Tree‐Ring Insights Into Past and Future Streamflow Variations in Beijing, Northern China

Water Resources Research, Journal Year: 2025, Volume and Issue: 61(1)

Published: Jan. 1, 2025

Abstract As the largest city in northern China and capital of China, rapid increases Beijing’s water consumption recent years have made resources provision an increasing problem. To rationally allocate resources, it is important to obtain long‐term runoff information Beijing. In this study we develop a 236‐year chronology tree‐ring widths based on cores from Pinus tabuliformis four sampling sites. The resulting regression model reconstructs December–July Yongding River Beijing, with 49.5% variance explained, back 1786 CE. Among last 236 years, 1868, 1956, 1991, 1998, 2018, 2021 were extremely high years; 1900, 1906, 1999, 2000 low years. Comparison reconstruction results climate grid data demonstrated large magnitude change North during period. Linkage analysis between reconstructed large‐scale vapor indicated that occurred negative phases Pacific Decadal Oscillation, which may be influenced by East Asian Summer Monsoon. Projections indicate flow will increase future. Supported policies such as Ecological Water Supply South‐to‐North Diversion, regional vegetation productivity increased substantially since 2000. Vegetation growth interacts volume. It unclear how long these continue.

Language: Английский

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An Attempt of Combining Oak and Pine Trees to Enhance Monsoonal Precipitation Reconstruction in the East Qinling Mountains

International Journal of Climatology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 6, 2025

ABSTRACT Short‐term meteorological observations often limit our understanding of regional climate change over historical periods. Dendroclimatology provides an effective means for overcoming this limitation by extending the record. In China, most tree‐ring studies focus on coniferous species. But study innovatively combines both Liaodong oak and Chinese pine trees to establish a new synthesis chronology in East Qinling Mountains. The showed significantly high correlation with observed April–June precipitation ( r = 0.747, n 41, p < 0.001), while individual or failed meet threshold quantitative reconstruction R 2 > 40%). Using chronology, we reconstructed 163‐year series that offers robust spatiotemporal representation marginal Asian Summer Monsoon (EASM) region through spatial analysis comparison surrounding hydroclimate reconstructions. several extreme drought periods (1871–1881, 1917–1931, 1957–1973) wet (1888–1899, 1906–1916, 1985–1995) were detected from reconstruction. Additionally, it significant synchronisation EASM indices 0.02) at interannual time scales, PDO AMO influenced variability multidecadal scales. These findings demonstrate combined broad‐leaved chronologies can effectively capture large‐scale atmospheric circulations.

Language: Английский

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Reconstruction of July temperature based on tree-rings during 1845–2002 in North China

Frontiers in Forests and Global Change, Journal Year: 2025, Volume and Issue: 8

Published: March 26, 2025

The reconstruction of climate factor fields is essential for understanding large-scale change. We collected 30 tree-ring width chronologies and 29 meteorological stations data, conducted spatial correlation analysis between temperature stations, selected the timelines with high ( r &gt; 0.6), these data in North China. results showed that there was a significant maximum July p &lt; 0.05). Based on this, summer series reconstructed by Point-by-Point Regression (PPR). show are two warm periods (1856-1970, 1883-1952) cold (1871-1882, 1953-1996) China from 1845 to 2002. Morlet wavelet shows sequences have four periodic changes: 1-3a, 2-6a, 7-11a 13-18a. Cross he El Niño-Southern Oscillation (ENSO), Sunspot, Pacific Decadal (PDO) factors affecting change study area. In addition, we also analyzed distribution pattern Empirical Orthogonal Function (EOF) Rotational (REOF). patterns July: west, east, south north, west main pattern.

Language: Английский

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Hydroclimatic representativeness and reassessment of the predictive skill to reconstruct precipitation by the Dryness/Wetness Index from Chinese historical documents

Journal of Hydrology Regional Studies, Journal Year: 2024, Volume and Issue: 54, P. 101883 - 101883

Published: July 5, 2024

China The Dryness/Wetness Index (DWI) data from is widely utilized in palaeohydroclimate research. initial part of this data, covering the years 1470–1979 (original DWI), primarily generated records droughts/floods historical documents. However, extended over 1980–2000 (precipitation-based DWI) derived entirely instrumental precipitation measurements. To date, there no research on regional differences hydroclimatic representativeness original DWI. Moreover, when reconstructing using combined 1470–2000 DWI as a proxy and calibrating it with post-1950, overestimated reconstruction skill has not been evaluated. Therefore, utilizing crop yield reductions due to drought/flood disasters 1978 2008, we establish disaster-based following same method explore its skill. Disaster-based more sensitive East Central China, seasonal window lasting for five months distributed between April September. In contrast, reflects soil water Northeastern, Southeast coastal, Western regions China. Additionally, by comparing average predicted R-Squared summer precipitation-based (58.6 % 45.0 %, respectively), identify an overestimation 13.6 %. Even after excluding inflated R-Squared, remains highly reliable precipitation.

Language: Английский

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