El Nino caused record CO2 spike in 2015-16

• Scientists have found that 2015-16 El Nino-related heat and drought are responsible for the largest annual increases in atmospheric carbon dioxide (CO2) concentration .

Important highlights:

• 2015-16 El Nino-related heat and drought occurring in tropical regions of South America, Africa and Indonesia was responsible for the largest annual increases in atmospheric carbon dioxide (CO2) concentration.
• These three tropical regions released 2.5 gigatonnes (a billion tonnes) more carbon into the atmosphere than they did in 2011.
• In 2015 and 2016, OCO-2(Orbiting Carbon Observatory 2) recorded atmospheric carbon dioxide increases that were 50 per cent larger than the average increase seen in recent years preceding these observations.
• That increase was about three parts per million of carbon dioxide per year — or 6.3 gigatonnes of carbon.
• In recent years, the average annual increase has been closer to two parts per million of carbon dioxide per year — or four gigatonnes of carbon.
• These record increases occurred even though emissions from human activities in 2015-16 are estimated to have remained roughly the same as they were prior to the El Nino.
• The team compared the 2015 findings to those from a reference year — 2011 — using carbon dioxide data from the Japan Aerospace Exploration Agency’s Greenhouse Gases Observing Satellite (GOSAT).
• In 2011, weather in the three tropical regions was normal and the amount of carbon absorbed and released by them was in balance.
• Understanding how the carbon cycle in these regions responded to El Nino will enable scientists to improve carbon cycle models, which should lead to improved predictions of how our planet may respond to similar conditions in the future.

About El Nino:

• El Nino, means ‘little boy’ in Spanish. It is a weather system which re-emerges after a gap of about two to five years in the Pacific Ocean and its effects last for about 12 months on an average.
• El Nino leads to warming of sea surface temperatures, which in turn affects wind patterns and triggers both floods and droughts in different parts of the world.
• Such an event is usually characterized by extreme weather events in many parts of the world. Few places across the globe are also benefited by El Nino.
• El Nino, Spanish for ‘The little boy’, is a weather disturbance first noticed (and named) by fishermen off the coast of South America centuries ago.
• It makes weak monsoon rains in Indonesia and Australia and sometimes in India.

By: Vishal