Sonja Szymczak

• PhD
• Researcher at Deutsches Zentrum für Schienenverkehrsforschung

Heavy-rainfall events and associated natural hazards pose a major threat to rail transport and infrastructure. In this study, the correlation between heavy-rainfall events and three associated natural hazards was investigated using geographic information system (GIS) analyses and random-effects logistic models. The spatiotemporal linkage of a damag...

Tree fall onto railway lines puts passengers at risk and causes large economic losses due to disruption of train services and damage to infrastructure. Railway lines in Germany are vulnerable to tree fall because of the large number of trackside trees that exist in that country with approximately 70% of all railway lines being tree-lined. In this p...

Heavy rainfall events and associated natural hazards pose a major threat to rail transport and infrastructure. In this study, the correlation between heavy rainfall events and three associated natural hazards were investigated using GIS analyses and random-effects logistic models. The spatio-temporal linkage of a damage database of DB Netz AG and t...

Key message Black pine and Maritime pine exhibit considerable differences in growth phenology across elevation belts with a 1-month delay for xylogenesis and increasing growth rates from low, mid to high elevations. Abstract Investigating seasonal wood formation is crucial to understand tree growth responses to climate impact. The present study qu...

Gravitative Massenbewegungen stellen eine bedeutende Gefahrenquelle für die Sicherheit des Schienenverkehrs dar und können große ökonomische Schäden verursachen. Vor dem Hintergrund des Klimawandels und einer damit einhergehenden zunehmenden Häufigkeit von Massenbewegungen auslösenden Ereignissen ist es von großer Bedeutung, das Schienennetz resili...

The increased frequency and severity of drought events due to climate warming is negatively affecting tree radial growth, particularly in drought-prone regions, such as, e.g., the Mediterranean. In this climate change hotspot, populations of the same tree species may show different growth responses to climate, due to the great variety of microclima...

In contrast to river floods, the enormous erosion potential in catchments contributes significantly to the extent of damage to infrastructure in valleys. This paper investigates the impact of the heavy precipitation event of 14–15 July 2021 on the railroad in the Ahr valley in Rhineland-Palatinate, Germany. In a first step, a detailed overview of t...

Trees along railway networks represent a high risk due to their potential to fall during extreme weather events. The identification of locations along railway tracks with highest tree fall hazard is an important part of a proactive natural hazard management. A new user-friendly GIS tool (as ArcGIS toolbox) was developed that provides the opportunit...

Palaeoclimatic evidence is necessary to place the current warming and drying trends of the Mediterranean region in a long-term perspective of pre-industrial variability. Annually resolved and absolutely dated climate proxies that extend back into medieval times are, however, limited to a few sites only. Here we present a network of long ring width...

A crucial step in measuring the resilience of railway infrastructure is to quantify the extent of its vulnerability to natural hazards. In this paper, we analyze the vulnerability of the German railway network to four types of natural hazards that regularly cause disruptions in German rail operations: floods, mass movements, slope fires, and tree f...

Stem radial variations of Corsican Black pine (Pinus nigra Arnold subsp. laricio Maire) and Maritime pine (Pinus pinaster Aiton) were monitored to quantify the impact of two meteorologically contrasting consecutive years. On the French island of Corsica, in the western Mediterranean basin, the year 2017 was extremely dry, while 2018 was exceptional...

Maximum latewood density (MXD) measurements from long-lived Black pines (Pinus nigra spp. laricio) growing at the upper treeline in Corsica are one of the few archives to reconstruct southern European summer temperatures at annual resolution back into medieval times. Here, we present a compilation of five MXD chronologies from Corsican pines that c...

The French Mediterranean island of Corsica is already today confronted with a clear tendency towards water shortage, leading not only to socio-economical, but also to ecological problems. A potential, but not very widespread source of water is the presence of near-ground clouds, mostly fog. In this study, we investigate fog-low stratus (FLS) freque...

For climate models that use paleo-environment data to predict future climate change, tree-ring isotope variations are one important archive for the reconstruction of paleo-hydrological conditions. Due to the rather complicated pathway of water, starting from precipitation until its uptake by trees and the final incorporation of its components into...

Drought is a major factor limiting tree growth and plant vitality. In the Mediterranean region, the length and intensity of drought stress strongly varies with altitude and site conditions. We used electronic dendrometers to analyze the response of two native pine species to drought and precipitation events. The five study sites were located along...

