Evaluation of convection-permitting extreme precipitation simulations for the south of France

Abstract. In the autumn, the French Mediterranean area is frequently exposed to heavy precipitation events whose daily accumulation can exceed 300 mm. One of the key processes contributing to these precipitation amounts is the deep convection, which can be resolved explicitly by state-or-the-art convection-permitting model to reproduce heavy rainfall events that are comparable to observations. However, this approach has never been used in climate simulation for the Mediterranean coastal region. In this research, we investigate the added values of using three ensembles of climate simulations at convection-permitting resolution (approx. 3 km) in replicating extreme precipitation events in both daily and shorter time scale over the South of France. These three convection-permitting simulations are performed with the Weather Research and Forecasting Model (WRF). They are forced by three EURO-CORDEX simulations, which are also downscaled with WRF at the resolution of 0.11° (approx. 12 km). We found that a convection-permitting approach provides a more realistic representation of extreme daily and 3-hourly rainfall simulations in comparison with EURO-CORDEX simulations. Their similarity with observations allows a use for climate change studies and its impacts.

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Changes in Intense Precipitation over the Central United States

Journal of Hydrometeorology ◽

10.1175/jhm-d-11-039.1 ◽

2012 ◽

Vol 13 (1) ◽

pp. 47-66 ◽

Cited By ~ 137

Author(s):

Pavel Ya. Groisman ◽

Richard W. Knight ◽

Thomas R. Karl

Keyword(s):

United States ◽

Extreme Precipitation ◽

Heavy Precipitation ◽

The Past ◽

Extreme Precipitation Events ◽

Intense Precipitation ◽

Central United States ◽

Extreme Rain ◽

Rain Events ◽

Precipitation Events

Abstract In examining intense precipitation over the central United States, the authors consider only days with precipitation when the daily total is above 12.7 mm and focus only on these days and multiday events constructed from such consecutive precipitation days. Analyses show that over the central United States, a statistically significant redistribution in the spectra of intense precipitation days/events during the past decades has occurred. Moderately heavy precipitation events (within a 12.7–25.4 mm day−1 range) became less frequent compared to days and events with precipitation totals above 25.4 mm. During the past 31 yr (compared to the 1948–78 period), significant increases occurred in the frequency of “very heavy” (the daily rain events above 76.2 mm) and extreme precipitation events (defined as daily and multiday rain events with totals above 154.9 mm or 6 in.), with up to 40% increases in the frequency of days and multiday extreme rain events. Tropical cyclones associated with extreme precipitation do not significantly contribute to the changes reported in this study. With time, the internal precipitation structure (e.g., mean and maximum hourly precipitation rates within each preselected range of daily or multiday event totals) did not noticeably change. Several possible causes of observed changes in intense precipitation over the central United States are discussed and/or tested.

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Listening to Stakeholders: Initiating Research on Sub-seasonal to Seasonal Heavy Precipitation Events in the Contiguous U.S. by First Understanding What Stakeholders Need

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-20-0313.1 ◽

2021 ◽

pp. 1-35

Author(s):

Olivia VanBuskirk ◽

Paulina Ćwik ◽

Renee A. McPherson ◽

Heather Lazrus ◽

Elinor Martin ◽

...

Keyword(s):

