International Journal of Climatology最新文献

{"title":"Shifting of the Zone of Occurrence of Extreme Weather Event—Heat Waves","authors":"Neetu Tyagi,&nbsp;Adarsh Dube,&nbsp;S. Lakshmi,&nbsp;Somenath Dutta,&nbsp;Akhil Srivastava","doi":"10.1002/joc.8856","DOIUrl":"https://doi.org/10.1002/joc.8856","url":null,"abstract":"<div>\u0000 \u0000 <p>In this study, an attempt has been made to examine whether there has been any significant shift in the region of occurrence of extreme weather events associated with high temperature in the past decades during the months of March to June Following the India Meteorological Department (IMD) guidelines, we have identified heatwave locations all over India for the period 1991–2020 (3 decades) using the MAUSAM report and the period 1961–2020 (6 decades) using IMD gridded datasets at 1° × 1° resolution. In the first part, an analysis of extreme weather events caused by heatwaves (HW) and severe heatwaves (SHW) has been made. In each decade, a broad region of recurrence associated with HW/SHW has been identified. This process is repeated for a decadal-wise study. We observed a spatial–temporal shift in the occurrence of HW/SHW events, with a significantly increasing and decreasing trend in Indian states with HW/SHW-prone regions. The west coastal region has seen an increase in HW locations starting with the Konkan Coast up to Kerala. Also, the North-eastern states are facing HW/SHW in the third decade, which is a contradiction to otherwise cooler conditions. In the third decade, SHW locations appear as marked from northwest to southeast India around the central region, as if following a linear structure. The occurrence of HW/SHW in hilly states like Meghalaya, Assam, Himachal Pradesh, and Uttarakhand is an unprecedented and disastrous condition that can be a dangerous trend for the future. This observational evidence provides valuable insights into the impact of climate change on extreme heat events and helps inform mitigation and adaptation strategies.</p>\u0000 </div>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climatological Context of the Severe Rain-on-Snow Flooding Event of March 2019 in Eastern Nebraska","authors":"Z. J. Suriano,&nbsp;S. Davidson,&nbsp;R. D. Dixon,&nbsp;T. Roy","doi":"10.1002/joc.8840","DOIUrl":"https://doi.org/10.1002/joc.8840","url":null,"abstract":"<div>\u0000 \u0000 <p>The rain-on-snow event of March 12–14, 2019, in eastern Nebraska was caused by a rapidly intensifying mid-latitude cyclone that resulted in over 80 mm of liquid precipitation and the ablation of over 25 mm of liquid equivalent in the snowpack. The resulting flood caused over $10 billion in damage by some estimates. Here, we sought to evaluate specific dimensions of this event within the broader climatological context to determine how unique the event was relative to a longer period of record. Results suggest that the mid-latitude cyclone had a central pressure over 30 hPa lower than its classified synoptic weather type, leading to greater warm advection and temperature and dewpoint anomalies as high as +8°C and+10°C, respectively. The 3-day sequence of weather types corresponding to the event was observed only three other times over a 1948–2021 period of record, while the 2-day sequence of just March 13–14 occurred just 25 other times. The magnitude of daily precipitation during the event was in the 100th percentile of all rain-on-snow (ROS) precipitation events for 16% of the basin and likely was a primary driver of observed flooding. Similarly, daily snow loss during the event across eastern Nebraska was above the 95th percentile relative to 1981–2021 climatology for most of eastern Nebraska. Collectively, our results suggest the March 2019 ROS event was an extreme event across multiple individual facets, but they were not without climatological precedent. As such, this event is a useful case study for understanding extreme rain-on-snow events across the Central United States.</p>\u0000 </div>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Has the Extent of Summer Monsoon Rainfall Activity Increased in Iran? A Long-Term Analysis of Trends and Connection With Monsoon Indices","authors":"Mohammad Rezaei,&nbsp;Farshad Pazhoh","doi":"10.1002/joc.8852","DOIUrl":"https://doi.org/10.1002/joc.8852","url":null,"abstract":"<div>\u0000 \u0000 <p>In the summer of 2022, Iran experienced severe flooding that caused extensive damage to infrastructure, agriculture, and residential areas. This event prompted an investigation into whether the frequency and extent of severe summer flooding in Iran have increased due to global warming. This study investigates long-term trends in Widespread Rainy Days (WRDs) in Iran during the summer season (June to September) and analyses their correlation with Indian summer monsoon indices, specifically the Convective Index (CI) and U-wind Index (UI). Reanalysis data, including precipitation, Sea Level Pressure (SLP), and Geopotential Height (GPH) from 1836 to 2015, were used for the analysis. WRDs in Iran were calculated for each year using the connected components labelling method. The results indicate a positive correlation between