Water quality is essential for public health, ecosystem health and the economy. Degraded water quality can occur as a result of pollution from sewage discharge, oil spills, industrial waste, agricultural runoff, storm water runoff, and sediment runoff. Impacts of poor water quality include exposure to disease and harmful chemicals, reduction in viability of impact economically important fisheries species, hypoxia events and destruction of ecosystems. As coastal populations and development increase, coastal environments become at greater risk for water quality issues.
Earth observations play a vital role in supplying decision makers with data and information about water quality. Ground-based (in situ) observations satellite observations can be used together to monitor and forecast water quality across the globe.
Declines in marine and coastal water quality cause detrimental impacts on the function and productivity of aquatic ecosystems. Excess nutrients can cause a shift in species composition and abundance, disrupting aquatic ecosystems and causing including depleted oxygen and excessive algal growth. Coral reefs can become smothered by nutrient stimulated algae and sediments from coastal development. Other pollutants, such as heavy metals, pesticides, oil and radioactive waste can cause illness and mortality in marine organisms. Sustained ocean and coastal observations are crucial for monitoring and mitigation of these environmental impacts.
Poor water quality can expose human populations to toxins and pathogens. Human exposure to toxins and pathogens can occur through ingestion of contaminated seafood or direct exposure. Degraded water quality can also have severe consequences on local economies by contaminating and harming populations of seafood species and damaging the tourism industry. With a growing number of people living and visiting coastal areas, water quality monitoring and forecasting is becoming increasingly important. Managers rely upon Earth observation data and information to make water quality related decisions such as beach and fisheries closures.