Runoff – After a rainstorm, a river on the Meso-American coast discharges sediment and nutrient-laden water (fertilizer and other possible contaminents) to the Caribbean sea. [Photo: Malik Naumann, Marine Photobank] Almost 80% of marine pollution comes from land-based activities worldwide: industry, agriculture, or domestic.

For years, people have been treating the oceans like giant garbage dumps. They have assumed that the oceans are so large that all pollutants would be diluted to safe levels and not harm the ecosystem.  In reality they have not disappeared and some toxic man-made chemicals have even become more concentrated as they have entered the food chain.

Birds have played a major role in creating awareness of pollution problems.  For example, populations of bald eagles were decimated following World War II, when DDT was widely used as a pesticide.

DDT  washed into nearby waterways, where aquatic plants and fish absorbed it.  Bald eagles and other predatory birds such as Ospreys, Peregrine Falcons, and Pelicans, in turn, were poisoned with DDT when they ate the contaminated fish and the DDT and its relative toxins bioaccumulated in their fatty tissues.  The chemical interfered with the ability of the birds to produce strong eggshells. As a result, their eggs had shells so thin that they often broke during incubation or otherwise failed to hatch.  With the banning of DDT in the 1970s and 1980s, Bald Eagle and other predatory bird populations have recovered significantly.

Pollution from toxic chemicals is covered in the presentation:

MARINE POLLUTION – TOXIC WASTE – 170126

All presentation PowerPoint files in English are available under “Educational Material”

Some man-made ocean noises are causing whales and other marine animals to beach themselves.

The human-caused noise that is now in our oceans poses a significant and sometimes lethal threat to whales, dolphins, seal lions, seals, sea turtles, and other marine wildlife.  For example, in whales and dolphins, low frequency military active sonar (LFA) is causing tissue damage and bleeding around the ears, eyes, and brain, and large bubbles or holes in their organs – the result of decompression sickness, caused when the animals are frightened by the intense noise of LFA and surface too quickly.

Noise and light pollution is covered in the presentation:

MARINE POLLUTION – MAN-MADE NOISE AND LIGHT – 170126

All PDFs of the Oceans PowerPoint presentations are available under “Educational Material”.

Ocean acidification is threatening the life of many marine organisms, including crustaceans, mollusks, and coral reefs.

The oceans have absorbed 80% of all excess heat in the Earth’s system and about one-third of the carbon emissions released by humans over the past 200 years.  This is causing:

• Ocean warming, which is threatening coral, phytoplankton, and other marine life and is creating regions with levels of oxygen too low to sustain marine life.
• Changes in the ocean chemisty, referred to as ocean acidification, which can make it difficult for many marine animals to grow, build shells, reproduce and respond to other stresses.

The pteropod, or “sea butterfly”, is a tiny sea creature about the size of a small pea. Pteropods are eaten by organisms ranging in size from tiny krill to whales and are a major food source for North Pacific juvenile salmon. The photos below show what happens to a pteropod’s shell when placed in sea water with pH and carbonate levels projected for the year 2100. The shell slowly dissolves after 45 days.  Photo credit: David Liittschwager/National Geographic Stock. Used with permission. All rights reserved. National Geographic Images.

The CLIMATE CHANGE presentation provides an understanding of the major impacts of climate change on our oceans and also on the rest of the planet.

CLIMATE CHANGE – IMPACTS ON OUR OCEANS AND LAND – 170201

All PDFs of the Oceans PowerPoint presentations are available under “Educational Material”.

RELATED ARTICLES:

• Arctic faces further threat from ocean acidification (guardian.co.uk)
• Ocean acidity dissolving tiny snails’ protective shell –http://www.climate.gov/news-features/featured-images/ocean-acidity-dissolving-tiny-snails%E2%80%99-protective-shell

The oceans regulate our climate and provide us with food, jobs, transportation, and over half of the oxygen that we need to breathe.

The Oceans cover 70% of Earth’s surface and make up 95% of all the space available to life.  They are our life support system without which there would be no life.

(Courtesy of F. Hasler, et al, the National Oceanic and Atmospheric Administration, and NASA)

The INTRODUCTION presentation provides a general comprehension of why our oceans are so important:

WHY OUR OCEANS ARE SO IMPORTANT – 170102

All presentation PowerPoint files in English are available under “Educational Material”.