FROM JUNE, meteorological signs foretold that a drought would hit the Amazon region. Droughts in the rainforest are typically fuelled by high sea surface temperatures in the North Atlantic Ocean on the northeast and in tropical Pacific Ocean on the northwest.
Scientists particularly watch out for high sea surface temperature in the tropical Pacific, as it marks the onset of El Niño, the warm phase of a recurring climate pattern El Niño-Southern Oscillation. Many drought episodes in the Amazon have occurred during intense El Niño conditions such as those recorded in 1926, 1983, 19971998, and 2010. These conditions weaken the "Walker Circulation"-an atmospheric circulation in the Pacific Ocean over the tropics. Walker Circulation resembles a loop consisting of rising air in the west and sinking air in the east. During an El Niño, the rising moist air, which is meant to bring rainfall, does not reach the continent of South America. Instead, there is more sinking and dry air moving towards the land, setting the stage for a drought.
This year, the World Meteorological Organization declared the onset of El Niño in the tropical Pacific on July 4, but said that the conditions were moderate. Then what caused such a severe drought in the Amazon?
JOCHEN SCHÖNGART
Amazon has seen more droughts, floods in the past 15 years than in a century
The Amazon basin is in transition to an anthropogenic disturbance-dominated regime
This story is from the {{IssueName}} edition of {{MagazineName}}.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber ? Sign In
This story is from the {{IssueName}} edition of {{MagazineName}}.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber? Sign In
A SPRIG TO CARE FOR
Punarnava, a perennial herb, is easy to grow and has huge health benefits
DIGGING A DISASTER
Soapstone mining near Dabti Vijaypur village has caused many residents to migrate.
REVIEW THE TREATMENT
Several faecal sludge treatment plants in Uttar Pradesh suffer from design flaws that make the treatment process both expensive and inefficient
MAKE STEEL SUSTAINABLE
As India works to double its GDP by 2030, its steel industry must balance growth with sustainability. By embracing policies like the Steel Scrap Recycling Policy 2019 and adopting green technologies, India is paving the way for a more sustainable future in steel production
Can ANRF pull off the impossible for India?
Anusandhan National Research Foundation is expected to reorient India's innovation goals but funding issues, old mindsets remain a drag
TROUBLED WOODS
Forests are a great bulwark against climate change. But this is fast changing. AKSHIT SANGOMLA travels through some of the pristine patches of the Western Ghats to explore how natural disturbances triggered by global warming now threaten the forest health
BLINDING GLOW
The science is clear: increased illumination has damaging consequences for the health of humans, animals and plants. It’s time governments introduced policies to protect the natural darkness and improved the quality of outdoor lighting.
GROUND REALITY
What happens when the soil loses the ability to grow healthy, high-yield crops on its own?
GM POLICY MUST BE FARMER CENTRIC
On July 23, the Supreme Court of India directed the Union government to develop a national policy on genetically modified (GM) crops for research, cultivation, trade and commerce through public consultation.
Vinchurni's Gandhi
A 96-year-old farmer transforms barren land into a thriving forest in drought-prone region of Satara