The Background

Planet Earth is known as the ‘blue planet’. This is because water covers nearly three-quarters of its surface, giving us the deep blue of the world ocean. The oceans contain dissolved salts (~3.5% by weight) making the water undrinkable for humans. However oceans make up 90% of the Earth’s biosphere, or habitable volume for life, and 80% of all living organisms, having an average depth of 3700 meters (12,100 feet). This is a total volume of 1.35 billion cubic kilometers or 320 million cubic miles! That is enough water to fill 534,000,000,000,000 (534 trillion) Olympic sized swimming pools!

The world ocean is divided into five main oceans (a), which we call the Arctic, Atlantic, Indian, Pacific, and Southern. The largest of these, the Pacific Ocean, covers nearly half the globe from end to end. This vastness makes the Pacific the most important in terms of two inter-related services that the oceans provide to the planet: support of life and regulation of climate.

World Atlas - Ocean challenges

Life first evolved in the oceans nearly 3.8 billion years ago. This started with tiny microscopic single-celled organisms called cyanobacteria. These cyanobacteria used chlorophyll to photosynthesize, harvesting energy from sunlight to produce simple sugars and other organic matter that they could then live on. Photosynthesis released oxygen into the air which slowly accumulated over billions of years in the Earth’s atmosphere, eventually allowing for the evolution of complex, multi-cellular life forms like the fish, birds, mammals, trees, and humans we know today.

In fact, phytoplankton (microscopic marine plants) are so numerous in the ocean, they are responsible for the oxygen in every other breath we take. Phytoplankton form the base of the food chain in the ocean, serving as food for the zooplankton (microscopic marine animals) that in turn serve as food for fish and mammals in the sea.

The marine food web is an integral part of Earth’s climate system. This is because the most important chemical element for life, carbon, is also involved with regulating the temperature in the Earth’s atmosphere and the global heat balance. Carbon in the atmosphere in the form of carbon dioxide gas, or CO2, is an efficient absorber of heat, helping to trap a portion of the energy radiated on Earth from the Sun. The oceans naturally store carbon, absorbing CO2 from the atmosphere. Phytoplankton and other ocean life absorb carbon during photosynthesis. Some of the CO2 will escape within a year, but eventually the ocean life dies and sinks, carrying the carbon with it to the deep ocean. Once there, the carbon is locked away from warming the surface for millennia due to the slow circulation of the deep ocean. In this way, the ocean’s carbon cycle can cool the Earth’s climate over time.

The Problems

The oceans are vast but that doesn’t mean that humans don’t have a large impact. Human activity has released millions of tons of plastic pollution, which accumulates in the oceans. Humans have also over-fished dozens of marine fish species and have altered the CO2 concentration and temperature of the atmosphere and oceans with fossil fuel consumption. Together these have put a strain on the ocean’s ability to support healthy ecosystems and maintain a habitable climate as we progress into the future.


Plastics are found in or are involved with transporting or storing nearly all the products we use today. Most of this plastic is single-use. Some finds its way into a landfill or recycling center; however, a significant amount unfortunately makes its way directly into the environment as pollution. These plastics blow in the wind, or find their way into freshwater streams and rivers, which all eventually lead to the ocean.

Over the past decades, all of this plastic pollution has been accumulating in the centers of each ocean basin. Ocean currents move around in big circles similar to the whirlpool in a toilet. The circular currents push any debris towards the center where debris piles up over time. Today there are five “Great Garbage Patches” in the ocean, each the size of Texas or larger! These garbage patches are thick with broken down bits of plastic that fish, turtles, and sea birds mistake for food, often choking them or polluting their bodies with indigestible plastic.


Over-fishing is another problem with our oceans. One billion people count on seafood as a daily source of protein in their diet. Mankind today is much more efficient than ever before at catching all of this fish because of advances in ships, nets, lines, and fish finding technology. This has set up an unsustainable situation in which we harvest more fish each year than the ecosystem can naturally produce. There were at least six times more fish in the sea in 1900 than in 2000 and worldwide about 90% of large predatory fish stocks like tuna and cod have already disappeared.

Overfishin - ocean challenges

400 tons of jack mackerel caught using a purse seiner

Collapsing fish stocks are bad for the environment. Removing fish from the food web means less food to feed whales, sharks, and dolphins. The fish and larger marine animals are eventually replaced with jellyfish and other less tasty organisms that signal an ecological dead zone. These dead zones further reduce the amount of fish that can be supported in nearby regions.

Ocean Warming and Acidification

Ocean warming and acidification also cause problems for the world’s oceans. Mankind furthers these problems because of our demands for fossil fuels and consumer goods. The heat trapping properties of CO2 in the atmosphere warm the Earth’s surface. Much of this excess heat gets absorbed into the oceans. Phytoplankton and other ocean life near the sunlit surface depend on cold, nutrient-filled waters returning from the ocean depths for nourishment. Warmer ocean waters near the surface act as a barrier to this upward mixing; thus, a warming ocean means fewer nutrients are able to sustain the marine food web over time. In fact due to this process, the best prediction for the future of ocean ecosystems sees an overall reduction in marine life

The oceans also absorb about a quarter of the excess CO2 in the atmosphere from fossil fuel emissions and other sources. Carbon dioxide acts as an acid when it dissolves in seawater, lowering its pH. High acidity or low pH is similar to the “bite” of tasting a fresh can of Coca-Cola or the “sting” of fresh citrus juice on a cut. Many organisms in the ocean are sensitive to pH, or the acidity level, especially those that produce calcium carbonate shells. These are species like mollusks, crustaceans, reef-building corals, and some species of phytoplankton. As the oceans become more acidic, these animals find it harder and harder to produce their shells that they need to survive.

