The Experts below are selected from a list of 34173 Experts worldwide ranked by ideXlab platform
Gianluca Franceschini - One of the best experts on this subject based on the ideXlab platform.
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global forest area disturbance from fire insect pests diseases and Severe Weather events
Forest Ecology and Management, 2015Co-Authors: Pieter Van Lierop, Erik Lindquist, Shiroma Sathyapala, Gianluca FranceschiniAbstract:Reliable global data on forest degradation and disturbances due to fire, insect pests, diseases and Severe Weather are important to understand ecosystem health and condition, safeguard production of goods and services and avoid negative impacts on human livelihoods. This paper presents a global analysis of forest area affected by fire, significant insect pest outbreaks, diseases and Severe Weather reported by countries as part of the Global Forest Resources Assessment 2015. Between 2003 and 2012, approximately 67 million hectares (1.7%) of forest land burned annually, mostly in tropical South America and Africa. In a similar reporting period, in total 142 million hectares of forest land were affected by other disturbances than fire. Insect pests affected more than 85 million hectares of forest, of which a major part was in temperate North America. Severe Weather disturbed over 38 million hectares, mostly in Asia. About 12.5 million hectares were reported to be disturbed by diseases, mostly in Asia and Europe. There were strong correlations between burned forest area and the area of partial canopy cover reduction, as well as between burned forest area and net forest loss. Partial canopy cover reduction is used as a proxy for forest degradation, although it also includes land under management that is not degraded. A decreasing trend in burned forest area was found, largely accounted for by decreased area burned within the last ten years in tropical South America. However, an increasing trend in burned forest area was found in the boreal climatic domain. The data on other disturbances was not suitable for determining any year on year correlations and should be improved in future data collection exercises.
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global forest area disturbance from fire insect pests diseases and Severe Weather events
Forest Ecology and Management, 2015Co-Authors: Pieter Van Lierop, Erik Lindquist, Shiroma Sathyapala, Gianluca FranceschiniAbstract:Reliable global data on forest degradation and disturbances due to fire, insect pests, diseases and Severe Weather are important to understand ecosystem health and condition, safeguard production of goods and services and avoid negative impacts on human livelihoods. This paper presents a global analysis of forest area affected by fire, significant insect pest outbreaks, diseases and Severe Weather reported by countries as part of the Global Forest Resources Assessment 2015. Between 2003 and 2012, approximately 67 million hectares (1.7%) of forest land burned annually, mostly in tropical South America and Africa. In a similar reporting period, in total 142 million hectares of forest land were affected by other disturbances than fire. Insect pests affected more than 85 million hectares of forest, of which a major part was in temperate North America. Severe Weather disturbed over 38 million hectares, mostly in Asia. About 12.5 million hectares were reported to be disturbed by diseases, mostly in Asia and Europe. There were strong correlations between burned forest area and the area of partial canopy cover reduction, as well as between burned forest area and net forest loss. Partial canopy cover reduction is used as a proxy for forest degradation, although it also includes land under management that is not degraded. A decreasing trend in burned forest area was found, largely accounted for by decreased area burned within the last ten years in tropical South America. However, an increasing trend in burned forest area was found in the boreal climatic domain. The data on other disturbances was not suitable for determining any year on year correlations and should be improved in future data collection exercises.
Pieter Groenemeijer - One of the best experts on this subject based on the ideXlab platform.
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frequency of Severe thunderstorms across europe expected to increase in the 21st century due to rising instability
npj Climate and Atmospheric Science, 2019Co-Authors: Anja T Radler, Pieter Groenemeijer, Eberhard Faust, Robert Sausen, Tomas PucikAbstract:We show that the frequency of damaging convective Weather events including lightning, hail and Severe wind gusts will likely increase over Europe until the end of this century. We apply a set of additive regression models to an ensemble of 14 regional climate simulations and find that convective instability will increase as a result of rising humidity near the earth’s surface. Even though a slight decrease in thunderstorm occurrence in southwestern and southeastern Europe is projected, the probability of Severe Weather will increase throughout Europe, in particular for very large hail. It might be expected that Arctic amplification would lead to a weaker jet stream and, thus lower vertical wind shear, but we find instead that the jet changes little or even increases in situations with convective instability. To cope with the rising hazard probabilities, risk models will need to be adapted, while investment in sturdier structures, like the use of hardened glass in greenhouses or solar panels, will become more cost-effective. Furthermore, the need will grow to advise the public on loss prevention by taking precautionary measures as storms approach. Damaging Weather events such as lightning, hail, and Severe wind gusts are likely to become more common across Europe over the next several decades. Increased global temperatures, high low-level humidity levels and a changing polar jet stream are all associated with anthropogenic climate change; however, the implications of such projected changes in relation to Severe Weather events are still being explored. Here, Anja Radler and colleagues use numerical simulations of regional climate to predict the severity and frequency of convective storms in Europe under projected anthropogenic climate conditions. They find that the probability of Severe Weather and thunderstorms are expected to increase throughout Europe, and in particular, very large hail is likely to become more common. Therefore, public warnings and precautionary measures and should be actioned as storms approach.
