High Resolution Ocean Radar Observations in Ports and Harbours

Observations are shown from an ocean radar system which operates in the VHF frequency band (100-180 MHz) and produce surface current measurements on grid scales of 50-200m over ranges up to 6-10 km. This is a scale of operation that is well suited to measurement tasks in Ports, harbours and coastal zones. Ocean radars commonly used for mapping surface currents in coastal zones operate in the HF frequency band and measure currents on grid scales of 3-6 km over distances of 100-200km. The VHF ocean radar system consists of two stations which look at the same patch of ocean from different directions. Each station measures the radial component of the surface current at each grid point, and by combining data from both stations it is possible to produce maps of surface current vectors. Each station can cover a 60-degree sector of azimuth, and for wider coverage it is possible to use multiplexed receive antennas to double the size of the sector. The time to make the basic 60-degree sector for two stations is 10 minutes, and becomes 20 minutes for the wider 120 degree coverage. Results are shown for sheltered coastal waters and for open coast line where there are breaking waves. This methodology is particularly appropriate for monitoring currents in congested port areas where fixed moorings may be compromised

Upwelling linked to warm summers and bleaching on the Great Barrier Reef

We investigate a range of indices to quantify upwelling on the central Great Barrier Reef (GBR), Australia, so that environmental and biological relationships associated with upwelling in this area can be explored. We show that "Upwelling days" (the number of days of upwelling) and diurnal variation in subsurface temperature (maximum-minimum, 20-m depth) are satisfactory metrics to describe the duration and intensity of upwelling events, respectively. We use these to examine key characteristics of shelf-break upwelling in the central GBR. Our results show, somewhat paradoxically, that although upwelling involves cold water being brought near to the surface, it is linked to positive thermal anomalies on the GBR, both locally and regionally. Summers (December to February) with strongest upwelling occurred during the GBR-wide bleaching events of 1997-1998 and 2001-2002. Upwelling in the GBR is enhanced during doldrums conditions that were a feature of these summers. During these conditions, the poleward-flowing East Australian Current flows faster, lifting the thermocline closer to the surface, spilling more sub-thermocline waters onto the shelf. Doldrums conditions also result in intense local heating, stratification of the water column, and, when severe, coral bleaching. Upwelling intrusions are spatially restricted (central GBR), generally remain subsurface, and are often intermittent, allowing GBR-wide bleaching to occur despite conditions resulting in enhanced upwelling. Intense upwelling events precede anomalous seasonal temperature maxima by up to 2 months and bleaching by 1-3 wk, leading to the prospect of using upwelling activity as a seasonal forecasting index of unusually warm summers and widespread bleaching

The ethics of intimate student-faculty relationships

What are the ethics behind intimate student-faculty relationships in higher education? Should such relationships be allowed? Can they be legally controlled? Should there be a penalty for faculty and students who engage in these relationships? Consenting romantic and/or sexual relationships between faculty and student, or between student services professional and student, although usually not expressly forbidden, are generally deemed unwise (Cahn, 1986). According to Svinicki (1994), codes of ethics for most professional associations forbid professional-client sexual relationships. In an educational institution, the professor-student and student affairs professional-student relationships are thus such professional-client relationships. The respect and trust accorded a professor by a student, as well as the power exercised by the professor over the student in giving praise or blame, grades, recommendations for further study or future employment, etc., can greatly diminish the student\u27s actual freedom of choice in such relationships (Svinicki, 1994). Consequently, it is incumbent upon those with authority to make certain students not be exploited

Do Clouds Save the Great Barrier Reef? Satellite Imagery Elucidates the Cloud-SST Relationship at the Local Scale

Evidence of global climate change and rising sea surface temperatures (SSTs) is now well documented in the scientific literature. With corals already living close to their thermal maxima, increases in SSTs are of great concern for the survival of coral reefs. Cloud feedback processes may have the potential to constrain SSTs, serving to enforce an “ocean thermostat” and promoting the survival of coral reefs. In this study, it was hypothesized that cloud cover can affect summer SSTs in the tropics. Detailed direct and lagged relationships between cloud cover and SST across the central Great Barrier Reef (GBR) shelf were investigated using data from satellite imagery and in situ temperature and light loggers during two relatively hot summers (2005 and 2006) and two relatively cool summers (2007 and 2008). Across all study summers and shelf positions, SSTs exhibited distinct drops during periods of high cloud cover, and conversely, SST increases during periods of low cloud cover, with a three-day temporal lag between a change in cloud cover and a subsequent change in SST. Cloud cover alone was responsible for up to 32.1% of the variation in SSTs three days later. The relationship was strongest in both El Niño (2005) and La Niña (2008) study summers and at the inner-shelf position in those summers. SST effects on subsequent cloud cover were weaker and more variable among study summers, with rising SSTs explaining up to 21.6% of the increase in cloud cover three days later. This work quantifies the often observed cloud cooling effect on coral reefs. It highlights the importance of incorporating local-scale processes into bleaching forecasting models, and encourages the use of remote sensing imagery to value-add to coral bleaching field studies and to more accurately predict risks to coral reefs

