Global Aridification Threatens Food Security as Drylands Expand Over a Third of Earth’s Surface

Over the past three decades, a vast expanse of land nearly a third larger than India has transitioned from humid conditions to drylands, where agriculture becomes difficult. This shift is part of a broader trend that has seen 40% of Earth’s land, excluding Antarctica, become classified as drylands.

A significant portion of the planet’s surface has experienced drier conditions, with three-quarters of the land now facing more arid climates, which may persist permanently, according to a report by the UN Science Policy Interface. The consequences of these changes are expected to have severe long-term impacts, particularly on global food and water security.

The effects of increasing aridity have already been devastating, with Africa experiencing a 12% loss in its GDP between 1990 and 2015 due to these changes. Projections indicate that these economic losses will worsen, with Africa’s GDP forecasted to decline by 16% and Asia’s by nearly 7% in the next five years.

Ibrahim Thiaw, the UNCCD’s executive secretary, emphasized the difference between temporary droughts and permanent aridity. Once an area becomes arid, it cannot return to its previous state, marking a permanent transformation of the land.

This ongoing aridification is affecting crop yields, with crops like maize expected to face significant reductions in areas like Kenya by 2050. Drylands are characterized by severe water loss, with 90% of rainfall evaporating, leaving only a small fraction for vegetation.

By mid-century, two-thirds of the world’s land is projected to store less water, exacerbating the difficulties in regions already struggling with water scarcity. These changes have already led to a growing global water crisis, with nearly 2.3 billion people living in drylands as of 2020, a significant increase from 1990.

Climate change, largely driven by greenhouse gas emissions, is a major contributor to the expansion of drylands, though human activities like over-extraction of water and unsustainable farming practices also play critical roles.

The UN study, for the first time, warns that burning fossil fuels is driving permanent drying trends across large parts of the world, with potentially catastrophic impacts on water availability. Experts highlight that the degradation of soil, caused by intensive agriculture, also fuels biodiversity loss and worsens natural disasters like floods and wildfires.

In response to this escalating crisis, experts call for urgent action. Solutions include curbing greenhouse gas emissions, implementing sustainable agricultural practices, improving water management, and promoting reforestation. Experts like Mark Maslin from University College London stress the importance of global governance in addressing desertification.

Rising aridity exacerbates poverty, accelerates resource depletion, and leads to more severe food and water insecurity, disproportionately affecting vulnerable communities, particularly in regions with limited capacity to adapt. These changes are not only an environmental challenge but also a profound injustice for those most affected by them.