scholarly journals Damaging Convective and Non-Convective Winds in Southwestern Iberia during Windstorm Xola

Atmosphere ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 692
Author(s):  
Paulo Pinto ◽  
Margarida Belo-Pereira
Keyword(s):  
Cold Front ◽  
Economic Losses ◽  
Mainland Portugal ◽  
Wind Gusts ◽  
Front Structure ◽  
Bow Echo ◽  
Wind Events ◽  
Area North ◽  
Slantwise Convection ◽  
Jet Streak

On 23/12/2009, windstorm Xola struck mainland Portugal, causing serious damage in a small area north of Lisbon (Oeste region) and in the south region, inflicting economic losses of over EUR 100 million. In both areas, several power towers, designed to withstand up to 46 m s−1 winds, were destroyed. The causes of these two distinct damaging wind events were investigated. Xola was revealed to have a prominent cloud head and a split cold front structure. In the southern region, the damages were due to downburst winds, associated with a mesovortex, observed in a bow echo line triggered by an upper cold front. The cloud head presented several dry air intrusion signatures, co-located with tops progressively lowering towards the hooked tip. This tip revealed features consistent with the presence of slantwise convection, the descending branches of which may have been strengthened by evaporating cooling. At the reflectivity cloud head tip, a jet streak pattern was identified on weather radar, with Doppler velocities exceeding 55 m s−1, just 400 m above ground. This signature is coherent with the presence of a Sting jet, and this phenomenon was associated with the strongest wind gusts (over 40 m s−1) and the largest damages in the Oeste region.

scholarly journals A reconstruction of 1 August 1674 thunderstorms over the Low Countries

2017 ◽  
Vol 17 (2) ◽  
pp. 157-170 ◽  
Author(s):  
Gerard van der Schrier ◽  
Rob Groenland
Keyword(s):  
Large Scale ◽  
Cold Front ◽  
Return Time ◽  
Squall Line ◽  
Low Countries ◽  
Wind Gusts ◽  
Bow Echo ◽  
Event Based ◽  
The Impact ◽  
The City

Abstract. On 1 August 1674 an active cold front moved over the Low Countries. The accompanying thunderstorms along the squall line were abnormally active, leading to large-scale damage in Europe, from northern France to the northern parts of Holland where damages were particularly severe. Using reported and pictured observations of damages and modern meteorological concepts, the reconstruction of the storm points to an exceptionally severe squall line. The orientation and the velocity of the squall line are reconstructed and shows a developed bow-echo structure. An estimate of the strength of the strongest wind gusts is ≈ 55–90 m s−1 and is based on an assessment of the damages caused by this event. A rough estimate of the return time of this event, based on observed hail size, is between 1000 and 10 000 years. This storm is compared to a more recent storm which was similar in dynamics but much less devastating. Special attention is given to the city of Utrecht which was hit hardest, and where the impact of this storm is still recognizable in the cityscape.

scholarly journals Echinococcosis in Kurdistan Iraq: Prevalence of Cystic Hydatidosis in Man with a Survey of E.granulosus eggs in Stray Dogs in Kalar City, Sulaymania Province, Kurdistan- Iraq.

2019 ◽  
Vol 6 (1) ◽  
pp. 114-128
Author(s):  
Arkan Barzanji ◽  
Louis Saida
Keyword(s):  
Cystic Echinococcosis ◽  
Economic Losses ◽  
City Center ◽  
Stray Dogs ◽  
X Ray ◽  
Cystic Hydatidosis ◽  
Area North ◽  
One Year ◽  
Surgery Department ◽  
First Time

The current study included two levels: - cystic echinococcosis in man and a survey of eggs of the parasites E. granulosus in feces of stray dogs in Kalar city sulaymania province. The statically analysis of private and governmental hospitals documents showed 56 cases of cystic echinococcosis have been treated surgically during five years’ period (2013-2017). The patients who included in this study were examined by physicians and confirmed by one or more of the following methods, imaging diagnosis (CT scan, Ultrasound, and X ray), histopathology and serology. Among total of 3330 patients admitted to the surgery department of these hospitals, 56 (1, 6%) were found to be infected with cystic hydatidosis at approximately 5.6 cases per 100,000 persons and at average 11.2 cases per one year. Among total patients’ involvements, house wives 22 (39.28%) were high infected and then followed by the workers and students 12(21.4%) and 11(19.64%) respectively. According to the organs patients involvement liver was highly infected 31(55.3%) and then followed by lungs 9(16.07). The age group (41-50) yrs. was 13(23.21%) highly infected than other ages, and the females (53.57%) were high infected than males (46.4%) among total patients infected. The economic loses of 56 cases treated surgically was approximately 112000$ USA$. This study is the first time talking about economic losses in this city of Iraq. The result of 60 sample feces examination of stray dogs showed that 36.6% of which were contaminated with eggs of E. granulosus. The high percentage of infection with this parasite (60%), was found at the Slaughtered animal's area, south of city center and the lowest (10%) was at Awarakan, Jutyaran & sharawan2 area, north of city center.

