Changes in solar constant over an 11 yr cycle suggest a certain, but limited, degree of solar forcing of climate. The high-resolution climate (oxygen isotope) record of the Greenland GISP2 (Greenland Ice Sheet Project 2) ice core has been analyzed for solar (and volcanic) influences. The atmospheric 14C record is used as a proxy of solar change and compared to the oxygen isotope profile in the GISP2 ice core. An annual oxygen isotope profile is derived from centimeter-scale isotope measurements available for the post-A.D. 818 interval. Associated extreme summer and winter isotope ratios were found to yield similar climate information over the last millennium. The detailed record of volcanic aerosols, converted to optical depth and volcanic explosivity change, was also compared to the isotope record and the oxygen isotope response calibrated to short-term volcanic influences on climate. This calibration shows that century-scale volcanic modulation of the GISP2 oxygen isotope record can be neglected in our analysis of solar forcing. The timing, estimated order of temperature change, and phase lag of several maxima in 14C and minima in18O are suggestive of a solar component to the forcing of Greenland climate over the current millennium. The fractional climate response of the cold interval associated with the Maunder sunspot minimum (and 14C maximum), as well as the Medieval Warm Period and Little Ice Age temperature trend of the past millennium, are compatible with solar climate forcing, with an order of magnitude of solar constant change of ∼0.3%. Even though solar forcing of climate for the current millennium is a reasonable hypothesis, for the rest of the Holocene the century-scale events are more frequent in the oxygen isotope record than in the 14C record and a significant correlation is absent. For this interval, oceanic/atmospheric circulation forcing of climate may dominate. Solar forcing during the surprisingly strong 1470 yr climate cycle of the 11,000–75,000 yr B.P. interval is rather hypothetical.

Minimal and maximal models of Late Pleistocene Glaciation on the Tibetan Plateau are considered. The large ice sheet models indicate that disintegration of the ice sheet could have contributed up to 7 mm/yr of present vertical uplift and 2 mm/yr of horizontal extension. The former value can account for more than 50% of the observed uplift in central Tibet. The peak free-air gravity anomaly arising from the deglaciation would be around −5.4 mGal. In contrast, the smaller ice sheet models do not contribute significantly to the signals of present uplift and gravity anomalies. Modern geodetic measurements therefore have the potential to constrain the Late Pleistocene glaciation of the Tibetan Plateau. Assuming a large ice sheet over the Tibetan Plateau, the disintegration can contribute up to 6 m of eustatic sea-level rise.

The study of glacial evidence in the Gran Sasso Massif of the Central Apennines, Italy, has allowed the last maximum advance and the subsequent stadial phases to be dated and the mean annual temperature and quantity of precipitation in the form of snow to be assessed for a number of periods. The glaciers probably reached their maximum extension (Campo Imperatore Stade) ca. 22,600 14C yr B.P. and started to retreat ca. 21,000 yr B.P., leaving behind three recessional moraines. After a first interstade (Fornaca Interstade), the Fontari Stade appears to have taken place shortly after 16,000 yr ago. Ca. 15,000 yr ago the glacier started retreating, leaving behind four more recessional moraines. An interstade (Venacquaro Interstade) preceded the Mount Aquila Stade, datable at ca. 11,000 yr B.P. A strong correlation is evident between the glacial phases on land and the isotopic variations in cores from the Tyrrhenian Sea.

The application of both thermoluminescence and infrared stimulated luminescence dating to the extensively studied “classical” Hungarian loess/paleosol sequences from Basaharc, Mende, and Paks provides a reliable chronological framework and climatostratigraphic reconstruction for the last interglacial/glacial cycle. Based on this combined luminescence dating study a new chronology is proposed for the “Young Loess” in Hungary. Luminescence dating suggests that the loess below the MF2 horizon formed during the penultimate glaciation. The MF1 horizon probably formed during an interstade within oxygen isotope stage 3. For the youngest loess, overlying MF1, a very high accumulation rate was determined. Large time gaps occur above MF2 and MF1, indicating that most of the record of the last glaciation is missing in the standard sections at Basaharc, Mende, and Paks. Either large discontinuities or a very low accumulation rate occurred in all three type sections during the soil-forming periods. High-resolution studies of climatic proxies using this combined luminescence dating approach provide a reliable chronological framework for loess and loess derivatives of the last glacial cycle in Hungary, although a precise and complete chronostratigraphic reconstruction cannot be achieved from the incomplete records found at these sites.

Chemical analyses of the acid-soluble and clay-size fractions of sediment samples (1500-yr resolution) reveal oscillations of lake salinity and of glacial advances in core OL-92 back to 155,000 yr B.P. Relatively saline conditions are indicated by the abundance of carbonate and smectite (both pedogenic and authigenic), reflected by Ca, Sr, and Mg in the acid-soluble suite, and by Cs2O, excess MgO, and LOI (loss on ignition) in the clay-size fraction. Rock flour produced during glacial advances is represented by the abundance of detrital plagioclase and biotite in the clay-size fraction, the ratio of which remains essentially constant over the entire time span. These phases are quantitatively represented by Na2O, TiO2, Ba, and Mn in the clay fraction. The rock-flour record indicates two major ice-advances during the penultimate glacial cycle corresponding to marine isotope stage (MIS) 6, no major advances during the last interglaciation (entire MIS 5), and three major advances during the last glacial cycle (MIS 2, 3, and 4). The ages of the latter three correspond rather well to36Cl dates reported for Sierra Nevada moraines. The onset of the last interglaciation is shown by abrupt increases in authigenic CaCO3and an abrupt decrease in rock flour, at about 118,000 yr B.P. according to our time scale. In contrast, the boundary appears to be gradual in the δ18O record in which the change from light to heavy values begins at about 140,000 yrs B.P. The exact position of the termination, therefore, may be proxy-dependent. Conditions of high carbonate and low rock flour prevailed during the entire period from 118,000 yr B.P. until the glacial advance at 53,000 yr B.P. signaled the end of this long interglaciation.

