The natural resources of San Diego Bay; Their status and future

The study of the natural resources of San Diego Bay is a part of a high priority inventory and assessment program conducted by the Department of Fish and Game. This report is a guide for citizens, planners, administrators, and all others interested in the use and development of coastal lands and waters. It documents the status and future of natural resources that should be a part of the inheritance of future generations. References appended provide the interested and concerned reader with sources of more specific information. One of a scheduled series, this publication follows similar documents on Upper New-port Bay (Orange County), Goleta Slough (Santa Barbara County), Bolinas Lagoon (Marin County), and Elkhorn Slough (Monterey County). Preparation of this report has been supported by Fish and Wild- Life Preservation funds and by Pittman-Robertson Federal Aid to wildlife programs. (124 pp.

#Snitches Get Stitches: Witness Intimidation in the Age of Facebook and Twitter

In order to better understand witness intimidation in the age of social media, one must examine both the forms it has taken as well as the response by law enforcement and the criminal justice system. As this article points out, the digital age has brought with it a host of new ways in which witnesses may be subjected to online harassment and intimidation across multiple platforms, and those means have been used to target not only victims and fact witnesses but even prosecutors and expert witnesses as well. The article will also examine potential responses to the problem of witness intimidation via social media, including proposed legislation. And while the focus of this article is on this problem as it currently stands in the United States, it should be remembered that just as social networking is a worldwide phenomenon, the use of such platforms for witness intimidation is an international problem. For example, Arab women living in the United States who have filed domestic abuse charges against their husbands have reported members of their families overseas being intimidated and harassed through social media postings as a form of pressure on the complaining victim. And in Mexico, drug cartels use social media to harass and target those who report their actions

The natural resources of Carpinteria Marsh: their status and future

The purpose of this report is: 1) to document the natural resources of Carpinteria Marsh, 2) outline the uses those resources receive, 3) enumerate the problems and conflicts of use that affect those resources, and 4) recommend measures that will protect and enhance the marsh and its resources. It is intended as a guide for citizens, planners and administrators of all private and public entities interested in the status and future of the marsh. This report has been prepared under contract to and fully funded by the Office of Biological Services of the U.S. Fish and Wildlife Service. The goals and purpose of this federal office are to review the impact on fish and wildlife resources of land, mineral and water development practices, such as offshore oil and gas exploration, development and production; construction of inshore pipeline canals and refineries; power plant construction/operation and urban development. This report, and five other southern California reports, covering Agua Hedionda (San Diego County), Anaheim Bay-Huntington Harbor (Orange County), Mugu Lagoon (Ventura County), the Northern Santa Barbara County Coastal Wetlands and the Nipomo Dunes and Wetlands (San Luis Obispo County), are scheduled to be part of the Department's "Coastal Wetland Series" that includes reports on the natural resources of Upper Newport Bay (Orange County), Goleta Slough (Santa Barbara county), Bolinas Lagoon (Marin County), Elkhorn Slough (Monterey County), San Diego Bay and Los Penasquitos Lagoon (San Diego County), Morro Bay (San Luis Obispo County), Humboldt Bay and the Eel River Delta (Humboldt County), Lake Earl and the Smith River Delta (Del Norte County) and Bodega Harbor (Sonoma County). (103pp.

The natural resources of Agua Hedionda Lagoon

This report has been prepared under contract to and fully funded by the Office of Biological Services of the U. S. Fish and Wildlife Service. The goals and purpose of this federal office are to review the impact on fish and wildlife resources of land, mineral and water development practices, such as offshore oil and gas exploration, development and production; construction of inshore pipeline canals and refineries; power plant construction/operation and urban development. This report, and five other southern California reports, covering Carpinteria Marsh (Santa Barbara County), Anaheim Bay-Huntington Harbor (Orange County), Mugu Lagoon (Ventura County), the Northern Santa Barbara County Coastal Wetlands, and the Nipomo Dunes and Wetlands (San Luis Obispo County), are scheduled to be part of the Department's "Coastal Wetland Series" (see inside front cover). (154 pp.

