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Abstract: We examined short-term phytoplankton and sediment dynamics in Tampa Bay with data collected between 8 December 2004 and 17 January 2005 from optical, oceanographic, and meteorological sensors mounted on a coastal oceanographic tower and from satellite remote sensing. Baseline phytoplankton (chlorophyll-a, Chl) and sediment concentrations (particle backscattering coefficient at 532 nm, bbp(532)) were of the order of 3.7 mg m−3 and 0.07 m−1, respectively, during the study period. Both showed large fluctuations dominated by semidiurnal and diurnal frequencies associated with tidal forcing. Three strong wind events (hourly averaged wind speed >8.0 m s−1) generated critical bottom shear stress of >0.2 Pa and suspended bottom sediments that were clearly observed in concurrent MODIS satellite imagery. In addition, strong tidal current or swells could also suspend sediments in the lower Bay. Sediments remained suspended in the water column for 2–3 days after the wind events. Moderate Chl increases were observed after sediment resuspension with a lag time of ˜1–2 days, probably due to release of bottom nutrients and optimal light conditions associated with sediment resuspension and settling. Two large increases in Chl with one Chl > 12.0 mg m−3 over ˜2 days, were observed at neap tides. For the study site and period, because of the high temporal variability in phytoplankton and sediment concentrations, a monthly snapshot can be different by −50% to 200% from the monthly “mean” chlorophyll and sediment conditions. The combination of high-frequency observations from automated sensors and synoptic satellite imagery, when available, is an excellent complement to limited field surveys to study and monitor water quality parameters in estuarine environments. [Copyright &y& Elsevier]

Abstract: Two algorithms designed to detect deepwater oceanic features and arbitrary edge profiles were tuned to automatically delineate fronts in coastal waters off west–central Florida using satellite-derived sea surface temperature (SST), chlorophyll-a concentration (Chl), normalized water-leaving radiance (nL w ), and fluorescence line height (FLH) images during select periods in the spring and fall of 2004 and 2005. The dates correspond to recreational king mackerel, Scomberomorus cavalla, tournaments. A histogram-based algorithm was useful to detect coastal surface SST, nL w , and FLH fronts, specifically. A gradient-based algorithm, with a smaller kernel box of 3×3 pixels, best identified nearshore (<10 m depth) features in Chl images at the mouth of Tampa Bay, but was less effective for fronts farther offshore where gradients were weaker. Local winds and tide levels estimated from a coastal observing buoy, and bathymetric gradients were examined to help understand the factors that influenced front formation and stability. Periods of strong and variable winds led to front movement of up to 10 km per day or dissipation within 2–3 days in over 80% of the fronts detected in SST, Chl, nL w , and FLH imagery. Short episodes of less variable wind velocities typically led to more stable and stationary fronts, within 3–5 km, for up to four days. The occurrence of fronts closely associated with the coastal bathymetry, namely at the 20 m and 30 m isobaths, was significantly higher in the fall SST imagery and in the spring Chl imagery. Fall SST fronts related to bathymetric gradients likely resulted from progressive cooling of the water with depth. Stronger Chl and nL w 443 gradients at the mouths of estuaries in the fall compared to the spring were attributed to increased precipitation and periods of stronger winds or tides. The FLH imagery was most useful in delineating coastal algal blooms. The automatic front detection techniques applied here can be an important tool for resource managers to track coastal oceanographic features daily, over synoptic spatial scales. [Copyright &y& Elsevier]

The NOAA Buoy model is currently used to estimate the air–sea transfer rates of highly soluble gases over coastal water bodies, such as Tampa Bay, using offshore meteorological measurements. Since a goal of the BRACE study was to improve estimates of nitrogen deposition over Tampa Bay, our objective was to investigate if the model accurately predicts gas transfer when shoreline input data are used in lieu of offshore measurements. To accomplish this objective, we compared over-water measurements of sensible heat with NOAA Buoy model predictions using both offshore and shoreline meteorology. In the summer months, the apparent daytime influence of land surface heating on air temperature produces a higher air than water temperature at the shoreline. For the NOAA Buoy model, this yields stable atmospheric conditions and thus under-predicts the over-water exchange rates for a shallow estuary. If the data records are removed from the model for periods when air temperature is 4.8K greater than the water temperature, the shoreline and over-water transfer rates are in reasonable agreement. [Copyright &y& Elsevier]

