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Philip Kramer

Publications and source records attributed to Philip Kramer.

3 recordsLinked to original sources

A federal-state partnership for mapping Florida's coast and seafloor

The Florida Coastal Mapping Program, a partnership of state and federal agencies, has a goal of having modern, consistent, high- resolution sea-floor data for all of Florida’s coastal zone in the next decade to support a myriad of coastal zone science and management applications. One of the early steps in the implementation process is to prioritize and justify mapping needs. This is accomplished by holding six regional workshops across the state during which stakeholders and partners are introduced to a newly developed geospatial prioritization tool. Users independently utilize the tool to populate grid cells for a given region, and the result is a cumulative perspective on sea floor mapping priorities to inform future mapping initiatives. The tool also allows participants to indicate their primary use of sea floor mapping data and types of additional data required for their science or management need.

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Multi-site evaluation of IKONOS data for classification of tropical coral reef environments

Ten IKONOS images of different coral reef sites distributed around the world were processed to assess the potential of 4-m resolution multispectral data for coral reef habitat mapping. Complexity of reef environments, established by field observation, ranged from 3 to 15 classes of benthic habitats containing various combinations of sediments, carbonate pavement, seagrass, algae, and corals in different geomorphologic zones (forereef, lagoon, patch reef, reef flats). Processing included corrections for sea surface roughness and bathymetry, unsupervised or supervised classification, and accuracy assessment based on ground-truth data. IKONOS classification results were compared with classified Landsat 7 imagery for simple to moderate complexity of reef habitats (5-11 classes). For both sensors, overall accuracies of the classifications show a general linear trend of decreasing accuracy with increasing habitat complexity. The IKONOS sensor performed better, with a 15-20% improvement in accuracy compared to Landsat. For IKONOS, overall accuracy was 77% for 4-5 classes, 71% for 7-8 classes, 65% in 9-11 classes, and 53% for more than 13 classes. The Landsat classification accuracy was systematically lower, with an average of 56% for 5-10 classes. Within this general trend, inter-site comparisons and specificities demonstrate the benefits of different approaches. Pre-segmentation of the different geomorphologic zones and depth correction provided different advantages in different environments. Our results help guide scientists and managers in applying IKONOS-class data for coral reef mapping applications. ?? 2003 Elsevier Inc. All rights reserved.

Remote Sensing of Environment↗

The stable oxygen and carbon isotopic record from a coral growing in Florida Bay: a 160 year record of climatic and anthropogenic influence

A 160 year record of skeletal δ 13 C and δ 18 O was examined in a specimen of the coral Solenastrea bournoni growing in Florida Bay. Variations in the δ 18 O of the skeleton can be correlated to changes in salinity while changes in the δ 13 C reflect cycling of organic material within the Bay. Based on the correlation between salinity and skeletal δ 18 O, we have concluded that there has been no long term increase in salinity in this area of Florida Bay over the past 160 years. Using salinity correlations between the various basins obtained from instrumental data, we have been able to extend our interpretations to other parts of Florida Bay reaching similar conclusions. In contrast to current ideas which have focused on changes in Florida Bay water quality over the past 20-yr history of the Bay as causative in its decline, we have determined that changes in water quality in this basin were already set in motion between 1905 and 1912 by the construction of the Florida East Coast Railway from Miami to Key West. The construction of the railway resulted in the restriction of the exchange of water between the Florida reef tract and the Gulf of Mexico causing Florida Bay to become more eutrophic. Evidence of this process is observed in the sudden shift to relatively lower δ 13 C values coincident with railway construction. Natural events also appear to have influenced the water in the Bay. Between 1912 and 1948 frequent hurricanes had the effect of increasing exchange of water between the Bay and reef tract and removing large quantities of organic rich sediments. However, since 1948 the number of hurricanes affecting the area has decreased and the products of the oxidation of organic material have been increasingly retained within the basin promoting the initiation of eutrophic conditions.

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