A fisheye view of the Great Barrier Reef Marine Park, AustraliaThe earliest known photosynthesising marine fossil we have record of goes back 3.5 billion years. The ocean was producing oxyg...Image by Janelle Lugge / Shutterstock
A kelp forest flanks a sea lion in the Pacific Ocean off San Benito Island, MexicoLand plants evolved from green marine algae, so we owe the ocean for all of the oxygen that comes from them...Image by Reinhard Dirscherl / Ullstein Bild via Getty Images
A NASA satellite image shows heat radiating from the PacificOxygen is critical to the health of oceans. Their warming has caused a decline in phytoplankton levels by 40 percent since 1950. ...Image by AFP / NASA / Handout
A layer of toxic foam from sewage and industrial waste on Yamuna river in New Delhi, IndiaThere are serious consequences to humans discharging nitrogen and phosphorus into our waterways thr...Image by Biplov Bhuyan / Hindustan Times via Getty Images
Smoke billows from a large steel plant in Inner Mongolia, ChinaOceans are becoming more acidic as a result of absorbing excess carbon dioxide gas released in the atmosphere by human activit...Image by Kevin Frayer / Getty Images
Scores of dead fish surface on the banks of the Guanabara Bay in Rio de Janeiro, BrazilAs the planet&rsquos polluted atmosphere traps more heat, the oceans get warmer. Last year saw new hig...Image by Ricardo Moraes / Reuters
A fish farm in Maoer Lake, Jiangsu Province of ChinaThe percent of seafood supplied by the aquaculture industry has risen from a mere 7 percent in 1974 to over 52 percent of all seafood con...Image by Zhou Haijun/ Visual China Group via Getty images
Garbage floats in the Ganga river along the ghats of Varanasi, IndiaA toxic soup of marine debris that gets swept into sewers, storm drains and waterways and eventually out to sea via river...Image by Avishek Das / Sopa Images/ Lightrocket via Getty Images
