Accurate quantification of the millennial-scale mass balance of the Greenland ice sheet (GrIS) and its contribution to global sea-level rise remain challenging because of sparse in situ observations in key regions. Glacial isostatic adjustment (GIA) is the ongoing response of the solid Earth to ice and ocean load changes occurring since the Last Glacial Maximum (LGM; ~21 thousand years ago) and may be used to constrain the GrIS deglaciation history.

Large-scale biomass plantations (BPs) are often considered a feasible and safe climate engineering proposal for extracting carbon from the atmosphere and, thereby, reducing global mean temperatures. However, the capacity of such terrestrial carbon dioxide removal (tCDR) strategies and their larger Earth system impacts remain to be comprehensively studied—even more so under higher carbon emissions and progressing climate change.

California has experienced a dry 21st century capped by severe drought from 2012 through 2015 prompting questions about hydroclimatic sensitivity to anthropogenic climate change and implications for the future. We address these questions using a Holocene lake sediment record of hydrologic change from the Sierra Nevada Mountains coupled with marine sediment records from the Pacific. These data provide evidence of a persistent relationship between past climate warming, Pacific sea surface temperature (SST) shifts and centennial to millennial episodes of California aridity.

We present a 3.2 Myr record of stable isotopes and physical properties at IODP Site U1308 (reoccupation of DSDP Site 609) located within the ice-rafted detritus (IRD) belt of the North Atlantic. We compare the isotope and lithological proxies at Site U1308 with other North Atlantic records (e.g., sites 982, 607/U1313, and U1304) to reconstruct the history of orbital and millennial-scale climate variability during the Quaternary.

Original Source

The year 1980 has often been used as a benchmark for the return of Antarctic ozone to conditions assumed to be unaffected by emissions of ozone depleting substances (ODSs), implying that anthropogenic ozone depletion in Antarctica started around 1980. Here, the extent of anthropogenically-driven Antarctic ozone depletion prior to 1980 is examined using output from transient Chemistry-Climate Model (CCM) simulations from 1960 to 2000 with prescribed changes of ozone depleting substance concentrations in conjunction with observations.

During the Last Glacial Maximum, continental ice sheets isolated Beringia (northeast Siberia and northwest North America) from unglaciated North America. By around 15 to 14 thousand calibrated radiocarbon years before present (cal. kyr BP), glacial retreat opened an approximately 1,500-km-long corridor between the ice sheets. It remains unclear when plants and animals colonized this corridor and it became biologically viable for human migration. We obtained radiocarbon dates, pollen, macrofossils and metagenomic DNA from lake sediment cores in a bottleneck portion of the corridor.

The high Arctic archipelagos around the globe are among the most strongly glacierized landscapes on Earth apart from the Greenland and Antarctic ice sheets. Over the past decades, the mass losses from land ice in the high Arctic regions have contributed substantially to global sea level rise. Among these regions, the archipelago of Svalbard showed the smallest mass losses. However, this could change in the coming decades, as Svalbard is expected to be exposed to strong climate warming over the 21st century.

The evolution of industrial-era warming across the continents and oceans provides a context for future climate change and is important for determining climate sensitivity and the processes that control regional warming. Here we use post-AD 1500 palaeoclimate records to show that sustained industrial-era warming of the tropical oceans first developed during the mid-nineteenth century and was nearly synchronous with Northern Hemisphere continental warming.