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Ecological and economic systems are open systems that require energy to change the thermodynamic states of materials from naturally occurring to more valued forms. These changes are accompanied by information flows and changes in the order of systems and their surroundings. In this paper, thermodynamics is used to assess these system changes and relate them to the knowledge present in a system. Particular emphasis is given to (1) the fundamental relationships among material, energy and information flows, and changes in order and knowledge, (2) the role of equilibrium and non-equilibrium thermodynamics in assessing system change, (3) the increasing role of material and energy flows through economic systems, and (4)...
The purpose of the Coral Reef Evaluation and Monitoring Project (CREMP) is to monitor the status and trends of selected reefs in the Florida Keys National Marine Sanctuary(FKNMS). CREMP assessments have been conducted annually at fixed sites since 1996 and data collected provides information on the temporal changes in benthic cover and diversity of stony corals and associated marine flora and fauna. The core field methods continue to be underwater videography and timed coral species inventories. Findings presented in this report include data from 109 stations at 37 sites sampled from 1996 through 2008 in the Florida Keys and 1999 through 2008 in the Dry Tortugas. The report describes the annual differences (between...
Categories: Data; Types: NetCDF OPeNDAP Service; Tags: Coral Reef Evaluation and Monitoring Project (CREMP), about, absence, accepted, acceptedNameAuthorship, All tags...
This paper revisits the recent developments in biofuel markets and their economic, social and environmental impacts. Several countries have introduced mandates and targets for biofuel expansion. Production, international trade and investment have increased sharply in the last few years. However, some analysts linked biofuels to the 2007–2008 global food crisis. Existing studies diverge on the magnitude of the projected long-term impacts of biofuels on food prices and supply, with studies that model only the agricultural sector showing higher impacts and studies that model the entire economy showing relatively lower impacts. In terms of climate change mitigation, biofuels reduces GHG emissions only if GHG emissions...
Natural gas is an important energy source for power generation, a chemical feedstock and residential usage. It is important to analyse the future production of conventional and unconventional natural gas. Analysis of the literature determined conventional URR estimates of 10,700–18,300 EJ, and the unconventional gas URR estimates were determined to be 4250–11,000 EJ. Six scenarios were assumed, with three static where demand and supply do not interact and three dynamic where it does. The projections indicate that world natural gas production will peak between 2025 and 2066 at 140–217 EJ/y (133–206 tcf/y). Natural gas resources are more abundant than some of the literature indicates.
Categories: Publication; Types: Citation; Tags: Long-term, energy, security, service, value
Proppants for hydraulic fracturing are subjected to very severe conditions of stress, temperature, and chemical environment while they are expected to maintain their structural integrity for a period of many years. The performance of these proppants over time at simulated in-situ conditions has been a topic of laboratory investigation for several years, but in many cases the real conditions exceed the capabilities of the laboratory apparatus. To determine the proppant behavior under real reservoir conditions, production history and pressure buildup tests of four fractured wells have been analyzed. The reservoir conditions of these wells are so severe, that it was almost impossible to simulate them in the laboratory....
Categories: Publication; Types: Citation; Tags: Long-term, energy, security, service, value
Some theoretical results concerning the nature of the relationship between the scientific quality and economic value of imperfect weather forecasts are obtained. A prototype multistage decision-making model is considered, involving only two possible actions and two possible states of weather. This particular form of model is motivated by a real-world application known as the fruit-frost problem. For an infinite-horizon, discounted version of this model it is shown that economic value remains zero below a forecast quality threshold and then rises monotonically but nonlinearly above this threshold. In particular, the relative sensitivity of economic value to changes in the quality of forecasts increases as perfect...
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This polygon feature class shows the spatial extent and boundaries of Areas of Critical Environmental Concern that have become officially designated by the BLM. These polygon features were previously in a pre-designated status (i.e. being considered as areas to be eventually designated as official ACEC designated polygonst). Once these polygon feature left the Pre-Designated phase (transitioned from a Considered to Designated status), they were removed from the ACEC Pre-designated polygon feature class and placed in this ACEC Designated polygon feature class. This dataset is a subset of the official national dataset, containing features and attributes intended for public release and has been optimized for online...
Some theoretical results concerning the nature of the relationship between the scientific quality and economic value of imperfect weather forecasts are obtained. A prototype multistage decision-making model is considered, involving only two possible actions and two possible states of weather. This particular form of model is motivated by a real-world application known as the fruit-frost problem. For an infinite-horizon, discounted version of this model it is shown that economic value remains zero below a forecast quality threshold and then rises monotonically but nonlinearly above this threshold. In particular, the relative sensitivity of economic value to changes in the quality of forecasts increases as perfect...


map background search result map search result map Coral Reef Evaluation and Monitoring Project Florida Keys 1996 BLM National Designated Areas of Critical Environmental Concern Polygons Coral Reef Evaluation and Monitoring Project Florida Keys 1996 BLM National Designated Areas of Critical Environmental Concern Polygons