Future extreme precipitation intensities based on historic events

Future extreme precipitation intensities based on a historic event

Hydrology and Earth System Sciences ◽

10.5194/hess-22-3777-2018 ◽

2018 ◽

Vol 22 (7) ◽

pp. 3777-3788 ◽

Cited By ~ 14

Author(s):

Iris Manola ◽

Bart van den Hurk ◽

Hans De Moel ◽

Jeroen C. J. H. Aerts

Keyword(s):

Extreme Precipitation ◽

Impact Analysis ◽

Numerical Models ◽

Summer Precipitation ◽

Heavy Precipitation ◽

Dew Point ◽

Precipitation Event ◽

Weather Model ◽

Intensity Changes ◽

Nwp Model

Abstract. In a warmer climate, it is expected that precipitation intensities will increase, and form a considerable risk of high-impact precipitation extremes. This study applies three methods to transform a historic extreme precipitation event in the Netherlands to a similar event in a future warmer climate, thus compiling a “future weather” scenario. The first method uses an observation-based non-linear relation between the hourly-observed summer precipitation and the antecedent dew-point temperature (the Pi–Td relation). The second method simulates the same event by using the convective-permitting numerical weather model (NWP) model HARMONIE, for both present-day and future warmer conditions. The third method is similar to the first method, but applies a simple linear delta transformation to the historic data by using indicators from The Royal Netherlands Meteorological Institute (KNMI)'14 climate scenarios. A comparison of the three methods shows comparable intensity changes, ranging from below the Clausius–Clapeyron (CC) scaling to a 3 times CC increase per degree of warming. In the NWP model, the position of the events is somewhat different; due to small wind and convection changes, the intensity changes somewhat differ with time, but the total spatial area covered by heavy precipitation does not change with the temperature increase. The Pi–Td method is simple and time efficient compared to numerical models. The outcome can be used directly for hydrological and climatological studies and for impact analysis, such as flood-risk assessments.

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The Role of Aerosols in Convective Processes during the Midsummer Drought in the Caribbean

Advances in Meteorology ◽

10.1155/2015/261239 ◽

2015 ◽

Vol 2015 ◽

pp. 1-16 ◽

Cited By ~ 3

Author(s):

Nathan Hosannah ◽

Hamed Parsiani ◽

Jorge E. González

Keyword(s):

Heavy Precipitation ◽

Atmospheric Modeling ◽

Dew Point ◽

Saharan Dust ◽

Convective Precipitation ◽

Precipitation Event ◽

Atmospheric Conditions ◽

Cloud Resolving Model ◽

The Caribbean

Saharan dust (SD) heavily impacts convective precipitation in the Caribbean. To better understand the role of SD in precipitation development during the midsummer drought (MSD), an observational campaign, centered at the city of Mayagüez, Puerto Rico (18.21 N, 67.13 W), between 3 June and 15 July 2014, was conducted in order to select a range of atmospheric conditions to be simulated using the Regional Atmospheric Modeling System (RAMS) cloud resolving model under “no SD” and “SD” conditions. The events included one dry day with moderate-heavy SD, one localized moderate rainfall event with moderate SD, one island-wide light precipitation event with heavy SD, and one island-wide heavy precipitation event with light-moderate SD. Model results show that (1) precipitation results are improved when compared with observation with the presence of SD, (2) precipitation, cloud fraction, dew point temperatures, and humidity are significantly reduced under SD conditions, (3) precipitation can occur when SD is removed for a dry day, (4) there is evidence of rain being delayed due to the presence of SD without rainfall intensity or accumulation increases, (5) liquid mixing ratio increases of up to 1.4 g kg−1occur in the absence of SD, and (6) vertical wind increases of up to 0.8 m s−1occur in the absence of SD.

