Atmospheric Science Letters最新文献

The profound influence of the North Atlantic Ocean on Northeast Asia: A comprehensive multi-model study

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-11-11 DOI: 10.1002/asl.1280

Paul-Arthur Monerie, Buwen Dong, Weiwen Sun, Lixia Zhang

{"title":"The profound influence of the North Atlantic Ocean on Northeast Asia: A comprehensive multi-model study","authors":"Paul-Arthur Monerie, Buwen Dong, Weiwen Sun, Lixia Zhang","doi":"10.1002/asl.1280","DOIUrl":"https://doi.org/10.1002/asl.1280","url":null,"abstract":"We assess the effects of the North Atlantic Sea surface temperature multidecadal variability on Northeast Asia using a set of sensitivity experiments (with a total of 530 ensemble members). We show that a warming of the North Atlantic Ocean leads to a strong and robust increase in temperature over Northeast Asia, which is replicated by a large majority of ensemble members. We show that the effect of the North Atlantic on Northeast Asia is model and season-dependent. We focus on two seasons, for which response to the North Atlantic Ocean is the most robust (autumn) and the less robust (spring) as indicated by the number of models that simulate a statistically significant change in surface air temperature. We use a clustering method to identify the sources of differences between models in simulating the effects of warming in the North Atlantic. We find that the primary mechanism linking the North Atlantic to Northeast Asia is a perturbation of the circumglobal teleconnection pattern (i.e., of the upper tropospheric atmospheric circulation), which allows modulation of the near-surface atmospheric circulation and an increase in temperature over East Asia. A second mechanism is related to the influence of the North Atlantic on the Pacific Ocean and the resulting effects on atmospheric circulation over Northeast Asia.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1280","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142759873","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

Interdecadal change in the relationship between the Antarctic oscillation and autumn rainfall in the Yunnan–Guizhou plateau of Southwest China

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-11-11 DOI: 10.1002/asl.1278

Yusen Li, Yong Zhao, Lixia Meng

{"title":"Interdecadal change in the relationship between the Antarctic oscillation and autumn rainfall in the Yunnan–Guizhou plateau of Southwest China","authors":"Yusen Li, Yong Zhao, Lixia Meng","doi":"10.1002/asl.1278","DOIUrl":"https://doi.org/10.1002/asl.1278","url":null,"abstract":"The interdecadal change in the relationship between the Antarctic Oscillation (AAO) and autumn rainfall in the Yunnan–Guizhou Plateau of Southwest China is investigated by using the observed autumn rainfall data at 119 stations and the National Centers for Environment Prediction/National Center for Atmospheric Research reanalysis data for the period 1961–2021. Results show the AAO correlates well with the autumn rainfall in the Yunnan–Guizhou Plateau for the second period (2002–2021) because the AAO becomes stronger. The possible influencing mechanism of AAO on autumn rainfall in the Yunnan–Guizhou Plateau during 2002–2021 is related to the meridional teleconnection pattern and associated convection over the Philippine Sea. The positive AAO can trigger a meridional teleconnection pattern in the upper troposphere to propagate from the southern Pacific to northern Pacific and cause anomalous westerly over the tropical west Pacific, which inhibits the convection over the Philippine Sea. On the one hand, the weakened convection over the Philippine Sea causes the anomalous ascending motion over the Yunnan–Guizhou Plateau; on the other hand, it results in an anomalous anticyclone over the tropical Northwest Pacific and strengthens the transport of water vapor from the tropical Pacific to the Yunnan–Guizhou Plateau.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1278","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762270","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

Wildfire aerosols and their impact on weather: A case study of the August 2021 fires in Greece using the WRF-Chem model

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-11-08 DOI: 10.1002/asl.1267

