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Fire causes dramatic energy and matter exchanges between biosphere and atmosphere on a regional to global scale. Predicting fires, however, is hindered by the complex interplay of fire, climate, and vegetation. Paleo-fire records provide critical information beyond instrumental records that cover only the past few decades and may be used to assess the role of fire in large-scale and long-term environmental changes. Here we present a 22,000-year multiproxy record of fire regime from a sediment core retrieved offshore South Java, Indonesia. We use microcharcoal in combination with two molecular markers of burning, levoglucosan and polycyclic aromatic hydrocarbons, to reconstruct fire occurrence as well as fire intensity in the past. We show that fire occurrence and intensity were high during the Last Glacial Maximum (LGM; around 21,000 years ago) and low during the Heinrich Stadial 1 and the early Holocene. Both fire regime and vegetation in tropical regions with high annual rainfall were primarily controlled by rainfall seasonality. However, fire additionally stabilized the savannah (rainforest)-dominated ecosystem during the LGM (early Holocene) but caused transitions between the two vegetation types during the deglaciation and the late Holocene.

Glacial-interglacial fluctuations in the vegetation of South Africa might elucidate the climate system at the edge of the tropics between the Indian and Atlantic Oceans. However, vegetation records covering a full glacial cycle have only been published from the eastern South Atlantic. We present a pollen record of the marine core MD96-2048 retrieved by the Marion Dufresne from the Indian Ocean similar to 120 km south of the Limpopo River mouth. The sedimentation at the site is slow and continuous. The upper 6 m (spanning the past 342 Ka) have been analysed for pollen and spores at millennial resolution. The terrestrial pollen assemblages indicate that during interglacials, the vegetation of eastern South Africa and southern Mozambique largely consisted of evergreen and deciduous forests. During glacials open mountainous scrubland dominated. Montane forest with Podocarpus extended during humid periods was favoured by strong local insolation. Correlation with the sea surface temperature record of the same core indicates that the extension of mountainous scrubland primarily depends on sea surface temperatures of the Agulhas Current. Our record corroborates terrestrial evidence of the extension of open mountainous scrubland (including fynbos-like species of the high-altitude Grassland biome) for the last glacial as well as for other glacial periods of the past 300 Ka.

The sedimentary sequences of the continental margin off southwest Africa have been shaped by different forces: So, the interaction of climate, oceanic currents and sea level fluctuations left a significant imprint in the sedimentary structures along the continental margin. Additionally, tectonic movements affected the sedimentary sequences. Our aim is to unravel the development and modifications of the depositional system in the Northern Cape Basin, and to deduce global paleoclimatological and paleoceanographic changes from local processes.We present a seismostratigraphic model for the Neogene sedimentary layers in the Northern Cape Basin based on a combination of reflection seismic lines with drill site records of the ODP Leg 175 Site 1082, and assisted by palynological data (Fig.1).A striking observation is the unconformity NCB-B dated at 2.2 Ma. The reflectors above onlap onto this interface, whereas the internal reflectors of the unit below show toplap termination. The outbuilding of the slope in the lower unit indicates a low relative sea level. In contrast the sigmoid reflection configuration in the unit above the unconformity is an indication for a gentle rise of relative sea level which indeed corresponds to a rise in eustatic sealevel. Since we can identify this Late Pliocene unconformity 250 km along the margin of the Northern Cape Basin we infer a large regional change in deposition regime. It coincides with a marked change of pollen assemblages (Fig. 2).The accumulation rate of pollen suddenly drops from 50-60 pol/a/ccm in older layers to 8 pol/a/ccm in average after 2.2 Ma. The marked reduction of pollen input into the ocean is interpreted as the result of a loss of a perennial river discharge. It indicates a change of hinterland climate from humid to drier conditions, which in turn is associated with a shift of the Polar Front Zone of the Southern Ocean in the late Pliocene.Also at 2.2 Ma a distinguished drop in CaCO3 content (Fig. 2) suggests a shift

The sedimentary sequences of the continental margin off southwest Africa have been shaped by different forces: So, the interaction of climate, oceanic currents and sea level fluctuations left a significant imprint in the sedimentary structures along the continental margin. Additionally, tectonic movements affected the sedimentary sequences. Our aim is to unravel the development and modifications of the depositional system in the Northern Cape Basin, and to deduce from local processes to global paleoclimatological and paleoceanographic changes.We present a seismostratigraphic model for the Neogene sedimentary layers in the Northern Cape Basin based on a combination of reflection seismic lines with drill site records of the ODP Leg 175 Site 1082, and assisted by palynological data. A striking observation is an unconformity dated at 2.2 Ma. The reflectors above onlap onto this interface, whereas the internal reflectors of the unit below show toplap termination. The outbuilding of the slope in the lower unit indicates a low relative sea level. In contrast the sigmoid reflection configuration in the unit above the unconformity is an indication for a gentle rise of relative sea level which indeed corresponds to a rise in eustatic sealevel. Since we can identify this Late Pliocene unconformity 250 km along the margin of the Northern Cape Basin we infer a large regional change in deposition regime. It coincides with a marked change of pollen assemblages. The accumulation rate of pollen suddenly drops from 50-60 pol/a/ccm in older layers to 8 pol/a/ccm in average after 2.2 Ma. The marked reduction of pollen input into the ocean is interpreted as the result of a loss of a perennial river discharge. It indicates a change of hinterland climate from humid to drier conditions, which in turn is associated with a shift of the Polar Front Zone of the Southern Ocean in the late Pliocene.