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Building Resilience After Climate-Related Extreme Events: Lessons Learned from Extreme Precipitation in Schwäbisch Gmünd

Journal of Extreme Events ◽

10.1142/s2345737620500104 ◽

2020 ◽

Vol 07 (01n02) ◽

pp. 2050010

Author(s):

Britta V. Weißer ◽

Ali Jamshed ◽

Jörn Birkmann ◽

Joanna M. McMillan

Keyword(s):

Extreme Events ◽

Extreme Precipitation ◽

Household Survey ◽

Heavy Precipitation ◽

Precipitation Event ◽

Heavy Precipitation Event ◽

Extreme Precipitation Events ◽

Pluvial Flooding ◽

Precautionary Measures ◽

Precipitation Events

In 2016, heavy precipitation events in Southern Germany demonstrated that pluvial flooding can cause serious damages, not just in large cities but also in small and medium-sized cities. Hazard-oriented disaster management approaches to better address such spatially ubiquitous extreme events are already being developed. However, integrated strategies to reduce risk and to promote climate-resilient development pathways through both private precautionary measures and integrated urban planning are still underdeveloped. Considering the uncertainties associated with heavy precipitation, analyzing and understanding damages, strengthening people’s preparedness and improving preventative measures are central components of resilience building. This paper complements existing empirical studies on households’ preparedness and provides further insight into how resilience to flooding from heavy precipitation in cities can be strengthened. We do this by analyzing the damages caused by one particular heavy precipitation event, the preparedness of people in the affected city and their perceptions of responsibilities for improving precautionary measures. This paper presents the results from a household survey with a total of 1,128 completed questionnaires which was carried out in Schwäbisch Gmünd, Germany. The findings of the household survey illustrate the variety of damages caused by the heavy precipitation event and reveal important differences between households who experienced damages from pluvial flooding and those who did not. Lastly, findings of people’s perception about who is responsible for improved precautions offer interesting insights into tools that might help to enhance resilience building. Finally, the paper formulates recommendations for an improved assessment of resilience-building processes, individual capacities and planning tools to build climate resilience to extreme precipitation events.

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Precipitation in the Waikato River Catchment

10.26686/wgtn.16959397.v1 ◽

2021 ◽

Author(s):

◽

Stacey Maree Dravitzki

Keyword(s):

Observational Data ◽

Extreme Precipitation ◽

Numerical Models ◽

Heavy Precipitation ◽

Convective Precipitation ◽

River Catchment ◽

Synoptic Conditions ◽

Light Precipitation ◽

Precipitation Events ◽

Waikato River

<p>Observational data and numerical models were used to investigate precipitation in and around the Waikato River catchment. This economically important catchment relies on a dependable precipitation supply for agriculture and hydroelectric generation, with stations generally receiving 2,000 +/- 300 mm of precipitation annually. Long-term and inter-annual variability of total and extreme precipitation were examined using up to 100 years of observational data. Precipitation volumes within the catchment were represented by a five-day smoothed, area-averaged time series, and extreme events were defined as exceeding the 95th percentile. Atmospheric circulation oscillations correlated with the frequency of light precipitation but not with the probability of occurrence or with the magnitude of heavy precipitation events. Also no significant linear variations in precipitation (either annual totals or extreme precipitation characteristics) were found over this period, although temperature increased by 1.15+/-0.45'. A total of 63 heavy precipitation events were identified between 1996 and 2001. An analysis of the prevailing synoptic conditions reveal that heavy precipitation was associated with the passage of cold fronts of cyclones with minima at both 500 and 1000 mb heights. Extended periods of enhanced baroclinicity (succession of cyclones) or blocking anticyclones east of New Zealand have led to flooding in the Waikato catchment. Storm tracking showed that 10% of cyclones originating in the Tasman Sea result in heavy precipitation in the catchment. The accuracy and value of the GFS global precipitation forecasts <= 180 hours were investigated. Depending on forecast lag, the global models correctly predicted the presence of precipitation in 70-80% of forecasts, but the magnitude and distribution were often inaccurate. The probability of receiving precipitation is increased when more members of a lagged ensemble predict it. Forecasts with lags shorter than approximately 96 hours were appropriate to use as boundary constraints for mesoscale modelling. The ability and limitations of mesoscale models to simulate the spatial distribution of precipitation were examined through high-resolution WRF simulations of three heavy precipitation events, and ten different model settings were compared for the January 2006 event. The model consistently under-predicted precipitation. The timing and location of convective precipitation, which accounted for 50% of the precipitation during two events, was physically unconstrained but regional totals were comparable to observations. A continuous two-year numerical simulation was run to provide a precipitation climatology for data-sparse areas. The simulation gave good spatial representation of precipitation and other meteorological variables but tended to under estimate the magnitude of heavy precipitation and over-estimate light precipitation.</p>

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Precipitation in the Waikato River Catchment

