Projects

NORTH CASPIAN SEA OIL SPILLS RADAR SATELLITE MONITORING

In 2007, ScanEx RDC together with NGO Transparent World launched the on-line project, aimed at the monitoring of oil spills in the Caspian Sea. The project’s goal is to collect operational and unbiased data on the Northern Caspian Sea water area pollution by oil and oil products and to provide this data to a wide range of users via an open Internet-resource.

Monitoring is based on all-weather near real-time radar imaging from Envisat and Radarsat satellites, arranged by ScanEx RDC. For this purpose different imaging modes is applied, including the wide field imaging mode, covering the water area of 300 to 500 km in swath width and 50 to 150 m of resolution.

Oil Spills Monitoring Background

It goes almost without saying today that the modern space radar imagery is the most efficient way to resolve the task of sea oil spills monitoring thanks to being an all-weather and round-the-clock tool of delivering high resolution wide field images. The oil spilled to the sea surface forms an oil spot, which film damps small wind-waves and creates smoothed areas, called slicks. Those slicks are depicted in dark color on a radar image. However, there is a number of natural factors that limit the radar imagery application in the resolution of such kind of tasks. Thus, for example, in low wind of 1-2 m\sec the oil films can not be discriminated on the background of dark (smoothed) sea surface, whereas in strong wind of 10-12 m\sec they disappear due to intensive wave action. The wind speed of 3 to 8 m\sec is ideal for the correct oil spill detection: in this case oil slicks look as dark spots on the bright wave-covered water surface.

Pure oil (crude oil) is rare. Most spills are formed as a result of an oil tanker cracking or an oil platform problem. Oil products or surfactants (synthetic surfactants) are the most common reasons for the creation of oil slicks of man-made origin. These products get into the sea in most different ways: with river runoff, with ship wastes, with sewage water.

A separate issue is the oil seeping from natural mud springs on the sea bottom – it forms thin oil films that, generally speaking, are not man-made pollutions. Nonetheless, they contribute to the total level of pollution, especially on the south-western part of the Caspian Sea (see Publications section).

In addition, slicks and slick formations can be formed not only by oil, oil products and surfactants but by different processes in the upper sea layer and in surface layer. Similar surface effects on radar images may be caused by calm sea conditions, upwelling, rain cells, internal waves in the ocean and in the air, biogenic surfactants, phytoplankton blooming, etc. Such phenomena should be excluded from studying based on additional data about the wind, sea state, and surface temperature and chlorophyll concentrations, available in the Internet.

And finally, oil spills differ from other slicks by a typical form, size, contrast, orientation with regard to the dominant wind and streams, position with respect to man-made objects (platforms, ships, and terminals).

Project Summary

In this project oil spills identification is done based on the expert review using the developed classification system. After detection, oil spills data are loaded onto the Internet-site of the project.

A geo-information approach is applied to get a better understanding of the oil sources and to perform a comprehensive analysis of radar data used in the project as the main information source of sea oil pollutions. Main ideas of the geoinformation approach to the sea oil slicks mapping problem are stated in a series of scientific releases. It is based on the integration of different cartographic, geographic and geophysics data as well as of RS data into GIS. On-line GIS version contains data, helping an expert to identify and classify oil slicks, detected on radar images, such as: sea basin properties data (seashore, bathymetry, coastline hydrography, etc.), navigation data (sea routes, ports, terminals, etc.), oil and gas production fields, oil bearing structures and fuel and energy complex infrastructures (wells, pipelines, drilling rigs, oil-loading platforms, etc.)

A variety of input data was used to create GIS: geographic databases, navigation maps, remote sensing data, etc. General vector layers, with the coastline verified by Landsat-7 2006-2007 images, developed in NGO Transparent World, were used as GIS foundation. Navigation maps (Headquarters of Navigation and Oceanography of the RF Defense Ministry) were the principle source of data about bathymetry and navigation objects in the northern part of the Caspian Sea. Certain data, such as navigation routes, was verified based on radar images. “Geobyte” company kindly presented vector layers of the fuel and energy complex infrastructure and oil bearing areas of the northern part of the Caspian Sea from Electronic Information System “Oil and Gas Reservoirs in Russia”. Vector data about the boundaries of the valuable natural areas (strict nature reserves, protected sanctuaries, ornithological reserves) is presented by “Gis-Lab” group or created together with NGO Transparent World.

As a result, the user may interactively view radar images analysis results in GIS by activating/deactivating additional information layers for the monitoring area, have a look at descriptions and properties of each pollution, and visualize a fragment of a radar image.

It is envisaged that generalized monitoring results will be presented as summary multi-temporal maps of sea oil spills distribution and of hazardous areas detection. The maps will be placed into the “Results” section of the project.

