Scientists study rare bloom in the Atacama Desert, one of the driest places on Earth

John Yang:

We leave you tonight with a beautiful sight in an unexpected place. William Brangham tells us about it.

William Brangham (voice-over):

These wildflowers, gently blowing in the breeze are delicate and rare because they live in one of the driest places on Earth, a place usually hostile to any kind of flowering plant.

This is the Atacama Desert, a sprawling stretch of land squeezed between the Pacific Ocean and the Andes Mountains, mostly in Chile. It normally gets just 2 millimeters of rain every year, but this July and August, some parts of the desert got 60 millimeters of rain.

But rain isn't the only condition needed for this landscape to be transformed, says Victor Ardiles, the head of botany at Chile's Museum of Natural History.

Victor Ardiles, Museum of Natural History, Chile (through translator): We understand that there is a threshold that must exceed 15 millimeters of rainfall for the seas to begin to activate. But in addition to water or precipitation, we need temperature, we need a certain number of hours of daylight, and we also need humidity.

William Brangham (voice-over):

This year, those proverbial stars aligned and the blooms are bursting. Ariel Orellana studies plant biotechnology at the Andres Bello University.

Ariel Orellana, Andres Bello University (through translator):

The Atacama Desert is the driest in the world and also one of the territories with the highest solar radiation and ultraviolet radiation on the planet. This means there are very adverse conditions for the growth of any living being.

And the fact that a plant can grow in these conditions is quite remarkable. We wanted to investigate it and understand the mechanisms it uses to survive in such a hostile environment.

William Brangham (voice-over):

This floral display has drawn tourists and scientists for the opportunity to understand just how these plants do it.

Cesar Pizarro Gacitua, National Forest Corporation, Chile (through translator):

Coordination and joint work with academics and researchers studying the physiology of this plant is very important. How can it produce enough food and perform photosynthesis to withstand extreme conditions?

William Brangham (voice-over):

Orellana says understanding these individual plants is key in the age of climate change.

Ariel Orellana (through translator):

This plant has the ability tolerate drought very well, which is a serious and growing issue in global agriculture. Therefore, by understanding the genome, the genetic information of this plant, and at the same time identifying which genes are expressed when it is exposed to drought, we could potentially use that knowledge to develop crops with greater drought tolerance.

William Brangham (voice-over):

Most of these flowers will disappear by November as South America edges closer to its summer season. For PBS News Weekend, I'm William Brangham.