bluuebunny/crossref_metadata_2025 huggingface dataset:
MAPPING OIL SPILL THICKNESS WITH A PORTABLE MULTISPECTRAL AERIAL IMAGER
Authors: Svejkovsky Jan , Muskat Judd , Mullin Joseph
Published: January 2013

Rapid determination of oil thickness patterns within a spill at sea is vital for efficient planning and management of spill response activities. Presently such determinations are made almost solely by airborne visual surveys which require specially trained observers and are prone to errors due to variations in illumination, water color, and other environmental conditions. Our goal is to eliminate the subjectivity of visual assessment techniques by developing a computerized portable imaging system that could provide detailed maps of oil-on-water thickness distributions in near-realtime. We have developed oil thickness determination algorithms that utilize multispectral images from a 4-channel sensor providing oil reflectance data in the UV and three channels between 500 and 700nm. A neural network-based algorithm first isolates all oil-on-water areas from oil-free water, sunglint and other potential artifacts. A fuzzy ratio classification algorithm then maps the oil-contaminated areas for thickness classes. The reflectance ratio-based algorithms were tested with several types of crude and fuel oils at MMS’ Ohmsett facility as well as over natural oil seepage areas in the Santa Barbara Channel, California. The methodology yielded accurate thickness estimates over oil films ranging from sheens to 0.2–0.3mm thick. Although the location of thicker films can be accurately mapped, their absolute thickness cannot be established using the UV-visible wavelength range. The addition of an infrared channel may expand the system'S thickness measurement range and is presently being investigated. The imager also allows the identification of emulsified vs. unemulsified oil, thus providing additional information to help guide efficient spill response. Real-time image processing capabilities are presently being developed to allow the system to disseminate a GIS-compatible map immediately after image data acquisition.
T/B MORRIS J. BERMAN OIL SPILL: RESTORATION PROJECTS OVERVIEW
Authors: Iliff John
Published: January 2013

The January 7, 1994, barge Morris J. Berman grounding and oil spill off Punta Escambrín, near San Juan, Puerto Rico, resulted in injury to natural resources along the shoreline and impaired their use for an extended time. Three major injury categories were pursued by the Trustees and the restoration projects for these injuries are presented in this paper. Including interest, approximately $10M in settlement funds are being used to fund 6 restoration projects. About $6 million of the settlement funds is being used for three projects to restore eolianite reef habitat, a type of fossilized sand dune, and other reef resources injured by the barge grounding and subsequent spill. One project, called the Condado Coral Trail project, will install artificial reef modules in the Condado Lagoon, approximately 1 mile southeast of the barge grounding site. Also in the Condado Lagoon, a 32-acre dredge hole will be brought back to historic elevations through beneficial use of dredged marine sediments. The third reef project entails acquisition of shoreline and coastal property which is intended to provide reef resource services comparable to those lost as a result of the oil spill and grounding. This parcel provides habitat for over 40 rare species of plants and animals including a major nesting beach for the endangered Leatherback Sea Turtle. The acquisition project also serves as the sole compensatory restoration project for lost recreational beach use. The parcel is being designated as a Puerto Rico Natural Reserve thereby allowing the public to use the land, including its unspoiled beaches, for recreational purposes. Finally, three restoration projects are being implemented to compensate for the lost historic visitor use services at the San Juan National Historic Site. More than 123,000 visitors to the El Morro and San Cristobal forts were affected by the spill for approximately six weeks. The first of the three projects includes Improving and Extending the Coastal Promenade, a walkway at the base of El Morro. The second is restoration of El Morro Water Battery and the third is cleaning and stabilizing certain exterior walls of the El Morro Fort.
ADVANCED DETECTION TECHNOLOGY FOR EARLY WARNING - THE KEY TO OIL SPILL PREVENTION
Authors: Chase Chris R. , Roberts Leonard G.
Published: January 2013

This paper discusses the development of an oil spill detection and alarm system that provides industry with a reliable, cost-saving mechanism for containing and/or preventing accidental discharges of hydrocarbon-based pollutants.

By utilizing an automated spill detection system, hydrocarbon releases are detected in real-time (analogous to a ‘smoke alarm’ for oil spills). Early warning and automated response capabilities allows early containment of oil pollution, thereby reducing the volume spilled and minimizing damage to the environment, wildlife, public waterways and/or commercial assets. This technology provides a new weapon in the pollution prevention arsenal, offering Health Safety & Environment (HSE) personnel a critical compliance tool in accordance with National Pollution Discharge Elimination System (NPDES), US EPA Spill Prevention Control & Countermeasure (SPCC), and other regulations stipulating spill prevention, planning and response.

This paper details: 1) Development of a reliable, economical, optical, non contact, UV/fluorometry-type, hydrocarbon pollution detection sensor system 2) Performance results drawn from an array of performance tests and real-world deployments, 3) A variety of existing applications and deployment opportunities for which this new technology offers a reliable solution and easy-to-use tool for both regulatory compliance and realization of cost benefits associated with minimizing spill risk(s).