United States ◽

Environmental Management ◽

Predictive Models ◽

Extreme Precipitation ◽

Heavy Precipitation ◽

Role Playing ◽

Extreme Precipitation Events ◽

Rainfall Extremes ◽

Actionable Science ◽

Precipitation Events

AbstractHeavy precipitation events and their associated flooding can have major impacts on communities and stakeholders. There is a lack of knowledge, however, about how stakeholders make decisions at the sub-seasonal to seasonal (S2S) timescales (i.e., two weeks to three months). To understand how decisions are made and S2S predictions are or can be used, the project team for “Prediction of Rainfall Extremes at Sub-seasonal to Seasonal Periods” (PRES2iP) conducted a two-day workshop in Norman, Oklahoma, during July 2018. The workshop engaged 21 professionals from environmental management and public safety communities across the contiguous United States in activities to understand their needs for S2S predictions of potential extended heavy precipitation events. Discussions and role-playing activities aimed to identify how workshop participants manage uncertainty and define extreme precipitation, the timescales over which they make key decisions, and the types of products they use currently. This collaboration with stakeholders has been an integral part of PRES2iP research and has aimed to foster actionable science. The PRES2iP team is using the information produced from this workshop to inform the development of predictive models for extended heavy precipitation events and to collaboratively design new forecast products with our stakeholders, empowering them to make more-informed decisions about potential extreme precipitation events.

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Extreme precipitation events during the South Asian summer monsoon season in the past century

10.5194/egusphere-egu21-6418 ◽

2021 ◽

Author(s):

Renaud Falga ◽

Chien Wang

Keyword(s):

South Asian ◽

Extreme Events ◽

Extreme Precipitation ◽

Monsoon Season ◽

Past Century ◽

South Asian Summer Monsoon ◽

The South ◽

The Past ◽

Extreme Precipitation Events ◽

Precipitation Events

The South Asian monsoon system impacts the livelihoods of over a billion people. While the overall monsoon rainfall is believed to have decreased during the 20th century, there is a good agreement that the extreme precipitation events have been rising in some parts of India. As an important part of the Indian population is dependent on rainfed agriculture, such a rise in extremes, along with resulting flood events, can be all the more problematic. Although studies tend to link this rise in extreme events with anthropogenic forcing, some uncertainties remain on the exact causes. In order to examine the correlation between anthropogenic forcings and the different trends in extreme events, we have analyzed the high-resolution daily rainfall data in the past century delivered by the Indian Meteorological Department alongside several other economic and ecological estimates. The results from this analysis will be presented in detail.

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Trends, change points and spatial variability in extreme precipitation events from 1961 to 2017 in China

Hydrology Research ◽

10.2166/nh.2020.095 ◽

2020 ◽

Vol 51 (3) ◽

pp. 484-504 ◽

Cited By ~ 3

Author(s):

Linchao Li ◽

Yufeng Zou ◽

Yi Li ◽

Haixia Lin ◽

De Li Liu ◽

...

Keyword(s):

Extreme Precipitation ◽

Extreme Event ◽

Heavy Precipitation ◽

Kendall Test ◽

Temporal Variations ◽

Change Points ◽

Monthly Precipitation ◽

Flood Peak ◽

Extreme Precipitation Events ◽

Precipitation Events

Abstract Extreme precipitation events vary with different sub-regions, sites and years and show complex characteristics. In this study, the temporal variations, trends with significance and change points in the annual time series of 10 extreme precipitation indices (EPIs) at 552 sites and in seven sub-regions were analyzed using the modified Mann–Kendall test and sequential Mann–Kendall analysis. Three representative (extremely wet, normal and extremely dry) years from 1961 to 2017 were selected by the largest, 50%, and smallest empirical frequency values in China. The spatiotemporal changes in the EPIs during the three representative years were analyzed in detail. The results showed that during 1961–2017, both the consecutive wet or dry days decreased significantly, while the number of heavy precipitation days had no significant trend, and the other seven wet EPIs increased insignificantly. The abrupt change years of the 10 EPIs occurred 32 and 40 times from 1963 to 1978 and from 1990 to 2016, respectively, regardless of sub-region. The extremely dry (or wet) events mainly occurred in western (or southwestern) China, implying a higher extreme event risk. The extremely wet, normal and extremely dry events from 1961 to 2017 occurred in 2016, 1997 and 2011 with empirical frequencies of 1.7%, 50% and 98.3%, respectively. In addition, 1998 was the second-most extremely wet year (empirical frequency was 3.7%). The monthly precipitation values were larger from February to August in 1998, forming a much earlier flood peak than that of 2016. The 10 EPIs had close connections with Normalized Difference Vegetation Indexes during the 12 months of 1998 and 2016. This study provides useful references for disaster prevention in China.

