Atmospheric Science Letters最新文献_第10页

Towards a more comprehensive assessment of the intensity of historical European heat waves (1979–2019) 对欧洲历史热浪强度(1979-2019)进行更全面的评估

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-07-04 DOI: 10.1002/asl.1120

Florian N. Becker, Andreas H. Fink, Peter Bissolli, Joaquim G. Pinto

{"title":"Towards a more comprehensive assessment of the intensity of historical European heat waves (1979–2019)","authors":"Florian N. Becker, Andreas H. Fink, Peter Bissolli, Joaquim G. Pinto","doi":"10.1002/asl.1120","DOIUrl":"10.1002/asl.1120","url":null,"abstract":"Europe has been affected by record-breaking heat waves in recent decades. Using station data and a gridded reanalysis as input, four commonly used heat wave indices, the heat wave magnitude index daily (HWMId), excess heat factor (EHF), wet-bulb globe temperature (WBGT) and universal thermal climate index (UTCI), are computed. The extremeness of historical European heat waves between 1979 and 2019 using the four indices and different metrics is ranked. A normalisation to enable the comparison between the four indices is introduced. Additionally, a method to quantify the influence of the input parameters on heat wave magnitude is introduced. The spatio-temporal behaviour of heat waves is assessed by spatial–temporal tracking. The areal extent, large-scale intensity and duration are visualized using bubble plots. As expected, temperature explains the largest variance in all indices, but humidity is nearly as important in WBGT and wind speed plays a substantial role in UTCI. While the 2010 Russian heat wave is by far the most extreme event in duration and intensity in all normalized indices, the 2018 heat wave was comparable in size for EHF, WBGT and UTCI. Interestingly, the well-known 2003 central European heat wave was only the fifth and tenth strongest in cumulative intensity in WBGT and UTCI, respectively. The June and July 2019 heat waves were very intense, but short-lived, thus not belonging to the top heat waves in Europe when duration and areal extent are taken into account. Overall, the proposed normalized indices and the multi-metric assessment of large-scale heat waves allow for a more robust description of their extremeness and will be helpful to assess heat waves worldwide and in climate projections.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1120","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41613887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

The diurnal cycle of the lightning potential index over the Mexican tropical continental region during tropical cyclone Bud 热带气旋巴德期间墨西哥热带大陆地区闪电势指数的日循环

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-06-24 DOI: 10.1002/asl.1119

Jorge Clouthier-Lopez, Ricardo Barrón-Fernández, David Alberto Salas-de-León

{"title":"The diurnal cycle of the lightning potential index over the Mexican tropical continental region during tropical cyclone Bud","authors":"Jorge Clouthier-Lopez, Ricardo Barrón-Fernández, David Alberto Salas-de-León","doi":"10.1002/asl.1119","DOIUrl":"10.1002/asl.1119","url":null,"abstract":"Atmospheric processes over the Mexican continental territory can be influenced by the occurrence of tropical cyclones (TCs) over the adjacent oceans. Furthermore, the Mexican territory is characterized by the presence of diurnal cycles of lightning. The Lightning Potential Index (LPI), that is a measure of the potential for charge generation and separation that leads to lightning production in convective storms, was assessed for the diurnal variability of lightning that exhibited a strong diurnal cycle over the Mexican continental territory when TC Bud was over the adjacent eastern Pacific Ocean. The assessment, from 0000 UTC 10 June to 2000 UTC 15 June 2018, used the Weather Research and Forecasting (WRF) model with a new hybrid terrain-following sigma-pressure vertical coordinate. Two ensembles with various cumulus and microphysical parameterizations were performed with a grid spacing of 2 km. In one ensemble, sea surface temperature (SST) was prescribed from the Real-time global (RTG) SST analysis product and allowed to evolve interactively with the modeled atmosphere. Then, all the ensemble members were compared against available observations from the World Wide Lightning Location Network (WWLLN) to evaluate which model configurations perform best. It is not known if the LPI is capable of reproducing diurnal cycles of lightning over tropical regions; and the results allow gaining an understanding of the LPI when it reproduces the observed diurnal variability of lightning over land. The ensemble members that had better performances were those that included the prescribed SST.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1119","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42695758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