Design features have evolved to reflect feedback from existing industrial users, as well as input from environmental consultants and regulatory agencies. These key system attributes include: 1) Near-zero maintenance, 2) Micron- level sensitivity for a comprehensive range of oils (from crude-oil to jet-A), and 3) Sensor/system flexibility and adaptability for varied application requirements and a wide range of installation settings (i.e. freshwater, marine, industrial, harbor, offshore, etc.).

Finally this paper describes how any entity that produces, stores, uses, or transports hydrocarbons, can best employ the detection sensor/alarm to realize cost-benefits, strengthen compliance, and eliminate the expense, environmental damage, and bad publicity inherent with any oil spill.
MAPPING DECISIONS TO IMPROVE CRISIS RESPONSE
Authors: Healy William
Published: January 2013

Judgment and decision making are key components of every response and most current contingency plans fail to acknowledge this fully. Decision Mapping is a concept that provides planners with the tools to identify and analyze key decisions that may present themselves during the event timeline, and it prepares leaders to make quick and informed decisions. It provides an organized method to identify stakeholders, information needs, authorities, and consideration thresholds in a prioritized structure to give leaders the right perspective for balancing competing needs. It is a new way to approach contingency planning that goes beyond the listing of resources and views a response as a dynamic event with many uncertain components.
THE ROLE OF PRE-IMPACT SITE ASSESSMENT IN EMERGENCY OIL SPILL RESPONSE PLANNING
Authors: Tan S H , Lerdphomsuttirat N. , Tisavipaksakul A.
Published: January 2013

An oil spill in marine waters can have serious consequences, particularly in the tropical regions, where sensitive resources are abundant and accessibility is poor. The impacts are more significant if the oil reaches the coast and contaminates the shoreline. An oil spill contingency plan (OSCP), which prescribes the actions to be performed under emergency conditions, can greatly reduce the damage to the environment and the disruption in human economic activities.

However, due to the lack of resources, countries in Asia do not always have developed and up to date OSCPs. This paper proposes the use of pre-impact site assessment (PISA) as a strategy to overcome some of the problems arising from such a situation.

Combined with a stochastic and trajectory modeling which are used to predict the locations that are likely to be oiled, the pre-impact site assessment allows the collection of essential information, such as shoreline profile, site accessibility and sensitive resources, within a short period of time to aid the decision making for response planning. This rationale approach can be very useful during salvage operations when there is a risk of having the casualty spilling more oil, or for sunken ships with oil onboard. Oil Spill Response and East Asia Response Limited (OSRL/EARL) has been engaged to conduct PISA in a few incidents of the above condition. These incidents showed that a very quick action was required in order to greatly influence the outcome of the response.

The authors will share the operational experience and the lessons learnt from the few recent case studies mentioned above to demonstrate the significance of this methodology for emergency oil spill response planning.
PUBLIC PARTICIPATION IN U.S. OIL POLLUTION PLANNING AND PREPAREDNESS POLICY
Authors: Yoshioka Gary , Reber Julie , Thompson Ryan , Tilghman Joan
Published: January 2013

Regulatory agencies in the United States represent the Executive Branch of the Federal Government in implementing and enforcing rules, and these agencies are required to follow certain procedures when writing those rules. At a minimum, the agency must publish a notice explaining the proposed rule, request comments, and state the basis and purpose of the final action. This paper provides examples of instances where an agency has revised the rule as a result of comments received or has otherwise been responsive to the commenter'S argument. For example, with regard to oil pollution planning and preparedness policy, commenters on the U.S. Environmental Protection Agency'S proposed revisions to the Spill Prevention Control and Countermeasure (SPCC) plan rule raised the idea of a minimum container size for applicability of the SPCC rule and EPA included such a minimum for the first time in the final rule, thus reducing the burden of the rule for many facilities. Federal agencies are required to request public comments on the issues presented in their proposed rules to enable the agencies to evaluate the new or revised provisions. With agencies now accepting electronic comments through web sites, regulated parties can easily participate in this process. As this paper shows, many agencies that regulate oil pollution planning and preparedness are very responsive to suggestions, and members of the regulated community have an opportunity to influence public policy decisions in this area.
DEVELOPING GUIDELINES FOR JOINT TRANS-BOUNDARY RESOURCE AGENCY INPUT TO DISPERSANT USE, IN-SITUBURNING, AND PLACES OF REFUGE DECISION-MAKING: THE CANADA/UNITED States Dixon Entrance Example
Authors: Bergmann Pamela , Ross Paul
Published: January 2013

Papers presented at the 2001 and 2005 International Oil Spill Conferences (IOSCs) discussed the development of the first-of-its-kind trans-boundary wildlife response guidelines, which were completed for the area known as Dixon Entrance between British Columbia (BC) in Canada and Alaska in the United States (U.S.). This work was conducted within the framework of Canadian Coast Guard (CCG) and United States Coast Guard (USCG) joint contingency planning as outlined in the Annex 5 Canada-United States Dixon Entrance-Geographical Annex to the Canada-United States Joint Marine Pollution Contingency Plan (Canada-U.S. Joint Marine Pollution Contingency Plan CANUSDIX Annex). Along with other topics, the 2005 IOSC paper described a number of unanticipated benefits resulting from the development of the guidelines. This included establishing stakeholder partnerships which facilitated additional joint trans-boundary pre-incident planning.