Water availability is the most important factor for the vitality of forest ecosystems, especially in dry environments. The Mediterranean region is one of the hotspots of future climate change; therefore, data on the water cycle are urgently needed. We measured oxygen isotope compositions in creek water, precipitation, stem water, needle water, and...

Forest fires are an important factor shaping Mediterranean ecosystems and determine the distribution of different species. Information about past forest fires can be obtained with pyrodendroecology. Here, we present a fire history for three sites in the mountain forest belt on the island of Corsica in the Mediterranean Basin. The dating of scars fr...

Key message Intra-annual oxygen isotope patterns of tree-ring cellulose from Pinus nigra subsp. laricio and Pinus pinaster along an elevation gradient can be divided into four distinct patterns ((1) high values in the beginning of the tree ring, declining trend afterwards; (2) low values in the beginning, increasing trend afterwards; (3) high value...

In the ongoing scientific effort to improve the knowledge about climate change, paleoclimate proxies can provide crucial insights into past climatic conditions. This is especially important in the Mediterranean which is predicted to be strongly affected by climate change. Stable oxygen isotopes of tree rings can be used as one of those proxies but...

The mountainous island of Corsica in the western Mediterranean basin hosts Mediterranean as well as alpine ecosystems. It is highly affected by current climate change which manifests in an increasing number of heat waves and drought periods. These climate conditions can become crucial for the vitality of pine trees on the island. The interdisciplin...

The western Mediterranean basin is subject to ongoing climate change, exhibiting more pronounced drought periods during the growing season. Therein, the mountainous island of Corsica, France, was recently exposed to two extreme but strikingly different consecutive years: 2017 was especially dry and yielded a record minimum in annual precipitation w...

Located in the western Mediterranean basin, the island of Corsica (France) is expected to be strongly affected by climate change. With its diverse topography and altitudinal gradients from sea level to 2700 m asl, it hosts two pine species, i.e. Pinus pinaster in lower areas and P. nigra ssp. laricio in higher regions up to the upper tree line. How...

The mountainous island of Corsica in the western Mediterranean basin hosts Mediterranean as well as alpine ecosystems. It is highly affected by current climate change which manifests in an increasing number of heat waves and drought periods. The interdisciplinary bundle project CorsicArchive integrates dendroecological, climatological, and hydrolog...

Oxygen isotope ratios can serve as parameters for water-use efficiency and photosynthetic regulations when high-resolution (intra-annual) isotope chronologies are developed. Additionally, a better understanding of the reasons for small scale isotope variations is essential for a robust paleoclimatic interpretation of long-term tree-ring isotope var...

Oxygen isotope ratios in tree rings have been established as an important archive for palaeoclimatic research questions. Additionally, they can help to better understand tree physiological processes because they are influenced, beside the isotopic signature of source water, by fractionation processes in leaf water during transpiration, biochemical...

Der Mittelmeerraum gehört zu den Regionen, die mit am stärksten auf den Klimawandel reagieren und dessen Ökosysteme durch zunehmende Hitze- und Dürreperioden gefährdet sind. Um die klimatische Sensitivität der Vegetation auf vergangene und zukünftige Klimaänderungen analysieren zu können, integriert das Projekt „CorsicArchive - Alitudinal Gradients...

The Mediterranean is considered as an area which will be affected strongly by current climate change. However, temperature records for the past centuries which can contribute to a better understanding of future climate changes are still sparse for this region. We established a network of multi-century stable carbon isotope chronologies on Corsica t...

Stable carbon and oxygen isotopes in tree rings are considered as reliable climate archives as they provide past environmental information with high resolution. However, recent studies have shown that isotope chronologies may reveal a long-term age trend and be influenced by non-climatic factors as other tree-ring parameters as well. These trends c...

Stable isotopes in tree rings have widely been used for palaeoclimate reconstructions since tree rings record climatic information at annual resolution. However, various wood components or different parts of an annual tree-ring may differ in their isotopic compositions. Thus, sample preparation and subsequent laboratory analysis are crucial for the...

Debris flows and snow avalanches are common processes in the headwaters of steep watersheds worldwide. In forested areas, dendrogeomorphic analyses of trees affected by debris flows and snow avalanches have regularly been used to date past events. Previous studies have, however, almost never focused on both processes at once, as snow avalanche impa...