Global-scale water security and desertification management amidst climate change

Area of Science:

• Environmental Science
• Ecology
• Climate Science

Background:

• Drylands cover 46% of Earth's surface, supporting diverse species, cultural heritage, and ecological processes.
• 3 billion people inhabit drylands, facing significant water insecurity and desertification.
• Dryland ecosystem services and health are declining due to desertification, water scarcity, and climate change.

Purpose of the Study:

• To analyze the impacts of desertification, water scarcity, and climate change on dryland ecosystems.
• To project the number of people affected by these impacts under different global warming scenarios.
• To identify effective policy frameworks and solutions for dryland sustainability.

Main Methods:

• Analysis of global warming impacts on dryland populations under the Shared Socioeconomic Pathway SSP2.
• Assessment of woody encroachment drivers like land use change and altered rainfall.
• Review of existing research on policy frameworks and adaptation strategies.

Main Results:

• Projected increases in affected dryland populations with rising global temperatures (951M at 1.5°C to 1285M at 3°C).
• Widespread woody encroachment altering biodiversity and reducing ecosystem services in various regions.
• Projected expansion of semi-arid areas in some regions (Mediterranean, Southern Africa, Americas) and shrinkage in others (India, China, East Africa).

Conclusions:

• Sustainable land management (SLM) and integration of indigenous local knowledge (ILK) are crucial for dryland resilience.
• Early warning systems, adaptation, and mitigation are essential for addressing climate change impacts in drylands.
• Alignment with Sustainable Development Goals (SDGs) is vital for effective policy and action in dryland management.