Because estuaries and coastal regions are particularly susceptible to nutrient over-enrichment due to their close proximity to source-rich regions, a goal of the BRACE study was to improve estimates of nitrogen air/sea transfer rates in the Tampa Bay Estuary. Our objective was to critically evaluate two air/sea gas exchange models to determine their efficacy for use in a coastal region, with the ultimate goal of improving nitrogen exchange estimates in Tampa Bay. We used meteorological data and oceanographic parameters collected hourly at an instrumented tower located in Middle Tampa Bay, Florida. The data was used to determine the friction velocity and the turbulent flux of heat and moisture across the air/sea interface and then compared with modeled parameters at the same offshore site. On average both models underpredicted sensible heat flux and there was considerable scatter in the data during stable conditions, indicating that nitrogen gas exchange rates may also be underestimated. Model improvement, however, was observed with friction velocity comparisons. Model inter-comparisons of sensible heat flux and friction velocity suggest excellent agreement between the TOGA COARE and the NOAA Buoy models, but model estimated heat transfer coefficients and latent heat fluxes did not agree as well. Based on our analysis, we conclude that both models are suitable for use in a coastal environment to estimate nitrogen air/sea gas exchange, although the NOAA Buoy model requires fewer meteorological inputs. However, if the purpose is to conduct more sophisticated microscale modeling of air/sea interactions, we recommend the TOGA COARE model. [Copyright &y& Elsevier]

Consideration of the dependence of various components of the sea-surface heat and momentum fluxes on sea surface temperature (SST) leads to an explanation for the observed reduction in the horizontal temperature gradients in the uppermost layer of the ocean (a few to 10 m in depth). Horizontal temperature gradients within the mixed layer can be masked by a near-surface layer of warm water. This camouflage of horizontal temperature gradients has importance for the remote sensing of SST used by the fishing industry, for the estimation of acoustic transmission, and for the forecasting of hurricane development, among many uses of SST data. Diurnal warming conditions in the Straits of Florida are examined by a simulation calculation and by analysis of observations obtained on moorings deployed on the south-east Florida shelf. When there is net heating (i.e., the solar input is stronger than the combined latent, sensible and longwave radiative heat losses) the originally warmer water experiences less heating than the colder water, leading to a weakening of the horizontal SST gradients as seen by surface buoys or satellites. The warmer water also experiences more mixing and therefore less increase in temperature. The strongest effect of the diurnal heating on wind stress occurs when the SST starts out cooler than the air temperature and the atmosphere is stably stratified. Diurnal warming can then rapidly increase the SST above the air temperature because of reduced wind stress and reduced upper-ocean mixing. After that the wind stress increases as convectively driven turbulence contributes to the atmospheric exchange. [ABSTRACT FROM AUTHOR]

Abstract: Sampling of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) at the Gandy Bridge monitoring site between May and August 2002 provided preliminary ambient air concentrations and dry deposition rates for Tampa Bay. The HiC-IOGAPS dramatically improved the recovery of lower molecular weight gas and particle PAHs, as evidenced by the recoveries of PAHs in back-up denuders and filter packs. Total PAH (gas+particle) concentrations ranged from 80 to 190ngm-3. Concentrations of naphthalene, acenaphthene, fluorene, phenanthrene, fluoranthene, and pyrene were consistently higher than concentrations of the remaining 10 PAHs. Assuming an unidirectional flux of these compounds from air to water, the estimated total (gas+particle) dry deposition flux was 11.5μgm-2d-1, or 6.7μgm-2d-1 if naphthalene is excluded. [Copyright &y& Elsevier]

Focuses on a study which summarized estimates of volume transport and property distributions through the Mozambique Channel and offered additional estimates and measurements based on acquired hydrographic and data. Historical background and interpretation; Results of the study; Float speed and velocity statistics.

