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This study examines Holocene phreatic overgrowths on speleothems (POS) found in brackish pools of Mallorca Island’s coastal caves. It traces the evolution of knowledge about these deposits, beginning with initial morphogenetic observations in the late 1970s. Recent research, involving 138 U-Th datings from eight caves, reconstructs the late Holocene sea-level history over the last 4,000 years. Findings include a sea level position at 25 cm below the pre-industrial times ‒occurring between 3.89 and 3.26 ka BP‒, followed by a rapid rise to current levels, remaining stable from 2.84 ka BP until the early 20th century. The paper also discusses glacial isostatic adjustment models, one of which is similar with the obtained POS data, linking sea-level rise to West Antarctica’s ice melt. Today, these crystallizations are partially submerged in the coastal phreatic waters, due to the gradual rise in sea level linked to modern (industrial) global warming; since 1900 the sea-level has risen by about 17.3 cm, with the rate of rise accelerating to 2.05 mm/year in the recent decades.
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This content will become publicly available on October 15, 2026
Modern sea-level rise breaks 4,000-year stability in southeastern China
Quantifying physical mechanisms driving sea-level change—including global mean sea level (GMSL) and regional-to-local components (that is, sea-level budget)—is essential for reliable future projections and effective coastal management1,2. Although previous research has attempted to resolve China’s sea-level budget from the 1950s3,4, these studies capture short timescales and lack the long-term context necessary to fully assess modern sea-level rise in southeastern China5—one of the world’s most densely populated regions with immense socioeconomic importance6. Here we show that GMSL followed three distinct stages from 11,700 years before present (BP) to the modern day: (1) rapid early Holocene rise driven by the deglacial melt of land ice; (2) 4,000 years of stability from around 4200 BP to the mid-nineteenth century when regional processes dominated sea-level change; and (3) accelerating rise from the mid-nineteenth century. Our results arise from spatiotemporal hierarchical modelling of geological sea-level proxies and tide gauge data to produce site-specific sea-level budget estimates with uncertainty quantification. It is extremely likely (P ≥ 0.95) that the GMSL rise rate since 1900 (1.51 ± 0.16 mm year−1, 1σ) has exceeded any century over at least the past four millennia. Moreover, our analysis indicates that at least 94% of rapid modern urban subsidence is attributable to anthropogenic activities, with localized subsidence rates often exceeding GMSL rise. Such concurrent acceleration of global sea-level rise and rapid localized subsidence has not been observed in our Holocene geological record.
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- Award ID(s):
- 2103754
- PAR ID:
- 10650856
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature
- Volume:
- 646
- Issue:
- 8086
- ISSN:
- 0028-0836
- Page Range / eLocation ID:
- 856-864
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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