Anastasios Rovithakis, Apostolos Voulgarakis

{"title":"Wildfire aerosols and their impact on weather: A case study of the August 2021 fires in Greece using the WRF-Chem model","authors":"Anastasios Rovithakis, Apostolos Voulgarakis","doi":"10.1002/asl.1267","DOIUrl":"https://doi.org/10.1002/asl.1267","url":null,"abstract":"Wildfires are significant contributors to atmospheric gases and aerosols, impacting air quality and composition. This pollution from fires also affects radiative forcing, influencing short-term weather patterns and climate dynamics. Our research employs the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) to investigate the repercussions of wildfires on aerosol abundances and associated immediate weather responses. We examine the summer season of 2021, a period marked by severe wildfire events in the country during a heatwave period. We conducted sensitivity experiments including and excluding wildfire emissions to measure their effects on aerosol optical depth (AOD), radiative forcing, and weather features such as temperature, humidity, clouds, and atmospheric circulation. Our findings demonstrate that the radiative impacts of wildfires negatively influence the local temperature over the fire smoke plume-affected areas. Conversely, neighbouring areas of continental Greece experience increases in temperature due to remote effects of wildfire emissions, caused by meteorological feedbacks that reduce atmospheric humidity. Crucially, including fire emissions significantly improves the simulated surface temperatures predicted by the model over the Greek domain. Our work demonstrates that wildfire-generated aerosols can significantly impact weather conditions and highlights the importance of including both local radiative effects and remote feedback for achieving more accurate weather prediction.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1267","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762112","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 urban heat island circulation and convective cells through dynamic mode decomposition

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-10-30 DOI: 10.1002/asl.1279

Takuto Sato, Hideitsu Hino, Hiroyuki Kusaka

{"title":"Separating urban heat island circulation and convective cells through dynamic mode decomposition","authors":"Takuto Sato, Hideitsu Hino, Hiroyuki Kusaka","doi":"10.1002/asl.1279","DOIUrl":"https://doi.org/10.1002/asl.1279","url":null,"abstract":"This study applies dynamic mode decomposition (DMD) to three-dimensional simulation results of urban heat island circulation (UHIC, which is horizontal circulation) and thermals (vertical convections). The aim of this study is to revisit how these phenomena coexist based on the characteristics of temporal changes in the flow field. We used DMD to obtain the dominant spatial patterns and information on temporal changes. One of the modes of horizontal wind, which does not change temporally (no oscillation or amplification), exhibits a spatial UHIC pattern. The unique feature of this UHIC mode is that there are small-scale striated structures (150–200 m) and large-scale convergence. The other modes are time-varying (oscillating and decaying) and represent smaller spatial-scale phenomena (150–250 m), such as thermals. The frequency of each mode takes various values, some of which are lower than the lifetime of thermals in accordance with the Deardorff convective scale (~10 min). These low-frequency modes showed striated structures similar to that observed in the UHIC modes. These results suggest that UHIC and thermals deform each other through components that vary in long temporal scales.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1279","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762700","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

Predictability of European winter 2022/23

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-10-22 DOI: 10.1002/asl.1275

Nicky Stringer, Adam A. Scaife, Chris Bulmer, Paul Davies, Nick Dunstone, Margaret Gordon, Sarah Ineson, Jeff Knight, Joseph Mancell, Peter McLean, Doug Smith, Brent Walker, Christopher Walsh

