211 research outputs found

    Defining the hundred year flood: a Bayesian approach for using historic data to reduce uncertainty in flood frequency estimates

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    This paper describes a Bayesian statistical model for estimating flood frequency by combining uncertain annual maximum (AMAX) data from a river gauge with estimates of flood peak discharge from various historic sources that predate the period of instrument records. Such historic flood records promise to expand the time series data needed for reducing the uncertainty in return period estimates for extreme events, but the heterogeneity and uncertainty of historic records make them difficult to use alongside Flood Estimation Handbook and other standard methods for generating flood frequency curves from gauge data. Using the flow of the River Eden in Carlisle, Cumbria, UK as a case study, this paper develops a Bayesian model for combining historic flood estimates since 1800 with gauge data since 1967 to estimate the probability of low frequency flood events for the area taking account of uncertainty in the discharge estimates. Results show a reduction in 95% confidence intervals of roughly 50% for annual exceedance probabilities of less than 0.0133 (return periods over 75 years) compared to standard flood frequency estimation methods using solely systematic data. Sensitivity analysis shows the model is sensitive to 2 model parameters both of which are concerned with the historic (pre-systematic) period of the time series. This highlights the importance of adequate consideration of historic channel and floodplain changes or possible bias in estimates of historic flood discharges. The next steps required to roll out this Bayesian approach for operational flood frequency estimation at other sites is also discussed

    The Field of Consulting Forester

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    The railroad claim agent finished lighting his cigar and with a dirty look at the young man facing him, said And now young teller what makes you thankful that our number twelve set the woods afire two years ago last August tenth? The young man, shifting weight to the other foot: I have the proof, and after having appraised the damages done by the fire, the owners asked me to come to you and file claim for 23,500orinotherwords,anaverageof23,500 or in other words, an average of 10 an acre for the 2,350 acres burned.

    The Right Stuff? Informing Adaptation to Climate Change in British Local Government

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    Local government has a crucial role to play in climate change adaptation, both delivering adaptation strategies devised from above and coordinating bottom-up action. This paper draws on a unique longitudinal dataset to measure progress in adaptation by local authorities (LAs) in Great Britain, comparing results from a national-scale survey and follow-up interviews conducted in 2003 with a second wave of research completed a decade later. Whereas a decade ago LA staff were unable to find scientific information that they could understand and use, we find that these technical-cognitive barriers to adaptation are no longer a major problem for LA respondents. Thanks to considerable Government investment in research and science brokerage to improve the quality and accessibility of climate information, LAs have developed their adaptive capacity, and their staff are now engaging with the ‘right’ kind of information in assessing climate change risks/opportunities. However, better knowledge has not translated into tangible adaptation actions. LAs face substantial difficulties in implementing adaptation plans. Budget cuts and a lack of political support from central government have sapped institutional capacity and political appetite to address long-term climate vulnerabilities, as LAs in Britain now struggle even to deliver their immediate statutory responsibilities. LA adaptation has progressed farthest where it has been rebranded as resiliency to extreme weather so as to fit with the focus on immediate risks to delivering statutory duties. In the current political environment, adaptation officers need information about the economic costs of weather impacts to LA services if they are to build the business case for adaptation and gain the leverage to secure resources and institutional license to implement tangible action. Unless these institutional barriers are addressed, local government is likely to struggle to adapt to a changing climate

    TB131: Tree Improvement in the Northeast: Interim Summary and Recommendations for Selected Species

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    This publication of the regional research project NE-27, Genetics and Improvement of Northeastern Trees, is intended to provide an overview of current knowledge regarding genetic variation and tree improvement practices for eleven common tree species in the Northeast. The authors have attempted to summarize the information that will be most useful to forest managers, administrators, and field foresters in this region. Our intent is to be informative, not exhaustive.https://digitalcommons.library.umaine.edu/aes_techbulletin/1067/thumbnail.jp

    Exploiting the archive: and the animals came in two by two, 16mm, CD-ROM and BetaSp

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    This a post-print, author-produced version of an article accepted for publication in Area. Copyright © 1999 Wiley Blackwell. The definitive version is available at www3.interscience.wiley.comUsing an account of the construction and subsequent exploitation of the film archive at the BBC's Natural History Unit, this paper explores the ways in which animals are embedded in the different cultures of care, control and commodification in the zoo and the wildlife film-making unit. Network analysis is used to account for the similarities and tensions between these forms of animal exhibition, as revealed in the electronic zoo at Wildscreen World

    Membership nominations in international scientific assessments

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    International scientific assessments are transnational knowledge-based expert networks with a mandate to advise policymakers. A well-known example is the Millennium Ecosystem Assessment (MA), which synthesized research on ecosystem services between 2001 and 2005, utilizing the knowledge of 1,360 expert members. Little, however, is known about the membership composition and the driving forces behind membership nominations in the MA and similar organizations. Here we introduce a survey data set on recruitment in the MA and analyse nomination patterns among experts as a complex network. The results indicate that membership recruitment was governed by prior contacts in other transnational elite organizations and a range of other factors related to personal affinity. Network analysis demonstrates how some core individuals were particularly influential in shaping the overall membership composition of the group. These findings add to recently noted concerns about the lack of diversity of views represented in international scientific assessments
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