Observing the 3-dimensional distribution of bio-optical properties of West Florida Shelf waters using gliders and autonomous platforms

The confocal laser scanning microscope has become a powerful tool in the study of the 3-dimensional distribution of proteins and specific nucleic acid sequences in cells and tissues. This is also proving to be true for a new generation of high contrast intermediate voltage electron microscopes (IVEM). Until recently, the number of labeling techniques that could be employed to allow examination of the same sample with both confocal and IVEM was rather limited. One method that can be used to take full advantage of these two technologies is fluorescence photooxidation. Specimens are labeled by a fluorescent dye and viewed with confocal microscopy followed by fluorescence photooxidation of diaminobenzidine (DAB). In this technique, a fluorescent dye is used to photooxidize DAB into an osmiophilic reaction product that can be subsequently visualized with the electron microscope. The precise reaction mechanism by which the photooxidation occurs is not known but evidence suggests that the radiationless transfer of energy from the excited-state dye molecule undergoing the phenomenon of intersystem crossing leads to the formation of reactive oxygen species such as singlet oxygen. It is this reactive oxygen that is likely crucial in the photooxidation of DAB.

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USGS field activity 09FSH02 on the west Florida shelf, Gulf of Mexico, in August 2009

Data Series ◽

10.3133/ds535c ◽

2009 ◽

Author(s):

Lisa L. Robbins ◽

Paul O. Knorr ◽

Xuewu Liu ◽

Robert H. Byrne ◽

Ellen A. Raabe

Keyword(s):

Gulf Of Mexico ◽

West Florida Shelf ◽

The West ◽

Florida Shelf ◽

Field Activity

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USGS Field Activities 11CEV01 and 11CEV02 on the West Florida Shelf, Gulf of Mexico, in January and February 2011

Data Series ◽

10.3133/ds711 ◽

2014 ◽

Author(s):

Lisa L. Robbins ◽

Paul O. Knorr ◽

Kendra L. Daly ◽

Carl A. Taylor

Keyword(s):

Gulf Of Mexico ◽

West Florida Shelf ◽

The West ◽

Florida Shelf

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High-Frequency Radar Mapping of Surface Currents Using WERA

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech1985.1 ◽

2007 ◽

Vol 24 (3) ◽

pp. 484-503 ◽

Cited By ~ 53

Author(s):

Lynn K. Shay ◽

Jorge Martinez-Pedraja ◽

Thomas M. Cook ◽

Brian K. Haus ◽

Robert H. Weisberg

Keyword(s):

Time Series ◽

High Frequency ◽

Tidal Currents ◽

Tropical Storm ◽

Surface Velocity ◽

Surface Currents ◽

West Florida Shelf ◽

The West ◽

Florida Shelf ◽

East West

Abstract A dual-station high-frequency Wellen Radar (WERA), transmitting at 16.045 MHz, was deployed along the west Florida shelf in phased array mode during the summer of 2003. A 33-day, continuous time series of radial and vector surface current fields was acquired starting on 23 August ending 25 September 2003. Over a 30-min sample interval, WERA mapped coastal ocean currents over an ≈40 km × 80 km footprint with a 1.2-km horizontal resolution. A total of 1628 snapshots of the vector surface currents was acquired, with only 70 samples (4.3%) missing from the vector time series. Comparisons to subsurface measurements from two moored acoustic Doppler current profilers revealed RMS differences of 1 to 5 cm s−1 for both radial and Cartesian current components. Regression analyses indicated slopes close to unity with small biases between surface and subsurface measurements at 4-m depth in the east–west (u) and north–south (υ) components, respectively. Vector correlation coefficients were 0.9 with complex phases of −3° and 5° at EC4 (20-m isobath) and NA2 (25-m isobath) moorings, respectively. Complex surface circulation patterns were observed that included tidal and wind-driven currents over the west Florida shelf. Tidal current amplitudes were 4 to 5 cm s−1 for the diurnal and semidiurnal constituents. Vertical structure of these tidal currents indicated that the semidiurnal components were predominantly barotropic whereas diurnal tidal currents had more of a baroclinic component. Tidal currents were removed from the observed current time series and were compared to the 10-m adjusted winds at a surface mooring. Based on these time series comparisons, regression slopes were 0.02 to 0.03 in the east–west and north–south directions, respectively. During Tropical Storm Henri’s passage on 5 September 2003, cyclonically rotating surface winds forced surface velocities of more than 35 cm s−1 as Henri made landfall north of Tampa Bay, Florida. These results suggest that the WERA measured the surface velocity well under weak to tropical storm wind conditions.

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The global 3-D distribution of tropospheric aerosols as characterized by CALIOP

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-3345-2013 ◽

2013 ◽

Vol 13 (6) ◽

pp. 3345-3361 ◽

Cited By ~ 255

Author(s):

D. M. Winker ◽

J. L. Tackett ◽

B. J. Getzewich ◽

Z. Liu ◽

M. A. Vaughan ◽

...

Keyword(s):

Lower Troposphere ◽

Aerosol Extinction ◽

Transport Pathways ◽

3 Dimensional ◽

Clear Sky ◽

Tropospheric Aerosol ◽

Vertical Distributions ◽

Dimensional Distribution ◽

Level 3 ◽

Sky Conditions

Abstract. The CALIOP lidar, carried on the CALIPSO satellite, has been acquiring global atmospheric profiles since June 2006. This dataset now offers the opportunity to characterize the global 3-D distribution of aerosol as well as seasonal and interannual variations, and confront aerosol models with observations in a way that has not been possible before. With that goal in mind, a monthly global gridded dataset of daytime and nighttime aerosol extinction profiles has been constructed, available as a Level 3 aerosol product. Averaged aerosol profiles for cloud-free and all-sky conditions are reported separately. This 6-yr dataset characterizes the global 3-dimensional distribution of tropospheric aerosol. Vertical distributions are seen to vary with season, as both source strengths and transport mechanisms vary. In most regions, clear-sky and all-sky mean aerosol profiles are found to be quite similar, implying a lack of correlation between high semi-transparent cloud and aerosol in the lower troposphere. An initial evaluation of the accuracy of the aerosol extinction profiles is presented. Detection limitations and the representivity of aerosol profiles in the upper troposphere are of particular concern. While results are preliminary, we present evidence that the monthly-mean CALIOP aerosol profiles provide quantitative characterization of elevated aerosol layers in major transport pathways. Aerosol extinction in the free troposphere in clean conditions, where the true aerosol extinction is typically 0.001 km−1 or less, is generally underestimated, however. The work described here forms an initial global 3-D aerosol climatology which we plan to extend and improve over time.

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