Journal of Climate最新文献_第2页

MJO structure-propagation nexus and impacts of background mean states in CMIP6 models MJO 结构-传播关系以及 CMIP6 模型中背景平均状态的影响

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-11 DOI: 10.1175/jcli-d-23-0348.1

Yuhang Xiang, Juan Li, Bin Wang, Libin Ma, Zhiwei Zhu

{"title":"MJO structure-propagation nexus and impacts of background mean states in CMIP6 models","authors":"Yuhang Xiang, Juan Li, Bin Wang, Libin Ma, Zhiwei Zhu","doi":"10.1175/jcli-d-23-0348.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0348.1","url":null,"abstract":"Abstract Eastward propagation is an essential feature of the Madden-Julian Oscillation (MJO). Yet, it remains a challenge to realistically simulate it by global climate system models, and the reasons are not fully understood. This study evaluates the capability of 20 Coupled Model Intercomparison Project Phase 6 (CMIP6) models in simulating MJO’s eastward propagation and its intrinsic links with the dynamic/thermodynamic structures and the background mean states, aiming at better understanding the sources of the simulation errors. The metrics to evaluate the MJO internal dynamics consists of six parameters: (1) the east-west asymmetry in the low-level circulation, (2) the boundary layer moisture convergence propagation, (3) the vertical tilt of equivalent potential temperature or moist static energy, the vertical structures of (4) diabatic heating and (5) available potential energy generation, and (6) upper-level diabatic heating and divergence. We also gauge the performance of three MJO-related background mean-state fields, including precipitation, sea surface temperature, and low-level moist static energy. It is argued that these parameters are relevant internal and external factors that could affect MJO eastward propagation. We find that the boundary layer moisture convergence is most tightly coupled with the eastward propagation of MJO and controls the pre-moistening, destabilization, and the leading low-level diabatic heating and available potential energy generation. The CMIP6 models exhibit significant improvements against CMIP5 models in simulating MJO dynamic/thermodynamic structures and the mean states. The diagnostics in this study could help to identify the possible processes related to CMIP6 models’ shortcomings and shed light on how to improve simulation of MJO eastward propagation in the future.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"43 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139422423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Uncertainties in the projection of dynamic sea level in CMIP6 and FGOALS-g3 large ensemble CMIP6 和 FGOALS-g3 大集合中动态海平面预测的不确定性

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-09 DOI: 10.1175/jcli-d-23-0272.1

Chenyang Jin, Hailong Liu, Pengfei Lin, Yiwen Li

{"title":"Uncertainties in the projection of dynamic sea level in CMIP6 and FGOALS-g3 large ensemble","authors":"Chenyang Jin, Hailong Liu, Pengfei Lin, Yiwen Li","doi":"10.1175/jcli-d-23-0272.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0272.1","url":null,"abstract":"Abstract Decision-makers need reliable projections of future sea level change for risk assessment. Untangling the sources of uncertainty in sea level projections will help narrow the projection uncertainty. Here, we separate and quantify the contributions of internal variability, intermodel uncertainty, and scenario uncertainty to the ensemble spread of dynamic sea level (DSL) at both the basin and regional scales using Coupled Model Intercomparison Project Phase 6 (CMIP6) and FGOALS-g3 large ensemble (LEN) data. For basin-mean DSL projections, intermodel uncertainty is the dominant contributor (>55%) in the near- (2021-2040), mid- (2041-2060), and long-term (2081-2100) relative to the climatology of 1995-2014. Internal variability is of secondary importance in the near- and mid-term until scenario uncertainty exceeds it in all basin except the Indian Ocean in the long-term. For regional-scale DSL projections, internal variability is the dominant contributor (60~100%) in the Pacific Ocean, Indian Ocean and western boundary of the Atlantic Ocean, while intermodel uncertainty is more important in other regions in the near-term. The contribution of internal variability (intermodel uncertainty) decreases (increases) in most regions from mid-term to long-term. Scenario uncertainty becomes important after emerging in the Southern, Pacific, and Atlantic oceans. The signal-to-noise (S/N) ratio maps for regional DSL projections show that anthropogenic DSL signals can only emerge from a few regions. Assuming that model differences are eliminated, the perfect CMIP6 ensemble can capture more anthropogenic regional DSL signals in advance. These findings will help establish future constraints on DSL projections and further improve the next generation of climate models.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"2 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139415120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimating time-dependent structures in a multi-variate causality for land-atmosphere interactions 估算陆地-大气相互作用多变量因果关系中的时间相关结构

