Abrupt transition to irreversible damage in the overdrafted Sacramento Valley aquifer system.

August 4, 2026| Source: Proceedings of the National Academy of Sciences of the United States of America

Groundwater extraction decreases water pressure in aquifer systems, causing reversible or irreversible deformation of the water-bearing layers that manifests as recoverable or permanent displacements of the land surface, respectively. Detecting and forecasting when and where an aquifer system transitions from a reversible, poroelastic regime, to an irreversible, inelastic regime remains a crucial challenge given the complex, heterogeneous nature of aquifer systems. Here we leverage high-resolution measurements of ground deformation and groundwater levels from 2016 to 2022 to characterize both regimes at the regional scale and show that a critical transition occurred in large areas of the Sacramento Valley during California's 2020-2022 extreme drought. Our analysis reveals that, while deformation remained primarily poroelastic during the 2016-2020 interdrought period, land subsidence in areas of intense groundwater extraction accelerated abruptly in 2021, with subsidence rates exceeding the inferred poroelastic rates by several decimeters per year. Such rapid and extensive land subsidence indicates severe inelastic compaction and loss of storage capacity of the underlying aquifer system, which pose a serious threat to California's water resources and infrastructure. A comparison of present-day deformation with historical groundwater levels reveals that this abrupt transition was not predictable based on the available groundwater records alone.

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Multiband condensate of magnons in two dimensions.

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Physical/TechSeptember 27, 2026

Indirect reciprocity with dual private assessment.

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Physical/TechSeptember 26, 2026

A genetic program for rapid initiation of axillary meristems at the onset of flowering.

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Physical/TechSeptember 26, 2026

David Botstein: A pioneering geneticist and educator 1942-2026.

David Botstein, who died on February 27, 2026, was a towering figure in the field of modern molecular genetics. His research career was largely focused on the development of methods to better understand biological systems, beginning with his early work on Salmonella phage P22 and yeast, where he exploited the use of conditional lethal mutations as suppressors to identify genes with common functions and to order them in a pathway. He is best remembered for developing restriction fragment length p

Physical/TechSeptember 26, 2026

Ultra-narrowband organic room-temperature phosphorescence achieved by boosting low-frequency vibronic coupling.

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