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Up-to-date regional and local assessments of changing climate extremes are important to allow countries to make informed decisions on mitigation and adaptation strategies, and to put these changes into a global context. A workshop for countries from the Indo-Pacific region has brought together daily observations from 13 countries for an analysis of climate extremes between 1971 and 2005. This paper makes use of the workshop outcomes and post-workshop analyses to build on previous work in Southeast Asia to update the assessment of changing climate extremes using newly available station data. We utilise a consistent and widely tested methodology to allow a direct comparison of the results with those from other parts of the world. The relationship of inter-annual variability in the climate extremes indices with sea surface temperature (SST) patterns has been investigated with a focus on the influence of the El Niño-Southern Oscillation phenomenon. The results support findings from elsewhere around the globe that warm extremes, particularly at night, are increasing and cold extremes are decreasing. Trends in precipitation extremes are less spatially consistent across the region.  Royal Meteorological Society and Crown

Quero deixar registrado os meus agradecimentos a todas a pessoas e instituições que colaboraram na realização deste trabalho. Se esqueço de citar alguém é porque a memória me traiu, mas sou grato a todos.

Absolute dating methods have been used in chronological studies of geological processes and sedimentary units of Quaternary age in Central Amazonia, Brazil. Although radiocarbon dating has been very useful in archaeological research and soil studies, the temporal interval of this method is inefficient in evaluating the sedimentation aspects and geological events from the beginning of the Quaternary in the Amazon basin. The use of crystal luminescence dating has been one of the most promising tool for determining the absolute dating of Quaternary deposits in the Amazonian region. Optically stimulated luminescence (OSL) dating, following the MAR and SAR protocols, in a tectonic-sedimentary study of Quaternary fluvial deposits in the confluence area of the Negro and Solimões rivers, indicated ages from 1.3 (Holocene) to about 67.4 kyears (Late Pleistocene) for these sediments. Low radioactive isotope concentrations were found about 2ppm for 235 U and 238 U; 5ppm for 232 Th; and the 40 K concentrations were almost zero. A comparison was made between MAR and SAR protocols taking into account the fluvial depositional process.

Aim: To investigate the evolution of the avifauna associated to Amazonian fluvial islands, focusing on the Negro River archipelagos.Locations: Fluvial islands in the Amazon Basin.Methods: One generalist floodplain species (Hypocnemoides melanopogon) and three river island specialists (Myrmotherula assimilis, Myrmoborus lugubris and Thamnophilus nigrocinereus) were studied (Thamnophilidae). We sequenced two mitochondrial genes and genotyped eight microsatellite loci. Phylogenetic relationships among intraspecific lineages and divergence times were estimated using Bayesian Inference.Haplotype networks, AMOVA (analysis of molecular variance) and Mantel tests were used to verify the spatial organization of genetic diversity. Gene flow and population structure were evaluated using a dissimilarity index, Bayesian inference and allele frequencies. Historical demography was inferred through neutrality tests and Extended Bayesian skyline plots (EBSP).Results: River island specialists have evolved distinct lineages in different Amazonian tributaries, but exhibit very weak population structure within the Negro river basin. The generalist floodplain species had no population structure along the Amazon basin or within the Negro river basin. Signals of weak and recent (Pleistocene) population expansion were recovered for all species.Main conclusions: River islands specialists show stronger population structure within Amazonia than floodplain generalists. They show a common spatial and temporal pattern of divergence between populations from the Negro islands and western Amazonia (upper and middle Solimões), which may be related to Amazonian drainage evolution. Island specialists had low genetic diversity within the Negro basin, while the higher and unstructured diversity pattern found in the floodplain generalist species may be a consequence of higher dispersal caused by the seasonal flooding pulse. River islands populations have a recent and dynamic history of contact and isolation, with small historical fluctuations of population sizes, which is in sharp contrast with the patterns found in upland forest birds.

The margin of the Foz do Amazonas Basin saw a shift from predominantly carbonate to siliciclastic sedimentation in the early late Miocene. By this time, the Amazon shelf had also been incised by a canyon that allowed direct influx of sediment to the basin floor, thus confirming that the palaeo‐Amazon fan had already initiated by that time (9.5–8.3 Ma). Above this interval, during a prolonged lowstand, Messinian third‐order sequences are preserved only in the incised‐valley fills of the canyon with no equivalent strata on the shelf. Third‐ and fourth‐order sequences younger than Messinian are preserved on the shelf after sea‐level rise above the shelf by the early Pliocene. Sequences younger than 3.8 Ma often show fourth‐order cyclicity with an average duration of 400 ka (larger scale eccentricity cycles) often preserved in high‐sedimentation‐rate areas of river deltas. Mass wasting and transportation of slope sediments to the basin began to play an important role in sediment dispersal at least as far back as the mid‐Pliocene, after rapid progradation had produced steeper slopes more prone to failure.

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