The role of atmospheric fronts in austral winter precipitation changes across Australia 大气锋面在澳大利亚南部冬季降水变化中的作用

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-06-24 DOI: 10.1002/asl.1117

Lindsay Lawrence, Rhys Parfitt, Caroline C. Ummenhofer

{"title":"The role of atmospheric fronts in austral winter precipitation changes across Australia","authors":"Lindsay Lawrence, Rhys Parfitt, Caroline C. Ummenhofer","doi":"10.1002/asl.1117","DOIUrl":"10.1002/asl.1117","url":null,"abstract":"Over the past few decades, Southeast Australia has experienced severe regional climatic events and some of the most extreme droughts on record, linked in part to influences from both the El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). In this article, the extent to which austral winter rainfall anomalies, in years leading into co-occurring ENSO and IOD events, are communicated specifically through variations in atmospheric fronts is quantified. The most extreme wet (dry) conditions occur in winters characterized by sea surface temperature anomaly patterns exhibiting features of La Niña-Negative IOD (El Niño-Positive IOD). It is found that most of these precipitation anomalies are related to changes in the precipitation associated with the passing of atmospheric fronts specifically. Although there is some suggestion that there are accompanying changes in the frequency of atmospheric fronts, the response appears to be dominated by changes in the amount of precipitation per individual atmospheric front. In addition, the distribution in the dynamic strength of individual atmospheric fronts remains relatively unchanged.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 10","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1117","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43895345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Long-term changes in spatially coherent extreme precipitation systems over Central India 印度中部空间相干极端降水系统的长期变化

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-06-22 DOI: 10.1002/asl.1118

Anu Gupta, Hiroshi G. Takahashi

{"title":"Long-term changes in spatially coherent extreme precipitation systems over Central India","authors":"Anu Gupta, Hiroshi G. Takahashi","doi":"10.1002/asl.1118","DOIUrl":"10.1002/asl.1118","url":null,"abstract":"The present study examined extreme rainfall events (EREs) in central India during the summer monsoon season, focusing on their spatial characteristics. A station-based gridded and a station-satellite-blended dataset was used to examine long-term and recent variations in precipitation characteristics for 50 years (1951–2000) and 38 years (1981–2018), respectively. A precipitation system approach (PSA) was applied to identify the ERE precipitation systems and categorized spatial sizes of ERE systems into three categories: sporadic, intermediate, and massive ERE precipitation systems. Conventionally, the ERE frequency is equal to the total number of ERE grids, whereas PSA counts ERE systems. The sporadic precipitation grid contributes 42% of all the ERE grids, and sporadic EREs frequency increases in the long-term. The long-term trend of intermediate and massive EREs does not increase and quite sharply increases, respectively, and these EREs are also intensifying. Recent 38 years have shown a reverse in the trends of ERE characteristics, the frequency and intensity of intermediate and massive EREs have decreased, whereas the massive ERE systems are broadening.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 11","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1118","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42133709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Separating the shortwave and longwave components of greenhouse gas radiative forcing 分离温室气体辐射强迫的短波和长波分量

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-06-13 DOI: 10.1002/asl.1116

Keith P. Shine, Rachael E. Byrom, Ramiro Checa-Garcia

{"title":"Separating the shortwave and longwave components of greenhouse gas radiative forcing","authors":"Keith P. Shine, Rachael E. Byrom, Ramiro Checa-Garcia","doi":"10.1002/asl.1116","DOIUrl":"10.1002/asl.1116","url":null,"abstract":"Many important greenhouse gases (including water vapour, carbon dioxide, methane and ozone) absorb solar radiation. When gas concentrations change, this absorption exerts a radiative forcing that modifies the thermal infrared (‘longwave’) radiative forcing which is predominant for most gases (ozone being a major exception). The nature of the solar forcing differs from the longwave forcing in several ways. For example, the sign of the instantaneous solar forcing can differ between the tropopause and top-of-atmosphere, and the sign can differ between gases. In addition, a significant part of the solar forcing can be manifested in the longwave, following stratospheric temperature adjustment, which can counteract or enhance the instantaneous solar forcing. Here the nature of solar forcing is examined via a mixture of idealised and more realistic calculations, which consider the effect of perturbations in carbon dioxide, methane and ozone. An apparent contradiction in the sign of the solar forcing of carbon dioxide is resolved; it is shown to be negative, reducing the net carbon dioxide forcing by about 2.3%. The relevance of this work to the effective radiative forcing concept is also discussed.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 10","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1116","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49643915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