scholarly journals Determining Criteria for Missed Events to Evaluate Significant Severe Convective Outlooks

2017 ◽  
Vol 32 (4) ◽  
pp. 1321-1328 ◽  
Author(s):  
Nathan M. Hitchens ◽  
Harold E. Brooks
Keyword(s):  
Severe Weather ◽  
Wind Gusts ◽  
Weather Events ◽  
Storm Prediction ◽  
Wind Events ◽  
Future Focus

Abstract Among the Storm Prediction Center’s (SPC) probabilistic convective outlook products are forecasts specifically targeted at significant severe weather: tornadoes that produce EF2 or greater damage, wind gusts of at least 75 mi h−1, and hail with diameters of 2 in. or greater. During the period of 2005–15, for outlooks issued beginning on day 3 and through the final update to the day 1 forecast, the accuracy and skill of these significant severe outlooks are evaluated. To achieve this, criteria for the identification of significant severe weather events were developed, with a focus on determining days for which outlooks were not issued, but should have been based on the goals of the product. Results show that significant tornadoes and hail are generally well identified by outlooks, but significant wind events are underforecast. There exist differences between verification measures when calculating them based on 1) only those days for which outlooks were issued and 2) days with outlooks or missed events; specifically, there were improvements in the frequency of daily skillful forecasts when disregarding missed events. With the greatest number of missed events associated with significant wind events, forecasts for this hazard are identified as an area of future focus for the SPC.

Assessing Integrated Earthquake Risk in OpenQuake with an Application to Mainland Portugal

2016 ◽  
Vol 32 (3) ◽  
pp. 1383-1403 ◽  
Author(s):  
Christopher G. Burton ◽  
Vitor Silva
Keyword(s):  
Risk Assessment ◽  
Assessment Tools ◽  
Social Characteristics ◽  
Economic Losses ◽  
Earthquake Risk ◽  
Damage Potential ◽  
Building Stock ◽  
Mainland Portugal ◽  
Risk Assessment Tools ◽  
Physical Risk

At the forefront of the risk assessment sciences is the development of standards, data, and tools for the assessment of earthquake risk. Countries such as Portugal have been targets of extensive earthquake risk assessments to communicate damage potential and to improve methodologies. Few studies, however, have gone beyond the estimation of direct physical impacts by integrating estimates of physical risk (i.e., human or economic losses) with quantified metrics of socioeconomic characteristics of populations. The purpose of this paper is to describe an end-to-end assessment of earthquake risk for mainland Portugal that accounts for physical and social attributes using the Global Earthquake Model's (GEM) suite of risk assessment tools. The results indicate that the potential adverse effects from earthquakes in Portugal are related to interacting conditions, some conditional on geography, some due to the characteristics of the building stock, and some having to do with the social characteristics of populations.

scholarly journals A reconstruction of the August 1st 1674 thunderstorms over Holland

2016 ◽  
Author(s):  
Gerard van der Schrier ◽  
Rob Groenland
Keyword(s):  
Large Scale ◽  
Cold Front ◽  
Return Time ◽  
Squall Line ◽  
Low Countries ◽  
Wind Speeds ◽  
Northern France ◽  
Bow Echo ◽  
The Impact ◽  
The City

Abstract. On August 1st 1674 an active cold front moved over the low countries. The accompanying thunderstorms along the squall line were abnormally active, leading to large-scale damage in Europe, from northern France to the northern parts of Holland where damages were particularly severe. Using reported and pictured observations of damages, a reconstruction of this storm is made and an interpretation using modern meteorological concepts is given. The velocity of this exceptionally severe squall line and its orientation, including a developed bow-echo structure, are reconstructed. An estimate of the wind speeds associated with this event and an estimate of the return time of this event is given. This storm is compared to a more recent storm which was similar in dynamics but much less devastating. Special attention is given to the city of Utrecht which was hit hardest, and where the impact of this storm is still recognisable in the cityscape.

