211 research outputs found
Defining the hundred year flood: a Bayesian approach for using historic data to reduce uncertainty in flood frequency estimates
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
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 10 an acre for the 2,350 acres burned.
Accounting for Sustainability in Asia: Stock Market Regulation and Reporting in Hong Kong and Singapore
10.1080/00130095.2018.1544461Economic Geography954362-38
The Right Stuff? Informing Adaptation to Climate Change in British Local Government
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
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HESS Opinions: On forecast (in)consistency in a hydro-meteorological chain: curse or blessing?
Flood forecasting increasingly relies on numerical weather prediction forecasts to achieve longer lead times. One of the key difficulties that is emerging in constructing a decision framework for these flood forecasts is what to dowhen consecutive forecasts are so different that they lead to different conclusions regarding the issuing of warnings or triggering other action. In this opinion paper we explore some of the issues surrounding such forecast inconsistency (also known as "Jumpiness", "Turning points", "Continuity" or number of "Swings"). In thsi opinion paper we define forecast inconsistency; discuss the reasons why forecasts might be inconsistent; how we should analyse inconsistency; and what we should do about it; how we should communicate it and whether it is a totally undesirable property. The property of consistency is increasingly emerging as a hot topic in many forecasting environments
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Reducing inconsistencies in point observations of maximum flood inundation level
Flood simulation models and hazard maps are only as good as the underlying data against which they are calibrated and tested. However, extreme flood events are by definition rare, so the observational data of flood inundation extent are limited in both quality and quantity. The relative importance of these observational uncertainties has increased now that computing power and accurate lidar scans make it possible to run high-resolution 2D models to simulate floods in urban areas. However, the value of these simulations is limited by the uncertainty in the true extent of the flood. This paper addresses that challenge by analyzing a point dataset of maximum water extent from a flood event on the River Eden at Carlisle, United Kingdom, in January 2005. The observation dataset is based on a collection of wrack and water marks from two postevent surveys. A smoothing algorithm for identifying, quantifying, and reducing localized inconsistencies in the dataset is proposed and evaluated showing positive results. The proposed smoothing algorithm can be applied in order to improve flood inundation modeling assessment and the determination of risk zones on the floodplain
TB131: Tree Improvement in the Northeast: Interim Summary and Recommendations for Selected Species
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
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Notes from the Deck of the Postmodern Titanic: A Response to David Harvey
Exploiting the archive: and the animals came in two by two, 16mm, CD-ROM and BetaSp
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
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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