Environmental Research Letters最新文献

{"title":"Contrasting East Asian climate extremes in 2020 and 2022 tied to zonal flow","authors":"Chao He, Matthew Collins, Tianjun Zhou, Xingwen Jiang, Peili Wu, Nick Dunstone","doi":"10.1088/1748-9326/ad6a72","DOIUrl":"https://doi.org/10.1088/1748-9326/ad6a72","url":null,"abstract":"Subtropical East Asia (STEA) experienced a historic flood in the summer of 2020, and historic drought and heatwaves in the summer of 2022. Previous studies emphasized the role of western Pacific subtropical high (WPSH), but there is a paradox that the contrasting climate extremes over STEA in 2020 and 2022 are both associated with anomalously strong WPSH. Given that local vertical motion has a dominant control on precipitation variability, here we investigate the mechanism for the variability of vertical motion in STEA. In most extratropical regions of the Northern Hemisphere, ascent (descent) motion aligns with southerly (northerly) flow in the troposphere due to the northward tilting isentropic surfaces. However, isentropic surfaces tilt eastwards over STEA in the summer due to the existence of a strong warm center over the Tibetan Plateau (TP). Thus, the ascent motion over the STEA is insensitive to the strength of southerly flow related to the intensity of the WPSH but sensitive to the strength of westerly flow related to the meridional shift of subtropical jet. The notably strong WPSH in 2020 and 2022 increased water vapor transport into STEA but had little impact on atmospheric vertical motion. However, the East Asian subtropical jet displaced southwards (northwards) in the summer of 2020 (2022), leading to anomalous westerly (easterly) flows in the mid-upper troposphere from TP to STEA on the jet’s southern flank, prompting anomalous ascent (descent) motion in STEA that contributed to the flood (drought) conditions in 2020 (2022). Our results highlight the essential role of anomalous zonal flow in generating surface climate extremes over STEA in the summer because of its strong control of vertical motion.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"12 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Balancing livestock production and environmental outcomes in northern Australia’s tropical savanna under global change","authors":"Rebecca K Runting, Darran King, Martin Nolan, Javier Navarro, Raymundo Marcos-Martinez, Jonathan R Rhodes, Lei Gao, Ian Watson, Andrew Ash, April E Reside, Jorge G Álvarez-Romero, Jessie A Wells, Euan G Ritchie, Michalis Hadjikakou, Don A Driscoll, Jeffery D Connor, Jonathan Garber, Brett A Bryan","doi":"10.1088/1748-9326/ad6f2d","DOIUrl":"https://doi.org/10.1088/1748-9326/ad6f2d","url":null,"abstract":"Livestock production is an integral part of the global food system and the livelihoods of local people, but it also raises questions of environmental sustainability due to issues such as greenhouse gas (GHG) emissions, biodiversity decline, land degradation, and water use. Further challenges to extensive livestock systems may arise from changes in climate and the global economy (particularly variation in prices for livestock and carbon). However, significant potential exists for both mitigating these impacts and adapting to change via altering stocking rates, managing fire, and supplementing cattle diets to reduce methane emissions. We developed an integrated, spatio-temporal modelling approach to assess the effectiveness of these options for land management in northern Australia’s tropical savanna under different global change scenarios. Performance was measured against a range of sustainability indicators, including environmental (GHG emissions, biodiversity, water intake, and land condition) and agricultural (profit, beef production) outcomes. Our model shows that maintaining historical stocking rates is not environmentally sustainable due to the accelerated land degradation exacerbated by a changing climate. However, planned early dry season burning substantially reduced emissions, and in our simulations was profitable under all global change scenarios that included a carbon price. Overall, the balance between production and environmental outcomes could be improved by stocking below modelled carrying capacity and implementing fire management. This management scenario was the most profitable (more than double the profit from maintaining historical stocking rates), prevented land degradation, and reduced GHG emissions by 23%. By integrating the cumulative impacts of climate change, external economic drivers, and management actions across a range of sustainability indicators, we show that the future of rangelands in Australia’s savannas has the potential to balance livestock production and environmental outcomes.