{"title":"Predictability of European winter 2022/23","authors":"Nicky Stringer, Adam A. Scaife, Chris Bulmer, Paul Davies, Nick Dunstone, Margaret Gordon, Sarah Ineson, Jeff Knight, Joseph Mancell, Peter McLean, Doug Smith, Brent Walker, Christopher Walsh","doi":"10.1002/asl.1275","DOIUrl":"https://doi.org/10.1002/asl.1275","url":null,"abstract":"The boreal winter of 2022/23 was notable as a third consecutive winter in which La Niña had an influence on the European weather. The GloSea6 seasonal forecast system predicted a blocked circulation pattern in the North Atlantic in early winter (December), and then a transition through mid-winter (January) into a more zonal pattern in late winter (February), consistent with the canonical La Niña teleconnection pattern seen previously. The seasonal forecast for the UK was an increased likelihood of near average temperatures, and drier- and calmer-than-average conditions. Both the predicted broad-scale circulation patterns and UK winter mean weather conditions verified well against observations, and we show that seasonal forecasts of the North Atlantic Oscillation (NAO) over the last 10 winters show similar skill to previously reported hindcasts. Throughout the winter, the Madden–Julian Oscillation (MJO) was particularly active. On three occasions, it exhibited strong phases 6 and 7. There was also a sudden stratospheric warming (SSW) that occurred on 16th February. This was followed by colder conditions and associated impacts similar to the canonical negative NAO response over the UK, although the main impact fell in March and so did not affect the winter (December–January–February) mean conditions.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1275","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762576","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

Sensitivity of simulated MJO to model vertical resolution in GAMIL3

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-10-17 DOI: 10.1002/asl.1277

He Wang, Lijuan Li, Bin Wang, Xiao Wang, Ye Pu

引用次数: 0

Quantifying free tropospheric moisture sources over the western tropical Atlantic with numerical water tracers and isotopes

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-10-13 DOI: 10.1002/asl.1274

Svetlana Botsyun, Franziska Aemisegger, Leonie Villiger, Ingo Kirchner, Stephan Pfahl

{"title":"Quantifying free tropospheric moisture sources over the western tropical Atlantic with numerical water tracers and isotopes","authors":"Svetlana Botsyun, Franziska Aemisegger, Leonie Villiger, Ingo Kirchner, Stephan Pfahl","doi":"10.1002/asl.1274","DOIUrl":"https://doi.org/10.1002/asl.1274","url":null,"abstract":"Tropical free-tropospheric humidity plays a crucial role for the Earth's radiative balance and climate sensitivity. In addition to atmospheric humidity, stable water isotopes can provide important information about the hydrological cycle. We use the isotope- and water tagging-enabled version of the COSMOiso model to determine isotopic fingerprints of diagnosed moisture pathways over the western tropical Atlantic (WTA). A convection-permitting, high-resolution (5 km) nudged simulation is performed for January–February 2020. During this period, the target region is characterized by alternating large-scale circulation regimes with different humidity and isotope signatures. Moist conditions in the middle troposphere (300–650 hPa) are associated with moisture transport from the south, east, southeast, as well as evaporation from the North Atlantic, while dry conditions correspond to extratropical transport from the north and west. To predict the contribution of different moisture sources, we used a statistical model based on the local specific humidity and temperature as predictors and obtained an R-squared (R2) of 0.52. Adding water isotopes improved the prediction (R2 = 0.73), showing that isotopes provide unique information on moisture sources and transport patterns beyond conventional local observations.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1274","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762358","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

Upstream influence of midlatitude jet stream biases in boreal summer

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-10-08 DOI: 10.1002/asl.1272

Lina Boljka, Ingo Bethke, Dandan Tao, Camille Li

{"title":"Upstream influence of midlatitude jet stream biases in boreal summer","authors":"Lina Boljka, Ingo Bethke, Dandan Tao, Camille Li","doi":"10.1002/asl.1272","DOIUrl":"https://doi.org/10.1002/asl.1272","url":null,"abstract":"Climate models exhibit biases in the mean state and in variability across different regions of the Earth. For example, atmosphere-only models have a poleward bias in summertime jet streams across the Northern Hemisphere (NH). This can result from many processes, including misrepresentation of Rossby waves that can propagate in different directions and thereby interact with jet streams. However, Rossby-wave biases can result from biased background state of the climate system as well. The propagation speed of Rossby waves depends on jet stream strength, thus a poleward displacement of the jet stream can hinder westward propagation of Rossby waves at higher latitudes and displace eastward propagating Rossby waves (downstream development). These biases then impact other regions resulting in biased atmospheric circulation across the NH. Indeed, in this study we confirm this via regional nudging experiments within the Norwegian Earth System Model. Namely, nudged horizontal winds over the North Pacific can improve Rossby wave statistics and thereby atmospheric circulation over Eurasia (i.e., upstream). However, nudging over the North Atlantic has little effect on boreal summer atmospheric circulation. This implies that improving biases over the North Pacific is crucial for a better representation of modelled boreal summer circulation over Eurasia.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 12","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1272","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762113","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

