1,721,122 research outputs found
Water Resources Research in 2013
No full textThe year 2013 marked important changes for Water Resources Research (WRR). On the one hand, some of them can be considered as part of the usual development of the journal that is coevolving with the international hydrological community. On the other hand, some changes that occurred in 2013 marked a major and perhaps irreversible shift for WRR. It is well known that change, in all human expressions and even in Nature, typically induces difficult transition periods. However, change is necessary to adapt to shifting external and internal conditions and its actual impact and implications can be evaluated in the long term only. This editorial presents a summary and a personal assessment of the development of WRR in 2013, including an overview of submission statistics as well as emerging and dominant thematic areas. Reviewing the status of WRR in 2013 is an opportunity to elaborate a perspective on the current patterns in Water Resources Research.
The major changes that WRR experienced in 2013 are summarized by the following events: (1) the production of WRR has been transferred from AGU to Wiley-Blackwell. As a consequence, the web site of WRR has been renewed and the layout for published papers was radically revised. (2) The Editorial Board of WRR underwent the planned transition to a new set of editors that began their term in April 2013. (3) The number of submissions and published papers increased, according to the trend that WRR has experienced in the recent years. These three events are discussed in the following sections of this editorial, which also includes an overview of the emerging research areas and some concluding personal remarks
Modeling and mitigating natural hazards: Stationarity is immortal!
No full textEnvironmental change is a reason of relevant concern as it is occurring at an unprecedented pace and might increase natural hazards. Moreover, it is deemed to imply a reduced representativity of past experience and data on extreme hydroclimatic events. The latter concern has been epitomized by the statement that “stationarity is dead.” Setting up policies for mitigating natural hazards, including those triggered by floods and droughts, is an urgent priority in many countries, which implies practical activities of management, engineering design, and construction. These latter necessarily need to be properly informed, and therefore, the research question on the value of past data is extremely important. We herein argue that there are mechanisms in hydrological systems that are time invariant, which may need to be interpreted through data inference. In particular, hydrological predictions are based on assumptions which should include stationarity. In fact, any hydrological model, including deterministic and nonstationary approaches, is affected by uncertainty and therefore should include a random component that is stationary. Given that an unnecessary resort to nonstationarity may imply a reduction of predictive capabilities, a pragmatic approach, based on the exploitation of past experience and data is a necessary prerequisite for setting up mitigation policies for environmental risk
Reply to comment by Grey Nearing on “A blueprint for process-based modeling of uncertain hydrological systems”
No full textThis article is a reply to Nearing [2014], doi:10.1002/2013WR014812
Characterizing and Modeling Seasonality in Extreme Rainfall
No full textA comprehensive understanding of seasonality in extreme rainfall is essential for climate studies, flood prediction, and various hydrological applications such as scheduling season-specific engineering works, intra-annual management of reservoirs, seasonal flood risk mitigation, and stormwater management. To identify seasonality in extreme rainfall and quantify its impact in a theoretically consistent yet practically appealing manner, we investigate a data set of 27 daily rainfall records spanning at least 150 years. We aim to objectively identify periods within the year with distinct seasonal properties of extreme rainfall by employing the Akaike information criterion. Optimal partitioning of seasons is identified by minimizing the within-season variability of extremes. The statistics of annual and seasonal extremes are evaluated by fitting a generalized extreme value distribution to the annual and seasonal block maxima series. The results indicate that seasonal properties of rainfall extremes mainly affect the average values of seasonal maxima and their variability, while the shape of their probability distribution and its tail do not substantially vary from season to season. Uncertainty in the estimation of the generalized extreme value parameters is quantified by employing three different estimation methods (maximum likelihood, method of moments, and least squares), and the opportunity for joint parameter estimation of seasonal and annual probability distributions of extremes is discussed. The effectiveness of the proposed scheme for seasonal characterization and modeling is highlighted when contrasted to results obtained from the conventional approach of using fixed climatological seasons
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Runoff of small rocky headwater catchments: Field observations and hydrological modeling.
No full textIn dolomitic headwater catchments, intense rainstorms of short duration produce runoff discharges that often trigger debris
flows on the scree slopes at the base of rock cliffs. In order to measure these discharges, we placed a measuring facility at the outlet (elevation 1770 m a.s.l.) of a small,
rocky headwater catchment (area 0.032 km^2, average slope 320 % located in the Venetian Dolomites (North Eastern Italian Alps). The facility consists of an
approximately rectangular basin, ending with a sharp-crested weir. Six runoff events were recorded in the period 2011-2014, providing a unique opportunity for characterizing the
hydrological response of the catchment. The measured hydrographs display impulsive shapes, with an abrupt raise up to the peak, followed by a rapidly decreasing tail, until a
nearly constant plateau is eventually reached. This behavior can be simulated by means of a distributed hydrological model if the excess rainfall is
determined accurately. We show that using the Soil Conservation Service Curve-Number (SCS-CN) method and assuming a constant routing velocity invariably results in an
underestimated peak flow and a delayed peak time. A satisfactory prediction of the impulsive hydrograph shape including peak
value and timing is obtained only by combining the SCS-CN procedure with a simplified version of the Horton equation, and
simulating runoff routing along the channel network through a matched diffusivity kinematic wave model. The robustness of the proposed methodology is tested through a comparison between simulated
and observed timings of runoff or debris flow occurrence in two neighboring alpine basins
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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