Global and Planetary Change最新文献

{"title":"Response of braiding intensity in a braided reach of the Lower Yellow River to upstream damming","authors":"Yuchen Liu ,&nbsp;Junqiang Xia ,&nbsp;Meirong Zhou ,&nbsp;Yifei Cheng ,&nbsp;Shanshan Deng ,&nbsp;Chiyuan Miao","doi":"10.1016/j.gloplacha.2025.104911","DOIUrl":"10.1016/j.gloplacha.2025.104911","url":null,"abstract":"<div><div>Adjustments in braiding intensity have a direct impact on the stability of river regime and flood-control security in braided rivers. However, there still lacks consistent calculations of braiding intensity, and how it responds to upstream damming remains largely unclear. Therefore, incorporating the effects of large central bars and sharp bends, a refined braiding index (<em>BI</em>_R) was proposed on the basis of a widely-used channel count index. Subsequently, a 299-km-long braided reach of the Lower Yellow River was selected as the study reach. The <em>BI</em>_R demonstrated reliable performance in quantifying the dam-induced variations in braiding intensity in the study reach. Furthermore, utilizing Landsat imagery along with hydrologic and topographic data, the linkage between the braiding intensity variation and upstream damming was revealed. The main findings are obtained as follows: (i) an overall reduction in braiding intensity occurred in the study reach following the construction of the Xiaolangdi Reservoir, with the value of <em>BI</em>_R decreasing from 0.918 to 0.674 in 2000–2022; (ii) alteration of flow-sediment regime caused by upstream damming was identified as the primary driver of the braiding intensity reduction, including the decrease in intra-annual variability of discharge hydrograph, the fall in rising and recession rates of flood events and the reduction in incoming sediment load; (iii) channel lateral confinement acts as a critical facilitator for braiding intensity reduction in dammed rivers, particularly under conditions of continuous channel degradation; and (iv) the enhancement of longitudinal channel stability due to bed material coarsening contributed to the reduction in braiding intensity, and also slowed down its decreasing rate. Overall, this study provides a valuable methodology to help understanding the evolution in braided rivers due to upstream damming and support the river management in an era of increasing anthropogenic intervention.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"253 ","pages":"Article 104911"},"PeriodicalIF":4.0,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental and metabolic influences on daily to hourly element/Cashell of Tridacna derasa cultured under elevated Ba2+ background concentration conditions","authors":"Haotian Yang ,&nbsp;Hong Yan ,&nbsp;Chengcheng Liu ,&nbsp;Nanyu Zhao ,&nbsp;Shan Liu ,&nbsp;Pengchao Zhou ,&nbsp;Guozhen Wang ,&nbsp;Hanfeng Wen ,&nbsp;Tao Han ,&nbsp;Jun Li ,&nbsp;Jialong Hao ,&nbsp;Ruiying Li ,&nbsp;John Dodson ,&nbsp;Xuxiang Li","doi":"10.1016/j.gloplacha.2025.104908","DOIUrl":"10.1016/j.gloplacha.2025.104908","url":null,"abstract":"<div><div><em>Tridacna</em> spp. has been demonstrated to be ideal for paleoclimate study. Some element/Ca_shell ratios of <em>Tridacna</em>, such as daily Fe/Ca_shell and Mn/Ca_shell have been identified as potential proxies in tropical cyclone reconstructions. However, the environmental implications of daily to hourly Ba/Ca_shell, Sr/Ca_shell, and Mg/Ca_shell remain ambiguous due to the complexity of the combined effects of environment and physiology on growth. Here, a laboratory culture experiment was carried out to explore the factors that affect the element/Ca_shell of the inner and outer layers of the <em>Tridacna</em> T1 specimen, as well as the incorporation mechanism of the Ba²⁺, Sr²⁺, and Mg²⁺ into the inner shell layer. The results showed that the daily to hourly Ba/Ca_shell of the inner and outer layers could respond to the input of exogenous Ba²⁺ in the background seawater. The ion-transport mode for Ba²⁺ and Sr²⁺ may be different in the inner layer (intercellular transport) and outer layer (intracellular transport) due to the different metabolic activity. Ba/Ca_shell of the inner layer was significantly positively correlated with Ba/Ca_water (<em>r</em> = 0.37, <em>p</em> &lt; 0.01), and significantly negatively correlated with water temperature after detrended (<em>r</em> = −0.45, <em>p</em> &lt; 0.001). Under high Ba/Ca_water level (45 times more than natural seawater), the incorporation ability of Ba²⁺ into the inner shell layer probably be improved, Ba²⁺ appears to incorporate synchronously with Sr²⁺, which may result in a significant positive correlation between Ba/Ca_shell and Sr/Ca_shell (<em>r</em> = 0.78, <em>p</em> &lt; 0.001). This synchronous incorporation likely disrupted the expected relationship between Sr/Ca_shell and water temperature, rendering it insignificant. Additionally, Mg²⁺ incorporation into the inner shell layer might appear to follow an independent mechanism, distinct from those of Ba²⁺ and Sr²⁺.