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a climatology of tornadoes in europe results from the european Severe Weather database
Monthly Weather Review, 2014Co-Authors: Pieter Groenemeijer, Thilo KuhneAbstract:AbstractA climatology of tornadoes (over land and water) is presented, based on the European Severe Weather Database (ESWD), which contains reports of 9529 tornadoes. With the exception of a few small countries, tornadoes have been reported from all regions of Europe. The highest density of tornado reports is in western and central Europe. ESWD tornado reports increased strongly from 1995 to 2006 as a result of increased data collection efforts, followed by a decrease that likely has a meteorological nature. There is strong underreporting in the Mediterranean region and eastern Europe. The daily cycle of tornadoes over land (sea) peaks between 1500 and 1600 (0900 and 1000) local time. The Mediterranean annual maximum is in autumn and winter, while regions farther north have a maximum in summer. In total, 822 tornado fatalities have been recorded in the ESWD, which include 10 tornadoes with more than 20 fatalities. The average annual number of tornado fatalities in Europe is estimated to be between 10 and ...
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overview of essl s Severe convective storms research using the european Severe Weather database eswd
Atmospheric Research, 2009Co-Authors: Nikolai Dotzek, Pieter Groenemeijer, B Feuerstein, Alois M HolzerAbstract:Abstract Severe thunderstorms constitute a major Weather hazard in Europe, with an estimated total damage of 5–8 billion euros each year nowadays. Even though there is an upward trend in damage due to increases in vulnerability and possibly also due to climate change impacts, a pan-European database of Severe thunderstorm reports in a homogeneous data format did not exist until a few years ago. The development of this European Severe Weather Database (ESWD) provided the final impetus for the establishment of the European Severe Storms Laboratory (ESSL) as a non-profit research organisation in 2006, after having started as an informal network in 2002. Our paper provides an overview of the first research results that have been achieved by ESSL. We start by outlining the reporting practice and quality-control procedure for the database, which has been enhanced by a major software upgrade in the fall of 2008. It becomes apparent that the state of reporting converges to a realistic description of the Severe storms climatology, corroborating, for instance, earlier estimates of tornado occurrence in Europe. Nevertheless, a further rise in the number of reported events must be expected, even without the presence of any physical trends. The European tornado and damaging wind intensity distributions as a function of the Fujita scale are quantitatively similar to long-term distributions from the USA, except for a strong underreporting of weak events (F0) that still persists in Europe. In addition, the ESSL has recently proposed a new wind speed scale, the Energy- or “ E -scale” which is linked to physical quantities and can be calibrated. Finally, we demonstrate the large potential of ESWD data use for forecast or nowcasting/warning verification purposes.
Alois M Holzer - One of the best experts on this subject based on the ideXlab platform.
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overview of essl s Severe convective storms research using the european Severe Weather database eswd
Atmospheric Research, 2009Co-Authors: Nikolai Dotzek, Pieter Groenemeijer, B Feuerstein, Alois M HolzerAbstract:Abstract Severe thunderstorms constitute a major Weather hazard in Europe, with an estimated total damage of 5–8 billion euros each year nowadays. Even though there is an upward trend in damage due to increases in vulnerability and possibly also due to climate change impacts, a pan-European database of Severe thunderstorm reports in a homogeneous data format did not exist until a few years ago. The development of this European Severe Weather Database (ESWD) provided the final impetus for the establishment of the European Severe Storms Laboratory (ESSL) as a non-profit research organisation in 2006, after having started as an informal network in 2002. Our paper provides an overview of the first research results that have been achieved by ESSL. We start by outlining the reporting practice and quality-control procedure for the database, which has been enhanced by a major software upgrade in the fall of 2008. It becomes apparent that the state of reporting converges to a realistic description of the Severe storms climatology, corroborating, for instance, earlier estimates of tornado occurrence in Europe. Nevertheless, a further rise in the number of reported events must be expected, even without the presence of any physical trends. The European tornado and damaging wind intensity distributions as a function of the Fujita scale are quantitatively similar to long-term distributions from the USA, except for a strong underreporting of weak events (F0) that still persists in Europe. In addition, the ESSL has recently proposed a new wind speed scale, the Energy- or “ E -scale” which is linked to physical quantities and can be calibrated. Finally, we demonstrate the large potential of ESWD data use for forecast or nowcasting/warning verification purposes.
Kristopher M Bedka - One of the best experts on this subject based on the ideXlab platform.