A new subseasonal atmospheric teleconnection bridging tropical deep convection over the western North Pacific and Antarctic weather 一个新的亚季节大气遥相关桥接北太平洋西部和南极天气上的热带深对流

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-06-09 DOI: 10.1002/asl.1115

Yuexiang Sun, Benkui Tan

{"title":"A new subseasonal atmospheric teleconnection bridging tropical deep convection over the western North Pacific and Antarctic weather","authors":"Yuexiang Sun, Benkui Tan","doi":"10.1002/asl.1115","DOIUrl":"10.1002/asl.1115","url":null,"abstract":"Previous studies indicate that convective heating variability of the western North Pacific summer monsoon (WNPSM) influences strongly weather and climate over East Asia. Based on daily reanalysis data and interpolated outgoing longwave radiation (OLR) data, this study demonstrates that the WNPSM convection can also cause severe weather events remotely over the Antarctic through the exciting of the Australia-South Pacific-Atlantic wave train (ASPA pattern). Surface air temperature (SAT) rises over the Ross Sea-Mawson-Dumont d'Urville Seas sector and over the Weddell Sea, while the SAT drops over the Amundsen–Bellingshausen Seas. Concurrently, sea ice concentration (SIC) is reduced over the Ross Sea and enhanced over the Amundsen–Bellingshausen Seas. The result suggests that the newly found ASPA pattern may serve as an important bridge linking the WNPSM convection and the weather over the Antarctic region.The dynamics of ASPA's formation and propagation are also investigated comprehensively. Day-to-day energy budget analysis suggests that after its initiation by WNPSM convection, the ASPA pattern is driven by the baroclinic energy conversion from the climatological flow and nonlinear term. The barotropic energy conversion from the climatological flow contributes to positive KE tendency before day +1 and negative KE tendency after day +1. It is therefore extremely important to improve the representations of the climatological-mean sea ice and jet stream, wave-mean flow interaction and wave-wave interaction in the mid- and high-latitudes of the Southern Hemisphere, as well as the convection over the WNPSM region of the Northern Hemisphere in numerical model for a better weather prediction for the Antarctic.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 10","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1115","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48416619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characteristics of newly formed mesoscale convective systems during the abnormal precipitation over the Yangtze River basin from June to July, 2020 2020年6 - 7月长江流域异常降水中尺度对流系统新形成特征

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-06-07 DOI: 10.1002/asl.1114

Xiuping Yao, Honghua Zhang, Jiali Ma, Dawei Shi, Weijian Wang, Guichen Wang

{"title":"Characteristics of newly formed mesoscale convective systems during the abnormal precipitation over the Yangtze River basin from June to July, 2020","authors":"Xiuping Yao, Honghua Zhang, Jiali Ma, Dawei Shi, Weijian Wang, Guichen Wang","doi":"10.1002/asl.1114","DOIUrl":"10.1002/asl.1114","url":null,"abstract":"A 62-day “extremely violent Meiyu” occurred in the Yangtze River basin from June to July in 2020, and its abnormal precipitation caused serious losses to the social economy. In this paper, the characteristics of newly formed mesoscale convective systems (MCSs) and the environmental conditions affecting the MCS formation during this abnormal precipitation event are investigated based on hourly datasets, including the temperature of brightness blackbody (TBB) data derived from the FY-2F geostationary meteorological satellite, and the three-source merged precipitation products from China Meteorological Administration. The results show that there were 31,778 times of short-duration heavy precipitation (hourly precipitation exceeding 20 mm) occurred in the Yangtze River basin from June to July in 2020. The 69.3% of short-duration heavy precipitation (hourly precipitation exceeding 20 mm) are closely related to the MCSs. The increase of newly formed MCSs leaded to more short-duration heavy precipitation. The abnormal precipitation in the Yangtze River basin from June to July is mainly caused by elongated MCSs with an average lifetime of 6 h. The number of the newly formed MCSs presents obvious diurnal variations, with the most frequent at 20:00 (Beijing Time, the same below). The newly formed MCSs are prone to appear near the Yangtze–Huaihe shear line, and the magnitude of southerly wind at 500 hPa determines the distance between the MCSs and the shear line. The enhancement of vorticity advection at 500 hPa and water vapor convergence are conducive to the MCS formation. The weakening of low-level jet corresponds to the increase of newborn MCS.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 10","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1114","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42204708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Impact of aerosol concentration on elevation-dependent warming pattern in the mountains of Nepal 气溶胶浓度对尼泊尔山区海拔依赖性变暖格局的影响