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-09 DOI: 10.1175/jcli-d-23-0207.1

Feihong Zhou, Daniel Fiifi Tawia Hagan, Guojie Wang, X. San Liang, Shijie Li, Yuhao Shao, Emmanuel Yeboah, Xikun Wei

{"title":"Estimating time-dependent structures in a multi-variate causality for land-atmosphere interactions","authors":"Feihong Zhou, Daniel Fiifi Tawia Hagan, Guojie Wang, X. San Liang, Shijie Li, Yuhao Shao, Emmanuel Yeboah, Xikun Wei","doi":"10.1175/jcli-d-23-0207.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0207.1","url":null,"abstract":"Abstract The land surface and atmosphere interaction forms an integral part of the climate system. However, this intricate relationship involves many complicated interactions and feedback effects between multiple variables. As a result, relying solely on traditional linear regression analysis and correlation analysis to distinguish between multi-variate complex ‘driver-response’ relations can be challenging, since they do not have the needed asymmetry to establish causality. The Liang-Kleeman (LK) information flow theory provides a strict non-parametric causality measurement for identifying the causality between any given time series, and its recent extension from bivariate to multi-variate form provides a powerful tool for causal inference in complex multi-variate systems. However, the multi-variate LK information flow also assumes stationarity in time and requires a sufficiently long time series to ensure statistical sufficiency. To remedy this challenge, we rely on the square root Kalman filter to estimate the time-varying form of the multi-variate LK information flow causality. The results from theoretical and real-world applications show that the new algorithm provides a valuable tool for characterizing time-varying causal relationships in land-atmosphere interactions, even when the time series are short and highly correlated.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"117 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139415060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aridification and its impacts on terrestrial hydrology and ecosystems over a comprehensive transition zone in China 干旱化及其对中国综合过渡带陆地水文和生态系统的影响

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-09 DOI: 10.1175/jcli-d-23-0203.1

Zhuoyi Li, Qing Yang, Zhuguo Ma, Peili Wu, Yawen Duan, Mingxing Li, Ziyan Zheng

{"title":"Aridification and its impacts on terrestrial hydrology and ecosystems over a comprehensive transition zone in China","authors":"Zhuoyi Li, Qing Yang, Zhuguo Ma, Peili Wu, Yawen Duan, Mingxing Li, Ziyan Zheng","doi":"10.1175/jcli-d-23-0203.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0203.1","url":null,"abstract":"Abstract In China, the topography, climate, ecology, hydrology and human environment vary greatly from southeast to northwest, and a typical natural and social environmental transition zone (namely comprehensive transition zone) exists near the “Hu Huanyong line” that is a famous demographic dividing line in China, known as the Hu zone. Dry-wet climate changes in the Hu zone can have a significant impact on terrestrial ecosystems and hydrological conditions, ultimately affecting human-land relations. However, there is still a lack of clear understanding of environmental changes in the context of climate change in the Hu zone. Here, a quantitative analysis of climate change and its impact on terrestrial hydrology and ecosystems from 1951 to 2020 is presented. The results showed that there exists a significant drying trend in the Hu zone and a dramatic decrease in terrestrial water storage (TWS), indicating that the environment has become worse. Conversely, from the perspective of significant greening, the environment has improved. This contradiction is mainly due to climate change dominating the depletion of TWS, while the increase in vegetation greenness is more driven by human activities including agricultural management and ecological restoration, offsetting to some extent the negative impact of water scarcity on vegetation growth.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"48 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139415103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A potential seasonal predictor for summer rainfall over eastern China: Spring Eurasian snowmelt 中国东部夏季降雨的潜在季节预测因子：春季欧亚融雪

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-08 DOI: 10.1175/jcli-d-23-0428.1

