Knowledge of historical fire activity tends to be focused at local to landscape scales with few attempts to examine how local patterns of fire activity scale to global patterns. Generally, fire activity varied globally and continuously since the last glacial maximum (LGM) in response to long-term changes in global climate and shorter-term regional changes in climate, vegetation, and human land use. We have synthesised sedimentary charcoal records of biomass burning since the LGM and present global maps showing changes in fire activity for time slices during the past 21,000 years (as differences in charcoal accumulation values compared to pre-industrial). There is strong broad-scale coherence in fire activity after the LGM, but spatial heterogeneity in the signals increases thereafter. In eastern and western North America and western Europe and southern South America, charcoal records indicate less-than-present fire activity from 21,000 to ~11,000 cal yr BP. In contrast, the tropical latitudes of South America and Africa show greaterthan-present fire activity from ~19,000 to ~17,000 cal yr BP whereas most sites from Indochina and Australia show greater-than-present fire activity from 16,000 to ~13,000 cal yr BP. Many sites indicate greater-than-present or near-present activity during the Holocene with the exception of eastern North America and eastern Asia from 8000 to ~2000 cal yr BP, Indonesia from 11,000 to 4000 cal yr BP, and southern South America from 6000 to 3000 cal yr BP where fire activity was less than present. Regional coherence in the patterns of change in fire activity was evident throughout the postglacial period. These complex patterns can be explained in terms of large-scale climate controls modulated by local changes in vegetation and fuel load.

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Aim To evaluate the biomization technique for reconstructing past vegetation in the Eastern Mediterranean–Black Sea–Caspian‐Corridor using an extensive modern pollen data set and comparing reconstructions to potential vegetation and observed land cover data. Location The region between 28–48°N and 22–62°E. Methods We apply the biomization technique to 1,387 modern pollen samples, representing 1,107 entities, to reconstruct the distribution of 13 broad vegetation categories (biomes). We assess the results using estimates of potential natural vegetation from the European Vegetation Map and the Physico‐Geographic Atlas of the World. We test whether anthropogenic disturbance affects reconstruction quality using land use information from the Global Land Cover data set. Results The biomization scheme successfully predicts the broadscale patterns of vegetation across the region, including changes with elevation. The technique discriminates deserts from shrublands, the prevalence of woodlands in moister lowland sites, and the presence of temperate and mixed forests at higher elevations. Quantitative assessment of the reconstructions is less satisfactory: the biome is predicted correctly at 44% of the sites in Europe and 33% of the sites overall. The low success rate is not a reflection of anthropogenic impacts: only 33% of the samples are correctly assigned after the removal of sites in anthropogenically altered environments. Open vegetation is less successfully predicted (33%) than forest types (73%), reflecting the under‐representation of herbaceous taxa in pollen assemblages and the impact of long‐distance pollen transport into open environments. Samples from small basins (<1 km2) are more likely to be reconstructed accurately, with 58% of the sites in Europe and 66% of all sites correctly predicted, probably because they sample an appropriate pollen source area to reflect regional vegetation patterns in relatively heterogeneous landscapes. While methodological biases exist, the low confidence of the quantitative comparisons should not be over‐emphasized because the target maps themselves are not accurate representations of vegetation patterns in this region. Main Conclusions The biomization scheme yields reasonable reconstructions of the broadscale vegetation patterns in the Eastern Mediterranean–Black Sea–Caspian‐Corridor, particularly if appropriate‐sized sampling sites are used. Our results indicate biomization could be used to reconstruct changing patterns of vegetation in response to past climate changes in this region.

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Pollen records and soil development sequences from the Heraklean Peninsula and the Chyornaya Valley provide information on climatic change and fluctuation of ecological boundaries (mesic forests, steppes and sub-Mediterranean shrublands) in southwestern Crimea during the Holocene. Forests of Quercus, Ulmus, Corylus and Carpinus existed in the Heraklean Peninsula between 12 ka and 11 ka. The subsequent reduction of arboreal pollen and the expansion of Artemisia and Knautia, in conjunction with chernozem soil development, indicate prevailing steppe conditions between 11 ka and 7.5 ka. An increase in arboreal pollen, dominated by sub-Mediterranean and Mediterranean taxa, and the development of brown cinnamonic (calfersic) soil suggest higher temperatures and summer drought between 7.5 ka and 5 ka. An increase in arboreal pollen and the development of a meadow cinnamonic soil suggest an increase in moisture between 5.4 ka and 4.6 ka. A subsequent decrease in AP and the development of calcic horizons in cinnamonic soils indicate that a dry phase occurred between 4.2 ka and 3.5 ka. Woodland expansion occurred again after 3.2 ka, only to be interrupted by the establishment of Greek farms in the fifth century BC. An increase in AP on or after the first century BC was the result of climatic amelioration in conjunction with farm abandonment prompted by political crisis and steppe warrior raids. Although Holocene pollen and soil records from the Ukrainian steppes present climate trends similar to the Heraklean Peninsula, differences in plant taxa and soil response to climatic changes exist due to their different position with respect to marine influences.