Joshua trees, an iconic species of the arid southwest of the United States, may disappear completely at the end of the century due to climate change, according to a new study.
A team from the University of California at Riverside used data from the Intergovernmental Panel on Climate Change to assess the impact of warming on the distribution of Joshua trees (Yucca brevifolia) in its namesake Joshua Tree National Park.
The park, which extends to both sides of the Colorado and Mojave deserts in southern California, is home to the largest concentration of species, which are not really trees but members of the agave family, which can sometimes Look like trees.
According to the team model, in an optimistic scenario whereby humanity can limit greenhouse emissions to some extent, tree cover would be removed by approximately 80 percent at the end of the 21st century.
But under a “business as usual” scenario, modeling indicates the complete elimination of a species dating from the Pleistocene era.
Lynn Sweet, the lead author of the study, told the Los Angeles Times that, under its pessimistic scenario, the park could see that the average warm temperatures in summer increase between five and nine degrees Fahrenheit (2.8 to 5 degrees Celsius) and three to seven inches (7.5 to 18 centimeters) less rain.
“If Joshua’s trees could survive those conditions, they would already be in them,” Sweet said.
It is said that the Joshua Tree, also the name of a seminal U2 album, was named by a group of Mormon travelers who crossed the Mojave Desert in the 19th century.
They gave him his name because he reminded them of the biblical figure Joshua raising his hands to heaven in prayer.