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"2 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Land surface processes response to warming and wetting trend in Northwest China","authors":"Xin Ma, Aihui Wang, Jianqi Sun","doi":"10.1088/1748-9326/ad70cd","DOIUrl":"https://doi.org/10.1088/1748-9326/ad70cd","url":null,"abstract":"The climate in Northwest China (NWC) has undergone a warming and wetting trend (WWT) since the 1980s, which has attracted considerable attention from the scientific and policy communities. However, the majority of previous studies have focused on overall effects of WWT, and very few have examined how land surface system responds to climate warming or wetting trend, respectively. For this purpose, this study uses the Community Land Model (CLM5) driven by the Chinese Meteorological Forcing Dataset (CMFD) to conduct four modeling experiments: a control experiment (CTRL) and three sensitivity experiments, in which the annual trend of air temperature (NonWarm), precipitation (NonWet), and both (NonWWT) are removed from the CMFD from 1979 to 2018. Compared to CTRL, the land hydrological variables (i.e. soil moisture, runoff and evapotranspiration) show a visible reduction in magnitude, interannual variability, as well as annual trend in NonWet, while they are enhanced in NonWarm. In both NonWarm and NonWet, the magnitude and trend of both net radiation and sensible heat fluxes increase, with a more pronounced change in NonWWT. Further analysis indicates that the land surface processes are more sensitive to wetting trend than to warming trend. Among all land surface hydrological variables and energy variables, runoff and snow cover fraction are the most susceptible to climate change. Overall, the effects of climate change in Ta and Pr on surface hydrological variables are non-linearly offsetting, while the effects on surface energy budgets are non-linearly superimposed. Compared to warming trend, wetting trend plays a larger impact on the variability of land surface processes in NWC.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"3 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global convection-permitting model improves subseasonal forecast of plum rain around Japan","authors":"Jun Gu, Chun Zhao, Mingyue Xu, Jiawang Feng, Gudongze Li, Yongxuan Zhao, Xiaoyu Hao, Junshi Chen, Hong An","doi":"10.1088/1748-9326/ad71e2","DOIUrl":"https://doi.org/10.1088/1748-9326/ad71e2","url":null,"abstract":"In 2020 early summer, a historically severe rainy season struck East Asia, causing extensive damage to life and property. Subseasonal forecast of this event challenges the limits of rainy season predictability. Employing the integrated atmospheric model across scales and the Sunway supercomputer, we conducted ensemble one-month forecasts at global 3 km, variable 4–60 km, and global 60 km resolutions. The global convection-permitting forecast accurately captures the rainband, while other forecasts exhibited northward and weaker shifts due to the northward shifts of the atmospheric rivers over Japan, attributed to intensified Western North Pacific Subtropical High (WNPSH). Further, the double-ITCZ-like tropical rainfall pattern in Western Pacific in global convection-permitting forecast contributes to a more accurate WNPSH and rainband. In contrast, other forecasts show a single-ITCZ-like pattern in Western Pacific, leading to a northward-shifted WNPSH and rainband, advocating the importance of accurately representing tropical convections, as they can significantly affect mid-/high-latitude weather and climate.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"25 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Warming-induced cryosphere changes predict drier Andean eco-regions","authors":"Amen Al-Yaari, Thomas Condom, Fabien Anthelme, Sophie Cauvy-Fraunié, Olivier Dangles, Clémentine Junquas, Pierre Moret, Antoine Rabatel","doi":"10.1088/1748-9326/ad6ea6","DOIUrl":"https://doi.org/10.1088/1748-9326/ad6ea6","url":null,"abstract":"Climate change impacts on humans and ecosystems depend on the intensity, timing, and spatial variability of these changes. While considerable attention has been paid to current and future changes in temperature patterns, comparatively less attention has been devoted to water availability for humans and ecosystems. The aridity index (AI), the ratio of precipitation to potential evapotranspiration, is a common metric used to assess water availability within ecosystems. However, the role of snow in AI calculations within snowy eco-regions is often neglected, resulting in an incomplete understanding of water balance dynamics in these environments. In this study, we estimate aridification under ongoing climate change in Andean eco-regions (AEs), focusing on two horizons: 2050–2060 and 2090–2100. Using monthly TerraClimate data from 2013–2018, we calculated a mean AI for each AE, taking into account the absence of snow (pixels with a snow water equivalent (SWE) < 10 mm/month) and its presence (AI-snow; pixels with a SWE > 10 mm/month). We show that AI allows to differentiate the eco-regions, but that the incorporation of snow in the AI calculation highlights the heterogeneity of aridity conditions within some eco-regions with energy-limited regimes (AI > 1) in the snowy zones and water-limited regimes (AI < 1) elsewhere. Analysis of the CORDEX-SAM regional projections for the periods 2050–2060 and 2090–2100 indicates a general shift towards drier conditions prevailing over wetter conditions in most eco-regions, notably: the Southern Andean Steppe, the Central Andean Wet Puna, the Santa Marta Páramo, and the Peruvian Yungas. The projected reduction in snowfall in CORDEX-SAM, coupled with glacier volume loss, appears to be contributing to the prevalence of aridification across many AEs. These findings highlight potential transitions towards aridification in diverse eco-regions, with repercussions on water availability for humans and ecosystems.