Sensitivity of the WRF model to the lower boundary in an extreme precipitation event – Madeira island case study

Abstract. The advances in satellite technology in recent years have made feasible the acquisition of high-resolution information on the Earth's surface. Examples of such information include elevation and land use, which have become more detailed. Including this information in numerical atmospheric models can improve their results in simulating lower boundary forced events, by providing detailed information on their characteristics. Consequently, this work aims to study the sensitivity of the weather research and forecast (WRF) model to different topography as well as land-use simulations in an extreme precipitation event. The test case focused on a topographically driven precipitation event over the island of Madeira, which triggered flash floods and mudslides in the southern parts of the island. Difference fields between simulations were computed, showing that the change in the data sets produced statistically significant changes to the flow, the planetary boundary layer structure and precipitation patterns. Moreover, model results show an improvement in model skill in the windward region for precipitation and in the leeward region for wind, in spite of the non-significant enhancement in the overall results with higher-resolution data sets of topography and land use.

Download Full-text

Sensitivity of the WRF model to the lower boundary in an extreme precipitation event – Madeira Island case study

Natural Hazards and Earth System Sciences Discussions ◽

10.5194/nhessd-1-5603-2013 ◽

2013 ◽

Vol 1 (5) ◽

pp. 5603-5641 ◽

Cited By ~ 2

Author(s):

J. C. Teixeira ◽

A. C. Carvalho ◽

T. Luna ◽

A. Rocha

Keyword(s):

Land Use ◽

Extreme Precipitation ◽

Lower Boundary ◽

Wrf Model ◽

Forecast Model ◽

Extreme Precipitation Event ◽

Precipitation Event ◽

Test Case ◽

Madeira Island

Abstract. Through the years, the advances in satellite technology made feasible the acquisition of information about the Earth surface, such as elevation and land use with great detail and resolution. This information can be included in numerical atmospheric models, updating them and providing a more detailed lower boundary, which in turn can improve the results of events forced by it. Given this, this work aims to study the sensitivity of the Weather Research and Forecast model to three different topography datasets as well as two different land use datasets in an extreme precipitation event. A test case study in which topography driven precipitation was dominant over Madeira Island was considered which triggered several flash floods and mudslides in the southern parts of the island. Model results show higher model skill in precipitation over Madeira leeward and in the windward wind flow, in spite of the non significant enhancement on the overall results with higher resolution datasets of topography and land use.

Download Full-text

Modelling the extreme precipitation event over Madeira Island on 20 February 2010

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-2437-2011 ◽

2011 ◽

Vol 11 (9) ◽

pp. 2437-2452 ◽

Cited By ~ 26

Author(s):

T. Luna ◽

A. Rocha ◽

A. C. Carvalho ◽

J. A. Ferreira ◽

J. Sousa

Keyword(s):

Extreme Precipitation ◽

Extreme Event ◽

Wrf Model ◽

Weather Conditions ◽

Horizontal Resolution ◽

Extreme Precipitation Event ◽

Cumulus Parameterization ◽

Precipitation Event ◽

Madeira Island ◽

Strong Winds

Abstract. In the morning of the 20 February of 2010 an extreme precipitation event occurred over Madeira Island. This event triggered several flash floods and mudslides in the southern parts of the island, resulting in 42 confirmed deaths, 100 injured, and at least 8 people still missing. These extreme weather conditions were associated to a weather frontal system moving northeastwards embedded in a low pressure area centered in the Azores archipelago. This storm was one in a series of such storms that affected Portugal, Spain, Morocco and the Canary islands causing flooding and strong winds. These storms were bolstered by an unusually strong sea surface temperature gradient across the Atlantic Ocean. In this study, the WRF model is used to evaluate the intensity and predictability of this precipitation extreme event over the island. The synoptic/orographic nature of the precipitation is also evaluated, as well as the sensitivity of the model to horizontal resolution and cumulus parameterization. Orography was found to be the main factor explaining the occurrence, amplitude and phase of precipitation over the Island.

Download Full-text

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

Download Full-text

Response of a mixed grass prairie to an extreme precipitation event

Ecosphere ◽

10.1890/es15-00073.1 ◽

2015 ◽

Vol 6 (10) ◽

pp. art172 ◽

Cited By ~ 11

Author(s):

Amy L. Concilio ◽

Janet S. Prevéy ◽

Peter Omasta ◽

James O'Connor ◽

Jesse B. Nippert ◽

...

Keyword(s):

Extreme Precipitation ◽

Extreme Precipitation Event ◽

Precipitation Event ◽

Mixed Grass Prairie ◽

Mixed Grass

Download Full-text

An investigation of convective features and Z-R relationships for a local extreme precipitation event

Atmospheric Research ◽

10.1016/j.atmosres.2020.105372 ◽

2021 ◽

Vol 250 ◽

pp. 105372

Author(s):

Zhilin Zeng ◽

Donghai Wang ◽

Yun Chen

Keyword(s):

Extreme Precipitation ◽

Extreme Precipitation Event ◽

Precipitation Event ◽

Local Extreme

Download Full-text

Polarimetric Radar Signatures and Performance of Various Radar Rainfall Estimators during an Extreme Precipitation Event over the Thousand-Island Lake Area in Eastern China

Remote Sensing ◽

10.3390/rs11202335 ◽

2019 ◽

Vol 11 (20) ◽

pp. 2335 ◽

Cited By ~ 1

Author(s):

Yabin Gou ◽

Haonan Chen ◽

Jiafeng Zheng

Keyword(s):

Extreme Precipitation ◽

Rapid Development ◽

Eastern China ◽

Rain Gauge ◽

Extreme Precipitation Event ◽

Precipitation Event ◽

Distribution Data ◽

Lake Area ◽

Polarimetric Radar ◽

Radar Rainfall

Polarimetric radar provides more choices and advantages for quantitative precipitation estimation (QPE) than single-polarization radar. Utilizing the C-band polarimetric radar in Hangzhou, China, six radar QPE estimators based on the horizontal reflectivity (ZH), specific attenuation (AH), specific differential phase (KDP), and double parameters that further integrate the differential reflectivity (ZDR), namely, R(ZH, ZDR), R(KDP, ZDR), and R(AH, ZDR), are investigated for an extreme precipitation event that occurred in Eastern China on 1 June 2016. These radar QPE estimators are respectively evaluated and compared with a local rain gauge network and drop size distribution data observed by two disdrometers. The results show that (i) although R(AH, ZDR) underestimates in the light rain scenario, it performs the best among all radar QPE estimators according to the normalized mean error; (ii) the optimal radar rainfall relationship and consistency between radar measurements aloft and their surface counterparts are both required to obtain accurate rainfall estimates close to the ground. The contamination from melting layer on AH and KDP can make R(AH), R(AH, ZDR), R(KDP), and R(KDP, ZDR) less effective than R(ZH) and R(ZH,ZDR). Instead, adjustments of the α coefficient can partly reduce such impact and hence render a superior AH–based rainfall estimator; (iii) each radar QPE estimator may outperform others during some time intervals featured by particular rainfall characteristics, but they all tend to underestimate rainfall if radar fails to capture the rapid development of rainstorms.

Download Full-text