Attribution of extreme weather events in Africa: A preliminary exploration of the science and policy implications

At the most recent session of the Conference of the Parties (COP19) in Warsaw (November 2013) the Warsaw international mechanism for loss and damage associated with climate change impacts was established under the United Nations Framework Convention on Climate Change (UNFCCC). The mechanism aims at promoting the implementation of approaches to address loss and damage associated with the adverse effects of climate change. Specifically, it aims to enhance understanding of risk management approaches to address loss and damage. Understanding risks associated with impacts due to highly predictable (slow onset) events like sea-level rise is relatively straightforward whereas assessing the effects of climate change on extreme weather events and their impacts is much more difficult. However, extreme weather events are a significant cause of loss of life and livelihoods, particularly in vulnerable countries and communities in Africa. The emerging science of probabilistic event attribution is relevant as it provides scientific evidence on the contribution of anthropogenic climate change to changes in risk of extreme events. It thus provides the opportunity to explore scientifically-backed assessments of the human influence on such events. However, different ways of framing attribution questions can lead to very different assessments of change in risk. Here we explain the methods of, and implications of different approaches to attributing extreme weather events with a focus on Africa. Crucially, it demonstrates that defining the most appropriate attribution question to ask is not a science decision but needs to be made in dialogue with those stakeholders who will use the answers.

Do location specific forecasts pose a new challenge for communicating uncertainty?

In the last decade, the growth of local, site-specific weather forecasts delivered by mobile phone or website represents arguably the fastest change in forecast consumption since the beginning of Television weather forecasts 60 years ago. In this study, a street-interception survey of 274 members of the public a clear first preference for narrow weather forecasts above traditional broad weather forecasts is shown for the first time, with a clear bias towards this preference for users under 40. The impact of this change on the understanding of forecast probability and intensity information is explored. While the correct interpretation of the statement ‘There is a 30% chance of rain tomorrow’ is still low in the cohort, in common with previous studies, a clear impact of age and educational attainment on understanding is shown, with those under 40 and educated to degree level or above more likely to correctly interpret it. The interpretation of rainfall intensity descriptors (‘Light’, ‘Moderate’, ‘Heavy’) by the cohort is shown to be significantly different to official and expert assessment of the same descriptors and to have large variance amongst the cohort. However, despite these key uncertainties, members of the cohort generally seem to make appropriate decisions about rainfall forecasts. There is some evidence that the decisions made are different depending on the communication format used, and the cohort expressed a clear preference for tabular over graphical weather forecast presentation.

Hellenistic Far East bibliography

A bibliography covering the archaeology of Bactria, Sogdiana, Arachosia and Gandhāra in the period of the Graeco-Bactrian and Indo-Greek kingdoms

The reception of T. S. Bayer’s 'Historia Regni Graecorum Bactriani' (1738)

Theophilus (Gottlieb) Siegfried Bayer (1694-1738) is usually credited as the first person in modern times to address the history of the Greeks in Bactria in a serious way. Bayer’s Historia Regni Graecorum Bactriani, brings together numismatic and historical research. He describes two Graeco-Bactrian coins which he was able to examine first hand, and collects and comments upon the Classical historical sources on the Greek kingdoms of Bactria and India. It was published in St. Petersburg in 1738, where Bayer, a German, held an academic position. In this short article, I am interested in two questions surrounding the Historia Regni Graecorum Bactriani. First (and relatively briefly), how Bayer conducted his research without first hand access to source material and without himself travelling in Bactria – or indeed further east than St. Petersburg. Secondly, the way in which Bayer’s scholarship was received by some of his contemporaries and by later writers, outside the field of Bactrian studies.