Following the completion of the Canada-U.S. Dixon Entrance (CANUSDIX) wildlife response guidelines in September 2003, attention was turned to examining trans-boundary decision-making associated with dispersant use, in-situ burning, and places of refuge identification. Subsequently, a joint CANUSDIX Resource Agency Working Group was established to address resource-related topics for activities supporting dispersant use, in-situ burning, and places of refuge decision-making in the Dixon Entrance trans-boundary area. Over the next 2.5 years, working group members prepared draft guidelines for resource agency input to those response activities. In March 2006, the Canadian and U.S. Federal, Canadian Provincial, and State of Alaska resource agencies with jurisdiction in the Dixon Entrance area, finalized the CANUSDIX Guidelines for Resource Agency Input to Dispersant Use, In-Situ Burning, and Places of Refuge Decision-Making (CANUSDIX Resource Agency Guidelines) and submitted the document to the CCG and USCG for inclusion in the Canada-U.S. Joint Marine Pollution Contingency Plan CANUSDIX Annex.

This paper provides an overview of the development of the CANUSDIX Resource Agency Guidelines; a description of the information included in the guidelines; and how the guidelines fit within the CCG and USCG incident management structures. Together, this information will allow other parties in trans-boundary areas around the world to use the CANUSDIX Resource Agency Guidelines, and the process undertaken to develop the document, as a model for conducting similar pre-incident planning.
RESPONDING TO SPILLS IN AN ARCTIC OIL FIELD – LESSONS LEARNED
Authors: Majors Lee , McAdams Fred
Published: January 2013

Alaska Clean Seas (ACS) is the Oil Spill Recovery Organization (OSRO) for the North Slope of Alaska. ACS responds to all spill events for member companies operating on the North Slope. In 2006 ACS responded to over 350 reportable spill events.

These spills consist of materials utilized in oil field production activities and include crude oil, produced water, drag reducing agents, freeze protection material, and even sewage The spills occur on frozen tundra in and under snow and ice, and in summer conditions.

This paper outlines some of the spills in past years, the conditions encountered, tactics utilized, and lessons learned.
BEHAVIOR-BASED SAFETY PROCESSES IN ARCTIC OIL SPILL RESPONSE
Authors: Hall Christopher J. , Henry Walter J.
Published: January 2013

The Alaska North Slope region is a challenging operating environment. During spill response operations, worksite hazards are magnified and ensuring safety of response personnel becomes more difficult. In the Incident Management Team, the Safety Officer develops a Site Safety Plan to identify hazards and establish guidelines for safe operations. This information is typically communicated to the field workers when they check-in at the Staging Area or other assigned location. The Site Safety Plan alone, however, fails to address specific behaviors of the personnel that lead to unsafe activities. Behavior-Based Safety Processes fill in this missing piece.

The PIRATE Process is an example of behavior-based safety at work. PIRATE - Personal Involvement Reduces Accidents to Everyone - is a fundamental part of the safety culture in the Greater Prudhoe Bay operating area. The March 2006 Gathering Center 2 (GC-2) Transit Line oil spill response presented significant challenges to all involved: extreme weather conditions, congested work areas, spilled oil on frozen lake and tundra environments, and complex field operations competing for personnel and resources. Daily involvement with PIRATE (and similar North Slope Behavior-Based Safety Processes) has made the workforce acutely aware of each individuar'S role in workplace safety, enhancing the overall safety performance of the organization.

This poster shows some of the difficulties of a complex arctic oil spill response, and the application of Behavior-Based Safety Processes to enable safe and efficient operations in the face of these challenges.
EVALUATION OF DETERGENCY, INTERFACIAL TENSION AND CONTACT ANGLE FOR FIVE SURFACE WASHING AGENTS
Authors: Koran Karen M. , Venosa Albert D. , Luedeker Christopher
Published: January 2013