scholarly journals Near-surface mean and gust wind speed in ERA5 across Sweden: towards an improved gust parametrization

2020 ◽  
Author(s):  
Lorenzo Minola ◽  
Fuqing Zhang ◽  
Cesar Azorin-Molina ◽  
Amir Ali Safaei Pirooz ◽  
Richard Flay ◽  
...  
Keyword(s):  
Wind Speed ◽  
Surface Wind ◽  
Surface Air Temperature ◽  
Surface Wind Speed ◽  
Economic Losses ◽  
Wind Gust ◽  
Reanalysis Dataset ◽  
Near Surface ◽  
Extreme Wind ◽  
Wind Events

<p>Driven by the twenty-century surface air temperature rise, extreme wind events could change in their frequency and magnitude of occurrence, with drastic impacts on human and ecosystems. As a matter of fact, windstorms and extreme wind conditions contribute to more than half of the economic losses associated with natural disasters in Europe. Across Scandinavia, the occurrence of wind gust events can affect aviation security, as well as damage buildings and forests, representing severe hazards to people, properties and transport. Comprehensive extreme wind datasets and analysis can help improving our understanding of these changes and help the society to cope with these changes. Unfortunately, due to the difficulty in measuring wind gust and the lack of homogeneous and continuous datasets across Sweden, it is challenging to assess and attribute their changes. Global reanalysis products represent a potential tool for assessing changes and impact of extreme winds, only if their ability in representing observed near-surface wind statistics can be demonstrated.</p><p>In this study the new ERA5 reanalysis product has been compared with hourly near-surface wind speed and gust observations across Sweden for 2013-2017. We found that ERA5 shows better agreement with both mean wind speed and gust measurements compared to the previous ERA-Interim reanalysis dataset. Especially across coastal regions, ERA5 has a closer agreement with observed climate statistics. However, significant discrepancies are still found for inland and high-altitude regions. Therefore, the gust parametrization used in ERA5 is further analyzed to better understand if the adopted gust formulation matches the physical processes behind the gust occurrence. Finally, an improved formulation of the gust parametrization is developed across Sweden and further tested for Norway, which is characterized by more complex topography.</p>

scholarly journals Maximum Wind Gusts Associated with Human-Reported Nonconvective Wind Events and a Comparison to Current Warning Issuance Criteria

2016 ◽  
Vol 31 (2) ◽  
pp. 451-465 ◽  
Author(s):  
Paul W. Miller ◽  
Alan W. Black ◽  
Castle A. Williams ◽  
John A. Knox
Keyword(s):  
Threshold Level ◽  
Daily Maximum ◽  
Eastern United States ◽  
High Wind ◽  
Maximum Wind ◽  
Wind Speeds ◽  
Wind Gusts ◽  
Historical Climatology ◽  
Wind Potential ◽  
Wind Events

Abstract Nonconvective high winds are a deceptively hazardous meteorological phenomenon. Though the National Weather Service (NWS) possesses an array of products designed to alert the public to nonconvective wind potential, documentation justifying the choice of issuance thresholds is scarce. Measured wind speeds from the Global Historical Climatology Network (GHCN)-Daily dataset associated with human-reported nonconvective wind events from Storm Data are examined in order to assess the suitability of the current gust criteria for the NWS wind advisory and high wind warning. Nearly 92% (45%) of the nonconvective wind events considered from Storm Data were accompanied by peak gusts beneath the high wind warning (wind advisory) threshold of 58 mi h−1 (25.9 m s−1) [46 mi h−1 (20.6 m s−1)], and greater than 74% (28%) of all fatal and injury-causing events were associated with peak gusts below these same product gust criteria. NWS wind products were disproportionately issued in areas of complex terrain where wind climatologies include a greater frequency of high wind warning threshold-level gusts, irrespective of observed impacts. For many areas of the eastern United States, a 58 mi h−1 (25.9 m s−1) gust of convective, tropical, or nonconvective origin falls within the top 0.5% of all observed daily maximum wind gusts, nearly eliminating the possibility of a nonconvective gust meeting the issuance criterion.

