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The Pliocene Epoch (∼5.3–2.6 million years ago, Ma) was characterized by a warmer than present climate with smaller Northern Hemisphere ice sheets, and offers an example of a climate system in long‐term equilibrium with current or predicted near‐future atmospheric CO2 concentrations (pCO2). A long‐term trend of ice‐sheet expansion led to more pronounced glacial (cold) stages by the end of the Pliocene (∼2.6 Ma), known as the "intensification of Northern Hemisphere Glaciation" (iNHG). We assessed the spatial and temporal variability of ocean temperatures and ice‐volume indicators through the late Pliocene and early Pleistocene (from 3.3 to 2.4 Ma) to determine the character of this climate transition. We identified asynchronous shifts in long‐term means and the pacing and amplitude of shorter‐term climate variability, between regions and between climate proxies. Early changes in Antarctic glaciation and Southern Hemisphere ocean properties occurred even during the mid‐Piacenzian warm period (∼3.264–3.025 Ma) which has been used as an analog for future warming. Increased climate variability subsequently developed alongside signatures of larger Northern Hemisphere ice sheets (iNHG). Yet, some regions of the ocean felt no impact of iNHG, particularly in lower latitudes. Our analysis has demonstrated the complex, non‐uniform and globally asynchronous nature of climate changes associated with the iNHG. Shifting ocean gateways and ocean circulation changes may have pre‐conditioned the later evolution of ice sheets with falling atmospheric pCO2. Further development of high‐resolution, multi‐proxy reconstructions of climate is required so that the full potential of the rich and detailed geological records can be realized. Plain Language Summary: Warm climates of the geological past provide windows into future environmental responses to elevated atmospheric CO2 concentrations, and past climate transitions identify important or sensitive regions and processes. We assessed the patterns of average ocean temperatures and indicators of ice sheet size over hundreds of thousands of years, and compared to shorter‐term variability (tens of thousands of years) during a recent transition from late Pliocene warmth (when CO2 was similar to present) to the onset of the large and repeated advances of northern hemisphere ice sheets referred to as the "ice ages." We show that different regions of the climate system changed at different times, with some changing before the ice sheets expanded. The development of larger ice sheets in the Northern Hemisphere then impacted ocean temperatures and circulation, but there were many regions where no impacts were felt. Our analysis highlights regional differences in the timing and amplitudes of change within a globally‐significant climate transition as well as in response to the current atmospheric CO2 concentrations in our climate system. Key Points: The "stable" warm late Pliocene ∼3.3–3.1 million years ago was a time of climate transition, especially in the southern hemisphereOcean temperatures and ice sheets evolved asynchronously 3.3–2.4 Ma during the onset and intensification of Northern Hemisphere GlaciationClimate variability evolved in complex, non‐uniform ways, most strongly expressed in northern mid‐latitude sea‐surface temperature records [ABSTRACT FROM AUTHOR]

The geological history of the South Asian monsoon (SAM) before the Pleistocene is not well-constrained, primarily due to a lack of available continuous sediment archives. Previous studies have noted an intensification of SAM precipitation and atmospheric circulation during the middle Miocene (~14 Ma), but no records are available to test how the monsoon changed prior to this. In order to improve our understanding of monsoonal evolution, geochemical and sedimentological data were generated for the Oligocene-early Miocene (30-20 Ma) from Indian National Gas Hydrate Expedition 01 Site NGHP-01- 01A in the eastern Arabian Sea, at 2,674 m water depth. We find the initial glaciation phase (23.7-23.0 Ma) of the Oligocene-Miocene transition (OMT) to be associated with an increase in water column ventilation and water mass mixing, suggesting an increase in winter monsoon type atmospheric circulation, possibly driven by a relative southward shift of the intertropical convergence zone. During the latter part of the OMT, or "deglaciation" phase (23.0-22.7 Ma), a long-term decrease in Mn (suggestive of deoxygenation), increase in Ti/Ca and dissolution of the biogenic carbonate fraction suggest an intensification of a protosummer SAM system, characterized by the formation of an oxygen minimum zone in the eastern Arabian Sea and a relative increase of terrigenous material delivered by runoff to the site. With no evidence at this site for an active SAM prior to the OMT we suggest that changes in orbital parameters, as well as possibly changing Tethyan/Himalayan tectonics, caused this step change in the proto-monsoon system at this intermediate-depth site. [ABSTRACT FROM AUTHOR]