The issue of sustainable energy consumption in the socio-economic system has been widely investigated in recent studies. Embodied energy transfer is also part of the normal economic pattern. To evaluate the sustainability of a system, it is important to consider not only the growth of the system as an indicator, but also the development of the system's structure. Growth and development are two phenomena that need to be quantitively measured because these phenomena closely reflect sustainability. However, little research has studied the effects of sectoral level on growth and development. This research addresses growth and development from a network perspective in order to assess the sectoral effects on system characteristics by using information-based ecological network analysis (IENA) and a hypothetical embodied energy network model. In this study, taking the Australian industrial system as an example, Australian national input–output data and industrial consumption data are used to establish the embodied energy network based on Australian industries. The research constructs an embodied energy cycle network with seven major industries and uses a hypothetical extraction method to establish a hypothesis network for each sector. Then the research compares the hypothetical networks with the original embodied energy network. The differences represent the sectoral effects on the growth and development of the embodied energy network. By using the IENA method with the hypothetical network model, the contribution of a single specific sector can be quantified. Analytical results reveal that the sectoral increases in the volume of the network do not reflect system sustainability, while system sustainability improvement requires sectoral contributions not only to system volume but also to an increase in network organization. The research develops a sectoral-level model to identify the key drivers in the identified system from the network perspective. The results show the sectors with high levels of self-embodied energy flows make high contributions to the improvement of system sustainability in the Australian embodied energy network. [ABSTRACT FROM AUTHOR]

Owing to the advantages of high construction efficiency, prefabricated residential buildings have been of increasing interest in recent years. Against the background of global heating, designing low-carbon facades for prefabricated residential buildings has become a focus. The main challenge for this research is in designing windows for prefabricated residential buildings that can lead to the best performance in carbon emissions. The purpose of this paper is to summarize window design advice for prefabricated residential building facades with low-carbon goals. This paper adopts the single control variable research method. Building energy consumption and carbon dioxide emissions under different conditions comprise the primary data used in the study. In the process of achieving the research aim, this study firstly extracts the window design elements of prefabricated residential facades. Secondly, objective function formulas are established and a basic model is built for obtaining data. Thirdly, data results are analyzed and window design advice is put forward under the condition of a low-carbon goal. This paper discusses that the optimal window-to-wall ratio (WWR) with a low-carbon orientation is around 0.15, and compares it innovatively with the optimal WWR under an energy-saving orientation at around 0.38. The research results of this paper can deepen the understanding of architectural low-carbon design and play a guiding role for architects. [ABSTRACT FROM AUTHOR]

Energy sustainability has great importance in the development of the economy and society since energy is a necessary driving force for economic growth. The construction sector accounts for a greater percentage of global energy consumption than most other sectors. The structure of exports in the current trade pattern has affected the transmission of sectoral embodied energy through changes in regional economies. This paper uncovers the composition of productions for gross exports and examines embodied energy from the viewpoint of value added through a case study in the construction sector. Multi-regional input–output tables have been used to process the data relevant to economic trade and energy input, while the production of gross exports in 40 countries has been decomposed into the exports of value-added trade and the exports of vertical specialisation trade based on data from world input–output tables. The decomposition and reorganisation clearly show the pathways and composition in the trade activities of gross exports. The embodied energy of value-added exports accounted for 60–90% of gross exports in the construction sectors of 37 countries. The framework for sharing production in the construction sector still dominated the connections among many countries, especially the trade relationships between large economies. In the process of vertical specialisation trade, the foreign value added of the construction sector was still limited by significant events such as the global financial crisis. The construction sectors were ranked between 5 and 11 in all 35 domestic sectors in 34 countries as measured by the total export of embodied energy. So, the creation of high value added is enhanced by improvement in energy efficiency in the construction sector. However, the reduction of energy consumption in the construction sector may indirectly increase energy consumption in its upstream sectors because of the connection between exports and related production. The balance between energy consumption and creation of value added in exports is an important consideration for government supervision and sectoral development. Local construction markets need to strengthen their ability in the supply of intermediate goods, which benefits value-added exports and domestic demand. Moreover, developing national and international supply chains can positively offset the impact of the imbalanced distribution of globalised production. • Decomposition reveals the pathways of energy flows embodied in vertical specialisation and value-added trade. • The development of technology-intensive products is encouraged in countries with high embodied energy intensity. • The creation of value added is mainly driven by the direct requirements in export trade. • The construction sector is located in high positions in 35 domestic sectors when measured by the exports of embodied energy. [ABSTRACT FROM AUTHOR]

