In pictures: the impact of the climate crisis and human activity on our oceans

Our oceans bear the brunt of the impacts of global warming, having absorbed around 90% of the heat generated by rising emissions to date, according to the United Nations.

These changes in temperature lead to a cascade of effects, from ice melt to ocean acidification. They not only harm marine biodiversity, but affect the lives of 680 million people living in low-lying coastal areas and the 2 billion inhabitants of coastal megacities affected by flooding, cyclones and more.

A photography competition by Climate Visuals seeks to raise awareness and understanding of how the climate crisis and human activity are impacting the ocean.

These images from the Ocean Visuals collection explore how rising temperatures are harming marine life, and how coastal communities are working together to tackle the effects of global warming on the environment.

The climate crisis is causing fish populations to decline, meaning hatcheries like these are vital to reviving fish populations in the wild.

With lower fish stocks, the livelihoods of fishers and their families are put under strain as incomes fall.

Rising ocean temperatures cause corals to expel the microscopic algae living within them, keeping them alive. The coral then loses its bright colour and dies, a process known as coral bleaching.

Many coral reefs are experiencing bleaching around the world, so restoration is vital to ensure the marine life that depend on these habitats are protected.

Artificial reefs like these help to not only provide a habitat for fish, but also to reduce soil erosion by breaking the force of the waves before they reach the shores.

The climate crisis is increasing soil salinity in many regions of the world, destroying flora and fauna which provide food and shelter for both plants and animals.

As sea ice melts, Inuits in the Arctic region struggle to carry out their daily tasks like hunting due to the lack of reliably solid sea ice.

Sea-level rise as a result of the climate crisis is creating challenging commutes like this for many coastal communities.

Coastal villages around the world are increasingly experiencing extreme flooding, with citizens having to migrate further inland.

The climate crisis has forced coastal communities to adapt their way of life to endure through floods.

To combat flooding, Fiji's government sponsors several mangrove reforestation initiatives like this throughout the country. Mangroves increase the resilience of coastal communities by serving as a natural wave barrier.

As sea levels rise, shoreline erosion must be addressed with protective measures like these that control how sand moves.

Every year, an estimated 11 million tonnes of plastic enter our oceans, according to the Ocean Conservancy. Volunteers like those pictured above offer their time to remove this waste and sort through it to recycle or repurpose different items.

These photos emphasize the need to protect our oceans – the planet’s greatest carbon sink – or we risk losing the range of benefits they provide us with, from breathable air to the future of food supplies.