Surface displacements resulting from magma-chamber roof subsidence, with application to the 2014-2015 Bardarbunga-Holuhraun volcanotectonic episode in Iceland

The conditions which lead to caldera collapse are still poorly constrained. As there have only been four, possibly five, well-documented caldera forming events in the past century, the geodetic signals produced during chamber roof subsidence, or chamber volume reduction (shrinkage) in general, are not well documented or understood. In particular, when two or more geodetic sources are operating and providing signals at the same time, it is important to be able to estimate the likely contribution of each. Simultaneous activities of different geodetic sources are common and include pressure changes in magma chambers/reservoirs occurring at the same time as dyke emplacement. Here we present results from numerical models designed to simulate the subsidence of a magma-chamber roof, either directly (chamber shrinkage) or through ring-fault displacement, and the induced surface deformation and crustal stresses. We consider chamber depths at 3 km, 5 km, and 7 km below the crustal surface, using both non-layered (isotropic) and layered (anisotropic) crustal models. We also model the effects of a caldera lake and of a thick ice cover (ice sheet) on top of the caldera. The results suggest that magma-chamber roof subsidences between 20 m and 100 m generate large (tens of centimetres) vertical and, in particular, horizontal displacements at the surfaces of the ice and the crust out to distances of up to tens of kilometres from the caldera/chamber centre. Crustal layering tends to reduce, but increasing chamber depth to enlarge, the horizontal and vertical surface displacements. Applying the results to the ice subsidence in the Bardarbunga Caldera during the 2014-2015 Bardarbunga-Holuhraun volcanotectonic episode indicates that the modelled ice displacements are less than those geodetically measured. Also, the geodetically measured crustal displacements are less than expected for a 60 m chamber-roof subsidence. The modelling results thus suggest that only part of the ice subsidence is due to chamber-roof subsidence, the other part being related to flow in the ice. We show that such a flow is likely within the caldera as a result of the stress induced by the 45-km-long regional dyke emplaced (primarily in vertical magma flow) during the episode. This conclusion is further supported by the model results suggesting that the ring-fault (piston-like) displacements must have been much less than the total 60 m ice subsidence, or else faults with tens-of-metres displacements would have cut through the ice (these are not observed). We suggest that the ring-fault subsidence was triggered by small doming of the volcanic field and system hosting the Bardarbunga Caldera and that this doming occurred as a result of magma inflow and pressure increase in a deep-seated reservoir. The doming is confirmed by GPS measurements and supported by the seismicity results. The magmatic pressure increase in the reservoir was, in terms of the present model, responsible for the regional dyke emplacement, the Holuhraun eruption, and part of the stress concentration around, and displacement of, the Bardarbunga Caldera

Caldera faults capture and deflect inclined sheets:an alternative mechanism of ring dike formation

The subsurface structures of caldera ring faults are often inferred from numerical and analog models as well as from geophysical studies. All of these inferred structures need to be compared with actual ring faults so as to test the model implications. Here, we present field evidence of magma channeling into a caldera ring fault as exhibited at Hafnarfjall, a deeply eroded and well-exposed 5-Ma extinct volcano in western Iceland. At the time of collapse caldera formation, over 200 m of vertical displacement was accommodated along a ring fault, which is exceptionally well exposed at a depth of approximately 1.2 km below the original surface of the volcano. There are abrupt changes in the ring fault attitude with depth, but its overall dip is steeply inward. Several inclined sheets within the caldera became arrested at the ring fault; other sheets became deflected up along the fault to form a multiple ring dike. We present numerical models showing stress fields that encourage sheet deflection into the subvertical ring fault. Our findings provide an alternative mechanical explanation for magma channeling along caldera ring faults, which is a process likely to be fundamental in controlling the location of post-caldera volcanism

Numerical modelling of triple-junction tectonics at Karlıova, Eastern Turkey, with implications for regional magma transport

