Climate Change

Why is Earth’s driest place flooding and snowing?

The Atacama Desert in Chile is witnessing rains like never before, including regions that never recorded rains in history

 
By Richard Mahapatra
Last Updated: Tuesday 12 March 2019
Representational Photo: Getty Images
Representational Photo: Getty Images Representational Photo: Getty Images

Last week, it rained so much in Atacama Desert — the driest place on the planet — that a waterfall that remained dry for 10 years has come to life.

Chile is witnessing extreme downpours causing floods, including in the Atacama Desert. The desert’s geography is its ecological destiny — the majestic Andes Mountains block clouds from the region, while the cold currents in the Pacific Ocean don’t trigger moisture-laden winds to keep the desert enveloped in water particles.

The annual rainfall in the region is just 15 millimetres (mm). It is only during the El Niño phenomenon that the rains increase due to warmer ocean currents. This happens once in two to 12 years, with a gap of five years. However, since last three years, the desert areas are witnessing not just heavy rainfall but also snowfall.

Climate scientists are now rushing to the region. Signs of a changing climate have been pronounced in recent years with the frequent recurrence of desierto florido, a unique phenomenon.

Desierto florido, or flowering desert, returned to the Atacama Desert in Chile in 2017 — four years before the usual time. The 127,000 square kilometre desert hosts the desierto florido once every five-seven years — when the desert blooms with over 200 species of flowers.

The extremely arid landscape — it is the proxy on earth for the settings of almost all movies on Mars — metamorphoses into an unbelievable world of colours. It is popularly believed that desierto florido attracts more people than a prime soccer event. Those who witness it invariably invoke a sense of devotional surrender to the mystique of nature.

In August 2017, nature wished to take a break from her routine; maybe to pause and shout out a message. This month, when the desierto florido returned to Atacama, it ditched its usual five-seven years cycle.

An unusual spell of rains preceded the flowering; almost putting at stake the place’s undesirable, but much-revered superlative of being the driest place on earth. Just two years ago, the desert had seen the flowering.

For hundreds of geologists and climate experts, who usually scavenge such harsh landscapes for clues to everything that concerns human existence, it raised many questions. In shock, many asked: why did it come back so early? Are regular rains the new identity of the desert? Will the desierto florido be frequently giving the desert a diametrically opposite ecological look? Or was it just a freak incident?

Arica, Chile’s northernmost city in Atacama, and just 18 km from the border of Peru, is fabled as having the lowest rainfall rate in the world. It has a world record for the longest dry spell — it didn’t rain here for 14-and-a-half years consecutively in the early 20th century.

In Antofagasta city, it rains just 1.8 mm a year. There is a wide network of weather stations in the region, but many stations in the Atacama never recorded any rain. Geological studies reveal the desert did not receive any rainfall between 1570 and 1971.

One feels a chill in the desert even during the day time — as it’s located on a high altitude. But such is the absence of water in its ecosystem that its 6,885 metre-tall mountains don’t have any glaciers. British scientists suggest that some riverbeds have been dry for over 120,000 years.

In May 2017, heavy rains lashed the region and continued for close to a month. The National Emergency Office of Chile’s Ministry of Interior and Public Security put the region on red alert. The municipality of Diego de Almagro in the region was affected by flooding from the Salado river. Tourists were stranded; nearby port towns were closed.

Though the government was still measuring the intensity of rain in November 2017, many media reports said the rainfall was more than 700 per cent of the annual average; in many places it was more than 1,000 per cent. This spell caused the untimely drought flowering.

Atacama is a mine of buried seeds of mallow flowers from earlier flowerings. The seeds come to life all at once. Of late, such extreme weather events are becoming part of the 21st century lore of Atacama.

On March 24, 2015, parts of the desert recorded 2.4 centimetre (cm) rain, or 14 years’ worth of rainfall, in just one day. In Antofagasta, it rained 2.2 cm or the region’s total rainfall of a year in just 12 hours. The usually dry Copiapo river was flooded. Chile declared a national emergency to facilitate relief and rescue operations.

Unlike the rain in May 2017, this extreme rain spell was triggered by the El Niño phenomenon. Usually, desierto florido coincides with this weather event.

Deputy Interior Minister Mahmud Aleuy said the flooding was the “worst rain disaster to fall on the north (of Chile) in 80 years”. And in October, the desert bloomed, the last one to keep the cycle of five-seven years —rated as the “most spectacular in 18 years”.

In July 2011, Atacama had a brush with another unusual event — snowfall. According to the Chilean government, the desert region received up to 80 cm of snow, never seen in the preceding 20 years.

“Ordinarily, the flashes of white in South America’s Atacama Desert rise from salt pans. But on July 7, 2011, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired these images, much of the white came from a far rarer commodity: snow,” NASA said in a press release.

In August 2013, residents witnessed another snowfall that they thought was the worst in three decades. Since they had never seen snow, even at such high altitudes, frequent snowfalls raised the fear of flooding as the snow melted.

Scientifically and figuratively, Atacama is the new landscape to witness the impacts of climate change. “The Atacama is so dry that as a child, I could read at night just by using the static electricity generated by my hand being rubbed against my bed linen,” Armando Azua-Bustos, founder & CEO, Atacama Biotech, was quoted as saying in media reports.

Armando is now steering scientific experiments to look at how life adapted to such a hostile environment, thus carrying clues to wider adaptation to climate change. Scientists pointed out that Atacama faced an abrupt change in climate to be fated to this condition.

Local residents of this lonely part of the planet had already perceived an imminent change in the climate. But they were not alone. Their “never before experience” with weather was also not a freak development, but part of a planetary level change sweeping across the globe.

And this change was unfolding in extreme weather events, often contrasting, spanning continents, geography and demography. As it turned out, in the long-term, all of us are victims of deadly weather events.

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