Science Education through Earth Observation for High Schools. Module 7: Marine Pollution

About 60 percent (3.6 billion) of the world population lives within 60 kilometres of the coast, and this number is rapidly increasing. The oceans cover about 70% of the Earth’s surface and influence people’s everyday lives no matter whether they live - whether near the coasts or far inland. They influence global climate as well as regional and local weather, serve serve as transport routes and represent a source of food, wealth and employment. Fisheries and aquaculture provide a large proportion of the world's protein - around 40% of animal protein in the developing world. The sea floor and continental shelves are a source of important minerals, including oil and natural gas. Coastal areas are popular destinations for recreational activities. The oceans contain some of the most diverse ecosystems on earth; coral reefs and the deep sea are home to a diversity of species equal to that found in the Earth’s rain forests. How best to protect the ocean environments is thus a topic of great importance for biodiversity, and for the health, wealth and well-being of future generations.

The aim of the eLearning tutorial presented here is to increase awareness among high school students of the damage done by marine pollution, and what may be done by individuals and society to protect valuable marine environments. Through carefully selected examples, students will understand how the state of the oceans may impact their everyday lives, even if they live many hundred kilometres away from the coasts and don’t eat fish. The tutorial covers the main sources of marine pollution, the impact of different pollutants, methods to detect pollution, and ways in which pollution may be prevented and environmental damage minimised. There are sections on oil pollution, harmful algal blooms, litter, invasive species, and invisible pollutants such as chemicals, heavy metals, thermal and noise pollution. Throughout the main focus is on the monitoring of different types of marine pollution using a range of remote sensing techniques, each with their own strengths and limitations.

Oil spills, for example, can be detected using radar images from satellites, In the case of larger spills, a suite of airborne sensors at microwave, infrared and optical wavelengths may be used to provide information about the position and extent of a spill, its relative thickness and potentially the composition of the oil. Eutrophication arising from anthropogenic input of nutrients such as nitrogen compounds and phosphate may be monitored with ocean colour sensors. Thermal pollution from the input of cooling water from industry and power stations may also be monitored using a range of infrared and microwave satellite sensors. Carefully selected case studies demonstrate how the different sensors are used, individually and in synergy, to provide a thoroughly modern system for monitoring pollution and its impacts on the marine environment.