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comparison between goes 12 overshooting top detections wsr 88d radar reflectivity and Severe storm reports
Weather and Forecasting, 2012Co-Authors: Richard Dworak, Kristopher M Bedka, Jason Brunner, Wayne F FeltzAbstract:Studies have found that convective storms with overshooting-top (OT) signatures in Weather satellite imagery are often associated with hazardous Weather, such as heavy rainfall, tornadoes, damaging winds, and large hail. An objective satellite-based OT detection product has been developed using 11-mm infrared window (IRW) channel brightness temperatures (BTs) for the upcoming R series of the Geostationary Operational Environmental Satellite (GOES-R) Advanced Baseline Imager. In this study, this method is applied to GOES-12 IRW data and the OT detections are compared with radar data, Severe storm reports, and Severe Weather warnings over the eastern United States. The goals of this study are to 1) improve forecaster understanding of satellite OT signatures relative to commonly available radar products, 2) assess OT detection product accuracy, and 3) evaluate the utility of an OT detection product for diagnosing hazardous convective storms. The coevolution of radar-derived products and satellite OT signatures indicates that an OT often corresponds with the highest radar echo top and reflectivity maximum aloft. Validation of OT detections relative to composite reflectivity indicates an algorithm false-alarm ratio of 16%, with OTs within the coldest IRW BT range (,200 K) being the most accurate. A significant IRW BT minimum typically present with an OT is more often associated with heavy precipitation than a region with a spatially uniform BT. Severe Weather was often associated with OT detections during the warm season (April‐September) and over the southern United States. The Severe Weather to OT relationship increased by 15% when GOES operated in rapid-scan mode, showing the importance of high temporal resolution for observing and detecting rapidly evolving cloud-top features. Comparison of the earliest OT detection associated with a Severe Weather report showed that 75% of the cases occur before Severe Weather and that 42% of collocated SevereWeatherreportshadeitheranOTdetectedbeforeaSevereWeatherwarningor nowarningissuedat all. The relationships between satellite OT signatures, Severe Weather, and heavy rainfall shown in this paper suggest that 1) when an OT is detected, the particular storm is likely producing heavy rainfall and/or possibly Severe Weather; 2) an objective OT detection product can be used to increase situational awareness and forecaster confidence that a given storm is Severe; and 3) this product may be particularly useful in regions with insufficient radar coverage.
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overshooting cloud top detections using msg seviri infrared brightness temperatures and their relationship to Severe Weather over europe
Atmospheric Research, 2011Co-Authors: Kristopher M BedkaAbstract:Abstract This purposes of this paper are to: 1) demonstrate an objective overshooting top (OT) detection method using Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI) infrared data, 2) produce an OT database for all operational SEVIRI data over Europe and north Africa for the six Northern Hemisphere warm seasons observed by SEVIRI to date, and 3) determine the frequency of OT detections in the vicinity of confirmed Severe Weather reports recorded within the European Severe Weather Database (ESWD). Algorithm performance is demonstrated for a case where numerous Severe storms were present. Qualitative comparisons indicate that most OT detections correspond with the characteristic OT signature in SEVIRI 1 km resolution visible channel imagery, but some OTs were left undetected due in part to relatively coarse SEVIRI spatial resolution over the European domain. The SEVIRI OT database shows a strong relationship between OT maxima and regions with high terrain. OTs are found to occur more frequently during the day over land and during the night over water. Inter- and intra-seasonal variability in OT frequency and location are also shown. An OT was found near 47% of the confirmed ESWD events. The OT–Severe Weather relationship is strong for large hail (53%) and Severe wind (52%) events but relatively weak for tornado events (14%). The weak OT–tornado relationship may be related two factors: 1) low-level wind shear is found to be of greater importance than large CAPE and strong updrafts (i.e. OTs) in tornadic storm environments across Europe and 2) a weakening of the storm updraft and collapse of the OT region has been documented prior to tornado formation. The relatively strong overall OT–Severe Weather relationship suggests that OT detections can be used to increase forecaster confidence that a given storm is Severe, especially in regions where frequent, ground based Doppler Weather radar data is unavailable.
Thilo Kuhne - One of the best experts on this subject based on the ideXlab platform.
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a climatology of tornadoes in europe results from the european Severe Weather database
Monthly Weather Review, 2014Co-Authors: Pieter Groenemeijer, Thilo KuhneAbstract:AbstractA climatology of tornadoes (over land and water) is presented, based on the European Severe Weather Database (ESWD), which contains reports of 9529 tornadoes. With the exception of a few small countries, tornadoes have been reported from all regions of Europe. The highest density of tornado reports is in western and central Europe. ESWD tornado reports increased strongly from 1995 to 2006 as a result of increased data collection efforts, followed by a decrease that likely has a meteorological nature. There is strong underreporting in the Mediterranean region and eastern Europe. The daily cycle of tornadoes over land (sea) peaks between 1500 and 1600 (0900 and 1000) local time. The Mediterranean annual maximum is in autumn and winter, while regions farther north have a maximum in summer. In total, 822 tornado fatalities have been recorded in the ESWD, which include 10 tornadoes with more than 20 fatalities. The average annual number of tornado fatalities in Europe is estimated to be between 10 and ...
