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The Chew Bahir Drilling Project (CBDP) aims to test hypothesized linkages between climate and human evolution, dispersal and technological innovation by the acquisition and analysis of long (~280 m) sediment cores that have recorded environmental change in the Chew Bahir basin, southern Ethiopia. In this time-series analysis project, we consider the Chew Bahir palaeolake to be a dynamical system consisting of interactions between its different components, such as the waterbody, the sediment beneath lake, and the organisms living within and around the lake, and humans within the lake catchment. Recurrence is a common feature of such dynamical systems, with recurring patterns in the state of the system reflecting typical influences. Identifying and defining these influences contributes significantly to our understanding of the dynamics of the system.We use methods of linear and nonlinear time series analysis, such as change point detection, semblance analysis and recurrence plots, to identify and classify recurring types of variability and transitions on the time scales of human life spans. For example, we investigate the rapidness of transitions, possible precursor events, and tipping points in our palaeoenvironmental data and discuss their possible impact on the living conditions of humans in the region. First results of the analysis show that we indeed find, as an example, recurring threshold-type transitions, when the Chew Bahir system switched from one stable mode to another, such as from stable wet to dry conditions. Such a rapid change of climate in response to a relatively modest change in forcing appears to be typical of tipping points in complex systems such as the Chew Bahir. If this is the case then the 14 dry events idenfified at the end of the African Humid Period (15–5 kyr BP) could represent precursors of an imminent tipping point that, if properly interpreted, would allow predictions to be made of future climate change in the Chew Bahir basin. [ABSTRACT FROM AUTHOR]

The sediments of the Chew Bahir playa lake in southern Ethiopia were cored down to 280 m depth in the context of HSPDP (Hominin Sites and Paleolakes Drilling Project) and CRC (Collaborative Research Center) 806 "Our way to Europe" projects. The main aim is to reconstruct the paleoenvironmental conditions during the development of anatomically modern humans (AMH) and to test hypotheses about human evolution, dispersal and technological innovation. Based on several dating methods (14C, Ar/Ar, optical stimulated luminescence, chemical fingerprints of tephras) the composite core is shown to cover the last ~600 ka and therefore brackets the time period of important steps in cultural evolution, from Late Acheulean to Middle/Late Stone Age technologies, the origin of AMH, as well as the most recent "Out of Africa" human dispersal events. The multiproxy record of the composite core (e.g., chemical and physical sediment properties, stable C, O and Sr isotope ratios of carbonates, microfossil assemblages and biomarkers) indicates long- and short-time hydroclimatic changes mainly driven by orbital controlled insolation (mostly the Earth's precession ~15-25 ka, but also eccentricity ~90-120 ka). We compare our Chew Bahir data with results from other long marine and terrestrial paleoclimatic records. Here we focus on particularly strong wet and dry fluctuations at Chew Bahir during the last 200 ka to test established hypotheses for human dispersal and technological innovation. The record indicates that at least some of the human dispersal waves have taken place during wetter environmental conditions offering green corridors in East Africa, one of the source regions of our ancestors. [ABSTRACT FROM AUTHOR]

Cores from terrestrial archives, such as the lacustrine sediments from the Chew Bahir basin in southern Ethiopia, which cover the last ~600 ka, often reflect both local, regional and global climate influences. In our analysis we were able to identify several time windows in which the Chew Bahir climate is in resonance with regional and global climate change.As a contribution to understanding and differentiating these connections recorded in the Chew Bahir sediments, we have correlated the 2nd principal component of the MSCL based color reflectance values representing wet conditions in the Chew Bahir basin, with the wetness index from ocean core ODP 967 from the eastern Mediterranean Sea. The correlation between these two time series was calculated using the Spearman correlation coefficient in a sliding window. Episodes with high correlation between the two records of wetness could indicate a strong link between both regions, possibly through an increased outflow of the river Nile into the eastern Mediterranean Sea due to higher precipitation values on the Ethiopian plateau.Our preliminary results show that when correlating the two records, two distinct temporal units can be distinguished. Between ~570 ka and ~350 ka the correlation is dominated by cycles that correspond with orbital precession whereas the second unit (after 350 ka) reveals a strong influence of atmospheric CO2. This observation suggests that both orbital precession and atmospheric CO2. may cause a synchronization of different regions in the African climate system, possibly depending on boundary conditions which are still to be identified.As a next step we'll investigate the nonlinear relationships between the two records by focusing on the transition between the two main observed phases. The transition around ~350 kyrs however, is not only highly interesting from a climatic perspective, but it is also a noteworthy period for human cultural evolution as a transition from Acheulean to Middle Stone Age (MSA) technologies takes place at this time. So far our results outline that during this climatically and evolutionary relevant episode a relatively stable, long-lasting, pan-African wet phase may have existed, with possible green corridors connecting the habitats of hominins, and ample resources supporting large population sizes. [ABSTRACT FROM AUTHOR]

Since 2015, a multi-hazard partnership consisting of 4 UK Government science agencies and public sector organisations (Animal and Plant Health Agency, Public Health England, Met Office, British Geological Survey) has produced a weekly international overview of natural hazards for UK government departments. Aligning with the Sendai Framework, this novel, collaborative approach joins horizon-scanning scientists in order to anticipate and assess potential emerging international threats and their implications. The overall aim is to improve situational awareness of decision makers across government, allowing the UK government to be more anticipatory in its response to natural hazards and thus to reduce the impact(s) of future disasters on government resources and interests overseas. The International Forward Look (IFL) provides a weekly multi-hazard assessment of hydrometeorological, volcanic, animal, and human health events globally, with an emphasis on new, emerging or deteriorating situations. It predominately reports on current events and their potential evolution, as well as providing meteorological forecasts over the next 7 days. Each contributor scans and evaluates information from a wide range of UK and international sources, including authoritative information from mandated national, regional and global centres, and uses expert scientific knowledge to identify and assess events of interest/concern. The process has been designed to identify events, flag when they are worsening, identify inconsistencies in the evidence, determine where the impact of the hazard could be greatest, and identify potential cascading and interacting events (for instance where the meteorological forecast could interact with a health or volcanic event). Using a novel matrix, individual events are assigned a colour coded rating ranging from grey, through yellow, orange and red to communicate actual or potential increasing likelihood and/or impact. The final output is organised by region and includes two world maps, one highlighting noteworthy human, animal and meteorological events and the other details currently reported volcanoes. The individual entries include a brief summary of the hazard as well as an implications box for the science agencies to provide a more detailed analysis of the situation. The maps contain no political boundaries as the events of concern are observed from a regional perspective, but underlying information is given at a country level.Since its conception, the IFL has provided the UK government with situational awareness and informed response and resource allocation. Though challenges remain, such as the range of recipients and their knowledge and needs, the product is undergoing continual development through stakeholder consultation, with the aim of developing an open-access web-based platform. The value of the IFL is not just the end product and the regional non-political nature of the output, but also the building of organisational and individual relationships that provide a catalyst for innovation and more successful ways to assess risk from multiple natural hazards. [ABSTRACT FROM AUTHOR]