10.26686/wgtn.16959397 ◽

2021 ◽

Author(s):

◽

Stacey Maree Dravitzki

Keyword(s):

Observational Data ◽

Extreme Precipitation ◽

Numerical Models ◽

Heavy Precipitation ◽

Convective Precipitation ◽

River Catchment ◽

Synoptic Conditions ◽

Light Precipitation ◽

Precipitation Events ◽

Waikato River

<p>Observational data and numerical models were used to investigate precipitation in and around the Waikato River catchment. This economically important catchment relies on a dependable precipitation supply for agriculture and hydroelectric generation, with stations generally receiving 2,000 +/- 300 mm of precipitation annually. Long-term and inter-annual variability of total and extreme precipitation were examined using up to 100 years of observational data. Precipitation volumes within the catchment were represented by a five-day smoothed, area-averaged time series, and extreme events were defined as exceeding the 95th percentile. Atmospheric circulation oscillations correlated with the frequency of light precipitation but not with the probability of occurrence or with the magnitude of heavy precipitation events. Also no significant linear variations in precipitation (either annual totals or extreme precipitation characteristics) were found over this period, although temperature increased by 1.15+/-0.45'. A total of 63 heavy precipitation events were identified between 1996 and 2001. An analysis of the prevailing synoptic conditions reveal that heavy precipitation was associated with the passage of cold fronts of cyclones with minima at both 500 and 1000 mb heights. Extended periods of enhanced baroclinicity (succession of cyclones) or blocking anticyclones east of New Zealand have led to flooding in the Waikato catchment. Storm tracking showed that 10% of cyclones originating in the Tasman Sea result in heavy precipitation in the catchment. The accuracy and value of the GFS global precipitation forecasts <= 180 hours were investigated. Depending on forecast lag, the global models correctly predicted the presence of precipitation in 70-80% of forecasts, but the magnitude and distribution were often inaccurate. The probability of receiving precipitation is increased when more members of a lagged ensemble predict it. Forecasts with lags shorter than approximately 96 hours were appropriate to use as boundary constraints for mesoscale modelling. The ability and limitations of mesoscale models to simulate the spatial distribution of precipitation were examined through high-resolution WRF simulations of three heavy precipitation events, and ten different model settings were compared for the January 2006 event. The model consistently under-predicted precipitation. The timing and location of convective precipitation, which accounted for 50% of the precipitation during two events, was physically unconstrained but regional totals were comparable to observations. A continuous two-year numerical simulation was run to provide a precipitation climatology for data-sparse areas. The simulation gave good spatial representation of precipitation and other meteorological variables but tended to under estimate the magnitude of heavy precipitation and over-estimate light precipitation.</p>

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Modeling extreme precipitation over East China with a global variable-resolution modeling framework (MPASv5.2): Impacts of resolution and physics

10.5194/gmd-2018-340 ◽

2019 ◽

Author(s):

Chun Zhao ◽

Mingyue Xu ◽

Yu Wang ◽

Meixin Zhang ◽

Jianping Guo ◽

...

Keyword(s):

Extreme Precipitation ◽

Heavy Precipitation ◽

Cloud Microphysics ◽

Horizontal Resolution ◽

East China ◽

Precipitation Event ◽

Modeling Framework ◽

Variable Resolution ◽

Global Variable ◽

Physics Parameterizations

Abstract. The non-hydrostatic atmospheric Model for Prediction Across Scales (MPAS-A), a global variable-resolution modeling framework, is applied at a range of resolutions from hydrostatic (60 km, 30 km, 16 km) to non-hydrostatic (4 km) scales using regional refinement over East Asia to simulate an extreme precipitation event during 25–27 June 2012 over East China. The simulations are evaluated using ground observations and reanalysis data. The simulated distribution and intensity of precipitation are analyzed to investigate the sensitivity to model configuration, resolution, and physics parameterizations. In general, simulations using global uniform-resolution and variable-resolution meshes share similar characteristics of precipitation and wind in the refined region with comparable horizontal resolution. Further experiments at multiple resolutions reveal the significant impacts of horizontal resolution on simulating the distribution and intensity of precipitation and updrafts. More specifically, simulations at coarser resolutions shift the zonal distribution of the rainbelt and produce weaker heavy-precipitation centers that are misplaced relative to the observed locations. In comparison, simulations employing 4 km cell spacing produce more realistic features of precipitation and wind. Sensitivity experiments show that cloud microphysics have significant effects on modeling precipitation at non-hydrostatic scales, but their impacts are negligible compared to that of convective parameterizations for simulations at hydrostatic scales. This study provides the first evidence supporting the use of convection-permitting global variable-resolution simulations for studying and improving forecasting of extreme precipitation over East China, and motivates the need for a more systematic study of heavy precipitation events and impacts of physics parameterizations and topography in the future.

