An improved concept of the best analogs method is used to reconstruct the climate of the last glacial maximum from pollen data in Europe. In order to deal with the lack of perfect analogs of fossil assemblages and therefore to obtain a more accurate climate reconstruction, we used a combination of pollen types grouped according to plant phenology and present climate constraints rather than pollen percentages for each individual taxon. The distribution of pollen taxa into plant functional types (PFTs) is aimed to reflect the vegetation in terms of biomes which have a wider distribution than a species. The climatic variables are then calibrated on these PFTs using an artificial neural network technique. The use of PFTs allowed us to deal with situations where pollen assemblages have only partial modern analogs. The method is applied to the glacial steppic vegetation in Europe, using 15 pollen records. North of the Pyrenees–Alps line, the reconstructed temperatures were lower than today: −30 ± 10°C for the temperature of the coldest month ( Tc) and −12 ± 3°C for the annual mean ( Tann). South of that line, Tc and Tann anomalies were respectively, −15 ± 5°C and −10 ± 5°C. The available moisture index and annual precipitation were also lower than present: −60 ± 20% north of Mediterranean Sea, (−800 ± 100 mm for precipitation). In Italy and Greece, the available moisture was 20% lower, with a precipitation anomaly of ca. −600 ± 200 mm. Southward, the moisture index was close to that at present (±20%), and precipitation was lower (−300 ± 300 mm).

This study presents results fromii a multi-proxy anialysis of cores taken in a crater-lake sequence fromll Eski Acigol in centr-al Turkey which cover the period fromii pre-c. 1600X) cal. yr BP to the present. The sediments comiiprise an upper unit of enerally non-laminated, banded to massive silts and peats of mid-to late-Holocene age, oveilying a laminated tinit of late-Pleistocene to early/miid-Holocenie age. The lamiinlae, comprising mainily aragonite. amorphous silica (diatom trustules) and organic mattei were formed in a relatively deep, dilute. meromiiictic lake. Pollen data indicate an abrupt replacement of Ar;eyisi'io-chenopod steppe by grass-oakterebinth parkland during the period of laminae deposition, imiar-king the start of the Holocenie. A gradual Li i E ;i E; increase in tree pollen during the early Holocene came to a i n end c. 6500 cal. yr BP (U-series and adjusted 4C timescale), when mesic deciduotLs taxa declined at the same timiie as lake levels fell. Human impact on regional vegetation is infened from a sharp decline in oak arotind 4500-.4(X0)0 cal. yr BP. Diatom, isotopic anid mineralogical data indicate that during the second half of the Holocene the lake became relatively shallow and A oscillated between fresh and brackish/evaporated water conditions. The contrast between wetter early-and drier HOLOCENE late-Holocene climatic conditions is matched bv other eastern anid central Mediterranean proxy climate data. SPECIAL ISSUEWhile the Eski Acigol seqtLience resembles Holocene hydroclimatic changes in the Saharo-Arabian zone and was also apparenitly linlked to orbital forcing, it is unlikely to have had the samlle direct cause, i.e., an expansion and subsequent retreat of monsoon rainfall.

Pollen data from 18,000 14 C yr bp were compiled in order to reconstruct biome distributions at the last glacial maximum in southern Europe and Africa. Biome reconstructions were made using the objective biomization method applied to pollen counts using a complete list of dryland taxa wherever possible. Consistent and major differences from present-day biomes are shown.Forest and xerophytic woods/scrub were replaced by steppe, both in the Mediterranean region and in southern Africa, except in south-western Cape Province where fynbos (xerophytic scrub) persisted.Sites in the tropical highlands, characterized today by evergreen forest, were dominated by steppe and/or xerophytic vegetation (cf. today's Ericaceous belt and Afroalpine grassland) at the last glacial maximum.Available data from the tropical lowlands are sparse but suggest that the modern tropical rain forest was largely replaced by tropical seasonal forest while the modern seasonal or dry forests were encroached on by savanna or steppe. Montane forest elements descended to lower elevations than today.

Palynological investigations were carried out in the coastal lowland of northwestern Crete, in the area of Lake Kournas. Results comprise the longest continuous vegetation record (9000 radiocarbon years) for Crete. From about 8500 to 7500 BP, open deciduous-oak forest occurred and appears to reflect the driest conditions of the Holocene. After 7500 BP, tree-pollen numbers increase. Some of these tree species are thought to be autochthonous, but for at least six species this is doubted and the presence of their pollen is ascribed to long-distance transport. Up to 6000 BP, the local vegetation included deciduous and evergreen oaks, Pistacia, Phillyrea and a variety of herbs. Only after 7000 BP, some species, e.g., Mercurialis annua, Cynocrambe and spores of Pteridium, might indicate the effects of Neolithic habitation. Towards 6000 BP, plane tree and Styrax (storax) appear; from about 6000 BP, olive is present and human activity becomes more evident. Slowly, pollen types indicative of the exploitation of present-day Mediterranean vegetation, e.g., Poterium and Ericaceae, appear and the presence of the alga Gloeotrichia indicates a rise in phosphate. A striking aspect of the sediment core nearest to the sea is a pumice layer originating from the Theran (Santorini) eruption. From the manner of its deposition it is concluded that no tsunami met the Cretan beach. Influence of the eruption from Thera on the vegetation is hardly visible. Decrease of economically important cultivated plants, e.g., olive, already took place decades, up to about a century, before the volcanic eruption. Around the time of the eruption, the values of some pollen types hardly changed, others increased and another group decreased. This pollen behaviour appears to be explained rather by socio-economic changes, such as withdrawing of the inhabitants to the interior for reasons other than volcanic effects. It is concluded from the pollen cores that no major climatic changes affected northwestern Crete during the Holocene but the first two millennia of the Holocene tended to be drier than the following period when there was an increase in moisture-demanding trees. It is difficult to assign changes in the Cretan vegetation to climatic effects in a period when human impact was gathering strength.

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