Digital Commons Network^™

Data Summary From The Tampa Bay Interagency Seagrass Monitoring Program Through The Year 2001, Roger Johansson, Walt Avery

Reports

This paper presents a general overview of the Tampa Bay Interagency Seagrass Monitoring Program and results concerning seagrass distribution within Tampa Bay. Further, a summary of trends in areal coverage and major changes in species composition observed during the course of the monitoring program are also included. Data collected during the course of the program pertaining to water quality, sediment composition, and epiphytes are not discussed within this report. All inf

Seismotectonics Of The Explorer Region, Jochen Braunmiller, John Nábělek

School of Geosciences Faculty and Staff Publications

The Explorer region offshore western Canada is a tectonically complex area surrounded by the Pacific, North America, and Juan de Fuca plates. Existing tectonic models for the region differ fundamentally. Proposed plate configurations range from multiple independent plate fragments to an Explorer plate now fused to North America along the continental margin and cut by Pacific–North America transform faults in the west. We present new seismological data constraining the region's current tectonics. We use three-component regional waveforms to determine the source parameters of 84 earthquakes with magnitude greater than 4. Combined with 34 Harvard centroid moment tensor solutions, they represent …

Seismic Cycle And Rheological Effects On Estimation Of Present-Day Slip Rates For The Agua Blanca And San Miguel-Vallecitos Faults, Northern Baja California, Mexico, Timothy H. Dixon, J. Decaix, F. Farina, K. Furlong, Rocco Malservisi

School of Geosciences Faculty and Staff Publications

Geodesy can be used to infer long‐term fault slip rates, assuming a model for crust and upper mantle rheology. We examine the sensitivity of fault slip rate estimates to assumed rheology for the Agua Blanca and San Miguel‐Vallecitos faults in northern Baja California, Mexico, part of the Pacific–North America plate boundary zone. The Agua Blanca fault is seismically quiet, but offset alluvial fans indicate young activity. Current seismicity is confined to the nearby San Miguel‐Vallecitos fault, a small offset fault better aligned with plate motion. GPS measurements between 1993 and 1998 suggest that both faults are active, with a combined …

Satellite Imagery Proves Essential For Monitoring Erupting Aleutian Volcano, Kenneson Dean, Jonathan Dehn, Stephen R. Mcnutt, Christina Neal, Richard Moore, Dave Schneider

School of Geosciences Faculty and Staff Publications

Mt. Cleveland is one of more than 40 active volcanoes in Alaska that is monitored by the Alaska Volcano Observatory (AVO). It is located on the western half of Chuginadak, a remote and uninhabited island in the east central Aleutians that lies 1526 km southwest of Anchorage. The closest inhabited community, Nikolski, is 75 km to the east on Umnak Island (Figure 1). Mt. Cleveland erupted explosively on 19 February and on 11 and 19 March 2001. Because the volcano is not yet monitored with seismic, deformation, or other geophysical instruments, satellite imagery was the only effective tool for detecting …

Seagrass And Caulerpa Monitoring In Hillsborough Bay Thirteenth Annual Report, City Of Tampa Department Of Sanitary Sewers

Reports

This is the thirteenth annual report to FDER to satisfy the requirements set forth in Reclaimed Water and Effluent Limitations and Monitoring Requirements condition #10 of the Howard F. Curren WWTP operation permit FL0020940-001-DW1P.

The City of Tampa, Bay Study Group (BSG), has monitored the effects of sewage pollution abatement in Hillsborough Bay since 1976. During the mid 1980's, water quality improvements and evidence of minor seagrass revegetation in Hillsborough Bay prompted the BSG to initiate a seagrass study to compliment other programs assessing the environmental status of Hillsborough Bay.

Results Of The City Of Tampa Surface Water Compliance Monitoring Program For The Year 2001 And Examination Of Long-Term Water Quality And Biological Indicator Trends In Hillsborough Bay, City Of Tampa Department Of Sanitary Sewers

Reports

This report is submitted to Florida Department of Environmental Regulation (FDER) to satisfy the requirements set forth in specific condition No. 10 of Howard F. Curren WWTP permit FL0020940-001-DW1P. The report is based on data obtained by the City of Tampa (COT) surface water compliance monitoring program approved on August 14, 2000 by the FDEP. The report also includes examination of long-term trends for water quality parameters and biological indicators collected by the City of Tampa Bay Study Group and the Environmental Protection Commission of Hillsborough County (EPC).

