More than 75 percent of the globe became permanently drier over the past three decades, according to a report from the United Nations Convention to Combat Desertification (UNCCD).
The report, published Monday, found that about 77.6 percent of the globe became drier from 1990 to 2020, more than it did over the preceding three decades.
During this period, the parts of the earth classified as drylands expanded by about 1.66 million square miles, an area bigger than India. Such lands now comprise more than 40 percent of the globe, according to the UNCCD.
Nearly 8 percent of the planet crossed the line from the non-dryland to dryland classification in recent decades, many of which were once humid, and a further 3 percent of similar areas could cross that threshold by the end of the 21st century without a reduction in greenhouse gas emissions, the group warned in its report.
UNCCD attributes much of the increasing aridity on human-caused climate change, which affects both temperature and rainfall. Although the permanent dryness described in the report is distinct from drought conditions, the western U.S. has similarly seen warmer temperatures increase the risk of devasting fires due to reduced snowpack in recent years.
If drylands further expand, a number of regions are likely to be affected, UNCCD found — areas that would see their drylands widen in a high-emissions scenario include the midwestern U.S., central Mexico, broad swaths of southern Africa and all of the Mediterranean.
“Unlike droughts—temporary periods of low rainfall—aridity represents a permanent, unrelenting transformation,” UNCCD Executive Secretary Ibrahim Thiaw said in a statement. “Droughts end. When an area’s climate becomes drier, however, the ability to return to previous conditions is lost.”
“The drier climates now affecting vast lands across the globe will not return to how they were and this change is redefining life on Earth,” Thiaw added.