Coral reefs are especially vulnerable to the rising temperatures and acidity of the oceans caused by excess CO2. When reefs get too hot, the corals lose their symbiotic algae, which provide the corals with much needed nutrition and give them their characteristic vibrant colors. As the ocean pH continues to decline, many coral reefs are struggling to produce new calcium carbonate to keep up with yearly damage or build new reef. The ocean is already 30% more acidic today than it was 250 years ago and this is only increasing faster.

Ocean Acidification - ocean challenges

Coral Reef before and after warming temperatures and ocean acidification (c).

 The Solutions

There are plenty of things individuals can do to improve oceanic issues like decreasing consumption patterns, particularly the use of plastics. Use reusable shopping bags at the grocery, convenience, retail stores, etc. instead of single-use plastic bags. Fill a reusable container for daily water consumption instead of drinking plastic bottled water. Refrain from drinking through plastic straws. Bring reusable eating utensils, instead of taking the plastic ones at take-out restaurants. Choose products made of natural, biodegradable plastics like corn, soy and hemp! Make sure to recycle all available plastic types (#1-7). Every piece of refused or properly recycled plastic is one less piece that has a chance of finding its way into our oceans! To learn more about plastic pollution, check out these organizations: Coastal Care, Plastic Pollution Coalition, and Surfrider. They are making waves!

In addition to reducing plastic consumption to protect our oceans, as individuals and as governments we can help curb the tide of the drastic state of over-fishing in our oceans. The single best option is to refrain from consuming fish and other seafood that is caught in an unsustainable manner. Sustainably harvested seafood is taken from the oceans at a rate slow enough that allows for the fishery to naturally replenish itself, thus allowing for a stable fishery over time. Another option is to consume farm-raised seafood. These fisheries are managed to raise large quantities of seafood for human consumption (e.g. salmon or shrimp) and therefore do not deplete wild fisheries in the natural ecosystem. The Monterey Bay Aquarium provides a Seafood Watch List, which is an excellent resource for determining which types of seafood are best and worst to consume based on sustainability practices for five regions around the U.S.

Conservation is another proven method for improving depleted fish stocks around the world. The establishment of Marine Protected Areas, where marine activities such as fishing, boating, scuba diving, etc. are limited or restricted all together are very effective at helping marine ecosystems restore their natural biodiversity. These Protected Areas have not only helped the area under protection but areas adjacent to the boundaries have shown increased abundance of fish and other wildlife.

Individuals can help the problem of over-fishing too. Support regional and national efforts for sustainable fishing practices, including safe catch limits and controls on bycatch. Support local conservation efforts of marine habitat that include proper management, monitoring, and enforcement of the protected areas. To learn more visit: Overfishing- a global disaster, World Wildlife Fund, and National Geographic.

While the above suggestions are easier for an individual to undertake the threat of rising temperatures and acidifying waters for our oceans and its biodiversity is difficult to address. Rising CO2 in the atmosphere is the main cause of increased temperatures and acidifying waters. The rising CO2 emissions are mostly caused from fossil fuel burning which provides 80% of global energy use. There is still time to save ocean life from the worst of these effects but we must act now. Together, we as global people, have to transfer our energy needs from those centered on fossil fuel consumption to low-carbon alternatives such as solar, wind, geothermal, and nuclear options. This will slowly stem the flood of climate warming and acidifying CO2 into the atmosphere and oceans.

Scientists and oil extracting companies currently are exploring geo-engineering solutions to remove some of the CO2 that is already circulating in the atmosphere and store it away in deep ocean waters or bedrock underground where it is locked away for thousands of years. These efforts include stimulating the ocean’s natural carbon cycle by fertilizing the ocean surface with nutrients like iron and nitrogen to allow phytoplankton to bloom (although currently banned by the United Nations because of unknown impacts to ecosystems, i.e. the precautionary principle) or by pumping CO2 deep underground where it can react with rock to form new carbonate minerals. Only then will we be able to reverse some of the ocean acidification and warming trends that we’ve already set in motion.

How Can Hemp Help?

Hemp absorbs carbon dioxide as it grows which in turn reduces climate impact! Growing more hemp could reduce ocean acidification impacts.

Hemp foods have a high Omega 3 content, just like fish! But we don’t need to catch the fish while wiping out populations. Instead we can just grow hemp for grain and eat it in whole grain, crushed or oil form to ingest the same quantities of Omega 3! It’s far more efficient!



Interested in learning more? Visit:

Intergovernmental Panel on Climate Change

Ten possibilities for staving off catastrophic climate change

Woods Hole Oceanographic Institution

National Oceanic and Atmospheric Administration



(a) World Atlas. Large Map of Oceans of the World.

(b) Rojas, C. NOAA Photo Library. NOAA’s Fisheries Collection.

(c) Moyer, R. Impacts of Ocean Acidification on Coral Growth: Historical Perspectives of Core-Based Studies. USGS. Nov 2009

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