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"252 ","pages":"Article 104908"},"PeriodicalIF":4.0,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144221345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Pacific Walker Circulation driven by Interdecadal Pacific Oscillation on precipitation variability in the North China Monsoon Marginal Region over the past five centuries","authors":"Xiaoen Zhao ,&nbsp;Mao Hu ,&nbsp;Feng Chen ,&nbsp;Shijie Wang ,&nbsp;Tiyuan Hou","doi":"10.1016/j.gloplacha.2025.104913","DOIUrl":"10.1016/j.gloplacha.2025.104913","url":null,"abstract":"<div><div>The Asian Summer Monsoon system has exerted significant impact on the ecological environment and socio-economic development of North China. Understanding the variability of monsoon precipitation and its underlying drivers in the context of anthropogenic warming necessitates the development of high-resolution precipitation reconstructions extending beyond the instrumental record. This study presents a novel tree ring network comprising 869 cores from 12 site chronologies in the North China Monsoon Marginal Region (NCMMR). A Nested Principal Component Regression model is used to reconstruct August-to-July precipitation variability from 1512 to 2021. The results indicate that, compared to the preceding five centuries, the probability of extreme high and low precipitation events increased by ∼9 % and ∼ 2 %, respectively, during the Current Warming Period (CWP, 1850–2021), with a higher long-term mean precipitation of 465.39 mm. The standard deviation and coefficient of variation for precipitation during the CWP (48.24 mm and 10.36 %, respectively) exceed those of the Historical Period (1512–1849) (36.89 mm and 8.07 %, respectively), highlighting an increase in precipitation variability over time. Analysis of global sea surface temperature patterns reveals a strong linkage between precipitation and the Interdecadal Pacific Oscillation (IPO). This is supported by a significant negative correlation between precipitation and the IPO index (<em>P</em> &lt; 0.001), alongside the IPO's substantial contribution (25 % of explained variance) to precipitation variability. Additionally, precipitation exhibits a significant positive correlation with the Pacific Walker Circulation (PWC) index (<em>P</em> &lt; 0.001). Climate model simulations further demonstrate that IPO-driven variations in PWC intensity regulate interdecadal precipitation variability in the NCMMR using water vapor transport anomalies.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"253 ","pages":"Article 104913"},"PeriodicalIF":4.0,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lagged response of the inorganic carbon system at eastern edge of the West Pacific Warm Pool to the ENSO events","authors":"Xi Lu ,&nbsp;Liping Zhou","doi":"10.1016/j.gloplacha.2025.104910","DOIUrl":"10.1016/j.gloplacha.2025.104910","url":null,"abstract":"<div><div>As a vast and highly variable natural source of atmospheric carbon dioxide (CO₂), the equatorial Pacific holds a pivotal position in the global carbon cycle. Here we examine the inorganic carbon system and related parameters in the west subtropical-equatorial Pacific surface seawater during a research cruise from February to April 2023. We find that the distributions of dissolved inorganic carbon (DIC), CO₂ partial pressure (<em>p</em>CO₂), and their anomalies in the study area display typical “La Niña featured” patterns, despite the neutral phase of El Niño-Southern Oscillation (ENSO) then. Analyses on the interannual variations of February-to-April mean CO₂ fugacity (<em>f</em>CO₂) anomalies in the eastern West Pacific Warm Pool (WPWP) relative to the 3-month running mean of Niño3.4 index revealed a ~ 5-month lag between the ENSO events and the strongest response of <em>f</em>CO₂ at eastern edge of the WPWP. This lag can be attributed to the combined effect of climate system development, thermal and chemical equilibrium, and physical mixing. Our work highlights the need for sustaining observations of marine carbon system, especially in climate-sensitive areas.