The U. S. Environmental Protection Agency (EPA) has developed a laboratory testing protocol to evaluate the effectiveness of surface washing agents (SWAs) to remove crude oil from a solid substrate. Variables were tested to determine their effect on SWA performance. The protocol was most sensitive to SWA:oil ratio (SOR) and rotational speed of mixing; it was not greatly affected by contact time, mixing time, or SWA concentration when total applied mass is constant. Interfacial tension and contact angle were measured for Prudhoe Bay Crude oil in the presence of six SWAs. SWAs were ranked based on 1) efficiency under the developed protocol, 2) ability to reduce interfacial tension and 3) ability to increase oil-substrate contact angle. In order for oil displacement to be thermodynamically favored, an SWA must have a lower interfacial tension with the substrate than does the oil. Using Young'S equation, the difference between the two solid-liquid interfacial tensions was calculated from the three phase contact angle and the interfacial tension between the two liquids. SWAs were ranked based on each of these criteria, and data were correlated with effectiveness under the protocol.
COLD WATER DISPERSANT EFFECTIVENESS EXPERIMENTS CONDUCTED AT OHMSETT WITH ALASKAN CRUDE OILS USING COREXIT 9500 AND 9527 DISPERSANTS
Authors: Mullin Joseph , Belore Randy , Trudel Ken
Published: January 2013

One untested hypothesis in oil spill response is that “chemical dispersants do not work effectively in cold water”. This is due to the general misconception that cold water inhibits dispersant effectiveness (DE) and the lack of experimental data to indicate otherwise. To address this issue, the U.S. Minerals Management Service (MMS) funded and conducted two series of dispersant experiments in very cold water at Ohmsett – The National Oil Spill Response Test facility, located in Leonardo, New Jersey from February-March 2006 and January-March 2007. Four Alaskan crude oils Alaska North Slope (ANS), Endicott, Northstar and Pt. McIntyre and two dispersants Corexit 9500 and Corexit 952 7 were used in the test series. The crude oils were tested fresh, weathered by removal of light ends using air sparging and weathered by placing the oils in the tank in both breaking wave conditions and non-breaking wave conditions. Results from the 2006 and 2007 Ohmsett test series demonstrated that both Corexit 9500 and Corexit 9527 dispersants were more than 90% effective in dispersing the fresh and weathered crude oils tested. This verified the results from laboratory and small-scale experiments. MMS believes that results from these test series will assist government regulators and responders in making science based decisions on the use of dispersants as a response tool for oil spills in the Arctic. The results from the 2006 and 2007 Ohmsett dispersant effectiveness test series dispel the thought that chemical dispersants cannot be effective in cold water.
DO BASINS AND BEAKERS NEGATIVELY BIAS DISPERSANT-EFFECTIVENESS TESTS?
Authors: Nedwed Tim , Coolbaugh Tom
Published: January 2013

Beaker and basin dispersant-effectiveness tests are used to help determine if application of dispersants in a real oil-spill incident is worthwhile. This paper provides evidence indicating that these tests negatively bias expected dispersion at sea because beakers and basins do not allow the spreading of oil slicks that occurs after application of dispersant in the unbounded open ocean. One reason is that closed system walls and/or oil-slick containment methods impose physical boundaries that restrict oil spreading.

In addition to these physical constraints, surfactant films developed after applying dispersant form on the water surface surrounding an oil slick and act as chemical herders to keep slicks thick. This occurs in the field during a real incident and in beaker and basin dispersant-effectiveness tests. Surfactant films on the water surface, however, are fragile and can't persist in the open ocean but can persist throughout the short duration of standard dispersant-effectiveness tests.

This paper provides a background discussion of how surfactant films contaminate the water surface on the perimeter of oil slicks to restrict spreading in both open and closed systems and evidence that these fragile films don't persist in the open ocean. The discussion is followed by a description of lab tests that showed even minimal water-surface contamination from the surfactants in a widely available dispersant significantly restricted spreading to keep slicks thick.

Thick oil slicks, by their nature, will obviously require more turbulence to disperse than a thin film of the same oil. Thus, it is believed that the restricted slick spreading inherent in dispersant-effectiveness tests completed in basins and beakers results in significantly lower performance than would be expected at sea not only for heavier oils but for all oils in tests simulating low-energy conditions.
THE MODELING OF SPILLS RESULTING FROM THE CATASTROPHIC FAILURE OF ABOVE GROUND STORAGE TANKS AND THE DEVELOPMENT OF MITIGATION
Authors: Atherton W. , Ash J. W. , Alkhaddar R. M.
Published: January 2013

The risk of accidents involving the catastrophic failure of storage tanks is estimated to be low, in the region of 5 × l0−6 per tank year. However, recent accidents involving major oil spills at storage facilities located in Belgium (2004) along with USA and England (2005) have shown that tank failures do nevertheless occur. Causalities of such events vary; the consequences however are ordinarily the same, incurring environmental, financial and infrastructure losses.

The normal mitigation technique employed to prevent such losses is secondary containment, usually in the form of a bund wall or earthen dyke. Researchers have investigated the reliability of such methods, examining the effects of tank failure, both theoretically and experimentally in terms of loss of containment.

A United Kingdom Health and Safety Executive (HSE) review conducted in 1997 concluded that the then available data was limited and focussed attention on the work of Greenspan and Johansson (1981) and the later work of Trobojevic and Slater (1989). This led to the HSE commissioning Liverpool John Moores University (LIMU) in 2003 to undertake a large-scale spill-modelling program with the aim of quantifying the level of overtopping and the magnitudes of the dynamic pressures on the bunds. The study examined the effect of axisymmetric releases on a total of 96 tank and bund arrangements.