Bei Xu, Gen Li

{"title":"A potential seasonal predictor for summer rainfall over eastern China: Spring Eurasian snowmelt","authors":"Bei Xu, Gen Li","doi":"10.1175/jcli-d-23-0428.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0428.1","url":null,"abstract":"Abstract The hydrological effect of snow over Eurasia is important for regulating regional and global climate through affecting land-atmosphere energy exchange. Based on the observational and reanalysis datasets, this study investigates the effect of spring Eurasian snowmelt on the following summer rainfall over eastern China during the period of 1979–2018. The results show that a substantial meridional dipole pattern of summer rainfall anomalies over eastern China is closely associated with the preceding spring snowmelt anomalies over Eurasia, especially over the remote Siberia. Excessive snowmelt anomalies over Siberia in spring could result in a wetter local soil condition from spring until the following summer, thereby increasing latent heat fluxes and reducing local surface temperature, and vice versa. Then, the anomalous summer surface cooling over Siberia increases the meridional gradient of temperature between the Eurasian mid- latitudes and high-latitudes, which intensifies the Eurasian atmospheric baroclinicity and motivates the eddy- induced geopotential height responses along with the significant wave propagations spreading from the Eurasian high- latitudes to Lake Baikal. As a result, excessive spring snowmelt anomalies over Siberia tend to be accompanied with an anomalous anticyclone circulation to the east of Lake Baikal and an anomalous cyclonic circulation over southeastern China in the following summer. This could lead to a meridional dipole pattern of summer rainfall anomalies over eastern China, with deficient rainfall over northern China and slightly excessive rainfall over southern China. The present findings highlight the lagged effect of spring Eurasian snowmelt on summer climate over eastern China, with implications for the regional seasonal climate prediction.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"24 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139415107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Combined Impacts of Southern Annular Mode and Zonal Wave Three on Antarctic Sea Ice Variability 南环流模式和 "日冕波三 "对南极海冰变化的综合影响

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-08 DOI: 10.1175/jcli-d-23-0516.1

Michael D Eabry, Rishav Goyal, Andréa S Taschetto, Will Hobbs, Alex Sen Gupta

{"title":"Combined Impacts of Southern Annular Mode and Zonal Wave Three on Antarctic Sea Ice Variability","authors":"Michael D Eabry, Rishav Goyal, Andréa S Taschetto, Will Hobbs, Alex Sen Gupta","doi":"10.1175/jcli-d-23-0516.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0516.1","url":null,"abstract":"Abstract Large-scale modes of atmospheric variability in the southern mid-latitudes can influence Antarctic sea ice concentrations (SIC) via diverse processes. For instance, variability in both the Southern Annular Mode (SAM) and Zonal Wave Three (ZW3) have been linked to the abrupt 2015/16 sea ice decline. While SIC responses to each of SAM and ZW3 have been examined previously, their interaction and synchronous impact on Antarctic sea ice has not. Here, we investigate SAM/ZW3 interactions and their associated combined impacts on Antarctic sea ice using a 1,200-year simulation from a state-of-the-art climate model. Our results suggest that zonal wind anomalies associated with SAM drive SIC anomalies in the marginal ice-zone via advection of ice normal to the ice-edge and Ekman drift. In contrast, meridional wind anomalies associated with ZW3 can have opposing dynamic and thermodynamic effects on SIC. Both SAM- and ZW3-related SIC anomalies propagate eastward, likely by the Antarctic Circumpolar Current. The interaction of SAM and ZW3 leads to interesting regional SIC responses. During negative SAM, ZW3-associated meridional wind anomalies across western Antarctica are closer to the ice-edge and have a stronger impact on sea ice overall. ZW3 phase affects meridional wind anomalies across the whole ice-edge, whereas it affects SIC anomalies mainly over western Antarctica. In parts of eastern Antarctica, SIC anomalies are less sensitive to ZW3 phase, but are sensitive to SAM, particularly in locations where the ice-edge has a prominent angle relative to the SAM-related zonal wind anomalies.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"86 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139422429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A framework for assessing the drivers and impacts of drought events: the contemporary drought in the western and central United States 评估干旱事件的驱动因素和影响的框架：美国西部和中部的当代干旱

