theglobeandmail.com
Massive Land Transformation to Drylands Creates Global Crisis
A UN report reveals that an area larger than India has irreversibly shifted from humid to dry land since 1990, impacting food systems, poverty, and global water resources, with climate change and agricultural practices cited as key contributors.
- How do agricultural practices and climate change interact to exacerbate the global increase in aridity?
- The conversion of humid lands to drylands is a permanent change driven by increased greenhouse gas emissions. These emissions trap heat, exacerbating water evaporation and reducing soil moisture. Agricultural practices, such as fertilizer use and tillage, further contribute to dryness by reducing soil biodiversity and increasing runoff. This creates a vicious cycle where drier soil supports fewer plants, leading to less moisture retention.
- What are the immediate and specific global impacts of the significant land transformation from humid to dry regions?
- An area larger than India has transformed into dryland over the past three decades, impacting food systems, increasing poverty, and causing water shortages globally. This is due to more than three-quarters of the Earth's land becoming permanently drier between 1990 and 2020, with over 40% of the global land mass now classified as drylands. Twice as many people live in drylands today compared to 1990.
- What long-term impacts and potential solutions exist to address the escalating global crisis of permanent aridity beyond current agricultural practices?
- Continued high greenhouse gas emissions will expand drylands further, impacting regions like the Mediterranean, parts of South America, and Southern Africa. Melting ice and permafrost, not fully accounted for in the report, worsen the situation, especially in boreal forests. Sustainable agricultural policies focusing on healthy soil are crucial to mitigate this, creating a positive feedback loop by reducing emissions and enhancing soil moisture retention.
Cognitive Concepts
Framing Bias
The framing is largely neutral, presenting the scientific findings of the UN report. The use of strong quotes from experts adds weight to the severity of the issue without overtly pushing a particular narrative. The headline accurately reflects the report's core finding.
Language Bias
The language used is largely neutral and factual, relying on data and expert quotes. The use of terms like "existential threat" is impactful but justifiable given the report's findings.
Bias by Omission
The report's limitations are acknowledged by both the authors and an outside expert. Prof. Overpeck points out that the report understates the problem by not considering ice melt and permafrost thaw, which contribute significantly to drying. This omission is a significant weakness and should be addressed in future iterations.
Sustainable Development Goals
The report highlights the significant expansion of drylands globally due to climate change, impacting water resources, food systems, and increasing poverty. This directly relates to climate action as the increased aridity is a consequence of rising greenhouse gas emissions and associated temperature increases. The melting of ice and permafrost further exacerbates the issue.