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"253 ","pages":"Article 104910"},"PeriodicalIF":4.0,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144230129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporally compounding droughts at the global scale: Distribution, propagation, and projection","authors":"Xingyu Zhao ,&nbsp;Zengchao Hao ,&nbsp;Runze Huang ,&nbsp;Aiqing Feng ,&nbsp;Vijay P. Singh","doi":"10.1016/j.gloplacha.2025.104905","DOIUrl":"10.1016/j.gloplacha.2025.104905","url":null,"abstract":"<div><div>Temporally compounding droughts (TCD), which are usually referred to as consecutive years of droughts or recurrent droughts, can lead to larger impacts on different sectors than those resulting from individual droughts occurring in isolation. Previous investigations of the changes in TCD mostly focused on case studies or selected events. However, systematic assessments of the distribution, propagation, and projection of TCD across the globe are still limited, which hinders the understanding of their risk in a changing climate. In this study, we leveraged annual precipitation and soil moisture from ERA-5 reanalysis products to define different types of TCD, including those based on meteorological droughts (TCD_M) and agricultural droughts (TCD_A), and explored their spatial distributions and propagations during historical periods (1950–2014), followed by future projections (2036–2100) based on model simulations from the Coupled Model Intercomparison Project Phase 6 (CMIP6). Several regions, such as southern North America, northern Africa, and Australia, are the hot spots of TCD. In addition, the probability of TCD_A conditional on TCD_M (as a measure of drought propagation) is higher in southern North America, Africa, and Australia. For the future period, the frequency of short-term TCD_M is projected to decrease in large regions across the Northern Hemisphere and increase in certain regions (e.g., northern South America, Mediterranean regions, southern Africa, and Australia). The projected frequency of short-term TCD_A based on surface soil moisture shows an increase for the majority of global land areas except for a few regions, such as central Africa and southern Asia. The findings of this study are useful for the impact assessment of droughts and the development of mitigation measures under a changing climate.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"253 ","pages":"Article 104905"},"PeriodicalIF":4.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface warming in summer over the Tibetan Plateau: Local and atmospheric circulation processes1","authors":"Fangying Wu ,&nbsp;Qinglong You ,&nbsp;Nick Pepin ,&nbsp;Shichang Kang ,&nbsp;Panmao Zhai","doi":"10.1016/j.gloplacha.2025.104904","DOIUrl":"10.1016/j.gloplacha.2025.104904","url":null,"abstract":"<div><div>Both ground surface temperature (Ts) and near-surface air temperature (T2m) in summer over the Tibetan Plateau (TP) are not only a critical control of the cryosphere, but also an important indicator of atmospheric heat sources, which have a significant impact on regional water resources and broader climate systems. However, their characteristics and mechanisms have not been systematically studied. Based on gridded observations and ERA5 reanalysis we use diagnostic methods such as surface energy budget, longwave radiation decomposition, and water vapor budget, to analyze the characteristics and mechanisms of summer Ts and T2m changes over the monsoon and westerly regions of the TP during 1961–2022, as well as the possible impact of atmospheric circulation on the changes. Summer Ts (T2m) over the TP has increased at a rate of 0.20 (0.29) °C/decade, with rates of 0.21 (0.31) and 0.19 (0.28) °C/decade in the monsoon and westerly regions, respectively. For summer Ts warming, the increase in downward longwave radiation caused by an increase in water vapor is the primary contributor, and snow-albedo feedback is the secondary contributor. The former accounts for 58.3 %/62.3 % of the warming in the monsoon/westerly regions, and the corresponding proportions for the latter are 31.3 %/15.1 %, respectively. These surface-based local processes also contribute to T2m warming through the regulation of surface turbulent fluxes. Besides, atmospheric circulation changes (mainly manifested as the weakening of westerly winds) have not only increased water vapor, but also enhanced anomalous warm advection near the surface, resulting in an extra T2m warming over the TP. This study shows that local feedback and atmospheric circulation are controlling the summer warming over the TP, in both monsoon and westerly regions.