The Eemian (last interglacial, 130-115 ka) was likely the warmest of all interglacials of the last 800 ka, with summer Arctic temperatures 3-5°C above present. Here, we present improved Eemian climate records from central Greenland, reconstructed from the base of the Greenland Ice Sheet Project 2 (GISP2) ice core. Our record comes from clean, stratigraphically disturbed, and isotopically warm ice from 2,750 to 3,040 m depth. N of N 2 , and total air content for samples dating discontinuously from 128 to 115 ka indicate a warming of ∼6°C between 127-121 ka, and a similar elevation history between GISP2 and NEEM. The reconstructed climate and elevation histories are compared with an ensemble of coupled climate-ice-sheet model simulations of the Greenland ice sheet. Those most consistent with the reconstructed temperatures indicate that the Greenland ice sheet contributed 5.1 m (4.1-6.2 m, 95% credible interval) to global eustatic sea level toward the end of the Eemian. Greenland likely did not contribute to anomalously high sea levels at ∼127 ka, or to a rapid jump in sea level at ∼120 ka. However, several unexplained discrepancies remain between the inferred and simulated histories of temperature and accumulation rate at GISP2 and NEEM, as well as between the climatic reconstructions themselves.Greenland ice sheet | last interglacial | ice cores | sea level rise D uring the last interglacial (Eemian, 130-115 ka), Arctic summer temperatures were 3-5°C warmer than today (1), and peak global eustatic sea level was likely 6-9 m higher than the present (2). In the next century, due to anthropogenic emissions of greenhouse gases, we face a similar temperature scenario with 2-6°C of northern hemispheric polar warming (3), and a likely initial sea level rise (by 2100) of 0.3-1.0 m (4), with higher, but uncertain, levels beyond. Certainly there are important differences between the warming and sea level change observed during the last climatic warm period and future projections, notably the rate at which warming is expected to occur and its spatial pattern. Nevertheless, the Eemian history of the Greenland ice sheet (GrIS) serves as an essential test bed for understanding changes in ice sheets and sea level rise in response to rising global temperatures.Ice sheet modeling studies have estimated a wide range of GrIS contributions to sea level during the Eemian, with simulations producing 0.4-5.5 m of equivalent sea level rise above the present datum (5).

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The long-term stability of the Greenland Ice Sheet (GIS) is an important issue in our understanding of the climate system. Limited data suggest that the northern and southern sections extend well back into the Pleistocene, but most age constraints do not definitively date the ice. Here, we reexamine the GRIP and Dye-3 ice cores to provide direct ice core observations as to whether the GIS survived previous interglacials known to be warmer (~130 ka) or longer (~430 ka) than that of the present interglacial. We present geochemical analyses of the basal ice from Dye-3 (1991-2035 m) and GRIP (3020-3026 m) that characterize and date the ice. We analyzed the elemental and isotopic composition of O 2 , N 2 , and Ar, of trapped air in these two cores to assess the origin of trapped gases in silty ice. Dating of the trapped air was then achieved by measuring the paleoatmospheric  40 Ar/ 38 Ar and the 17 O anomaly (17 ) of O 2. The resulting age is a lower limit because the trapped air maybe contaminated with crustal radiogenic 40 Ar. The oldest average age of replicates measured at various depths is 970 ± 140 ka for the GRIP ice core and 400 ka ± 170 ka for Dye-3. 17  data from Dye-3 also argue strongly that basal ice in this core predates the Eemian. This confirms that the Greenland Ice Sheet did not completely melt at Southern Greenland during the last interglacial, nor did it completely melt at Summit Greenland during the unusually long interglacial ~ 430 kyr before present.

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