Climate change and marine ecosystems

Climate change is profoundly affecting marine ecosystems, disrupting biodiversity, altering habitats, and jeopardizing the livelihoods of communities reliant on marine resources. Amongst key stressors are ocean acidification, rising sea temperatures and sea level rise.

Warming of the oceans

The rising sea temperatures have an impact on marine species' life cycles, migrations, and reproductive patterns. Coral reefs, for instance, are highly sensitive to heat, and as a consequence they are experiencing bleaching. Coral bleaching not only diminishes biodiversity but also undermines reef ecosystems, which support about 25% of marine species.

Ocean acidification

The increased carbon dioxide absorption by oceans results in ocean acidification. This is impacting the ability of calcifying organisms such as shellfish, corals, and plankton to build their calcium carbonate structures. This poses a threat to the foundational levels of the marine food web, with cascading effects on fish and larger predators.

Habitat loss

The rising sea levels and melting polar ice are impacting habitats for species such as polar bears and seals. Meanwhile, coastal habitats like mangroves and seagrasses, crucial for carbon sequestration and providing nursery grounds for marine life, are being eroded.

Disrupted ecosystems

Marine ecosystems face shifts in species composition as some organisms migrate to cooler waters, leaving others unable to adapt. This redistribution disrupts predator-prey dynamics and fishing industries dependent on specific species.

Socioeconomic Impacts

These ecological changes threaten global food security, as fisheries decline due to species loss and habitat degradation. Communities dependent on fishing face economic hardships, while nations experience conflicts over shifting fish stocks.

Urgent mitigation efforts, such as reducing greenhouse gas emissions and protecting marine habitats, are crucial to curb these effects. Additionally, fostering sustainable fishing practices and establishing marine protected areas can help buffer marine ecosystems against the ongoing challenges posed by climate change.