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-08 DOI: 10.1175/jcli-d-23-0473.1

Lucas Ellison, Sloan Coats

{"title":"A framework for assessing the drivers and impacts of drought events: the contemporary drought in the western and central United States","authors":"Lucas Ellison, Sloan Coats","doi":"10.1175/jcli-d-23-0473.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0473.1","url":null,"abstract":"Abstract We develop a framework for assessing the drivers and impacts of droughts, built upon a Markov Random Field and machine learning-based drought identification algorithm that operates simultaneously in space and time. The method uses a precipitation threshold for drought, while considering the drought state of neighboring grid points and identifies contiguous and distinct droughts that propagate through space and time. Importantly, this method can identify droughts of any scale, from a single grid point to those encompassing many thousands. We apply it to North American precipitation from observations and a multi-model ensemble of 67 historical simulations to produce a repository of 25,156 identified droughts. The framework uses an observed drought for comparison, and we choose the 2011-2014 drought in the western and central United States, which is among the most severe and persistent in recorded history. As the spatiotemporal characteristics of the simulated droughts become more like the observed drought, we quantify if their local-scale impacts (evaporation, leaf area index, soil moisture, and runoff) and large-scale drivers (atmospheric circulation, sea surface temperature, and modes of climate variability) become predictable. Our findings suggest that ecological impacts are not predictable even when simulated droughts closely match the spatiotemporal characteristics of the observed drought. The drought drivers are also not predictable, with similar droughts occurring under a range of atmosphere-ocean conditions. These results suggest that the drivers and impacts of even the most persistent and severe droughts have limited predictability, although additional work is needed to quantify the role of structural uncertainty and better understand the real-world applicability of climate model-based results.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"39 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139423972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Long-Term Variations and its Driving Factors of the TOA Albedo over the Loess Plateau 黄土高原 TOA 反照率的长期变化及其驱动因素

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-05 DOI: 10.1175/jcli-d-23-0380.1

Qianru Wang, Shuhua Zhang

{"title":"Long-Term Variations and its Driving Factors of the TOA Albedo over the Loess Plateau","authors":"Qianru Wang, Shuhua Zhang","doi":"10.1175/jcli-d-23-0380.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0380.1","url":null,"abstract":"Abstract Solar radiation balances significantly affect the Earth’s surface energy balance and climate change. Studying top-of-atmosphere (TOA) albedo changes is of great significance for understanding Earth’s energy budget and atmospheric circulation. The Loess Plateau (LP), located in the middle reaches of the Yellow River in China, is one of the most severely eroded areas in the world. In this paper, long-term remote sensing data were used to analyze the changes in the TOA albedo in the LP from 1982 to 2016. The results showed that the TOA albedo, its atmospheric contribution (AC), and surface contribution (SC) exhibited decreasing trends: −0.0012/a, −0.0010/a, and −0.0003/a. The spatial pattern of the TOA albedo was similar to AC, which indicates that AC dominates the change in the TOA albedo. We detected driving factors for AC and SC, and found that the cloud fraction (CF) was the main driving factor of the AC, whereas the soil moisture (SM) dominated the SC. The driving factors of two typical regions with a significantly decreasing trend in the TOA albedo were also detected. The Mu Us Desert, where vegetation improved significantly, showed a decreasing trend in the TOA albedo, and we found that NDVI was the main driving factor for the change in the SC of the TOA albedo. However, the Eastern Qilian Mountains, where snow cover decreased in recent years, also showed a significant decreasing trend in the TOA albedo; the SC here was mainly driven by the changes in snow cover days (SCD). These results indicate that changes in the surface environment alter the radiation balance.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"34 7 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139376253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seasonal reversal of ENSO impacts on SST in the East China Sea-Kuroshio region 厄尔尼诺/南方涛动对东海-黑潮地区海温影响的季节性逆转

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-05 DOI: 10.1175/jcli-d-23-0556.1