Such losses have proven to be significant and in some cases the nature of the dynamic pressures has brought in to question the structural integrity of the bunds themselves. Research has since concentrated on modelling alternative modes of failure, such as directional releases, which could be considered to be the more common mode of failure likely to be encountered.

The conclusions to this work have generated additional research to investigate possible methods of mitigation that could be incorporated into the design of facilities with the ultimate aim of further reducing losses in the event of tank failure. Two promising methods have been identified, one involving modification to the primary containment (tank) with the other being a change to the design of the profile of the secondary containment (bund wall).
Government and Industry Cooperation in Practice: Azerbaijan's Experience
Authors: Hassanov Anar , Gandilov Namig , Jayson Daniel , Huseynov Tariel , Kangarli Ilkin , Ibrahimov Aghalar , Taylor Peter Mark
Published: January 2013

In recent times, Azerbaijan has seen the development of a significant modern offshore industry. The oil and shipping industries in Azerbaijan bring economic benefits but also give rise to the need for robust oil spill prevention and preparedness measures.

Azerbaijan signed the International Convention on Oil Pollution Preparedness, Response and Cooperation (OPRC) in 2004 and continues to develop and refine its national system of oil spill response. This paper discusses how the Azerbaijan government and key players in the oil industry have successfully worked together to achieve alignment in prevention, protection and response to major incidents.

The implementation of the OPRC Convention is the responsibility of the Ministry of Emergency Situations (MES) of the Republic of Azerbaijan. Within the national response system a national oil spill contingency plan has been developed. The main offshore developments in the Caspian since the 1990s have been led by BP, as operator of a number of Production Sharing Agreements. BP has implemented comprehensive oil spill response plans and is working in partnership with MES to integrate this planning into the national framework. The oil spill management systems adopted by BP and the government are compatible and commensurate with guidance published by the International Maritime Organization in 2011. These aligned management systems allow for an effective Joint Command and coordination of resources in the case of a major incident. The key to building effective oil spill preparedness are a willing dialogue, integrated command structure, joint training and exercising and upgrade of hardware and information systems' software. The cooperation between government and BP relating to offshore risks strengthens the national capacity to deal with spills risks other than from offshore platforms, including the anticipated increase of oil shipments across the Caspian Sea. Furthermore, these efforts have been supported by international organizations and the regional industry initiative, OSPRI, of which BP is a member.

The experience of Azerbaijan provides a model demonstrating how partnership between government and industry can achieve synergy and it confirms the importance of signing and implementing the OPRC Convention.
Acid Rain
Authors: Butler T.J. , Likens Gene E.
Published: January 2013

Acid rain is a popular term that can include all forms of precipitation, as well as fog and cloudwater, that is more acidic than expected from natural causes. Natural background levels of precipitation acidity tend to be around pH of 5.1–5.2. This compares with present annual average values of pH 4.3–4.4 for parts of eastern North America, and pH values less than 4.5 for large areas of Europe and eastern Asia. As pH decreases, H
+
concentration or acidity increases exponentially. Individual storms in affected areas, especially in the summer, can often produce pH values below 3.5, and cloudwater in some areas can be below pH 3.0. A more appropriate term than acid rain is “acidic deposition,” which includes both wet and dry deposition (gases and particles) of acidic compounds on the earth's surface from the atmosphere. Accurate measurements of dry deposition are unfortunately much more difficult to obtain than wet deposition. However, dry deposition can account for 10–70% of the total amount of acidic deposition.
Adaptive Designs
Authors: Flournoy Nancy , Oron Assaf P.
Published: January 2013

The designs described in this article involve treatment allocation probabilities that change according to prior data. Such designs are useful to protect from extreme results that might result from unrestricted randomization, to improve power (e.g., when group variances are unknown and unequal), when prior information is too limited to fix the sampling space a priori (e.g., regions of desirable efficacy and unacceptable toxicity are unknown). Procedures are described for studying K‐groups, but emphasis is placed on dose‐finding experiments. Some procedures involve randomization and some are deterministic given past data. Some are model based and others are nonparametric. Some procedures have a specific optimization criterion as a goal (e.g., maximize power or some other utility) and others are heuristically formulated, with large variation in ease of application and subsequent data analysis.
Air Quality
Authors: Swithenbank Jim , Sharifi Vida N. , Finney Karen N. , Goh Y. R.
Published: January 2013

Both indoor and outdoor air quality can affect health. The World Health Organisation guidance provides relevant information and measurements are required to assess the local environment. A large number of parameters should be monitored by appropriate instrumentation and sources of significant pollutants can then be investigated. Pollutants such as submicron particles that can penetrate deep into the lungs are now receiving particular attention.
American Statistical Association, Section on Statistics and the Environment
Authors: Nussbaum Barry D.
Published: January 2013