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Predicting Extreme-Precipitation Effects on the Geomorphology of Small Mountain Catchments: Towards an Improved Understanding of the Consequences for Freshwater Biodiversity and Ecosystems

Water ◽

10.3390/w12010079 ◽

2019 ◽

Vol 12 (1) ◽

pp. 79 ◽

Cited By ~ 4

Author(s):

Stefano Segadelli ◽

Federico Grazzini ◽

Michele Adorni ◽

Maria Teresa De Nardo ◽

Anna Fornasiero ◽

...

Keyword(s):

Extreme Precipitation ◽

Debris Flows ◽

Mitigation Measures ◽

Convective System ◽

Stream Channels ◽

Freshwater Biodiversity ◽

Rainfall Analysis ◽

Extreme Precipitation Events ◽

Hourly Rainfall ◽

Precipitation Events

In 2015 an intense rainfall event hit the Valleys of the Trebbia, Nure, and Aveto watercourses in the Northern Apennines. In about 6 h a mesoscale convective system deployed a stunning amount of precipitation of 340 mm, with an extreme hourly rainfall intensity of >100 mm/h. It triggered debris flows along slopes and stream channels, landslides and floods, which caused serious damages. Through the optimal combination of rainfall data and radar volumes, in this work we present a detailed rainfall analysis, which will serve as a basis to create a quantitative correlation with debris flows over elementary hydrological units. We aim at providing an objective basis for future predictions, starting from the recognition of the forcing meteorological events, and then arriving at the prediction of triggering phenomena and to the debris-flow type. We further provide seven observations/case studies on the effects of extreme-precipitation events on freshwater environments in small mountain catchments. Extreme-precipitation events are becoming more frequent and widespread globally but their ecological effects are still insufficiently understood. In general, the effects of extreme events on inland-waters’ ecosystems are highly context-dependent, ranging from deleterious to beneficial. We therefore highlight the necessity of further studies to characterize these effects in more depth to be able to include appropriate mitigation measures in environmental planning and stewardship.

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Large-Scale Flow Patterns Associated with Extreme Precipitation and Atmospheric Rivers over Norway

Monthly Weather Review ◽

10.1175/mwr-d-18-0362.1 ◽

2019 ◽

Vol 147 (4) ◽

pp. 1415-1428 ◽

Cited By ~ 7

Author(s):

Imme Benedict ◽

Karianne Ødemark ◽

Thomas Nipen ◽

Richard Moore

Keyword(s):

Extreme Precipitation ◽

Large Scale ◽

Moisture Flux ◽

Cold Season ◽

Fuzzy Cluster ◽

The South ◽

Atmospheric Rivers ◽

The North ◽

Extreme Precipitation Events ◽

Precipitation Events

Abstract A climatology of extreme cold season precipitation events in Norway from 1979 to 2014 is presented, based on the 99th percentile of the 24-h accumulated precipitation. Three regions, termed north, west, and south are identified, each exhibiting a unique seasonal distribution. There is a proclivity for events to occur during the positive phase of the NAO. The result is statistically significant at the 95th percentile for the north and west regions. An overarching hypothesis of this work is that anomalous moisture flux, or so-called atmospheric rivers (ARs), are integral to extreme precipitation events during the Norwegian cold season. An objective analysis of the integrated vapor transport illustrates that more than 85% of the events are associated with ARs. An empirical orthogonal function and fuzzy cluster technique is used to identify the large-scale weather patterns conducive to the moisture flux and extreme precipitation. Five days before the event and for each of the three regions, two patterns are found. The first represents an intense, southward-shifted jet with a southwest–northeast orientation. The second identifies a weak, northward-shifted, zonal jet. As the event approaches, regional differences become more apparent. The distinctive flow pattern conducive to orographically enhanced precipitation emerges in the two clusters for each region. For the north and west regions, this entails primarily zonal flow impinging upon the south–north-orientated topography, the difference being the latitude of the strong flow. In contrast, the south region exhibits a significant southerly component to the flow.