Few places on Earth are as tectonically active as the Karlıova region of eastern Turkey. In this region, complex interactions between the Arabian, Eurasian and Anatolian plates occur at the Karlıova Triple Junction (KTJ). The relationship between tectonics and magma propagation in triple-junction tectonic settings is poorly understood. Here we present new field and numerical results on the mechanism of magma propagation at the KTJ. We explore the effects of crustal heterogeneity and anisotropy, in particular the geometry and mechanical properties of many faults and layers, on magma propagation paths under a variety of tectonic loadings. We propose that two major volcanic centres in the area, the Turnadağ volcano and the Varto caldera, are both fed by comparatively shallow magma chambers at depths of about 8 km, which, in turn, are fed by a single, much larger and deeper reservoir at about 15–18 km depth. By contrast, the nearby Özenç volcanic area is fed directly by the deeper reservoir. We present a series of two-dimensional and three-dimensional numerical models showing that the present tectonic stresses encourage magma-chamber rupture and dyke injection. The results show that inversion tectonics encourages the formation of magma paths as potential feeder dykes. Our three-dimensional models allow us to explore the local stresses induced by complex loading conditions at the Karlıova triple junction, using an approach that can in future be applied to other similar tectonic regions. The numerical results indicate a great complexity in the potential magma (dyke) paths, resulting from local stresses generated by interaction between mechanical layers, major faults, and magma chambers. In particular, the results suggest three main controls on magma path formation and eventual eruptions at KTJ: (1) the geometry and attitude of the associated faults; (2) the heterogeneity and anisotropy of the crust; and (3) mechanical (stress) interactions between deep and shallow magma chambers

Combination of mesoscale and synoptic mechanisms for triggering an isolated thunderstorm: Observational case study of CSIP IOP 1

Copyright @ 2007 AMSAn isolated thunderstorm formed in the southern United Kingdom on 15 June 2005 and moved through the area where a large number of observational instruments were deployed as part of the Convective Storm Initiation Project. Earlier, a convergence line had formed downstream of Devon in the southwest of the United Kingdom in a southwesterly airflow, along which a series of light showers had formed. The depth of these showers was limited by a capping inversion, or lid, at around 2.5 km. The deep thunderstorm convection developed from one of these showers when the convection broke through the lid and ascended up to the next inversion, associated with a tropopause fold at around 6 km. A series of clear-air reflectivity RHIs are used to map the height of the capping inversion and its lifting resulting from the ascent along the convergence line. The origins of the lid are tracked back to some descent from the midtroposphere along dry adiabats. The strength of the lid was weaker along a northwest-to-southeast-oriented region located behind an overrunning upper cold front. The transition from shallow to deep convection occurred where this region with a weaker lid intersected the region with a raised lid, oriented southwest to northeast, downstream of Devon. A very high resolution forecast model that is being developed by the Met Office predicted the isolated thunderstorm successfully. This success depended on the accurate representation of the following two scales: the synoptic-scale and the surface-forced mesoscale convergence line. The interaction between these scales localized the convection sufficiently in space and time for the initiation and subsequent development to be highly predictable despite the relatively poor representation in the model of processes at the cloud scale.This work was funded from the Natural Environment Research Council and the Met Office National Meteorology Programme

The natural resources of San Dieguito and Batiquitos Lagoons

The California Department of Fish and Game has played a central role in attempting to protect and enhance the remaining 25% of southern California wetlands which have survived the ingress of urbanization and commercial development since 1900 (U.S. Dept. Interior, 1972). To this end, the Department has published a series of reports documenting California's coastal wetlands resources, including four covering wetlands in southern California (Upper Newport Bay, Frey et al., 1970; Goleta Slough, Speth et al., 1970; Los Penasquitos Lagoon, Mudie et al., 1974; and San Diego Bay, Browning et al., 1973). The following report is an extension of that effort. (131pp.

Natural resources of Lake Earl and Smith River Delta

The Lake Earl/Smith River Delta area is a key coastal wetland situated in northern California. The Lake and Delta have retained much of their value to wildlife and serve as an important link in a chain of such wetlands that extend southward along the Pacific Ocean from Alaska to South America. Millions of water-associated birds of the Pacific Flyway utilize these areas as feeding and resting stops along their migration paths. In California, these wetlands also serve as a significant portion of the available wintering grounds for a major share of the birds within the flyway. The Smith River is also one of the State's most productive salmon and steelhead streams. Anadromous fish produced here provide thousands of angler use days to sport fishermen and contribute substantially to the commercial fishing catch off the northern coast. Because of the importance of coastal wetlands to the fish and wildlife of California, the Department of Fish and Game has initiated a high priority statewide inventory and assessment of these wetlands. This publication is an integral part of that program. This report identifies specific resources and uses; directs attention to problems; and recommends courses of action needed to insure resource protection. It is intended as a guide for citizens, planners, administrators and other interested in the use and development of California's coastal land and waters. (132pp.