Douglas A. Mitchell

Common Operational Picture COP Requirements for Floating Drilling in Pack Ice

Abstract A Common Operational Picture (COP) can generally be described as a system of hardware and software that produces a shared display of information to facilitate situational awareness and dec ...

Infrared polarimetric sensing of oil on water

Infrared polarimetry is an emerging sensing modality that offers the potential for significantly enhanced contrast in situations where conventional thermal imaging falls short. Polarimetric imagery leverages the different polarization signatures that result from material differences, surface roughness quality, and geometry that are frequently different from those features that lead to thermal signatures. Imaging of the polarization in a scene can lead to enhanced understanding, particularly when materials in a scene are at thermal equilibrium. Polaris Sensor Technologies has measured the polarization signatures of oil on water in a number of different scenarios and has shown significant improvement in detection through the contrast improvement offered by polarimetry. The sensing improvement offers the promise of automated detection of oil spills and leaks for routine monitoring and accidents with the added benefit of being able to continue monitoring at night. In this paper, we describe the instrumentation, and the results of several measurement exercises in both controlled and uncontrolled conditions.

Development of Gulf of Mexico Deepwater Currents for Reference by API Recommended Practices

The metocean conditions contained in the 21st edition of API RP2A, last updated in 1993, are in the process of being revised to account for: the effects of recent major hurricanes, the shift of production to deeper water, and improvements in our understanding of metocean conditions in US waters. As the Oil Industry has moved into the deeper Gulf of Mexico waters, it has become exposed to strong currents generated by the Loop Current, its associated eddies, and by topographic Rossby waves. This paper describes the basis for the draft extreme conditions we have developed for these strong deepwater ocean currents. Further work is underway to develop conditions for extreme near-bottom currents on the continental slope and for joint hurricane-Loop currents. Once accepted by API, the conditions will ultimately be published as part of a stand-alone API recommended practice (RP) which will in turn be referenced by other API recommended practices such as those addressing shallow-water fixed platforms, jack-ups, deepwater platforms, and floating MODUs. The Metocean RP will also include hurricane-generated conditions the development of which is documented in a separate paper (Berek, et al. 2007).Copyright

New IR polarimeter for improved detection of oil on water

The Deepwater Horizon incident (April 2010, in the Gulf of Mexico) is a well-known example of a large-volume oil release (210,000,000 gallons) that had a considerable impact on the marine and coastal environment, as well as significant response costs and economic fallout. Less-well known are smaller-volume spills (typically a few gallons from natural, industrial, or recreational sources) that are regularly reported and archived by the US Environmental Protection Agency’s National Response Center. For example, 30 smaller incidents between New Orleans and Mobile Bay were reported in July 2016.1 There are various issues, however, that hamper the recovery of all oil spills. For relatively small spills, the response is heavily dependent on the ability to locate the spill—based on sporadic, and sometimes non-specific reports—and to determine its size. For larger spills, although a coordinated response team may be continually on site, recovery operations are usually limited to daylight hours. In addition, updates on the spill location are required each morning before the recovery operations can begin, which often causes hours of delay in oil recovery or mitigation. Although IR imaging may be used to detect oil spills, the thermal contrast between oil and water is often small and makes IR detection difficult. Wave action only confounds this problem. For all spills, the ability for personnel to quickly and easily detect oil on water is therefore clearly needed, so that an appropriate, consistent, and cost-effective response can be implemented. In particular, the potential to perform these functions automatically would be a great boon for oil responders. It would also provide an opportunity for regular monitoring around drilling operations and facilities, transfer points, ports, and harbors. For many years, our team at Polaris Sensor Technologies Inc. has been developing imaging polarimetric sensors that operate Figure 1. Photograph of the Pyxis R LWIR (long-wavelength IR) polarimetric sensor. In this camera, the microfilter array is mounted in close contact with the microbolometer focal plane array.

Thermal Infrared Polarimetric Sensor for Automated Detection of Oil Spills

One of the most effective ways of minimizing oil spill impact is early detection. Effective early detection requires automated detection that relies as little as possible on an operator and can ope...