Change detection of the Köppen climate zones in Southeastern Europe 东南欧柯本气候区的变化探测

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-10-02 DOI: 10.1002/asl.1270

Gordan Mimić, Zorica Podraščanin, Biljana Basarin

{"title":"Change detection of the Köppen climate zones in Southeastern Europe","authors":"Gordan Mimić, Zorica Podraščanin, Biljana Basarin","doi":"10.1002/asl.1270","DOIUrl":"https://doi.org/10.1002/asl.1270","url":null,"abstract":"The study exploits the air temperature and precipitation data from ERA5-Land reanalysis and E-OBS gridded observations that are freely available from the Copernicus Climate Change Service. The objectives of the study are to analyze the distribution of Köppen climate zones and to detect the changes in the presence and coverage of the specific climate types in Southeastern Europe. The results are shown separately for the following reference periods: 1961–1990, 1971–2000, 1981–2010, and 1991–2020. In the period 1961–1990, the most dominant climate type in Southeastern Europe was fully humid temperate climate with warm summer (Cfb), while fully humid continental climate with warm summer (Dfb) was also highly present there, together with fully humid temperate climate with hot summer (Cfa). In the period 1991–2020, the shift of Köppen climate zones appeared in such a way that the area with Dfb continental climate, that is often called snow or cold climate, is significantly reduced and this type is replaced with Cfb temperate climate. At the same time, Cfa climate type with hot summer is spread across wider area, mainly instead of Cfb with warm summer, now reaching almost the same percentage of coverage as Cfb type.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 11","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1270","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579573","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

Are convection-permitting climate projections reliable for urban planning over Africa? A case study of Johannesburg 允许对流的气候预测对非洲城市规划可靠吗？约翰内斯堡案例研究

IF 2 4区地球科学

Atmospheric Science Letters Pub Date : 2024-09-30 DOI: 10.1002/asl.1264

William J. Keat, Chris J. Short, Elizabeth J. Kendon

{"title":"Are convection-permitting climate projections reliable for urban planning over Africa? A case study of Johannesburg","authors":"William J. Keat, Chris J. Short, Elizabeth J. Kendon","doi":"10.1002/asl.1264","DOIUrl":"https://doi.org/10.1002/asl.1264","url":null,"abstract":"Cities are particularly vulnerable to surface water flooding. It is also well-known that they influence local rainfall themselves, which has important implications for climate change adaptation planning for cities. At km-scale resolution, convection-permitting climate models (CPCMs) better resolve cities and should better represent local urban temperature and rainfall modifications. However, using state-of-the-art pan-African CPCM simulations with the Met Office Unified Model (CP4), we show that for the city of Johannesburg, South Africa, this is not the case. A significant enhancement of rainfall occurs over the city compared with surrounding rural areas, which is not seen in available observations. We demonstrate this is associated with an overestimated urban heat island effect, which leads to additional triggering of rainfall. Urban signals in future rainfall change are small compared with changes in the wider surroundings, the latter of which we expect to be more reliable than in models with parameterized convection. This suggests that deficiencies in representation of urban processes are of secondary importance in terms of future percentage change in rainfall. We recommend urban planners apply relative changes in CP4 as an uplift to observations, where available, or treat absolute future rainfall as an upper estimate if used directly.","PeriodicalId":50734,"journal":{"name":"Atmospheric Science Letters","volume":"25 11","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asl.1264","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579679","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