Sensitivity of Bow-Echo Simulation to Microphysical Parameterizations

2013 ◽  
Vol 28 (5) ◽  
pp. 1188-1209 ◽  
Author(s):  
Rebecca D. Adams-Selin ◽  
Susan C. van den Heever ◽  
Richard H. Johnson
Keyword(s):  
Weather Research And Forecasting ◽  
Cold Pools ◽  
Wind Gusts ◽  
Bow Echo ◽  
Mean Size ◽  
Echo Simulation ◽  
Fall Speed ◽  
Microphysical Parameterization ◽  
Peak Value

Abstract The sensitivity of a case study bow-echo simulation to eight different microphysical schemes in the Weather Research and Forecasting model was tested, with a focus on graupel parameter characteristics. The graupel parameter in one scheme was modified to have a larger mean size and faster fall speed to represent hail (“hail like”). The goal of the study was to measure the sensitivity of five parameters that are important to operational forecasters to graupel properties: timing of bowing development, system speed, wind gusts, system areal coverage, and accumulated precipitation. The time each system initiated bowing varied by as much as 105 min. Simulations containing graupel with smaller mean size and slower fall speed (“graupel like”) bowed earlier due to increased microphysical cooling and stronger cold pools. These same systems had reduced precipitation efficiency, producing a peak storm-total accumulation of 36 mm, compared to a hail-like peak value of 237 mm, and observed a peak value of 53 mm. Faster-falling hail-like hydrometeors reached the surface with minimal melting, producing the largest accumulations. Graupel-like systems had 10-m wind gusts 73% stronger compared to hail-like systems, due to stronger low-level downdrafts. Systems with a smaller mean graupel size were 19% faster, also due to increased microphysical cooling. The size of the convective region varied by 150%, although this was partially due to scheme differences other than the graupel parameter. The significant differences in bow-echo characteristics produced by graupel property variations in convective-resolving models emphasize careful microphysical parameterization design. These sensitivities have forecasting implications, as graupel characteristics vary depending on the ambient environment and other factors. Detailed observations of graupel properties are recommended.

scholarly journals Analysis of wind damages during 2009-2018 period in Basque Country

2021 ◽  
Author(s):  
Santiago Gaztelumendi
Keyword(s):  
Basque Country ◽  
Surface Wind ◽  
Temporal Distribution ◽  
High Impact ◽  
Economic Losses ◽  
Winter Period ◽  
Wind Gust ◽  
Pressure System ◽  
Cyclonic Storm ◽  
Wind Events

<p>Severe  weather  phenomena  impact  the  European  society  and economy  in  many  ways,  from disruption  in  various  sectors  and substantial  damages  in  infrastructure  to  human  and  economic losses.  Windstorms are amongst the most damaging natural hazards in Europe, with approximately 5 € billion of estimated annual losses in the EU.<strong> </strong></p><p>Economic losses from meteo-climatic hazards depend on the nature of the meteo-climatic severe event and on the vulnerability of exposed human assets to the particular hazard. In  this  work  we  focus  on  wind  damages  that  are  produced  when different meteorological conditions  promoted  high wind gust that affect human assets in a particular area.</p><p>In the Basque Country, wind impact episodes can occur during all the year, on one hand during summer session related with severe storms and coastal trapped disturbance and on the other during winter period mainly related with relatively deep pressure system affecting the territory. The latter are by far the ones that generate the events with the greatest impact, both in terms of their spatial extension and the amount of damage generated.</p><p>Here we present a characterization study of economic losses in Basque Country due to high impact wind events during a ten years period from 2009 to 2018. For this purpose we analyzed the “non-typical cyclonic storm”   damage   data   provided   by   the Spanish   Insurance Compensation Consortium (CCS) for the Basque Country area. 71.846 accepted claims corresponding to 189 days, affecting 251 municipalities, with a total amount of 83.6 million euros for the ten years period studied. We analyzed those data considering their typology and their spatial and temporal distribution. In order to extract some useful conclusions for further impact modeling, we include surface wind characteristics registered in the Automatic Weather Station (AWS)  Basque network. The final objective of this study is  to  contribute  in  reducing  the  knowledge  gaps  at  the  interface  between  available  local wind prediction/analysis systems and impact observed in Basque Country as a consequence of wind severe events.</p><p>The damages are distributed in 93 episodes, made up of one or more consecutive days with paid claims. The 21 high-impact episodes (more than 50 claims) account for 43% of the days with 99% of the claims and damages. In the 10 days of extreme impact (more than 1000 claims), which represent 5% of the days, 90% of the claims and 89% of the damages are recorded. The seasonal distribution of damage shows a clear winter pattern. Although the damage are produced throughout the territory, with different degree of impact in nearly all the municipalities,  there is a certain concentration in the three Basque capitals with 22% of the claims and 23% of the economic losses.</p>

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