Top 5 impacts of climate change on our seas

1.  Ocean warming

Ocean warming is the increase in ocean temperature due to climate change. This increase in temperature has further impacts such as ocean deoxygenation, melting polar ice, coral bleaching and altering ocean currents.

2. Melting polar ice

The increase in global temperatures and ocean warming are leading to the melting of the polar ice. Every decade, 13% of Arctic sea ice is now shrinking due to climate change. The melting of polar ice contributes to sea level rise and reduces the habitat available for phytoplankton, krill, polar bears, and other marine species.

3. Sea level rise  

Over the last 140 years the global sea level has risen by up to 24 cm. This is due to thermal expansion and melting polar ice, which are both caused by ocean warming. Increased sea levels can result in flooding, habitat loss and coastal erosion.

4. Increased storm events

The increased storminess of seas due to climate change can impact marine life as well as human activities such as shipping and infrastructure. Combined with rising sea levels, storms will have a higher size and reach which can lead to extreme coastal flooding.

5.  Ocean acidification

The increase in uptake of CO₂ from the atmosphere as a result of rising emissions, changes the chemistry of the ocean and reduces ocean pH. This is known as ocean acidification and affects crustaceans such as crabs and lobsters by decreasing development and weakens the shells of mollusks such as dog whelks.

What can we do about it?

Nature based solutions  

Our seas will naturally store carbon. In fact, the ocean absorbs around 25% of all carbon dioxide emissions! Therefore, one way we can mitigate climate change is to protect and restore these natural, carbon capturing ecosystems.

One nature-based solution currently underway in Wales is seagrass restoration!  Seagrass captures carbon that is dissolved in our seas through photosynthesis and then stores this carbon in the sediment where it can remain for decades. Stopping carbon from reentering the atmosphere! The carbon captured by seagrass, along with similar carbon capturing processes from tidal marshes, mangrove forests, kelp, and phytoplankton, is called blue carbon.

Reduce your carbon footprint

To minimize the impacts of climate change on our seas we must reduce our carbon footprints (the amount carbon emitted by individuals, organizations, and communities). Actions we can take as individuals include reducing our consumption of energy, single-use plastics, fashion, and technology. As well as reducing food waste and travelling sustainably by using public transport, walking, or biking.

Use your voice

Whilst individual climate action is important, climate change is a global issue. Therefore, we also need to use our voices to push for larger climate change solutions! This can include protesting, voting, writing to your MP or any other activist action that calls for solutions to climate change. By inspiring others and working together we can amplify our voices and protect our seas.

References

Church, J.A. and White, N.J., 2011. Sea-level rise from the late 19th to the early 21st century. Surveys in geophysics, 32(4), pp.585-602.

Comiso, J.C., Parkinson, C.L., Gersten, R. and Stock, L., 2008. Accelerated decline in the Arctic sea ice cover. Geophysical research letters, 35(1).

Firth, L.B., Browne, K.A., Knights, A.M., Hawkins, S.J. and Nash, R., 2016. Ecoengineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment. Environmental Research Letters, 11(9), p.094015.

Gattuso, J.P., Magnan, A., Billé, R., Cheung, W.W., Howes, E.L., Joos, F., Allemand, D., Bopp, L., Cooley, S.R., Eakin, C.M. and Hoegh-Guldberg, O., 2015. Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios. Science, 349(6243), p.aac4722.

Small, D.P., Calosi, P., Boothroyd, D., Widdicombe, S. and Spicer, J.I., 2016. The sensitivity of the early benthic juvenile stage of the European lobster Homarus gammarus (L.) to elevated pCO2 and temperature. Marine biology, 163(3), pp.1-12.

Unsworth, R.K., Cullen-Unsworth, L.C., Jones, B.L. and Lilley, R.J., 2022. The planetary role of seagrass conservation. Science, 377(6606), pp.609-613.