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"275 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Attribution of extremes to greenhouse gas-induced changes in regional climate variability, distinct from changes in mean climate","authors":"Armineh Barkhordarian","doi":"10.1088/1748-9326/ad715a","DOIUrl":"https://doi.org/10.1088/1748-9326/ad715a","url":null,"abstract":"Changes in regional climate variability serve as the initial indicators of positive climate feedback mechanisms, which are expected to intensify as greenhouse gas (GHG) emissions unfold. Therefore, it is crucial to examine the extent to which GHG-induced changes in regional climate variability, in isolation from changes in mean climate, contribute to the frequency of extreme weather events. In this study, I build upon the concept of the fraction of attributable risk (FAR) by introducing the fraction of preventable risk (FPR), allowing for the assessment of GHG forcing’s contribution to risk reduction in scenarios of decreasing risk extremes. Results derived from four global climate models indicate that while the predominant factor amplifying the frequency of hot extremes is the mean warming, with a 18-fold increase in probability and an attributable risk fraction of 0.96 to GHG forcing, changes in regional climate variability have already modified the probability of extremes. In South Asia, for instance, the 12-fold increase in hot extremes resulting from mean warming is compounded by an additional ∼3 times, solely attributed to the increased temperature variability. Conversely, during winter in the Arctic, the 10-fold increase in the frequency of hot extremes due to mean warming is offset by a ∼2.5-fold decrease resulting from diminished variability, with a preventable risk fraction of −0.55 to GHG forcing. Concerning heavy-precipitation events, in certain regions, GHG-induced changes in precipitation variability carry greater significance than changes in the mean. For example, in the West African summer monsoon region GHG forcing is amplifying the risk of extreme monsoon precipitation by ∼4 times. This amplified risk of potential flooding arises from increases in both mean precipitation and variability. Separating attribution metrics into mean and variability components offers valuable insights into region-specific mechanisms affecting extreme event frequency.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"331 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heavy grazing reduces the potential for grassland restoration: a global meta-analysis","authors":"Wentao Mi, Weibo Ren, Yuan Chi, Hao Zheng, Ellen Fry, Feng Yuan, Yaling Liu","doi":"10.1088/1748-9326/ad703f","DOIUrl":"https://doi.org/10.1088/1748-9326/ad703f","url":null,"abstract":"Soil seed banks are the main seed reservoirs globally and are critical for the regeneration of grassland plant populations. Grazing often affects the density and diversity of grassland soil seed banks; however, it is not clear how these effects vary on a global scale with grazing intensity, grazing duration, and climatic conditions. Here, we screened 92 independent published articles and performed a meta-analysis of the extracted data. The effects of grazing on four soil seed bank density and diversity indices were analyzed. Four alpha diversity indices, namely Shannon–Wiener, Margalef, Pielou, and Simpson indices, were selected in this study. The Shannon–Wiener index reflects the species complexity of the community. The Margalef index reflects species richness of the seed bank. The Pielou index reflects whether the number of seeds of all species in the seed bank is evenly distributed, and the Simpson’s index reflects the status of dominant plants in the seed bank. We found that grazing significantly decreased the total density of soil seed banks. Perennial plant seed banks were more affected by grazing than annual plant seed banks. Heavy grazing significantly decreased the Margalef index of seed banks, while moderate grazing significantly decreased the Simpson’s alpha diversity index. Long-term grazing (>10 years) had the greatest impact on Simpson’s alpha diversity index, while medium-term grazing (5–10 years) had a significant negative impact on Shannon–Wiener, Margalef, and Pielou indices. In addition, our results show that grazing has a greater effect on seed banks in arid areas than those in temperate areas. Knowledge of climate-specific effects will contribute to understanding the risk of local extinctions in grassland populations and help decision-makers maintain the health of grassland ecosystems.