Changes In Submersed Macrophytes In Relation To Tidal Storm Surges

We analyzed long-term submersed macrophyte presence-absence data collected from 15 stations in Kings Bay/Crystal River, Florida in relation to three major storm events. The percent occurrence of most species declined immediately after storm events but the recovery pattern after the storm differed among species. Hydrilla (Hydrilla verticillata (L.F.) Royle)and Eurasian watermilfoil (Myriophyllum spicatum L.) exhibited differing recolonization behaviors. Eurasian watermilfoil recolonized quickly after storms but declined in abundance as hydrilla began to increase in abundance. Natural catastrophic events restructure submersed macrophyte communities by eliminating the dominate species, and allowing revegetation and restructuring of communities. Tidal surges may also act to maintain species diversity in the system. In addition, catastrophic events remove dense nuisance plant growth for several years, altering the public's perception of the nuisance plant problem of Kings Bay/Crystal River.

Changes In Submersed Macrophytes In Relation To Tidal Storm Surges

We analyzed long-term submersed macrophyte presence-absence data collected from 15 stations in Kings Bay/Crystal River, Florida in relation to three major storm events. The percent occurrence of most species declined immediately after storm events but the recovery pattern after the storm differed among species. Hydrilla (Hydrilla verticillata (L.F.) Royle)and Eurasian watermilfoil (Myriophyllum spicatum L.) exhibited differing recolonization behaviors. Eurasian watermilfoil recolonized quickly after storms but declined in abundance as hydrilla began to increase in abundance. Natural catastrophic events restructure submersed macrophyte communities by eliminating the dominate species, and allowing revegetation and restructuring of communities. Tidal surges may also act to maintain species diversity in the system. In addition, catastrophic events remove dense nuisance plant growth for several years, altering the public's perception of the nuisance plant problem of Kings Bay/Crystal River.

Some effects of tropical storm Agnes on water quality in the Patuxent River estuary

A post Agnes study emphasizing environmental factors...weekly sampling at eight stations from 28 June to August 30, 1972. Spatial and temporal changes in the distribution of many factors, e.g., salinity, dissolved oxygen (DO), seston, particulate carbon and nitrogen, inorganic and organic fractions of dissolved nitrogen and phosphorus, and chlorophyll a were studied and compared to earlier extensive records. Patterns shown by the present data were compared especially with a local heavy storm that occurred in the Patuxent drainage basin during July 1963. Some interesting correlations were observed in the data. (PDF has 39 pages.)

Assessing societal vulnerability of U.S. Pacific Northwest communities to storm induced coastal change

Progressive increases in storm intensities and extreme wave heights have been documented along the U.S. West Coast. Paired with global sea level rise and the potential for an increase in El Niño occurrences, these trends have substantial implications for the vulnerability of coastal communities to natural coastal hazards. Community vulnerability to hazards is characterized by the exposure, sensitivity, and adaptive capacity of human-environmental systems that influence potential impacts. To demonstrate how societal vulnerability to coastal hazards varies with both physical and social factors, we compared community exposure and sensitivity to storm-induced coastal change scenarios in Tillamook (Oregon) and Pacific (Washington) Counties. While both are backed by low-lying coastal dunes, communities in these two counties have experienced different shoreline change histories and have chosen to use the adjacent land in different ways. Therefore, community vulnerability varies significantly between the two counties. Identifying the reasons for this variability can help land-use managers make decisions to increase community resilience and reduce vulnerability in spite of a changing climate. (PDF contains 4 pages)

Investigating changes in global tropical cyclone storm frequency and intensity

Understanding fluctuations in tropical cyclone activity along United States shores and abroad becomes increasingly important as coastal managers and planners seek to save lives, mitigate damage, and plan for resilience in the face of changing storminess and sea-level rise. Tropical cyclone activity has long been of concern to coastal areas as they bring strong winds, heavy rains, and high seas. Given projections of a warming climate, current estimates suggest that not only will tropical cyclones increase in frequency, but also in intensity (maximum sustained winds and minimum central pressures). An understanding of what has happened historically is an important step in identifying potential future changes in tropical cyclone frequency and intensity. The ability to detect such changes depends on a consistent and reliable global tropical cyclone dataset. Until recently no central repository for historical tropical cyclone data existed. To fill this need, the International Best Track Archive for Climate Stewardship (IBTrACS) dataset was developed to collect all known global historical tropical cyclone data into a single source for dissemination. With this dataset, a global examination of changes in tropical cyclone frequency and intensity can be performed. Caveats apply to any historical tropical cyclone analysis however, as the data contributed to the IBTrACS archive from various tropical cyclone warning centers is still replete with biases that may stem from operational changes, inhomogeneous monitoring programs, and time discontinuities. A detailed discussion of the difficulties in detecting trends using tropical cyclone data can be found in Landsea et al. 2006. The following sections use the IBTrACS dataset to show the global spatial variability of tropical cyclone frequency and intensity. Analyses will show where the strongest storms typically occur, the regions with the highest number of tropical cyclones per decade, and the locations of highest average maximum wind speeds. (PDF contains 3 pages)

Mastigophora and Rhizopoda found in saline lakes Weissovo and Repnoie (near Slaviansk). Selected passages describing Ochromonas species and Pedinella. [Translation of: Trudy Obshch.Ispyt.Prir.imp.khar'kov.Univ. 21 119-140, 1888]

This translation includes selected passages of a longer paper on Mastigophora and Rhizopoda found in saline lakes Weissovo and Repnoie. The translation focuses on describing taxonomy and morphology of Ochromonas species and Pedinella. Plates and figures of the original paper are not included in the translation.

Tropical and subtropical moisture and southerly displaced North Pacific storm track: factors in the growth of late Quaternary lakes in the Mojave Desert

Historical flood events produced lakes in the Mojave River watershed in southeastern California and represent climatic conditions similar to those in the late Quaternary when perennial lakes formed in the Mojave Desert. Historical lakes are related to tropical and subtropical sources of moisture and an extreme southward shift of storm tracks. It is suggested that this atmospheric pattern occurred frequently during earlier periods with perennial lakes in the Mojave River drainage basin.