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An extreme precipitation event in Central Norway

Tellus A Dynamic Meteorology and Oceanography ◽

10.3402/tellusa.v63i4.15856 ◽

2011 ◽

Author(s):

Birthe Marie Steensen ◽

Haraldur Ã“lafsson ◽

Marius O. Jonassen

Keyword(s):

Extreme Precipitation ◽

Extreme Precipitation Event ◽

Precipitation Event

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Assimilating X- and S-Band Radar Data for a Heavy Precipitation Event in Italy

Water ◽

10.3390/w13131727 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1727

Author(s):

Valerio Capecchi ◽

Andrea Antonini ◽

Riccardo Benedetti ◽

Luca Fibbi ◽

Samantha Melani ◽

...

Keyword(s):

Extreme Event ◽

Wrf Model ◽

Heavy Precipitation ◽

Radar Data ◽

Flash Floods ◽

Precipitation Event ◽

Weather Research And Forecasting ◽

Limited Area ◽

Heavy Precipitation Event ◽

The Town

During the night between 9 and 10 September 2017, multiple flash floods associated with a heavy-precipitation event affected the town of Livorno, located in Tuscany, Italy. Accumulated precipitation exceeding 200 mm in two hours was recorded. This rainfall intensity is associated with a return period of higher than 200 years. As a consequence, all the largest streams of the Livorno municipality flooded several areas of the town. We used the limited-area weather research and forecasting (WRF) model, in a convection-permitting setup, to reconstruct the extreme event leading to the flash floods. We evaluated possible forecasting improvements emerging from the assimilation of local ground stations and X- and S-band radar data into the WRF, using the configuration operational at the meteorological center of Tuscany region (LaMMA) at the time of the event. Simulations were verified against weather station observations, through an innovative method aimed at disentangling the positioning and intensity errors of precipitation forecasts. A more accurate description of the low-level flows and a better assessment of the atmospheric water vapor field showed how the assimilation of radar data can improve quantitative precipitation forecasts.

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Simulation of Extreme Precipitation in Four Climate Regions in China by General Circulation Models (GCMs): Performance and Projections

Water ◽

10.3390/w13111509 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1509

Author(s):

Mengru Zhang ◽

Xiaoli Yang ◽

Liliang Ren ◽

Ming Pan ◽

Shanhu Jiang ◽

...

Keyword(s):

Extreme Precipitation ◽

General Circulation ◽

Global Climate ◽

Summer Precipitation ◽

General Circulation Models ◽

Cumulative Distribution ◽

Extreme Precipitation Events ◽

Increasing Trend ◽

The Future ◽

Semi Arid

In the context of global climate change, it is important to monitor abnormal changes in extreme precipitation events that lead to frequent floods. This research used precipitation indices to describe variations in extreme precipitation and analyzed the characteristics of extreme precipitation in four climatic (arid, semi-arid, semi-humid and humid) regions across China. The equidistant cumulative distribution function (EDCDF) method was used to downscale and bias-correct daily precipitation in eight Coupled Model Intercomparison Project Phase 5 (CMIP5) general circulation models (GCMs). From 1961 to 2005, the humid region had stronger and longer extreme precipitation compared with the other regions. In the future, the projected extreme precipitation is mainly concentrated in summer, and there will be large areas with substantial changes in maximum consecutive 5-day precipitation (Rx5) and precipitation intensity (SDII). The greatest differences between two scenarios (RCP4.5 and RCP8.5) are in semi-arid and semi-humid areas for summer precipitation anomalies. However, the area of the four regions with an increasing trend of extreme precipitation is larger under the RCP8.5 scenario than that under the RCP4.5 scenario. The increasing trend of extreme precipitation in the future is relatively pronounced, especially in humid areas, implying a potential heightened flood risk in these areas.

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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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