precipitation and WRDs with the CI, implying that an increase in Outgoing Longwave Radiation (OLR) in the Bay of Bengal leads to higher rainfall and more WRDs in Iran. Amongst all observed correlations, the highest correlation (<i>r</i> = 0.58) was found in southeastern Iran. On days with the highest CI values, negative anomalies in sea level pressure (SLP) and 850-hPa geopotential height (GPH) are observed. These anomalies, along with increased humidity advection, contribute to the occurrence of WRDs in Iran. Conversely, Iran's summer rainfall shows a negative correlation with the UI. On days with the highest UI values, no negative anomalies were observed in SLP and 850-hPa GPH, and reduced humidity advection resulted in the absence of WRDs in Iran. The study also reveals that the majority of WRDs occur in June, with the highest density observed in the southeast region of Iran. The Mann–Kendall test indicates a decrease in WRDs in Iran, particularly in June (<i>R</i>² = 17%) and September (<i>R</i>² = 24%). Whilst July and August also exhibit a decline, the trend is relatively weaker (<i>R</i>² = 2%). These findings demonstrate a statistically significant decline in WRDs over the 180-year period, contradicting the hypothesis of increased monsoon rains in Iran due to global warming.</p>\u0000 </div>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Copula-Based Approach to Nonstationary Bivariate Frequency Analysis of Short-Duration Precipitation Extremes in Huaihe River Basin, China","authors":"Huanyu Yang,&nbsp;Pengcheng Xu,&nbsp;Dong Wang,&nbsp;Vijay P. Singh,&nbsp;Zhilang Zhang,&nbsp;Miao Lu","doi":"10.1002/joc.8855","DOIUrl":"https://doi.org/10.1002/joc.8855","url":null,"abstract":"<div>\u0000 \u0000 <p>The risk of extreme rainfall events has increased due to climate change, necessitating the risk assessment of extreme rainfall events under a nonstationary framework. Since short-duration extreme rainfall events are more sensitive to environmental changes, and the current research on the risk of continuous short-duration extreme rainfall events is insufficient, this study presents a methodological framework for assessing the risk of short-duration rainfall extremes using a nonstationary model across the Huaihe River Basin in China from 1963 to 2015. The methodology includes the following components: (1) A quantile-based approach was used to identify the short-duration extreme rainfall events. (2) The risk of short-duration extreme rainfall events caused by climate change was calculated using nonstationary bivariate models and compared with those from stationary models. (3) The design values corresponding to the most-likely design event at different average annual reliability (AAR) were calculated based on copula models. The results illustrated that the intensity of rainfall duration and total rainfall of short-duration extreme rainfall events in most stations increased significantly after 2000. The width of the 90% confidence interval for the design values estimated based on AAR increased under both nonstationary marginal distributions and nonstationary copula models, indicating that the calculation of the design values will be affected in both scenarios. Therefore, it is necessary to use nonstationary bivariate models to assess the risk of short-duration extreme rainfall events under climate change. Overall, this study provides a systematic framework for conducting nonstationary risk assessments of short-duration extreme rainfall events.</p>\u0000 </div>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate Change Hotspots for Türkiye","authors":"Nazan An,&nbsp;M. Tufan Turp,&nbsp;Elif Bayindir,&nbsp;Yagmur Akverdi,&nbsp;Zeynep Nur Mirza,&nbsp;M. Levent Kurnaz","doi":"10.1002/joc.8825","DOIUrl":"https://doi.org/10.1002/joc.8825","url":null,"abstract":"<div>\u0000 \u0000 <p>Depending on various indicators, climate change may affect each region globally at varying risk levels. Therefore, identifying the ‘hotspots’ most likely to be affected by climate change in the future is a crucial step in ensuring those areas rapidly adapt to it. The study estimated the Standard Euclidean Distance (SED) for identifying hotspots of Türkiye using high-resolution climate projection data (10 × 10 km) and examined regional vulnerability in the long-term future over a 75-year period (2024–2099). The projections were made using RegCM4.4 driven by MPI-ESM-MR under the optimistic (RCP4.5) and pessimistic (RCP8.5) scenarios. The findings indicate that the hotspot regions in Türkiye are Southeastern Anatolia, Eastern Anatolia and the Mediterranean for RCP4.5, and Southeastern Anatolia, Eastern Anatolia, the Mediterranean and Central Anatolia for RCP8.5. The most critical indicators, however, are temperature-related indicators (i.e., Mean Air Temperature, Hot Seasons and Temperature Variability). Based on the findings, it is necessary to take preventive measures, particularly in highly vulnerable regions, to minimise potential damage. Additionally, multi-model ensemble studies should be applied to reduce the uncertainties and model-related variability, as well as to provide robust evidence of climate change.