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-05-17 DOI: 10.1002/asl.1101

Yam Prasad Dhital, Jianwu Tang, Ashok Kumar Pokharel, Qiuhong Tang, Mukesh Rai

引用次数: 3

Importance of ocean prediction for heavy rainfall prediction over Japan in July 2020 海洋预报对2020年7月日本强降雨预报的重要性

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-05-16 DOI: 10.1002/asl.1099

Yuya Baba

{"title":"Importance of ocean prediction for heavy rainfall prediction over Japan in July 2020","authors":"Yuya Baba","doi":"10.1002/asl.1099","DOIUrl":"10.1002/asl.1099","url":null,"abstract":"Hindcast experiments were performed for heavy rainfall events over Japan in July 2020 using a regional atmospheric model and a regional coupled model to examine the importance of ocean prediction for predicting heavy rainfall events. Both models were able to predict the first peak of accumulated rainfall over western Japan occurring in the first half of July. However, only the coupled model predicted the second peak that occurred in the second half of July. Sea level pressure (SLP) and low-level moisture inflow originating from an existing atmospheric river (AR) were found to differ in each model. In the regional atmospheric model, the error associated with the inaccurate low-level moisture inflow grew with rising excessive latent heat flux, which enhanced convection and resulted in incorrect SLP patterns. This trend seems to be enhanced by having a prescribed sea surface temperature (SST), which affects the surface heat flux. When ocean conditions are predicted as in the coupled model, such error growth is suppressed by changes in SST that adjust surface heat flux, and it leads to generation of the correct SLP patterns. With correct SLP especially for Pacific high in this case, favorable conditions for inflow from the AR can also be predicted, thus making it possible to predict the heavy rainfall. In conclusion, considering the atmospheric feedback on SST, ocean prediction can improve the predictability of heavy rainfall over Japan, the conditions for which are influenced by the nearby AR. Ocean prediction may therefore extend the range of weather forecasting.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45699276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Hourly rolling correction of precipitation forecast via convolutional and long short-term memory networks 基于卷积和长短期记忆网络的降水预报每小时滚动修正

IF 3 4区地球科学

Atmospheric Science Letters Pub Date : 2022-05-11 DOI: 10.1002/asl.1100

Ruyi Yang, Jianli Mu, Shudong Wang, Lijuan Wang

{"title":"Hourly rolling correction of precipitation forecast via convolutional and long short-term memory networks","authors":"Ruyi Yang, Jianli Mu, Shudong Wang, Lijuan Wang","doi":"10.1002/asl.1100","DOIUrl":"10.1002/asl.1100","url":null,"abstract":"In order to improve precipitation forecast from GRAPES_Meso V4.0 in China, we propose a 1–6-h rolling correction solution, based on infrared (IR) channels from geostationary meteorological satellite and surface observation data. In particular, we design a deep learning extrapolation model to predict the evolution of cloud clusters based on convolutional neural networks and long short-term memory networks. The predicted cloud clusters, together with the relationship between the rainfall area and the cloud position, are applied to correct the 1–6-h precipitation forecast. We conduct comprehensive experiments to evaluate the proposed solution over China. Experimental results show that the deep learning model can successfully capture spatial characteristics and temporal variations between the sequences, and achieve reliable predictions of cloud clusters. The analysis further indicates that the rolling correction solution via the predicted cloud clusters has improved the precipitation forecast in China. The distribution of corrected precipitation forecast is more consistent with the observed precipitation compared to GRAPES_Meso forecast. In particular, the rolling correction model could enhance the forecast on “rain/no-rain” events, light rain, and moderate rain according to TS, ETS, BIAS, and FAR metrics.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"23 10","pages":""},"PeriodicalIF":3.0,"publicationDate":"2022-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1100","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43743564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0