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How Well Can IMERG Products Capture Typhoon Extreme Precipitation Events over Southern China?

Remote Sensing ◽

10.3390/rs11010070 ◽

2019 ◽

Vol 11 (1) ◽

pp. 70 ◽

Cited By ~ 11

Author(s):

Chaoying Huang ◽

Junjun Hu ◽

Sheng Chen ◽

Asi Zhang ◽

Zhenqing Liang ◽

...

Keyword(s):

Extreme Precipitation ◽

Southern China ◽

Correlation Coefficients ◽

Heavy Precipitation ◽

Spatiotemporal Variability ◽

Bias Analysis ◽

Extreme Precipitation Events ◽

Precipitation Measurement ◽

Global Precipitation ◽

Precipitation Events

This study assesses the performance of the latest version 05B (V5B) Integrated Multi-Satellite Retrievals for Global Precipitation Measurement (GPM) (IMERG) Early and Final Runs over southern China during six extremely heavy precipitation events brought by six powerful typhoons from 2016 to 2017. Observations from a dense network composed of 2449 rain gauges are used as reference to quantify the performance in terms of spatiotemporal variability, probability distribution of precipitation rates, contingency scores, and bias analysis. The results show that: (1) both IMERG with gauge calibration (IMERG_Cal) and without gauge correction (IMERG_Uncal) generally capture the spatial patterns of storm-accumulated precipitation with moderate to high correlation coefficients (CCs) of 0.57–0.87, and relative bias (RB) varying from −17.21% to 30.58%; (2) IMERG_Uncal and IMERG_Cal capture well the area-average hourly series of precipitation over rainfall centers with high CCs ranging from 0.78 to 0.94; (3) IMERG_Cal tends to underestimate precipitation especially the rainfall over the rainfall centers when compared to IMERG_Uncal. The IMERG Final Run shows promising potentials in typhoon-related extreme precipitation storm applications. This study is expected to give useful feedbacks about the latest V5B Final Run IMERG product to both algorithm developers and the scientific end users, providing a better understanding of how well the V5B IMERG products capture the typhoon extreme precipitation events over southern China.

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Spatial and Temporal Analysis of Precipitation Extremities of Eastern Nepal in the Last Two Decades (1997–2016)

10.5194/egusphere-egu2020-2784 ◽

2020 ◽

Author(s):

Sunil Subba ◽

Yaoming Ma ◽

Weiqiang Ma

Keyword(s):

Climate Change ◽

Extreme Events ◽

Extreme Precipitation ◽

Tropical Rainfall Measuring Mission ◽

Heavy Precipitation ◽

Temporal Analysis ◽

Extreme Precipitation Events ◽

Slope Estimator ◽

The Impact ◽

Precipitation Events

In recent days there have been discussions regarding the impact of climate change and its vagaries of the weather, particularly concerning extreme events. Nepal, being a mountainous country, is more susceptible to precipitation extreme events and related hazards, which hinder the socioeconomic development of the nation. In this regard, this study aimed to address this phenomenon for one of the most naturally and socioeconomically important regions of Nepal, namely, Eastern Nepal. The data were collected for the period of 1997 to 2016. The interdecadal comparison for two periods (1997&#8211;2006 and 2007&#8211;2016) was maintained for the calculation of extreme precipitation indices as per recommended by Expert Team on Climate Change Detection and Indices. Linear trends were calculated by using Mann&#8208;Kendall and Sen's Slope estimator. The average annual precipitation was found to be decreasing at an alarming rate of &#8722;20 mm/year in the last two decades' tenure. In case of extreme precipitation events, consecutive dry days, one of the frequency indices, showed a solo increase in its trend (mostly significant). Meanwhile, all the intensity indices of extreme precipitation showed decreasing trends (mostly insignificant). Thus, it can be concluded that Eastern Nepal has witnessed some significant drier days in the last two decades, as the events of heavy, very heavy, extremely heavy precipitation events, and annual wet day precipitation (PRCPTOT) were found to be decreasing. The same phenomena were also seen in the Tropical Rainfall Measuring Mission 3B42 V7 satellite precipitation product for whole Nepal.