The Section on Statistics and the Environment was founded in 1990 to reflect the usage of statistical methodology in analyzing important environmental problems. The Section serves as a focal point for developing enhancements to methodology and improving training in environmental statistics. This article describes the origination and ongoing activities of the Section, including its vision, mission, and strategic plan.
Bioindicators
Authors: Mcgeoch Melodie A.
Published: January 2013

A biological indicator is a species (or group of species) that readily reflects some aspect of the state of the environment within which it is found. Bioindicators are used to detect or demonstrate the existence of a particular environmental state, and to monitor changes in that state. In this way they are used as tools to extract abiotic or biotic information from the environment so that this information can be used for making scientifically based management and policy decisions.
Monitoring, Biological
Authors: Smith Eric P.
Published: January 2013

In the environmental context, biological monitoring refers to the gathering of information on biological organisms to assess the environmental impact or the biological health of the environment. In a strict sense, the term applies to a continuing collection of data used to establish whether explicitly stated quality control conditions are being met. Other terms that are related include biological surveys, assessment, and surveillance. Biological surveys are commonly carried out by national agencies to monitor birds, whales, fish, and other organisms. Volunteer‐based surveys are an integral part of biomonitoring.
Capture–Recapture Sampling Designs
Authors: Schwarz Carl
Published: January 2013

Good study design is necessary to obtain unbiased and efficient results from capture–recapture (CR) studies. We describe the considerations necessary for successful completion of CR studies. Rather than focusing on analytical issues, we discuss the stochastic processes that give rise to the data derived from such studies. We focus on the attributes of studies necessary to ensure that the assumptions of analyses associated with CR studies are met. We hope to expose investigators to data collection issues associated with classic CR designs, and also to point out novel applications of these designs.
Catch Statistics
Authors: Sampson David
Published: January 2013

Fisheries science uses a wide variety of quantitative methods ranging from simple data tabulations to complex statistical models with hundreds of estimated parameters. Unlike the other sciences, however, in which experiments are often used successfully to evaluate competing hypotheses, many issues in fisheries are not amenable to controlled experiments because the fish are long‐lived and the fish populations are widely dispersed and suffer highly variable environmental conditions. Because fishers tend to operate in areas of high fish density where they can obtain favorable catch rates, in general the characteristics of the harvested fish will not be representative of the fish population at large. Further, different fish species often are not comparable in value and larger individuals of a given species are normally preferred to smaller ones. Hence, many of the quantitative methods in fisheries science are related to two broad problems: collecting data on the characteristics of the harvested fish and the magnitude of the harvest, and relating the harvest to the dynamics of the fish population in its entirety.
Categorical Data
Authors: Imrey Peter B. , Simpson Douglas G.
Published: January 2013

Categorical data refers to counts of events or individuals observed through some defined process and allocated to subgroups, or categories, corresponding to levels of one or more attributes. This article reviews methods for interpreting collections of such counts when they arise from apparently random environmental processes and may be treated as dependent variables relative to potentially explanatory factors or covariates. Introduction of basic terminology including measures of relative frequency and association is followed by review of the Poisson, binomial, multinomial and hypergeometric probability distributions and products thereoef, that result from conditioning upon sums of independent Poisson counts. These form the basis for modeling the random variation in observed categorical data. For modeling structural relationships, generalized linear models are first defined, and Poisson regression, logistic regression, and log‐linear models are each considered within that framework. Methods are summarized for analyzing correlated counts from observing a categorical dependent variable on the same observational units under several measurement conditions or at multiple observation times, or on multiple observational units within matched sets. These methods include weighted least‐squares functional regression, conditional logistic regression, Cochran–Mantel–Haenszel tests, generalized linear mixed models, and analyses using generalized estimating equations. Overdispersed, zero‐inflated, and ordinal data, Bayes and empirical Bayes methods, spatial modeling, exact methods and software in late 2011 are briefly discussed.
Change, Detecting
Authors: Esterby Sylvia R.
Published: January 2013

Fundamental to the assessment of the effect of human activities on the environment is the detection of changes in environmental systems. It may be of interest to detect changes occurring over time, over space, or over both time and space. Although closely linked to the determination of status and the estimation of the size and components of change, detection is the primary consideration here. Methods for detecting change include: (i) graphical methods, exploratory, and more formal; (ii) tests of hypotheses, where the hypothesis characterizes the original status; and (iii) diagnostic tests that detect departures from a specified model. Most methods considered in this article are for changes over a single dimension and will often have been developed for data collected over time. However, such methods will usually be applicable to data collected in one dimension over space. Datasets for which more than one dimension needs to be taken into account generally require more modeling and thus are less often investigated from the detection point of view.
Change‐in‐Ratio
Authors: Udevitz Mark S.
Published: January 2013