</p>\u0000 </div>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 7","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intraseasonal Oscillations and Hydroclimate of Northern South America, Central America and Mexico","authors":"Alejandro Builes-Jaramillo,&nbsp;Johanna Yepes,&nbsp;Hernán D. Salas,&nbsp;Juan M. Bedoya-Soto,&nbsp;Paris Rivera,&nbsp;Juliana Valencia,&nbsp;Alejandra M. Carmona","doi":"10.1002/joc.8848","DOIUrl":"https://doi.org/10.1002/joc.8848","url":null,"abstract":"<div>\u0000 \u0000 <p>We examine the influence of intraseasonal variability (10–90 days) on hydroclimatic variables across Northern South America, Central America and Mexico. This variability is driven by planetary and tropical oscillations, including Kelvin waves, Tropical Easterly Waves, Mixed Rossby-Gravity Waves and the Madden–Julian oscillation, all of which display distinct signals in the wavenumber–frequency power spectra. Our findings reveal that intraseasonal variability accounts for 10%–35% of the total variance, depending on the specific location, with Kelvin waves being the largest contributors to the outgoing longwave radiation variance in the study region. Additionally, we observed positive and negative precipitation anomalies across the region associated with each oscillatory process, which can be linked to anomalies in moisture transport and convection within the atmospheric column. The Madden–Julian oscillation contributes 10%–12% of precipitation over continental areas, while Tropical Easterly Waves and Mixed Rossby-Gravity waves account for approximately 40% of the precipitation over the continent. These findings offer new insights into the spatial and temporal patterns within the region. A deeper understanding, diagnosis and prediction of this timescale are crucial for economic sectors such as agriculture, energy generation, risk management and water resources.</p>\u0000 </div>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk Assessment of Extreme Precipitation in Northwest Iran in the Light of Changing Climate","authors":"Poya Fakour,&nbsp;Zbigniew Ustrnul,&nbsp;Agnieszka Wypych","doi":"10.1002/joc.8854","DOIUrl":"https://doi.org/10.1002/joc.8854","url":null,"abstract":"<p>The objective of this study is to conduct a regional risk analysis based on extreme precipitation trends at annual and seasonal time scales. It evaluates the trends of precipitation extremes over the Northwest of Iran, covering 600,000 km². ECMWF-ERA5 reanalysis precipitation data with a relatively high spatial resolution of 0.25° × 0.25° and daily temporal resolution are used for the long-term historical period from 1941 to 2020. The provided risk assessments are based on the integration of the special distribution of trends for 10 selected extreme precipitation indices (EPIs), which were assessed with a non-parametric Mann–Kendall test at the significance level of <i>α</i> = 0.05. Additionally, the difference in precipitation for the recent climate reference period (1991–2020) was compared to a subperiod 1941–1970, pursuing to distinguish shifts in precipitation patterns. The findings have found a meaningful increase in the frequency of daily heavy precipitation events over the explored period, specifically in the few latter decades. The trends reveal primarily positive patterns, with many being statistically significant. Furthermore, in some regions, total rainfall has increased by nearly 25% over the past three decades. The highest number of events occurs during the winter (DJF) followed by the spring (MAM) season. Nevertheless, looking at the monthly timescale, March records the highest number of extreme precipitation events. The strongest positive trend in intensity and frequency is associated with the autumn season (SON), particularly October and November in this region. Moreover, the highest number of grid points with notable positive trends is observed during autumn on the seasonal timescale and in November on the monthly timescale. Whilst the results of the annual survey show that 56.5% of the region is at risk of extreme precipitation, this percentage grows to 80.3% on the seasonal scale (SON), which highlights the areas with a higher probability of the occurrence of extreme precipitation events. Overall, the combined results of the EPIs trends indicate a significant shift towards more intense and frequent precipitation on interannual scales. Notably, most of this region can be classified as a susceptible area to extreme precipitation events and therefore at a high probability of flash floods, especially during the autumn season.