RADIOCARBON DATES FROM THE OXFORD AMS SYSTEM: ARCHAEOMETRY DATELIST 2

In an effort to make measurements readily available as soon as possible, dates from the Oxford Radiocarbon Accelerator will now be published regularly in Archaeometry. These datelists will not be a substitute for final publication in Radiocarbon, which is desirable for all dates, but are intended to serve as a formal interim publication of dates, so that they can be cited.     

Climate change and security: examining China's challenges in a warming world

The environment is increasingly affected by global climate change. While the causes of climate change are generated across the globe, the impacts of climate change will be highly variable at the local level. An increased scientific understanding of the potential impacts that climate change may have within China has raised new concern among China's leaders. Given that China's domestic realities inform its international policy choices, understanding how climate change may affect its population and natural resources is critical to global climate stabilization efforts. This article examines how the impacts of climate change on China, and China's response, will drive security challenges domestically, as well as in the greater Asian region and around the world. It shows that the impact of climate change on China will be significant and may have sizable adverse economic implications, particularly on vulnerable east coast economic centers. Water scarcity is a problem that already challenges China's leadership and one that will be exacerbated under projected climate impacts. In addition, the country faces the risk of international retaliation should it fail to undertake serious greenhouse gas mitigation actions. Yet China is not without options, and is already well poised to become a leader in the low-carbon technology revolution.     

Establishing Stage‐Discharge Relationships in Multiple‐Channelled,Ephemeral Rivers: a Case Study of the Diamantina River,Australia

The method for deriving a stage‐discharge relationship has a significant impact on the shape of the river's rating curve. We compare rating curves for a single gauging station on a mutiple‐channelled river in Australia compiled using three different methods – the Urban Runoff and Basin Systems (URBS) rainfall‐runoff model, an empirically‐based velocity‐area method, and the predictive Hydrologic Engineering Centre‐River Analysis System (HEC‐RAS) computer model. The rainfall‐runoff model was found to predict lower discharges for stage heights over 3.5 m than both the empirically‐based velocity‐area method and the HEC‐RAS model. The empirically‐based velocity‐area model predicts similar discharges to the rainfall‐runoff model for stage heights less than 3 m but much higher discharges for larger flood events. The HEC‐RAS model predicts higher discharges than both other rating curves at all stage heights probably due to under‐estimation of the impact of surface roughness on flow velocity. The three models are discussed with particular reference to their use on multiple‐channelled rivers.