According to the study published in the journal Earth System Science Data, the ocean has absorbed over 90% of the warming that has happened in the last 50 years, with the remaining heat absorbed by the land, cryosphere, and atmosphere.
Earth’s energy balance: A quick recap
- It is the difference between the quantity of energy received from the Sun and the amount of energy sent back into space.
- It is also referred to as the radiation budget.
- The majority of the energy received by Earth from the Sun is in the form of visible light and ultraviolet radiation.
- This energy is absorbed by the Earth’s surface and atmosphere, which then emits infrared radiation back into space.
- The balance of incoming and outgoing radiation is critical for keeping the Earth’s temperature and climate stable.
- Any imbalance between the two has the potential to cause global warming and climate change.
The following are the study’s key findings: Accumulation of Heat
- According to the analysis, manmade emissions amassed 381 zettajoules (ZJ) of heat on the planet between 1971 and 2020.
- This equates to a heating rate of about 0.48 watts per square metre (Earth Energy Imbalance, or EEI). The difference between incoming and outgoing solar radiation is referred to as the EEI.
- According to the research, approximately 89% of the accumulated heat is held in the ocean, 6% on land, 1% in the atmosphere, and approximately 4% is available for melting the cryosphere.
Implications
(1) Land Heat Accumulation
- Heat collected on land raises ground surface temperatures, which may promote soil respiration and result in the release of carbon dioxide.
- Depending on the climatic and meteorological conditions and causes, increased soil respiration will most likely reduce soil water.
(2) Inland Water Bodies and Permafrost Thawing
- Since 1960, heat storage in inland bodies has grown to about 0.2 ZJ. It was roughly 2 ZJ for permafrost thawing.
- Heat accumulation in inland water raises lake water temperatures, creating ideal circumstances for algae blooms.
- According to the experts, the heat content of permafrost might release methane and carbon dioxide into the atmosphere.
(3) Ocean and Troposphere heating
- According to the revised estimations, the upper ocean (0-300 and 0-700 metres depth) has absorbed a significant portion of the heat.
- Between 2006 and 2020, ocean warming rates in the 0-2,000 metre depth reached a new high of about 1.03 watts per square metre.
- Because of increasing heat accumulation, the troposphere is also warming.
(4) Cryosphere heating
- From 1971 to 2020, the cryosphere (the frozen water element of the Earth system) accumulated about 14 ZJ of heat.
- Half of the uptake was caused by the melting of grounded ice, while the other half was caused by the melting of floating ice.
- The Antarctic Ice Sheet supplied around 33% of total cryosphere heat gain, with Arctic sea ice coming in second at 26%.
Source: https://www.downtoearth.org.in/news/climate-change/oceans-absorb-90-of-human-induced-planet-warming-study-88879#:~:text=About%2089%20per%20cent%20of,journal%20Earth%20System%20Science%20Data.