X = available basically, Y = possible suitable
X = available basically, Y = possible suitable
Optical Systems of the high sanction - Optical systems of the high sanction are applicable for any platforms. For registration of the information as the digital image is using a linear photosensitive semiconductor CCD systems with quantity of elements about 12 000. Using the similar systems, adjusting them on various wavelength of spectrum it is possible of fabrication of multispectral complexes for the wide wavelength of radiation.
Presently most widely used data of the satellite, as in special as well as in commercial purposes is the IKONOS satellite. The orbit of the satellite is at height of 680 km from a terrestrial surface with width of a covering of the image about 11 00 km. Operation of this system basically is the within the visible spectral range that limits the implementation of monitoring when the condition of weather is not applicable for receiving the information. The fact is the work of IKONOS depends on the condition of atmosphere.
Hyperspectral Sensors - Hyperspectral sensors measure a degree of reflection of natural and artificial objects with the high spectral resolution which allow to identify different items existing on the surface of the ground. They are huge elements on the surface of the ground (pigments of vegetation, minerals, rock, artificial surfaces) give the different spectra of absorption. It allows carrying out the analysis and identification of images on the basis of the collected information.
Display SAR (Synthetic Radar of the Aperture) Systems - SAR systems provide the holographic image of the local place, scanned by radar. Selecting the appropriate frequencies of spectral lengths is possible to achieve the spectral area which is transparent for the atmosphere. In this case atmospheric influences may not become a handicap for carrying out a permanent monitoring the earth a surface and detection of images. Change of resolution SAR demands of changing of the aperture and aerials of this system that limits its wide application.
Interferometric SAR - Interferometric SAR uses the phase information contained in the radar waves of two or more SAR images to develop terrain models and detect ground surface movements in the centimeter range. With tandem operation of identical SAR satellites such as the combined flights of the European ERS-1 and ERS-2 and the planned operations of Radarsat II and Radarsat III, images of the same area can be recorded with very short intervals of one day (ERS) or even only a few minutes (planned by Radarsat). As regards pipeline monitoring, this method could conceivably be in use of detecting subsidence following water abstraction and the collapse of subterranean hollows or for monitoring slopes subject to slippage.
Investigation of the petroleum hydrocarbons on a plot and its analysis is advisable to conduct before and after the oil spill, to characterize changes in vegetative condition through time. Figure 4 shows an example of the oil spill accident occurred due to the third party intervention.
This area was used for further investigations as a spilled area indicated for a long term ecological monitoring site (David Reister et al., partnership programme).
An implementation of these studies started from the collection of remotely sensed data from ground, airborne and satellite and the results of all information were combined.
Oil spill site has a plant canopy dominated by creosote bush (Larrea tridentata) shrub land. Qualitative field investigations indicated that upper plant canopy contact with the diesel fuel was manifest as etiolation that resulted in a grey to white color of the upper canopy and a white to slight reddening of the lower canopy graminoids and litter, partial and complete defoliation of shrubs, apparent high mortality of much of the above ground phytomass, including grasses, cactiods and biological crusts and darkening of the orange-red alluvial soil. It was an evident that the spill boundary could be delineated on the bases of smell, as diesel was still volatizing from the soil. These features were still valuable evident one year after the release. It is necessary to note that the canopy dominant, creosote bush is expected to recover from the diesel spill. This aspect of plant physiology is significant for studies of resilience in desert ecosystems.
Following application of the oil, vegetation damage was assessed visually via changes in leaf color and leaf fall. It showed three main time frames for injuries:
• occurring during the initial growing season and
• cumulative, occurring after the initial growing season
Virtually all aboveground foliage that came into contact with the oil was quickly cleaned up. Turgidity was immediately reduced and foliage appeared dead within several days. The zone of contact was generally limited to the immediate areas and to areas of low relief in the pass of aboveground flowing oil (Jenkins et al., Arctic, 1978).
In contrast, cottongrass tussock with a raised, upright growth form and species growing on areas of higher relief kept most of their aboveground biomass above the oil. These species continued to grow and flower despite their being surrounded by oil (Fig. 5).
The features of vegetation and natural growth as physical and biological parameters depends of the oil spill interaction can be used a key instrument of spectral behaviors of information within the data processing of space images for linear infrastructures.
Remote Sensing Technology of Relevance to the Oil Spill Treaty
Oil Spill Monitoring - The Bonn Agreement, officially known as The Agreement for Cooperation in Dealing with Pollution of the North Sea by Oil and Other Harmful Substance (1983) is an example of a rigorously enforced agreement within the context of the International Convention for the Prevention of Pollution from Ships (MARPOL). Under the Bonn Agreement, monitoring procedures were set up to track oil spills to the ships of origin. Because oil slicks change the surface roughness of water bodies under the windy condition that generally prevail on high seas and this registers as changes in backscatter on radar instruments, SAR images proved to be useful for spill monitoring. However, radar images generally give an unacceptable number of false positives, so the technology is only applicable as a surveillance tool in conjunction with infrared and ultraviolet sensors, used for reconnaissance and confirmation of potential slicks. Under the Bonn Agreement, photographic evidence is still required in order to bring a ship's owner to prosecution.
From 2002, the International Maritime Organization is required vessel tracking transponders on all commercial ships; this permits back-tracking of vessels to the scene of an oil slick several hours after the initial incident occurred. However, the potential for a fully automated system is some ways off (Alex de Sherbinin and Ch. Giri Rio de Janeiro, and October 2001). Opportunely and fast note in their own treatment of the subject that the legal systems in most countries still require the testimony of a person such as a coastguard officer, in addition to remote sensing images and photographs.
Advances in information systems, satellites imaging systems and improvement software technologies and consequently data processing led to opportunities for a new level of information products from remote sensing data. The integration of these new products into existing response systems can provide a huge range of analysis tools and information products that were not possible in the past. For instance, with the higher resolution of the space imagery and change detection of the linear infrastructure situational awareness and damage and assessment by impact of the variety of reasons can be implemented rapidly and accurately. All this presented information sources can be valuable in the response, recovery and rehabilitation phases of the preparedness management issue.
The lack of periodically observation data for satisfaction needs in oil and gas spills is the main obstacle for the mentioned problem. In this regard satellite data can be playing a significant place. For more success in this sphere spatial and non spatial data would be integrated with the geographic information system. This system has to be integrated for the regional scale covering the whole regions state around the Caspian Sea.
The presented above results show a sensitivity of parameters of various vegetations to the influences of oil pollution. Such behavior opens an opportunity of use of those behaviors of vegetations for monitoring of the linear infrastructures as environmental indicators. These indicators significantly could be in use as a key instrument within the data processing and interpretation of space images for safety and security issues of the transportations of oil and gas pipeline infrastructure.
At the time available technologies for successful implementation of issues related to the pipeline safety were discussed. Depends of the existed huge of problems and tasks appropriate technology as well as system can be applied and carried out for these purposes.
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