The warmer air and ocean surface temperatures brought on by climate change are altering coral reef communities and affecting the many organisms that use coral reefs as a habitat.
To understand how this is happening we need to realise that the ocean is like a massive sink that absorbs carbon dioxide. This process has two polar opposite effects on the planet. As the ocean absorbs carbon dioxide it is ‘helping’ to slow down global warming but it is also changing the oceans chemistry.
The increase of carbon dioxide in seawater decreases the pH level or becomes more acidic. This is called ocean acidification. With ocean acidification, corals cannot absorb the calcium carbonate they need to maintain their skeletons. This leads to reduced coral growth rates and weakened structural integrity. If nothing is done to reduce carbon dioxide emissions into the atmosphere, ocean acidification will increase and more coral will be damaged or destroyed.
As temperatures also continue to rise so do the number of negative effects on coral, these are:
- Infectious disease outbreaks
- Mass coral bleaching
- Sea level is rising and so is the sedimentation that can lead to the smothering of coral
- Storm patterns have changed being more frequent and intense, resulting in the destruction of coral reefs
- Increase in rainfall also leads in an increase in runoff of freshwater transporting land based pollutants into the ocean. These pollutants contribute to algal blooms that cause murky water and thus reduce the much needed light.
Some of the land based contribution factors are raising livestock, fertilizing crops, deforestation and burning fossil fuel for heat and energy.
So how can we help to improve the overall coral reef condition? We need to shrink our carbon footprint to reduce greenhouse gases. Listed below are some of the practical steps we can take towards this:
- Drive less
- Reduce, reuse or recycle
- Print less, download more
- Use less water
- Reduce the use of chemicals we use in our gardens
- Do not dispose of household chemicals into storm water drains
- Choose sustainable seafood
If coral reefs are lost, vital habitat will be lost too. The future health of coral reefs and many marine organisms depends on our ability to reduce our carbon dioxide emissions on a global scale. Nature is calling us to change our ways.