Seven boulders measuring 100 to 1000 m3 are scattered along the coastal ridge of north Eleuthera. Some are situated on ridge crests up to 20 m above present sea level. The boulders were probably deposited during oxygen-isotope substage 5e or 5d, as shown by their stratigraphic setting and by amino acid racemization ratios. D-alloisoleucine/L-isoleucine ratios were determined for land snails, and oolite of both marine and eolian origin was associated with the boulders. Like the boulders, the probable source rocks exposed in the adjacent cliffs are composed of marine and eolian limestone of oolitic and peloidal composition. The source beds are correlated with stage 9 or 11. The largest boulder is about 10 times the size of the largest Holocene ones moved by waves in the area. Tsunamis are a reasonable possibility as a transporting mechanism of the Pleistocene boulders. However, if deposited instead by storms during the last interglaciation, the storms were of much greater intensity than those occurring in the region during the late Holocene.

Four pollen diagrams from Minorca (Balearic Islands) have been correlated with other previously studied sequences from Majorca and Minorca to define a Holocene landscape sequence for the region from 8000 yr B.P. to the present. The lower part of the pollen diagrams reflects a climatic phase with more rain and less-marked seasonality than today. Significant quantities of Corylus, Buxus, and mesophilous taxa are found. In the middle part, between 5000 and 4000 yr B.P., a strong change is recorded in composition and structure of the vegetational landscape, with vegetation appearing that was adapted to Mediterranean conditions. This episode coincided with the first human colonization of the island and also with a widespread climatic change in the western Mediterranean region. The change in taxa was complex and some sclerophyllous taxa such Olea played an important role in the transformation of the landscape physiognomy from the mid-Holocene until the present. Although human activities have removed much of the Mediterranean vegetation on the Balearic Islands, it seems clear that the changes have been brought about, in part, by increasing dryness.

Last-glacial paleoenvironments have been reconstructed from a pollen and charcoal record analyzed in organic sediments and dated between ca. 18,000 and >48,00014C yr B.P. The site is located near the village Catas Altas in the lower highland region of southeastern Brazil. The last-glacial landscape was covered by extensive areas of subtropical grasslands and small areas of gallery forests along the rivers, where tropical semideciduous forests and cerrado ecosystems exist today. The subtropical gallery forests were composed ofAraucariaforest trees such asAraucaria angustifolia, Podocarpus, Drimys, Ilex,andSymplocos.Paleofires were frequent. The record indicates that subtropical grassland vegetation, which today is found in patches on the highlands in southern Brazil (especially in the state of Santa Catarina), expanded from southern Brazil to southeastern Brazil, over a distance of more than 750 km, from latitudes of about 28° S to at least 20° S. The completely different last-glacial environment, in comparison to the present-day environment, reflects a dry and cold climate with strong frosts during the winter months. Temperatures of 5°–7°C below those of the present are inferred for the last glaciation.

Seismic stratigraphy, sedimentary facies, pollen stratigraphy, diatom-inferred salinity, stable isotope (δ18O and δ13C), and chemical composition (Sr/Ca and Mg/Ca) of authigenic carbonates from Moon Lake cores provide a congruent Holocene record of effective moisture for the eastern Northern Great Plains. Between 11,700 and 950014C yr B.P., the climate was cool and moist. A gradual decrease in effective moisture occurred between 9500 and 710014C yr B.P. A change at about 710014C yr B.P. inaugurated the most arid period during the Holocene. Between 7100 and 400014C yr B.P., three arid phases occurred at 6600–620014C yr B.P., 5400–520014C yr B.P., and 4800–460014C yr B.P. Effective moisture generally increased after 400014C yr B.P., but periods of low effective moisture occurred between 2900–280014C yr B.P. and 1200–80014C yr B.P. The data also suggest high climatic variability during the last few centuries. Despite the overall congruence, the biological (diatom), sedimentological, isotopic, and chemical proxies were occassionally out of phase. At these times the evaporative process was not the only control of lake-water chemical and isotopic composition.

An isotopic investigation of upper Pleistocene mammal bones and teeth from Scladina cave (Sclayn, Belgium) demonstrated the very good quality of collagen preservation. A preliminary screening of the samples used the amount of nitrogen in whole bone and dentine in order to estimate the preserved amount of collagen before starting the extraction process. The isotopic abundances of fossil specimens from still-extant species are consistent with their trophic position. Moreover, the15N isotopic abundance is higher in dentine than in bone in bears and hyenas, a phenomenon already observed in modern specimens. These results demonstrate that the isotopic compositions of samples from Scladina cave can be interpreted in ecological terms. Mammoths exhibit a high15N isotopic abundance relative to other herbivores, as was the case in Siberian and Alaskan samples. These results suggest distinctive dietary adaptations in herbivores living in the mammoth steppe. Cave bears are clearly isotopically different from coeval brown bears, suggesting an ecological separation between species, with a pure vegetarian diet for cave bear and an omnivorous diet for brown bear.