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"63 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental warming affects soil carbon dynamics in boreal and temperate forests: a meta-analysis","authors":"Shan Xu, Jie Ou, Xinxin Qiao, Zhenzhong Zeng, Junjian Wang","doi":"10.1088/1748-9326/ad6fba","DOIUrl":"https://doi.org/10.1088/1748-9326/ad6fba","url":null,"abstract":"Boreal and temperate forests, spanning cold mid- to high-latitude environments and encompassing about 43% of the global forest area, are highly vulnerable to warming. Understanding the response of soil carbon (C) dynamics in these forests to warming is of paramount importance, yet significant uncertainty remains. In this meta-analysis, data from 97 studies across 65 sites were synthesized to investigate the effects of warming on soil C inputs, pools, and outputs in boreal and temperate forests. Our results reveal that warming increased aboveground biomass (by 33%) and litterfall (by 15%), while decreasing litter mass remaining (by 7%), with no significant change observed in fine root biomass. Furthermore, warming led to a 9% increase in soil total respiration and a 15% increase in autotrophic respiration, yet had no discernible impact on soil organic carbon (SOC) content. The methods, magnitude, and duration of warming were found to regulate the responses of soil C dynamics. Buried heater warming elicited the most pronounced effects among warming methods. Additionally, soil total respiration exhibited an acclimation response to warming magnitude and duration, while litter decomposition rates increased and SOC content and microbial biomass C decreased with escalating warming magnitude. Moreover, greater soil respiration response occurred in temperate forests than in boreal forests. These findings underscore the nuanced and context-dependent nature of soil C dynamics in response to experimental warming, providing critical insights for understanding the role of boreal and temperate forests in future climate change mitigation strategies.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"20 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Equity implications of efficient water conservation programs","authors":"Koorosh Azizi, Jesse L Barnes, John M Anderies and Margaret Garcia","doi":"10.1088/1748-9326/ad691a","DOIUrl":"https://doi.org/10.1088/1748-9326/ad691a","url":null,"abstract":"Urban water management is increasingly challenged by the need to balance cost-effectiveness with equity considerations. This study presents a multi-objective approach to water conservation within the Las Vegas valley water district, analyzing a comprehensive dataset of water consumption and socioeconomic indicators across all single-family residences. We assess policy scenarios under two primary objectives: maximizing water savings to enhance economic efficiency and improving water affordability to promote equity. Our analysis reveals that while strategies focused on water savings reduce water use more efficiently, they tend to favor higher-income, predominantly white neighborhoods whereas prioritizing water affordability shifts resources towards lower-income, communities of color. The analysis of intermediate policy scenarios reveals the trade-offs and potential synergies between water savings and affordability. Our findings suggest that local water sustainability can be achieved by allocating resources to both high-demand and socioeconomically disadvantaged households. Highlighting the importance of integrating equity considerations into water management policies, this study provides insights for policymakers in crafting more inclusive and sustainable urban water management practices.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"90 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Warming of mid-latitude North Atlantic Sea surface temperature strengthens the daily variability of winter PM2.5 in eastern China","authors":"Shiyue Zhang, Gang Zeng, Xiaoye Yang and Zhongxian Li","doi":"10.1088/1748-9326/ad6a28","DOIUrl":"https://doi.org/10.1088/1748-9326/ad6a28","url":null,"abstract":"Climate factors, in addition to human activities, are acknowledged to exert a notable influence on the synoptic PM2.5 variations over eastern China in extensive case studies. Based on observed daily PM2.5 concentrations data, this study reveals the enhanced daily variability (DV) of PM2.5 concentrations over eastern China and identifies its association with mid-latitude sea surface temperature anomalies over the North Atlantic. The dominant daily mode of PM2.5 concentrations identified through empirical orthogonal function analysis accounts for 43.75% of the total variance, with its DV experienced a significant enhancement from 1979 to 2019. The identified enhancement is attributed to the intensified wave train propagation along the mid-latitudes on a time scale of 10–30 d. The eastward propagation of the identified wave train can expose eastern China to recurrent influences of cyclonic and anticyclonic anomalies, resulting in an initial increase and subsequent decrease in PM2.5 concentrations. Statistical analysis and dynamic diagnostics show that the warming of the mid-latitude North Atlantic Ocean enhances the wave train at its source through the local energy exchange, and ultimately leads to an increased DV of PM2.5 concentrations.","PeriodicalId":11747,"journal":{"name":"Environmental Research Letters","volume":"57 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141936911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}