The Late Cretaceous–Early Paleogene is the most recent period in Earth history that experienced sustained global greenhouse warmth on multimillion year timescales. Yet, knowledge of ambient climate conditions and the complex interplay between various forcing mechanisms are still poorly constrained. Here we present a 14.75 million‐year‐long, high‐resolution, orbitally tuned record of paired climate change and carbon‐cycling for this enigmatic period (~67–52 Ma), which we compare to an up‐to‐date compilation of atmospheric pCO2 records. Our climate and carbon‐cycling records, which are the highest resolution stratigraphically complete records to be constructed from a single marine site in the Atlantic Ocean, feature all major transient warming events (termed "hyperthermals") known from this time period. We identify eccentricity as the dominant pacemaker of climate and the carbon cycle throughout the Late Maastrichtian to Early Eocene, through the modulation of precession. On average, changes in the carbon cycle lagged changes in climate by ~23,000 years at the long eccentricity (405,000‐year) band, and by ~3,000–4,500 years at the short eccentricity (100,000‐year) band, suggesting that light carbon was released as a positive feedback to warming induced by orbital forcing. Our new record places all known hyperthermals of the Late Maastrichtian–Early Eocene into temporal context with regards to evolving ambient climate of the time. We constrain potential carbon cycle influences of Large Igneous Province volcanism associated with the Deccan Traps and North Atlantic Igneous Province, as well as the sensitivity of climate and the carbon‐cycle to the 2.4 million‐year‐long eccentricity cycle. Plain Language Summary: The study of globally warm climates and short‐lived warming events in Earth's past can provide unrivaled insights into the challenges that mankind may face over the next few generations. Using samples recovered from an ocean drill core in the deep South Atlantic, we have generated continuous temperature and carbon cycle records from the calcite shells of a single microfossil species, spanning a period of globally warm climate from 67 to 52 million years ago, before the development of permanent large‐scale polar ice sheets. Our record contains a number of rapid warming events, allowing us to determine their origin. We find that changes in the shape of Earth's orbit around the Sun initiated warming at Earth's surface, which was then amplified by the release of greenhouse gases from temperature‐ or climate‐sensitive carbon stores (e.g., peat, permafrost, or methane hydrates). These rapid warming events increased in frequency and magnitude during the warmer climate intervals characterized by significant volcanic activity, suggesting that such carbon stores become more unstable during warmer climates. As our climate warms at unprecedented rates, the release of greenhouse gases from naturally occurring temperature‐ or climate‐sensitive carbon stores could also form an additional and largely unconstrained contribution to future climate change. Key Points: 405‐ and 100‐kyr eccentricity forced the climate and carbon cycle, with carbon cycle perturbations lagging climate during this timeElevated global temperatures and atmospheric pCO2 during LIP volcanism increased climate and carbon cycle sensitivity to orbital forcingThe frequency of hyperthermals suggests that carbon was periodically released from a dynamic reservoir which could be replenished quickly [ABSTRACT FROM AUTHOR]

Historically, community engagement (CE) in research has been implemented in the fields of public health, education and agricultural development. In recent years, international discussions on the ethical and practical goals of CE have been extended to human genomic research and biobanking, particularly in the African context. While there is some consensus on the goals and value of CE generally, questions remain about the effectiveness of CE practices and how to evaluate this. Under the auspices of the Human Heredity and Health in Africa Initiative (H3Africa), the H3Africa CE working group organized a workshop in Stellenbosch, South Africa in March 2016 to explore the extent to which communities should be involved in genomic research and biobanking and to examine various methods of evaluating the effectiveness of CE. In this paper, we present the key themes that emerged fromthe workshop and make a case for the development of a rigorous application, evaluation and learning around approaches for CE that promote a more systematic process of engaging relevant communities. We highlight the key ways in which CE should be embedded into genomic research and biobanking projects. [ABSTRACT FROM AUTHOR]

A report on the Second H3Africa Ethics Consultation Meeting, which was held in Livingstone, Zambia on 11 May 2015. The meeting demonstrated considerable evolution by African Research Ethics Committees on thinking about broad consent as a consent option for genomics research and biobanking. The meeting concluded with a call for broader engagement with policy makers across the continent in order to help these recognise the need for guidance and regulation where these do not exist and to explore harmonisation where appropriate and possible. [ABSTRACT FROM AUTHOR]