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Multi-Indicator Evaluation for Extreme Precipitation Events in the Past 60 Years over the Loess Plateau

Water ◽

10.3390/w12010193 ◽

2020 ◽

Vol 12 (1) ◽

pp. 193 ◽

Cited By ~ 1

Author(s):

Chaoxing Sun ◽

Guohe Huang ◽

Yurui Fan

Keyword(s):

Loess Plateau ◽

Return Period ◽

Extreme Precipitation ◽

Precipitation Amount ◽

Heavy Precipitation ◽

The Loess Plateau ◽

Extreme Precipitation Events ◽

Daily Precipitation Data ◽

Joint Return ◽

Precipitation Events

The unique characteristics of topography, landforms, and climate in the Loess Plateau make it especially important to investigate its extreme precipitation characteristics. Daily precipitation data of Loess Plateau covering a period of 1959–2017 are applied to evaluate the probability features of five precipitation indicators: the amount of extreme heavy precipitation (P95), the days with extreme heavy precipitation, the intensity of extreme heavy precipitation (I95), the continuous dry days, and the annual total precipitation. In addition, the joint risk of different combinations of precipitation indices is quantitatively evaluated based on the copula method. Moreover, the risk and severity of each extreme heavy precipitation factor corresponding to 50-year joint return period are achieved through inverse derivation process. Results show that the precipitation amount and intensity of the Loess Plateau vary greatly in spatial distribution. The annual precipitation in the northwest region may be too concentrated in several rainstorms, which makes the region in a serious drought state for most of the year. At the level of 10-year return period, more than five months with no precipitation events would occur in the Northwest Loess Plateau. While, P95 or I95 events of 100-year level may be encountered in a 50-year return period and in the southeastern region, which means there are foreseeable long-term extreme heavy precipitation events.

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A Comparison of CMIP3 Simulations of Precipitation over North America with Observations: Daily Statistics and Circulation Features Accompanying Extreme Events

Journal of Climate ◽

10.1175/jcli-d-12-00374.1 ◽

2013 ◽

Vol 26 (10) ◽

pp. 3209-3230 ◽

Cited By ~ 26

Author(s):

Anthony M. DeAngelis ◽

Anthony J. Broccoli ◽

Steven G. Decker

Keyword(s):

North America ◽

Extreme Events ◽

Extreme Precipitation ◽

Large Scale ◽

Climate Model ◽

Heavy Precipitation ◽

Convective Precipitation ◽

Southern Mexico ◽

Extreme Precipitation Events ◽

Precipitation Events

Abstract Climate model simulations of daily precipitation statistics from the third phase of the Coupled Model Intercomparison Project (CMIP3) were evaluated against precipitation observations from North America over the period 1979–99. The evaluation revealed that the models underestimate the intensity of heavy and extreme precipitation along the Pacific coast, southeastern United States, and southern Mexico, and these biases are robust among the models. The models also overestimate the intensity of light precipitation events over much of North America, resulting in fairly realistic mean precipitation in many places. In contrast, heavy precipitation is simulated realistically over northern and eastern Canada, as is the seasonal cycle of heavy precipitation over a majority of North America. An evaluation of the simulated atmospheric dynamics and thermodynamics associated with extreme precipitation events was also conducted using the North American Regional Reanalysis (NARR). The models were found to capture the large-scale physical mechanisms that generate extreme precipitation realistically, although they tend to overestimate the strength of the associated atmospheric circulation features. This suggests that climate model deficiencies such as insufficient spatial resolution, inadequate representation of convective precipitation, and overly smoothed topography may be more important for biases in simulated heavy precipitation than errors in the large-scale circulation during extreme events.

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