Skip to 0 minutes and 0 seconds The effects of climate change on our planet have never been higher profile. But how often do you hear the people marching in the streets talking about the ocean? Due it’s sponge-like, heat absorbing properties, the ocean is actually helping control climate change. But in doing so the temperature of our seas increased by almost 1 degree Celcius over the past century. This might not sound like much, but the ocean and its inhabitants are very sensitive to temperature change. Many marine species, including fish, shellfish and turtles, have changed their distribution and movement patterns. In general, species are moving towards the poles, leaving tropical areas worst affected. The implications for fisheries and food security are dramatic and are already causing political conflict.
Skip to 0 minutes and 56 seconds Due to the excess heat, coral reefs are also bleaching and dying on a global scale. Unfortunately, higher temperatures are not the only effect of greenhouse gases. Up to a third of the extra CO2 is absorbed by the ocean, causing it to become more acidic – almost 30% more than it was in the pre-industrial age. This makes it difficult for calcium based species such shellfish, corals and certain algae to form their hard shells and skeletons, while dissolving those that already exist. Such ocean acidification is sometimes called the ‘evil twin’ of the greenhouse effect, given its potential to devastate ocean ecosystems in the future.
Skip to 1 minute and 41 seconds Of course climate change will also bring physical effects – sea level rise, increased storminess and changes to ocean currents, all with further negative effects on marine species. So what can we do? The straight forward answer is - reduce our emissions of greenhouse gases, but in the meantime we can mitigate some of these effects. Improved and more co-operative fisheries management should stabilise fish stocks, while marine protected areas can increase the resilience of marine ecosystems. It is hoped that such measures will bide us enough time to make the more dramatic societal changes that are really needed.
Climate change and our oceans
In this video, Dr Bryce Stewart explains how our oceans are heating up and becomng more acidic, with serious consequences for sea life and for humans alike.
What can be done? Dr Stewart outlines the solution.
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