Energy is a vital necessity in driving the development of the global economy, national industries, and even services for people. The construction sector consumes a high proportion of energy and this requires improvement for its sustainable development. Due to the growth of multilateral trade, the energy flows embodied in the global trade network have become more complex, and the energy embodied in the exports of vertical specialisation trade has increased rapidly in satisfying domestic final energy consumption. This paper traces the original creation of the value added in the national construction sectors in the global value chain based on their energy consumption in the production of gross exports. The gross exports are broken down into domestic and foreign value-added exports, and the energies embodied in these two types of exports are analysed and compared. The exports of foreign value added is mainly indicated by the exports of vertical specialisation trade. Net outflows in domestic value-added exports and net outflows in exports of vertical specialisation trade are then used in measurement of sectoral position in the global value chain. The results show that the overall trend of domestic value-added exports continues to increase in the construction sectors of the majority of countries. Russia, China, and the USA performed significantly in relation to the quantity of energy embodied in domestic value-added exports. Moreover, the effect of technology needs to be considered in the production of exports for vertical specialisation trade. The distribution of the net outflow is similar to the performance of the energy embodied in domestic content in the construction sector. The net inflow of embodied energy was positive in all countries, which indicates that the energy embodied in exports of vertical specialisation trade was mainly derived from the support of the international market. Only one country had a lower net outflow of embodied energy than in gross exports. For policymakers, a policy guiding the exports of the construction sector needs to be considered in relation to the origins of the value added. The export structure in the construction sector is encouraged to move toward technology-intensive, instead of labour-intensive products in order to enhance sustainable energy development. • Energies embodied in domestic value-added exports in the construction sector • Energies embodied in vertical specialisation trade in the construction sector • Identifying the origins of value-added creation and its assimilation by destinations • Inflow and outflow of embodied energies in gross exports of the construction sector • Positioning construction sectors in the global value chain by energy transmission [ABSTRACT FROM AUTHOR]

A coastal risk assessment system simulates the basic physical mechanisms underlying contaminant transport in Tampa Bay. This risk assessment system, comprised of a three-dimensional numerical circulation model coupled to a Lagrangian particle tracking model, simulates the transport and dispersion of a toxic dinoflagellate bloom. Instantaneous velocity output from the circulation model drives the movement of particles, each representing a fraction of a K. brevis bloom, within the model grid cells. Hindcast simulations of the spatial distribution of the K. brevis bloom are presented and compared with water sample concentrations collected during the peak of the bloom. Probability calculations, herein called transport quotients, allow for rapid analysis of bay-wide K. brevis transport showing locations most likely to be impacted by the contaminant. Maps constructed from the transport quotients provide managers with a bay-wide snapshot of areas in Tampa Bay most at risk during a hazardous bloom event., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

A coastal prediction system for Tampa Bay, comprised of a numerical circulation model and Lagrangian particle transport model, rapidly produces hindcast/forecast simulations that alert authorities to high impact areas following the introduction of hazardous material into the bay. The effectiveness of the prediction system as an event response tool is evaluated during an anhydrous ammonia spill. A week-long simulation predicts the trajectory of the material due to winds and currents. Physical transport of the model particles alternates from being tidally driven to being driven both by wind action and residual circulation. A forecast simulation showing particle distribution drove field sampling that resulted in the detection of a Pseudo-nitzschia bloom likely initiated from excess ammonium in the bay. An online component of the coastal prediction system is in development to better manage response and mitigation efforts for future hazardous material spills in Tampa Bay.