Earth Day 2012: The Top 5 Threats to Our Oceans, Part Two

April 22nd, 2012

Continued from Part One, focused on Overfishing and Marine Pollution. Read part one here.

Climate Change

Several studies have shown that in the past century our planet has seen climate change and warming unlike any other time in recent history. While this has many effects on land, such as more erratic weather patterns, it effects the oceans in two main ways: sea temperature and sea level rise.

In the past century, the temperature of the ocean has raised 0.18°F (0.1°C). Factors such as ozone depletion and increased solar activity contribute to this rise. As the surface of the water absorbs heat and the temperature rises. Some sub-tropical seas have shown a 1 degree surface temperature rise in the past half-century.

Warmer than usual marine environments also give way to marine invasive species. That is, species that do not typically inhabit a given area but with abnormal temperatures can survive in the new environment. These species can deplete a once healthy ecosystem by introducing disease and competing for food.

As ocean water warms, it expands. Due to increased sea temperature, the sea level is rising. Ice melting on land also contributes to the rise in sea level. Sea levels are expected to rise between 2.5 and 6.5 feet by 2100, a level that would swamp many cities along the East Coast of the U.S. There are other more dire scenarios some environmental scientists believe to be possible. Such as, if the Greenland ice sheet were to completely melt, the sea level could rise up to 23 feet, enough to submerge London and Los Angeles.

Ocean Acidification

Above-normal sea temperature is a contributing factor to coral bleaching. Ocean acidification also plays a major part. Over the last 250 years, the ocean has absorbed 530 billion tons of CO2 which has increased ocean acidity by 30%. Under these harmful circumstances, once healthy coral loses its algae pigmentation and expels zooxanthellae, causing it to turn white.

Acidity reduces carbonate- the mineral used to form the shells of many species such as lobster and mussels as well as smaller species which the food chain heavily depends on.

Due to ocean acidification, coral reefs are depleting twice as fast as rainforests.

Marine Habitat Loss and Destruction

70% of the world is covered by the ocean, yet only .6% of our worlds oceans are protected.

Factors such as overfishing, coral bleaching, boating, oil spills and other industrial pollution all cause serious damage to our oceans. Coral reefs bare most the brunt of marine habitat loss. Over 15% of the worlds coral reefs have already been lost. 30% of those still existing are directly threatened by human impacts.

Costal development can lead to runoff and erosion that is harmful to the surrounding marine area. This occurs all along our coastlines, small island developments and coastal swamps and marshes.

Marine Protected Areas (MPAs) are similar to National Parks on land. While they are not closed off completely to human activity, they only allow a certain minimal and regulated presence.

Hope everyone has a great Earth Day and celebrates it in their own way. We encourage you to share our Earth Day 2012 page. For every share, we at Seathos will collect 1 lb of trash from our local beach in Venice, CA.

Earth Day 2012: The Top 5 Threats to Our Oceans, Part One

April 20th, 2012

The tireless and iconic ocean conservationist and activist Sylvia Earle has said that “what we do or fail to do in the next 10 years will have a magnified impact on the next 10,000 years.” This is a call to arms of sorts, a plea to shed ignorance and indifference and learn more about the dangers our oceans face, influencing us all to take positive steps towards helping to heal our oceans, rather than cause them more harm.

To celebrate Earth Day on April 22nd, Seathos is raising awareness of the top five threats our oceans face today: Overfishing, pollution, climate change, ocean acidification and marine habitat loss.


Our oceans are not an endless bounty of food, but they are being treated as such. Currently, 75% of the world’s fishstocks are fished faster than they can reproduce. More than 3.5 billion people depend on the ocean for their primary source of food. In 20 years, this number will double to 7 billion.

Not only does overfishing deplete once thriving marine ecosystems, but it is also has a direct negative impact on the human race as well. Abundant fish populations are vital to the survival of millions of people who depend on seafood production for food and jobs. With a growing human population and dwindling fish stocks, over fishing jeopardizes the livelihoods of many.


Trash, chemicals, fertilizers and other harmful contaminants find their way into the ocean every minute of every day. Various factors contribute to water pollution, such as improper disposal of industrial waste, marine dumping, sewage, wastewater and agricultural runoff.

Marine litter is now 60-80% plastic, and can reach 90% in certain areas. Over 100,000 marine mammals and 1,000,000 seabirds die each year from ingesting or becoming entangled in plastic.

Plastic particles, some large, some microscopic, are scattered all throughout the ocean, but perhaps the most startling evidence of marine plastic pollution is the Great Pacific Garbage Patch, a gyre of marine litter located in the North Pacific. The gyre’s exact size is debatable, but studies have ranged from sizing it between twice the size of Hawaii and as large as the entire continental United States.

Head on over to Seathos’ Earth Day 2012 Campaign page and take part in our 1 for 1 pledge. For every share the page receives the Seathos team will collect 1lb of trash from our local beach in Venice, CA.

Stay tuned for Part Two, highlighting climate change, ocean acidification and marine habitat loss.