@article{Vogel2022,
  author    = {Vogel, Johannes},
  title     = {Drivers of phenological changes in southern Europe},
  series = {International Journal of Biometeorology},
  volume    = {66},
  journal   = {International Journal of Biometeorology},
  number    = {9},
  publisher = {Springer},
  address   = {New York},
  issn      = {0020-7128},
  doi       = {10.1007/s00484-022-02331-0},
  pages     = {1903 -- 1914},
  year      = {2022},
  abstract  = {The life cycle of plants is largely determined by climate, which renders phenological responses to climate change a highly suitable bioindicator of climate change. Yet, it remains unclear, which are the key drivers of phenological patterns at certain life stages. Furthermore, the varying responses of species belonging to different plant functional types are not fully understood. In this study, the role of temperature and precipitation as environmental drivers of phenological changes in southern Europe is assessed. The trends of the phenophases leaf unfolding, flowering, fruiting, and senescence are quantified, and the corresponding main environmental drivers are identified. A clear trend towards an earlier onset of leaf unfolding, flowering, and fruiting is detected, while there is no clear pattern for senescence. In general, the advancement of leaf unfolding, flowering and fruiting is smaller for deciduous broadleaf trees in comparison to deciduous shrubs and crops. Many broadleaf trees are photoperiod-sensitive; therefore, their comparatively small phenological advancements are likely the effect of photoperiod counterbalancing the impact of increasing temperatures. While temperature is identified as the main driver of phenological changes, precipitation also plays a crucial role in determining the onset of leaf unfolding and flowering. Phenological phases advance under dry conditions, which can be linked to the lack of transpirational cooling leading to rising temperatures, which subsequently accelerate plant growth.},
  language  = {en}
}
@article{VogelPatonAichetal.2021,
  author    = {Vogel, Johannes and Paton, Eva and Aich, Valentin and Bronstert, Axel},
  title     = {Increasing compound warm spells and droughts in the Mediterranean Basin},
  series = {Weather and climate extremes},
  volume    = {32},
  journal   = {Weather and climate extremes},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {2212-0947},
  doi       = {10.1016/j.wace.2021.100312},
  pages     = {14},
  year      = {2021},
  abstract  = {The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly - with an annual growth rates of 3.9 (3.5) \% for warm season (deseasonalised) compound events and 4.6 (4.4) \% for warm spells -, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.},
  language  = {en}
}
@misc{VogelPatonAichetal.2021,
  author    = {Vogel, Johannes and Paton, Eva and Aich, Valentin and Bronstert, Axel},
  title     = {Increasing compound warm spells and droughts in the Mediterranean Basin},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {1127},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-49629},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-496294},
  pages     = {16},
  year      = {2021},
  abstract  = {The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly - with an annual growth rates of 3.9 (3.5) \% for warm season (deseasonalised) compound events and 4.6 (4.4) \% for warm spells -, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.},
  language  = {en}
}