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"252 ","pages":"Article 104904"},"PeriodicalIF":4.0,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144212606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Astronomically-forced wildfire control on high-latitude peatland carbon accumulation rate in the Middle Jurassic","authors":"Dawei Lv ,&nbsp;Guibo Zheng ,&nbsp;Zhihui Zhang ,&nbsp;Man Lu ,&nbsp;Munira Raji ,&nbsp;Khairul Azlan Mustapha ,&nbsp;Tiantian Wang ,&nbsp;Luojing Wang ,&nbsp;Wenxu Du","doi":"10.1016/j.gloplacha.2025.104906","DOIUrl":"10.1016/j.gloplacha.2025.104906","url":null,"abstract":"<div><div>Peat has been a vital terrestrial carbon reservoir on Earth since the Devonian period, serving as a precursor of coal and impacting the global carbon cycle and climate change. The Jurassic is a typical greenhouse period in geological history, marked by the accumulation of numerous coal seams worldwide. However, the processes governing peatland carbon accumulation during this period remain poorly understood. In this study, we focus on the ∼60.9-m-thick No. B2 coal seam of the Middle Jurassic Xishanyao Formation in the high-latitude Junggar Basin, NW China. Time series analysis of natural gamma logging data reveals a sedimentation rate of ∼2.3 cm/kyr and a duration of ∼2.6 Myr for the coal seam. By considering the carbon loss during coalification, the carbon accumulation rates of peatland were 41.10–52.74 g C/m²·a, showing a gradually decreasing trend from the bottom to the top of the coal. The high inertinite content in the coal exhibits typical charcoal characteristics, indicating frequent peatland wildfires. The strong negative correlation between carbon accumulation rate and inertinite abundance suggests that frequent wildfires have reduced the carbon accumulation of peatlands. Spectral analysis indicates that peatland carbon accumulation rates may be regulated by wildfire activity linked to 405-kyr orbital cycles. This study offers novel insights into the influence of wildfire activity on organic carbon burial in the Middle Jurassic peatlands.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"253 ","pages":"Article 104906"},"PeriodicalIF":4.0,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144230128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tracking climate fluctuations in the North China during the Carboniferous-Permian transition using chemical weathering indices","authors":"Wanli Gao ,&nbsp;Qin Zhang ,&nbsp;Jingtao Zhao ,&nbsp;Qiang Fang ,&nbsp;Wen Liu ,&nbsp;Weiliang Kong ,&nbsp;Wenyu Li ,&nbsp;Hongjie Peng ,&nbsp;Tianquan Qu ,&nbsp;Guangyin Cai ,&nbsp;Jianghai Yang ,&nbsp;Zhen Qiu","doi":"10.1016/j.gloplacha.2025.104900","DOIUrl":"10.1016/j.gloplacha.2025.104900","url":null,"abstract":"<div><div>The Late Paleozoic Ice Age, as the longest-lasting icehouse of the Phanerozoic, includes multiple periods of climate warming and cooling. However, there is still no general consensus on the driving mechanisms of climate fluctuations during the Late Carboniferous-Early Permian transition. Here, we analyze the chemical weathering indices and estimated land surface temperatures of mudstone in the Late Carboniferous-Early Permian strata in the Ordos Basin, North China Craton. It also combines this data with published equivalent weathering data from other regions to track global weathering changes during this key period. Our results exhibit the chemical index of alteration decreased at 301, 299 and 296.5 Ma, suggesting three cooling intervals. These cooling intervals have also been identified and interpreted in the North China Block, Midland Basin, and Gondwana Basins. A less-pronounced cooling events at 301 Ma, while two severe cooling events occurred around 299 Ma and 296.5 Ma. The three cooling intervals played a key role in the Late Paleozoic Ice Age to its icehouse apex in the early Permian. The first (301 Ma) and second (299 Ma) cooling intervals could be caused by the continuous decline in atmospheric CO₂, resulting from the global weathering of worldwide mafic rocks and expansion of paleotropical forests. The third (296.5 Ma) cooling interval could be intensified by rapid chemical weathering of the basalt from the Skagerrak-Centered large igneous province, which rapidly consumed atmospheric CO₂, contributing to the icehouse apex in the early Permian. This study provides new evidence for climate fluctuations during the Carboniferous-Permian transition and offers a better understanding of the driving mechanisms behind these climate changes during the Late Paleozoic Ice Age.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"252 ","pages":"Article 104900"},"PeriodicalIF":4.