Revel: A Model For Recent Plate Velocities From Space Geodesy, Giovanni F. Sella, Timothy H. Dixon, Ailin Mao

School of Geosciences Faculty and Staff Publications

We present a new global model for Recent plate velocities, REVEL, describing the relative velocities of 19 plates and continental blocks. The model is derived from publicly available space geodetic (primarily GPS) data for the period 1993–2000. We include an independent and rigorous estimate for GPS velocity uncertainties to assess plate rigidity and propagate these uncertainties to the velocity estimates. The velocity fields for North America, Eurasia, and Antarctica clearly show the effects of glacial isostatic adjustment, and Australia appears to depart from rigid plate behavior in a manner consistent with the mapped intraplate stress field. Two thirds of tested …

Consistency Of Geologic And Geodetic Displacements During Andean Orogenesis, David Hindle, Jonas Kley, Eryn Klosko, Seth Klosko, Timothy H. Dixon, Edmundo Norabuena

School of Geosciences Faculty and Staff Publications

Present-day displacements within the Central Andes are being measured using high precision GPS geodesy. Until now, comparison of such ground motions within deforming plate boundary zones to those on a geologic time scale has not been possible due to lack of sufficient geological data. In the Central Andes, a comparable dataset for the past 25 Ma of mountain building can be reconstructed. Here, we use new interpretations of shortening rates averaged over 25–10 Ma and 10 Ma–present and find that whilst displacement directions have remained virtually constant and parallel, an acceleration has occurred synchronously with a slowing of convergence between …

Longshore Sand Transport – Initial Results From The Large-Scale Sediment Transport Facility, Ping Wang, Bruce A. Ebersole, Ernest R. Smith

Geology Faculty Publications

Accurate predictions of the total rate of longshore sand transport (LST) and its cross-shore distribution pattern in the surf zone are central to many coastal engineering studies. Present understanding and methods for calculating the LST rate are largely developed based on field studies (e.g., Komar and Inman 1970; Inman et al. 1981; Kraus et al. 1982; Bodge and Dean 1987a, b; Dean 1989; Schoonees and Theron 1993; Miller 1998; Wang, Kraus, and Davis 1998; Wang 1998; Wang and Kraus 1999; Miller 1999). The Coastal Engineering Research Center (CERC) formula (Shore Protection Manual 1984), which is based on field measurements, is …

Surface Water Quality - 2001 Hillsborough County, Florida Raw Data Summary, Tom Cardinale

Reports

The Environmental Protection Commission of Hillsborough County (EPC) is charged with the responsibility of monitoring the quality of surface water in the county. The data and information collected enables staff to determine pollution status and trends throughout Tampa Bay and it's tributaries. The data is also widely distributed to other government agencies, academia, the local scientific community and the general public. EPC's routine monthly surface water monitoring began in January of 1972, with the Tampa Bay estuary and was expanded to maj or rivers and streams in 1973. This report is a tabulation of the raw data produced on surface …

2002 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 2002.

Historical And Current Observations On Macroalgae In The Hillsborough Bay Estuary, J.O.R. Johansson

Reports

To improve the understanding of macroalgae dynamics it was recommended that long-term monitoring of the macroalgae in the bay be initiated. Subsequently, the City of Tampa initiated a Hillsborough Bay macroalgae monitoring program that since 1986 has been providing consistent monthly biomass and species composition information from five fixed transects. In addition to the transect monitoring, low level aerial observations are conducted on a near monthly schedule for estimations of bay-wide macroalgae and seagrass coverage. Results indicate that the annual bay-wide macroalgae coverage has decreased near steadily from about 300ha in the late 1980's to less than 30ha since 1997.

Understanding The Role Of Macroalgae In Shallow Estuaries, Maryland Department Of Natural Resources

Reports

No abstract provided.

Historical Overview Of Tampa Bay Water Quality And Seagrass Issues And Trends, J.O. R. Johansson

Reports

Historical (pre-1930s) seagrass meadows in Tampa Bay are believed to have covered 31,000 ha of the shallow bay bottom. Later, impacts to the bay from increasing population and industrial development of the Tampa Bay area have resulted in large seagrass losses. By 1982, approximately 8,800 ha of seagrass remained. Since 1982, Tampa Bay seagrass monitoring programs have recorded a reversal in the trend of seagrass loss, with the baywide seagrass cover increasing from 9,420 ha in 1988 to 10,890 ha in 1997. However, between 1997 and 1999 the trend again reversed with substantial losses recorded, specifically in the Old Tampa …

2002 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 2002.