Save a whale, save a planet.

• Author: Dicaprio, Leonardo

In 1997, a dramatic scene played out near Los Angeles as a newborn grey whale was discovered stranded in Marina del Rey. It had become separated from its mother during the annual migration from Alaska to Mexico. Hundreds of volunteers commandeered boats and moving vans and used makeshift stretchers to move this lone baby female whale over 100 miles to San Diego in a desperate attempt to save her life.

Named JJ by her rescuers, she arrived weak, dehydrated and disoriented--but after 18 months in care, she was restored to health and released back into the wild. While many celebrated that day, the challenges JJ overcame were nothing compared to the threats she and her entire grey whale species now face 20 years later.

THAT THREAT IS CLIMATE CHANGE.

Today, our oceans are under immense pressure as their waters absorb much of the carbon dioxide and other greenhouse gases pumped into the air by human activity, resulting in a 30 per cent increase in acidity. The progress of the human race, particularly since the Industrial Revolution, has resulted in devastating impacts to our entire climate, and those impacts are particularly prevalent in our oceans.

Seashells are weaker, massive ancient coral formations are bleaching and essential ecosystems are dying. The marine food chain is endangered: clams, oysters, lobsters and crabs, which are a dietary staple for large sea creatures such as seals, otters and walruses, are under the threat of extinction. Most worrisome of all, plankton, amphipods (tiny shrimp-like creatures) and other microscopic organisms that sustain mighty whales and fish of all types and sizes are becoming harder to find. This frightening trend means JJ will likely starve to death before the end of her normal lifespan, and much of the sea life that billions of humans depend on will disappear.

Unlike other threats to the ocean, such as plastic pollution and overfishing, these changes are not always easy to see, but there are obvious warnings. More than half of the world's 17 penguin species are now endangered, largely due to climate change-related declines in their food supply. Common clams are smaller than ever--quite literally disappearing before our eyes--and humans, too, will suffer from that loss. A protein found in a common clam shell has been shown to cure cancers. Where do we turn when it's gone?

As a result of climate change, the world's oceans are already warming to the point where they can no longer absorb our pollution...