The project is run for the account of project arrangers. Project participants reserve the right to present independent and unbiased viewpoint on the Caspian Sea pollution issue.

NGO Transparent World hopes that the availability of independent impartial information on the cases of water area contamination with hydrocarbons will cause oil production companies to an earlier emergency response and governmental agencies – to carry out efficient monitoring and to build a sound ecological policy.

Project Coordinators

Project is managed by NGO Transparent World (www.transparentworld.ru) partnered with Russian organizations:

• ScanEx Research & Development Center (www.scanex.com)
• P.Shirshov Institute of Oceanology of the Russian Academy of Sciences (www.ocean.ru)
• ООО «Geobyte» (www.geobyte.ru)
• «Gis-Lab» (www.gis-lab.info)

Idea: О. Gershenzon (olga@scanex.ru)

Scientific advisor: А. Ivanov (ivanoff@ocean.ru)

Coordinators from ScanEx RDC: М. Zimin (zimin@scanex.ru), V. Zatyagalova (vzatyagalova@scanex.ru)

Coordinator from NGO Transparent World: D. Aksenev (picea@online.ru )

Project design: D. Aksenev, A. Kostikova, A. Matveev, Yu. Zenkevich

Project web-site: http://maps.transparentworld.ru/caspian

Classification of Oil Spills in the Project:

1. river runoff (films of oil products, natural and synthetic surfactants, getting into the sea along with sewage water (synthetic detergents), industrial wastes (ore flotation benefication, chemical products separation, polymers production, oil and gas wells drilling technique improvement, equipment corrosion protection, textile, oil and chemical industry), as well as along with agricultural wastewater (emulsifiers in pesticides, insecticides, fungicides, herbicides and defoliants);
2. vessel oil leaks : 1) ballast water, used to fill in the tanks of the oil ships, and tank flush water (oil and oil-products mixed with water); 2) engine wastes – motor oil and lubricants, used to grease ship mechanisms, and 3) bilge water, accumulated on the vessel bottom in most cases containing oil products and lubricants;
3. possible vessel oil leaks (in cases, when the vessel lick is evident, but is not related to a specific vessel, ship track, anchorage, roadstead, etc., i.e. identified at 50% probability);
4. oil pollution (oil and oil products pollution as a result of leaks during prospecting drilling, oil production and transportation, abandoned wells leaks, sunk vessels, mud springs on the sea bottom, etc., as well as accidental discharge from oil storage tanks, terminals, oil refineries and other fuel and energy complex facilities);
5. possible oil pollution (including in case when the oil spill has a typical structure and contrasts, but not directly related to any of the fuel and energy complex facilities, i.e. identified at 50% probability).

Finally, oil spills having size and forms, typical for oil pollution, but of other biogenic or anthropogenic origin, will be classified as accumulations of natural or synthetic surfactants.

Reference index:

1. A.Ivanov, S. Vostokov, I. Ermoshkin, Mapping of Oil Slicks Polluting Sea Surface Based on Space Radar Data (the Caspian Sea) // Earth Exploration from Space, 2004, № 4, p.82-92. (http://www.scanex.ru/en/publications/pdf/publication13.pdf)
2. A. Ivanov, I. Ermoshkin, M. Fang, Use of the Wide-Swath Synthetic Aperture Radar Images for Mapping Sea Oil Pollution // Earth Exploration from Space, 2005, № 5, p.78-95. ( http://www.scanex.ru/en/publications/pdf/publication12.pdf )
3. V. Zatyagalova, A. Ivanov, A GIS Approach to Mapping Oil Spills in the Marine Environment// http://www.scanex.com/en/publications/pdf/publication17.pdf
4. A. Ivanov, B. Golubov, V. Zatyagalova, On Oil and Gas Seeps & Underground Fluid Discharge in the Southern Caspian Based on Space Radar Data // Earth Exploration from Space, 2007, № 2, p. 62-81. ( http://www.scanex.com/en/publications/pdf/publication27.pdf )
5. Иванов А.Ю. Слики и плёночные образования на космических радиолокационных изображениях // Исследование Земли из космоса, 2007, № 3, c.73-96.
6. Иванов А., Голубов Б., Затягалова В. Прогноз нефтегазоносности и поиск нефтяных месторождений в море по данным космической радиолокации // Технологии ТЭК, 2007, № 4, с. 40-47. ( http://www.oilcapital.ru/edition/technik/archives/technik
   /technik_04_2007/113048/public/113068.shtml)
7. Иванов А.Ю., Затягалова В.В. Картографирование пленочных загрязнений моря с использованием космической радиолокации и географических информационных систем // Earth Exploration from Space, 2007, № 6 (в печати).