iberian margin, a well-known location for rapidly accumulating sediments on the seafloor. Our record demonstrates that longer-term orbital changes in Earth's climate were persistently overprinted by abrupt millennial-to-centennial climate variability. The occurrence of abrupt climate change is modulated by the slower variations in Earth's orbit and climate background state.

Increasing the vegetation cover over mid-Holcocene North Africa expands the West African monsoon ∼ 4–5° further north. This northward shift of monsoonal precipitation is caused by interactions of the land surface with large-scale monsoon circulation and the coupling of soil moisture to precipitation. We highlight the importance of considering not only how soil moisture influences precipitation but also how different precipitation characteristics alter the soil hydrology via runoff generation.

Based on proxy data and modeling, the Arctic temperature has an asymmetric cooling trend with more cooling over the Atlantic Arctic than the Pacific Arctic during the Holocene, dominated by orbital forcing. There is a seasonal difference in the asymmetric cooling trend, which is dominated by the DJF (December, January, and February) temperature variability. The Arctic dipole mode of sea level pressure and sea ice play a major role in asymmetric temperature changes.

Year-to-year variations in the weather conditions over the Indian Ocean have important consequences for the substantial fraction of the Earth's population that live near it. This work looks at how these variations respond to climate change – both past and future. The models rarely agree, suggesting a weak, uncertain response to climate change.

Climate reconstructions give insights into monthly and seasonal climate variability of the past few hundred years. However, to understand past extreme weather events and to relate them to impacts, for example to periods of extreme floods, reconstructions on a daily timescale are needed. Here, we present a reconstruction of 258 years of high-resolution daily temperature and precipitation fields for Switzerland covering the period 1763 to 2020, which is based on instrumental measurements.

The sensitivity of climate to the height changes of the East Antarctic ice sheet (EAIS) during the mid-Pliocene has been assessed using the HadCM3 model. The results show that the height reduction of the EAIS leads to a warmer and wetter East Antarctica. However, unintuitively, both the surface air temperature and the sea surface temperature decrease over the rest of the globe. These findings could provide insights into future changes caused by warming-induced decay of the Antarctic ice sheet.

Warm climates of the Pliocene (~ 3 million years ago) are similar to projections of the near future. We find elevated concentrations of atmospheric carbon dioxide to be the most important forcing for driving changes in Pliocene surface air temperature, sea surface temperature, and precipitation. However, changes caused by the nature of Pliocene ice sheets and orography are also important, affecting the extent to which we can use the Pliocene as an analogue for our warmer future.