Why in news?
One of the biggest revelations of the Special Report On The Ocean And Cryosphere In A Changing Climate, released in September 2019 by the Intergovernmental Panel on Climate Change (IPCC), was how much the global ocean has heated up.
How is it heating?
- Since 1970, the report said, 90% of the excess heat generated due to greenhouse gas (GHG) emissions has been absorbed by the ocean.
- 2019 also showed the largest single-year spike in ocean heat.
- The heat is mostly trapped in the top 2,000m of the ocean, which is also home to the bulk of marine life forms.
What it tells us?
Marine heat readings offer a more comprehensive idea of global heating, since surface temperatures are also affected by periodic weather systems like the El Niño effect.
Impact
- Marine heat readings offer a more comprehensive idea of global heating, since surface temperatures are also affected by periodic weather systems like the El Niño effect.
- Warmer ocean is a major contributor to Polar ice melt, which in turn contributes to sea-level rise.
- The biggest immediate effect of a warming ocean, though, is the worldwide decline in coral reefs
- Loss of tiny marine organisms which form the bedrock of the global marine food chain
- Fish stocks worldwide have been falling, and as fish species migrate to cooler waters, livelihoods are affected
Way forward
Countries and industries must slash their GHG emissions and move to non-fossil fuel energy
