- GS 1: Important Geophysical phenomena such as earthquakes, Tsunami, Volcanic activity, cyclone etc., geographical features and their location-changes in critical geographical features (including water-bodies and ice-caps) and in flora and fauna and the effects of such changes.
- Recently, Global Coral Reef Monitoring Network, along with the Australian government released the Status of Coral Reefs of the World 2020 report where it has described about the condition of coral reef in present-day world.
- Coral reefs have suffered a lot in the past three decades. Yet, they are resilient and would be able to withstand challenges posed by a warming world.
- The 1998 coral bleaching event killed 8% of the world’s coral.
- Subsequent events between 2009 and 2018 killed 14% of the world’s coral.
- Since 2010, almost all regions had exhibited a decline in average coral cover.
- According to estimates, coral reefs would experience further declines in the coming decades as sea temperatures arose.
Reasons of coral distress
- Most declines in global coral cover were either due to rapid increase in sea surface temperature (SST) anomaly or sustained high SST anomaly.
- There were 20% algae on the world’s coral reefs in 2019 than in 2010. This increase in the number of algae, was associated with declines in the amount of hard coral.
Resilience of coral reefs
- On the other hand, the increases in global coral cover between 2002 and 2009 and in 2019 showed that coral reefs globally remained resilient and could recover if conditions permitted.
- For instance, coral reefs in east Asia, which has 30% of the world’s coral reefs, had more coral on average in 2019 than they did in 1983.
- It happened despite the area being affected by large-scale coral bleaching events during the last decade.
- This showed that high coral cover and diversity might confer a degree of natural resistance to elevated sea surface temperatures.
What need to be done?
- Local pressures on coral reefs should be reduced to maintain their resilience in the years to come.
- Data collected in the field should also be monitored to understand the status of the trends in coral reef condition.