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144221346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the elevational synchronization in vegetation phenology across Northern Hemisphere mountain ecosystems under global warming","authors":"Chen Yang ,&nbsp;Feng Tian ,&nbsp;Hongxiao Jin ,&nbsp;Rasmus Fensholt ,&nbsp;Luwei Feng ,&nbsp;Torbern Tagesson","doi":"10.1016/j.gloplacha.2025.104903","DOIUrl":"10.1016/j.gloplacha.2025.104903","url":null,"abstract":"<div><div>In recent decades, changes in vegetation phenology have exhibited a tight coupling with global warming. Mountain ecosystems are particularly susceptible to climate change, with high elevations warming faster than lower areas. The inconsistent rate of temperature change across elevations may lead to synchronization of phenological patterns, reducing the differences in phenology timing between high and low elevations. In this study, we employ MODIS data spanning from 2001 to 2022 to analyze the spatiotemporal changes in the start of the growing season (SOS) and the end of the growing season (EOS) as a function of elevation in the Northern Hemisphere mountain ecosystems. We find that 87 % of high-elevation areas experience a later SOS and 71 % have an earlier EOS than low-elevation areas. And our analysis reveals a mixed pattern of elevational gradients for the temporal trends in both SOS and EOS, with approximately half of the study areas showing elevational synchronization, while the other half exhibiting asynchronization. Our findings suggest that temperature is the primary driver of spatial patterns of these elevation gradients, but the complex interplay between temperature and precipitation, combined with diverse responses to these changes for different land cover types, led to the observed mixed patterns of elevational synchronization in phenology. Future climate change is likely to further shift phenological patterns across elevations, affecting the structure and function of mountain ecosystems. Our findings on the variations in vegetation phenology across elevations are crucial for understanding mountain ecosystem responses to climate change.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"252 ","pages":"Article 104903"},"PeriodicalIF":4.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144194834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A strong El Niño significantly affects CH4, CO2, H2O and energy fluxes as well as grain yield in a Thai rainfed rice field","authors":"Arnon Setsungnern ,&nbsp;Choosak Kunuthai ,&nbsp;Amnat Chidthaisong","doi":"10.1016/j.gloplacha.2025.104896","DOIUrl":"10.1016/j.gloplacha.2025.104896","url":null,"abstract":"<div><div>Rainfed rice fields are among the primary rice ecosystems in many Asian countries, including Thailand. High variability in rainfall amount and its distribution under climate change and climate variability, such as El Niño, has made this rice ecosystem highly vulnerable. Here, we report the impacts of El Niño on methane (CH₄), carbon dioxide (CO₂), water (H₂O), energy exchanges, and grain yield in a Thai rainfed lowland rice using the eddy covariance method during 2015–2017. During the rice-growing season, cumulative rainfall and effective rainfall were reduced in the 2015 strong El Niño year by approximately 18.3 % and 19.8 % compared to the neutral years (2016 and 2017), respectively. This resulted in a lower water level (WL) above the paddy surface and required more irrigation water (IWR), especially at the pre-booting stage. A correlation analysis revealed that WL had a strong relationship with CH₄ (<em>r</em> = 0.72) and gross primary production (GPP; r = 0.72) at the pre-booting stage. CH₄ emissions during the cropping season in the 2015 El Niño year were reduced by 56.77 %. In 2015, gross primary production (GPP) during the cropping season was also reduced by 31.5 % and 26.5 % compared to 2016 and 2017, respectively, leading to a decrease in the annual net carbon (C) budget (58.2 g C m⁻²), up to 66.8 % in comparison with 2016 (143.86 g C m⁻²). Moreover, a higher fraction of sensible heat (H) exchange as a higher Bowen ratio along with high net radiation (Rn) in 2015 led to higher evapotranspiration, especially in the post-booting stage. The strong El Niño in 2015 reduced grain yield by 2.8–5.7 %, with less carbon use efficiency (CUE) and water use efficiency (WUE) relative to the non-strong El Niño year. Strong ENSO decreased net C budget and increased net GHG budget during the cropping season. An evaluation and prediction of the amount of rainfall for water supply during strong ENSO phenomena could be an effective measure before rice cultivation in rainfed paddies to prevent crop yield loss from climate oscillations.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":"252 ","pages":"Article 104896"},"PeriodicalIF":4.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}