For the first time in a decade, the Atacama Desert, renowned as the driest on Earth, has witnessed a remarkable spectacle: plants blooming in the middle of winter. This rare phenomenon, a carpet of white and violet hues covering a portion of the desert, is a direct result of unseasonal rainfall in northern Chile during the Southern Hemisphere’s fall. About 0.4 inches (11 millimeters) of rain fell in mid-April, a significant event that, combined with the morning fog known as “camanchaca,” activated vegetation that can remain dormant for up to 15 years.
Two of the first species to paint the landscape this year were the “pata de guanaco,” with its vibrant fuchsia-colored flowers, and the white “sighs of the field.” The flowering has occurred over an area spanning between 115 and 155 square miles (300 to 400 square kilometers), according to César Pizarro, head of Biodiversity Conservation at the National Forestry Corporation (Conaf) in Atacama. Typically, a full flowering desert, which occurs in spring due to winter rains, can extend over about 5,800 square miles (15,000 square km), showcasing more than 200 species in bloom.
This unusual winter bloom is linked to the El Niño-Southern Oscillation (ENSO) cycle. The rains that triggered this event fell in March, mirroring the situation in 2015, where rainfall in March activated vegetation in winter. However, the future of this bloom remains uncertain as the El Niño phase is transitioning to La Niña. This shift means the drought will return, potentially hindering the desert’s ability to reactivate its vegetation.
The lack of pollinators poses a significant challenge to the desert’s biodiversity. With low temperatures, bees, moths, beetles, and other pollinators are absent. This creates a decoupling between flowering and pollination, potentially jeopardizing seed production. While herbaceous plants possess a self-pollination mechanism, it activates late in flowering, raising concerns about the long-term implications for seed replenishment.
The implications of this unusual event on the desert’s long-term biodiversity are complex. With climate change, anomalous events like this year’s winter bloom could become more frequent. If this pattern persists, annual plants may struggle to reproduce, potentially leading to a decline in diversity or paving the way for invasive species. The Atacama Desert’s future, like the fate of its winter blooms, remains uncertain, highlighting the critical need for ongoing research and understanding of the delicate balance of this unique ecosystem.