Change‐in‐ratio (CIR) methods are used to estimate parameters for ecological populations subject to differential removals from population subclasses. Subclasses can be defined according to criteria such as sex, age, or size of individuals. Removals are generally in the form of closely monitored sport or commercial harvests. Estimation is based on observed changes in subclass proportions caused by the removals.
Clustering
Authors: Chenouri Shojaeddin
Published: January 2013

Cluster analysis is concerned with the subdivision of individual objects into natural groups on the basis of collected data relating to these objects. The data may consist of observations on each object, or of perceived similarities or dissimilarities between pairs. As a statistical technique, cluster analysis is a form of “unsupervised classification,” as opposed to supervised classification, in which the groups and the group membership of the data are known, and are used to form rules to classify future observations. It is closely related to ordination, including principal component analysis and projection pursuit. These techniques are often used to justify the results of cluster analysis.
Coarse Woody Debris
Authors: Stahl Goran , Dolloff C. Andrew
Published: January 2013

Coarse woody debris (CWD), synonymous with large woody debris, is a term used to describe wood from dead trees. Although an exact definition is not available, many researchers include all pieces of wood that are at least 10 cm in diameter and 1 m in length. CWD can consist of any coarse part of a dead tree, such as trunks or parts of trunks, branches, stumps, and root wads. A distinction is often made between standing dead trees, snags, and dead trees on the ground, logs. Dead roots in the soil are generally not considered as CWD although there is no principal reason why they should not be. Challenges to the measurement and quantification of CWD range from sampling issues to multivariate statistics for studying species occurrences and communities on dead wood. A brief overview of some specific environmetrical challenges is given in this article.
Competing Risk Analysis
Authors: Gupta Ramesh C.
Published: January 2013

In studies of risk assessment due to environmental exposures, we are interested in the mortality due to a particular disease when several other diseases are acting on a person's life. The method of analyzing survival data in such a population is called “competing risk analysis.” We also have a fundamental assumption that each death takes place due to a single cause. When an individual is put on test, only his time of death and cause of death are recorded. This competing risk data provides insufficient information to determine the joint distribution of the survival times giving rise to an identifiability problem. In this article, the cause‐specific hazard functions are introduced and their estimation and testing, for modeling, both independent and dependent lifetimes are discussed. The identifiability problem is also addressed and some ways to deal with the competing risk data in the presence of association between the latent survival times are suggested.
Species Competition
Authors: Young Linda J.
Published: January 2013

Competition occurs when the interaction of two organisms has an adverse effect on both. The primary models for competition are based on the Lotka‐Volterra equations. Replacement series experiments are a standard approach to evaluating the competitive relationships of two or more species. Measures of niche overlap, such as similarity indices, are often used as initial indicators of competition although they are recognized not to be true measures of competition. The probability of a species being present may be related to environmental variables and the presence of other species using logistic regression.
Covariance Matrix Estimation (Estimated Parameters)
Authors: Wu Wei Biao
Published: January 2013

Estimation of covariance matrices of estimated parameters from common estimation procedures are considered. The consistency issue of the covariance matrix estimates is addressed for dependent and nonstationary data. As an application, hypothesis testing for trends in global annual temperature series is performed.
Databases, Health Assessment
Authors: Darnell Ross
Published: January 2013

Environmental issues regarding possible environmental pollution links to human and ecological health are becoming more numerous and controversial. The ideal approach to assessing potential health risks from environmental exposure is to conduct well‐designed, prospective, environmental, epidemiological studies. However, prospective epidemiological studies are difficult and expensive to undertake, and even retrospective studies can be prohibitively complex. Reliable environmental data are not easy to find and often they may not have been collected in a manner that makes them easy to use. The availability of data increases the risk of identifying single units using increasingly powerful search engines by ill‐intentioned users. The increasing public availability of health and environmental data raises the risk of identifying individuals, forcing data owners to develop techniques to reduce this risk.
Decision Support Systems, Environmental
Authors: Paul Nathanail C.
Published: January 2013

Decisions involving environmental aspects are complex. The underlying environmental processes are tackled by teams that are invariably multidisciplinary in nature and involve sundry specialists: earth, physical, chemical, geochemical, biological, benthic, and ecological sciences. Many decisions, such as water resources allocation, irrigation and agricultural practices, toxic waste management, industrial effluent regulation, acid rain mitigation, and climate change accommodation are interrelated. The solution or mitigation of one problem usually affects another. In addition, the constraints to these solutions are legion: economic considerations for remedial costs, social values of clean water and air, political and public opinions on biodiversity, and so on. Environmental decision makers and policy advisors need to consider all these complex factors in their decision‐making and policy‐building processes. The purpose of this article is to discuss the tools that an environmental manager may need to support decision‐making processes. With the advent of information technology, this article focuses on the possible use of computer systems to provide the support. Their design, implementation, advantages, and disadvantages are discussed and examples of applications and future directions are given. These systems are calledenvironmental decision support systems.
Defoliation
Authors: Candy Steven G. , Zalucki Myron P.
Published: January 2013