Human System Drivers for Exploration Missions

Evaluation of DRM4 in terms of the human system includes the ability to meet NASA standards, the inclusion of the human system in the design trade space, preparation for future missions and consideration of a robotic precursor mission. Ensuring both the safety and the performance capability of the human system depends upon satisfying NASA Space Flight Human System Standards.1 These standards in turn drive the development of program-specific requirements for Near-earth Object (NEO) missions. In evaluating DRM4 in terms of these human system standards, the currently existing risk models, technologies and biological countermeasures were used. A summary of this evaluation is provided below in a structure that supports a mission architecture planning activities. 1. Unacceptable Level of Risk The duration of the DRM4 mission leads to an unacceptable level of risk for two aspects of human system health: A. The permissible exposure limit for space flight radiation exposure (a human system standard) would be exceeded by DRM4. B. The risk of visual alterations and abnormally high intracranial pressure would be too high.

Human Health and Performance Considerations for Exploration of Near-Earth Asteroids (NEA)

This poster paper reviews the Astronaut health and performance issues for a Near Earth Asteroid (NEA) mission. Risks and other considerations are grouped into four categories and they are characterized for criticality

Evaluation of a new airborne microwave remote sensing radiometer by measuring the salinity gradients across the shelf of the Great Barrier Reef lagoon

Over the last ten years, some operational airborne remote sensing systems have become available for mapping surface salinity over large areas in near real time. A new dual-polarized Polarimetric L-band Multibeam Radiometer (PLMR) has been developed to improve accuracy and precision when compared with previous instrument generations. This paper reports on the first field evaluation of the performance of the PLMR by measuring salinity gradients in the central Great Barrier Reef. Before calibration, the raw salinity values of the PLMR and conductivity-temperature-depth (CTD) differed by 3-6 psu. The calibration, which uses in situ salinity data to remove long-term drifts in the PLMR as well as environmental effects such as surface roughness and radiation from the sky and atmosphere, was carried out by equating the means of the PLMR and CTD salinity data over a subsection of the transect, after which 85% of the salinity values between the PLMR and CTD are within 0.1 psu along the complete transect. From offshore to inshore across the shelf, the PLMR shows an average cross-shelf salinity increase of about 0.4 psu and a decrease of 2 psu over the inshore 20 km at -19deg S (around Townsville) and -18deg S (around Lucinda), respectively. The average cross-shelf salinity increase was 0.3 psu for the offshore 100 km over all transects. These results are consistent with the in situ CTD results. This survey shows that PLMR provided an effective method of rapidly measuring the surface salinity in near real time when a calibration could be made

Evaluation of ADCP wave, WAVEWATCH III and HF radar data on the GBR

Wave climate can have a very significant impact on the dynamics of the near-coastal oceans, including geomorphology and currents. This study is a preliminary investigation of the suitability and compatibility of a wave-capable Acoustic Doppler Current Profiler (ADCP) mooring, an HF ocean radar system and the numerical model WAVEWATCH III (WW3), with the focus on the area of the Capricorn and Bunker Groups of reefs and islands, Australia

Decompression Sickness: Case Study of Identification of Knowledge and Disposition Gaps Using Principles of Continuous Risk Management

No abstract availabl

Why Should Humans Explore a Near Earth Asteroid and What Factors Drive the Medical Risks?

The National Aeronautics and Space Administration (NASA) is currently considering plans for the human exploration of a Near Earth Asteroid (NEA). Reasons for undertaking the human exploration of a NEA include increasing the scientific understanding of the origins of our solar system, and developing technology for the exploration of more distant destinations such as Mars. Most mission scenarios have a duration on the order of several months or a year, most of which is spent in transit to and from the NEA. The choice of a particular NEA destination determines the mission duration and guides the types of exploration activities that can be performed on and near the NEA. NASA s Human Research Program (HRP) has identified short and long-term health risks associated with such missions and begun characterizing the level of risk. Some risk drivers are well known from missions to low Earth orbit and the Moon (e.g., the limited mass, volume, and power available for the medical care system). Other factors emerge as major drivers for NEA missions. Some are fundamental characteristics of the mission parameters (e.g., mission duration, distance) and others are strongly dependent on the specifics of how the mission is implemented (e.g., isolation and confinement). Careful consideration of these factors will be required for safe and effective missions to NEAs