Context:
A study conducted in 2023 revealed that the heat content of the world’s oceans has increased two to three times since the late 1980s.
Key Findings:
- In 2023, the heat stored in the top 2,000 meters of the world’s oceans was 286 Zetajoules (ZJ), which is more than the average from 1981 to 2010.
- The amount of heat in the ocean in 2023 was equivalent to about 4.6 billion Hiroshima nuclear bombs.
- The Atlantic, North and Western Pacific, and Southern Oceans are heating up faster than the rest of the world’s oceans because they absorb 90% of the heat from global warming.
Ocean Heat Content (OHC):
- Defined as the total amount of heat absorbed by and stored in the oceans and measurements of water temperature reflect the amount of heat in the water at a particular time and location.
- Measured in Joules.
- Water has a higher heat capacity than air, which means that it can store much larger amounts of heat.
Role of Ocean Heat Content:
- Affects Earth’s energy, water, and carbon cycles.
- Important indicator of Climate change.
- When the ocean warms, it releases heat and moisture into the atmosphere intensifying storms, causing severe weather events.
- Lowering the level of oxygen in the water.
- Rising ocean temperatures directly affect Corals.
Source: Down to Earth
Previous Year Question
With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct?
1. OMT is measured up to a depth of 26°C isotherm which is 129 meters in the south-western Indian Ocean during January-March.
2. OMT collected during January-March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean.
Select the correct answer using the code given below:
[UPSC Civil Services Exam – 2020 Prelims]
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (b)
Explanation:
The depth for the 26-degree isotherm is 50-100 meters, not 129 meters.