From ancient times, mankind has attempted either to harness or to prevent defoliation of trees and plants. The positive and negative impact of defoliation by invertebrates (chiefly insects), vertebrates, plant diseases, or abiotic factors such as air pollution is an integral part of agriculture, forestry, and natural resource management. Defoliation is “an unseasonable reduction in the foliage cover of a plant due to attacks by insects or fungal disease, or as a result of other factors such as drought, storms, or chemicals in the atmosphere.” Defoliation encompasses partial or complete loss of the plant's foliage and individual leaves. The most significant impacts of natural defoliation are crop losses in agriculture and production forestry and, for native plant communities, possible changes in structure and species composition and loss of amenity values. It is not possible to review in this article the huge amount of information available on defoliation. In terms of measurement, estimation, or prediction, there are a number of commonalties across the range of activities in which quantification of defoliation is required.
Kernel Density Estimation
Authors: Horová Ivana
Published: January 2013

The probability density function is a fundamental concept in statistics. Density estimation is the reconstruction of the density function from a set of observed data and it can give valuable indication of such features as skewness and multimodality in the data.
Discriminant Analysis
Authors: Mclachlan Geoffrey J.
Published: January 2013

In this article, we consider discriminant analysis where classification is undertaken in the context where there are a number of classes and the observed data (the so‐called training data) are of known classification with respect to these classes. We consider both parametric and nonparametric approaches to the formation of allocation rules from the available training data. The coverage starts with Fisher's linear discriminant function, which was the initial attempt to perform discriminant analysis in its modern guise. The estimation of the error rates of the sample‐based rules so formed are considered. Particular attention is given to the classification of high‐dimensional data where the number of training observations is small relative to the large number of available variables.
E
arth
O
bservation
P
rogrammes (
EOP
)
Authors: El‐shaarawi Abdel
Published: January 2013

The Earth Observation Programme generates observations on global environmental issues such as the water cycle, sea‐ice thickness, and climate variability.
EcosystemMonitoring
Authors: Mcclintock Brett
Published: January 2013

The world's population has increased 6 times over the past 200 years. It has doubled over the past 40 years. Air and water pollution, climate change, loss of species, soil erosion and salinization, desertification, loss of forest, and a range of other undesirable environmental alterations have accompanied this unprecedented increase in human numbers. While the rate of population growth is declining, human pressure on the environment will continue to increase as human standards of living and per capita consumption increase, and it is clear that a fundamental change must occur in the relationship between humans and the global ecosystem if we are to avoid highly undesirable environmental change. Development of a sustainable relationship between humans and the environment requires an understanding of, and respect for, both human needs and desires, and the structure and functioning of the world's ecosystems. Policies and resource management practices must be developed that sustain desired ecosystem conditions and functions. To ensure that these policies and practices are effective, the condition of the world's ecosystems must be monitored.
Sampling, Environmental
Authors: Stehman Stephen V. , Overton W. Scott
Published: January 2013

Environmental sampling encompasses methods for collecting and analyzing data to address questions in diverse fields such as ecology, environmental engineering, environmental policy, fisheries, forestry, and wildlife science. The goal of sampling is to estimate collective properties or parameters (e.g., means, totals, and proportions) characterizing the attributes or measurements defined on a universe. A universe may consist of discrete objects such as lakes, wetlands, stream segments, forest stands, plant or animal populations, environmental organizations, or recreational users, or a universe may be defined spatially, for example by delineating an area on a map. Environmental sampling objectives typically address questions of status and/or trend. Status refers to current attributes of the universe. For example, how many acidic lakes are there in the northeast United States potentially sensitive to acidification, or how many individuals of a rare plant population exist? Trend focuses on how attributes of a universe are changing over time. Are certain amphibian populations declining in South American forests? Is tree disease increasing following a damaging ice storm? How much agricultural land is being converted to residential and commercial use? These collective properties of status and trend are estimated from a sample, which is a subset of the universe. A sampling strategy consists of a sampling design, which is the protocol for selecting the subset of the sample, and the estimator (formula) of a parameter. Good environmental sampling practice requires a judicious choice of both sampling design and estimator to create a sampling strategy that is practical and yields precise estimates of parameters.
E
uropean
E
nvironment
A
gency (
EEA
)
Authors: El‐shaarawi Abdel
Published: January 2013

The decision to establish European Environment Agency (EEA) was made by the European Union in 1990 and it began its work in earnest in 1994. Its objective is to provide for decision‐makers and the public sound and independent information on the environment. It has a total of 32 member countries and 7 cooperating countries.
ExceedanceOverThreshold
Authors: Drees Holger
Published: January 2013

We consider methods from extreme value statistics to fit threshold models to univariate or multivariate samples. Moreover, the influence of serial dependence between observations on the estimation accuracy and on quantities of interest, such as return levels, is discussed.