Yuwei Xie, Wenjun Zhang, Suqiong Hu, Feng Jiang

{"title":"Seasonal reversal of ENSO impacts on SST in the East China Sea-Kuroshio region","authors":"Yuwei Xie, Wenjun Zhang, Suqiong Hu, Feng Jiang","doi":"10.1175/jcli-d-23-0556.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0556.1","url":null,"abstract":"Abstract Sea surface temperature (SST) variability in the East China Sea-Kuroshio (EK) region has important implications for the surrounding weather, climate, and marine ecology. The year-to-year variations of the EK SST are expectedly linked to the El Niño-Southern Oscillation (ENSO), the predominant predictability source of seasonal-to-interannual climate variability. Surprisingly, no significant SST signal is observed in the EK region when focusing on the ENSO autumn-winter season with the persistent and pronounced SST anomalies in the tropical Pacific. We find that a remarkable seasonal reversal appears in the ENSO-EK SST connection, shifting from a negative relationship in autumn (Aug(0)-Oct(0)) to a positive relationship in winter (Dec(0)-Feb(1)). This reversal is mainly attributed to the seasonally varying ENSO-associated Western North Pacific (WNP) atmospheric circulation patterns. During ENSO autumns, the anomalous WNP anticyclone is confined south of 20°N, which is accompanied with cyclonic circulation anomalies in the EK region. The associated anomalous northerly wind tends to enhance the background northerly wind, thereby facilitating the local SST cooling mainly via the wind-evaporation-SST effect. In the subsequent winter, the ENSO-related WNP anticyclonic anomalies intensify and extend toward the EK region. Consequently, the weakened background northerly wind induced by southerly wind anomalies, leads to the increase of downward latent and sensible heat flux in the EK region, fostering the local SST warming. The observed seasonal reversal of ENSO impacts can be evidenced by the tropical Pacific pacemaker experiments, emphasizing the importance of seasonally modulated ENSO teleconnection and holding implications for the local SST climate prediction.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"61 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139376214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Atmospheric rivers are responsible for cyclicity in Sierra Nevada precipitation 大气河流是内华达山脉降水周期性的原因

IF 4.9 2区地球科学

Journal of Climate Pub Date : 2024-01-05 DOI: 10.1175/jcli-d-23-0421.1

A. P. Williams, K. J. Anchukaitis, A.M. Varuolo-Clarke

{"title":"Atmospheric rivers are responsible for cyclicity in Sierra Nevada precipitation","authors":"A. P. Williams, K. J. Anchukaitis, A.M. Varuolo-Clarke","doi":"10.1175/jcli-d-23-0421.1","DOIUrl":"https://doi.org/10.1175/jcli-d-23-0421.1","url":null,"abstract":"Abstract Cool-season (November–March) precipitation contributes critically to California’s water resources and flood risk. In the Sierra Nevada, approximately half of cool-season precipitation is derived from a small proportion of storms classified as atmospheric rivers (ARs). The frequency and intensity of ARs are highly variable from year to year and unreliable climate teleconnections limit forecasting. However, previous research provides intriguing evidence of cycles with biennial (2.2-year) and decadal (10–20-year) periodicities in Sierra Nevada cool-season precipitation, suggesting it is not purely stochastic. To identify the source of this cyclicity, we decompose daily precipitation records (1949–2022) into contributions from ARs vs non-ARs, as well as into variations in frequency and intensity. We find that the biennial and decadal spectral peaks in Sierra Nevada precipitation totals are entirely due to precipitation delivered by ARs, and primarily due to variations in the frequency of days with AR precipitation. While total non-AR precipitation correlates with sea-surface temperature (SST) and atmospheric pressure patterns associated with the El Niño-Southern Oscillation, AR precipitation shows no consistent remote teleconnections at any periodicity. Supporting this finding, atmospheric simulations forced by observed SSTs do not reproduce the biennial or decadal precipitation variations identified in observations. These results, combined with the lack of long-term stable cycles in previously published tree-ring reconstructions, suggest that the observed biennial and decadal quasi-cyclicity in Sierra Nevada precipitation is unreliable as a forecasting tool.","PeriodicalId":15472,"journal":{"name":"Journal of Climate","volume":"4 1","pages":""},"PeriodicalIF":4.9,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139376254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0