</p>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/joc.8854","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drought to Flood to Drought: A Review of Definitions of Precipitation Whiplash Events, What Causes Them and Their Impacts Over the Continental United States","authors":"Esther Mullens,&nbsp;Johanna Engström","doi":"10.1002/joc.8850","DOIUrl":"https://doi.org/10.1002/joc.8850","url":null,"abstract":"<p>Precipitation whiplash, the rapid shift from drought to flooding, or vice versa, exacerbates the impact of both extremes compared to if they were to occur separately. The recognition of these types of events is relatively recent, and event precursors, driving meteorology and impacts are poorly understood. In response to this, this review summarises the current state of science of precipitation whiplash events in the United States, analysing event definitions, driving meteorology, impacts and the spatial distribution of the studies. Definitions vary considerably in temporal extent, from the transition between wet and dry conditions happening in less than a week to over a year. The climatological drivers and meteorological conditions creating precipitation whiplash events show significant diversity as well, both due to the varying event definitions and also due to the different geographical settings and range of scales of the studies. A wide range of definitions, drivers and impacts are described here, allowing researchers to better understand the phenomenon that is precipitation whiplash while also creating a foundation for future studies to delve deeper into the topic.</p>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/joc.8850","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Cold Frontal Life Cycle Climatology and Front–Cyclone Relationships Over the North Atlantic and Europe","authors":"Tobias Lichtenegger,&nbsp;Armin Schaffer,&nbsp;Albert Ossó,&nbsp;Oscar Martínez-Alvarado,&nbsp;Douglas Maraun","doi":"10.1002/joc.8830","DOIUrl":"https://doi.org/10.1002/joc.8830","url":null,"abstract":"<p>Atmospheric fronts and cyclones play an important role in day-to-day weather variability, especially in the mid-latitudes and during the winter season. Severe rainfall and windstorm events are often associated with the passage of a front or a cyclone. While there are many studies of individual fronts and climatologies of instantaneous fronts, there is no climatological study considering the whole frontal life cycle over time. Therefore, we use a front and cyclone tracking algorithm, together with a widely used front detection method, to detect and track cold fronts and cyclones over the North Atlantic and Europe in the extended winter season (October–March) in the ERA5 reanalysis data set. This enables a climatological study providing statistics of the frontal life cycle based on thousands of fronts. Several life cycle characteristics and frontal parameters are defined to investigate the frontal life cycle and the conditions and processes in the frontal region. Fronts are linked to their parent cyclone to study relationships between frontal and cyclonic properties. Cold fronts primarily develop over the Western North Atlantic and are found to decay at or soon after landfall on the European coast in most cases. Cold fronts tracked over the North Atlantic are found to last over 1 day longer and travel up to 1500 km farther on average than cold fronts tracked over the Mediterranean and over land. Cold frontal life cycle characteristics are strongly dependent on the North Atlantic Oscillation, with cold fronts appearing in a positive phase lasting longer and travelling faster and farther. Stronger cyclones are related to stronger frontal wind speeds at the surface as well as in the cold and warm sectors. The relationships between frontal and cyclonic properties are found to weaken over the course of their life cycle.</p>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/joc.8830","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144315053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precursors to Extreme Wintertime Cold in the Midwest United States","authors":"James M. Ryan,&nbsp;Ben Kravitz,&nbsp;Scott M. Robeson,&nbsp;Paul W. Staten","doi":"10.1002/joc.8849","DOIUrl":"https://doi.org/10.1002/joc.8849","url":null,"abstract":"<p>Cold air outbreaks (CAOs) are extreme weather events that affect millions of people every winter, including those in the US Midwest. Per our criteria (a sufficiently cold event over a wide area and a long period), we identified 43 wintertime CAOs in the Midwest region using data from 1980 to 2021 (approximately one per year). These occurred in the Midwest during three of five North American weather regimes. Two regimes' CAOs are related to a weak stratospheric polar vortex, consistent with previous research on CAOs in the neighbouring Great Plains region. A different regime, characterised by anomalous ridging along the west coast of North America, is the most common for Midwest CAOs, unlike in regions further to the west. Unlike the other two regimes, these so-called West Coast Ridge CAOs have no clear stratospheric connection. West Coast Ridge CAOs are instead linked to tropospheric processes on synoptic timescales, usually preceded by a weaker than average mid-tropospheric height gradient in the western Pacific about 10 days prior to CAO onset. Our results demonstrate a particular challenge for predicting some extreme events in the Midwest, with important implications for early warning systems.</p>","PeriodicalId":13779,"journal":{"name":"International Journal of Climatology","volume":"45 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/joc.8849","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}