TY - GEN A1 - Kruse, Stefan A1 - Gerdes, Alexander A1 - Kath, Nadja J. A1 - Herzschuh, Ulrike T1 - Implementing spatially explicit wind-driven seed and pollen dispersal in the individual-based larch simulation model BT - LAVESI-WIND 1.0 T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - It is of major interest to estimate the feedback of arctic ecosystems to the global warming we expect in upcoming decades. The speed of this response is driven by the potential of species to migrate, tracking their climate optimum. For this, sessile plants have to produce and disperse seeds to newly available habitats, and pollination of ovules is needed for the seeds to be viable. These two processes are also the vectors that pass genetic information through a population. A restricted exchange among subpopulations might lead to a maladapted population due to diversity losses. Hence, a realistic implementation of these dispersal processes into a simulation model would allow an assessment of the importance of diversity for the migration of plant species in various environments worldwide. To date, dynamic global vegetation models have been optimized for a global application and overestimate the migration of biome shifts in currently warming temperatures. We hypothesize that this is caused by neglecting important fine-scale processes, which are necessary to estimate realistic vegetation trajectories. Recently, we built and parameterized a simulation model LAVESI for larches that dominate the latitudinal treelines in the northernmost areas of Siberia. In this study, we updated the vegetation model by including seed and pollen dispersal driven by wind speed and direction. The seed dispersal is modelled as a ballistic flight, and for the pollination of ovules of seeds produced, we implemented a wind-determined and distance-dependent probability distribution function using a von Mises distribution to select the pollen donor. A local sensitivity analysis of both processes supported the robustness of the model's results to the parameterization, although it highlighted the importance of recruitment and seed dispersal traits for migration rates. This individual-based and spatially explicit implementation of both dispersal processes makes it easily feasible to inherit plant traits and genetic information to assess the impact of migration processes on the genetics. Finally, we suggest how the final model can be applied to substantially help in unveiling the important drivers of migration dynamics and, with this, guide the improvement of recent global vegetation models. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 929 KW - long-distance dispersal KW - climate-change KW - genetic-structure KW - plant migration KW - larix-sibirica KW - DNA variation KW - large-scale KW - vegetation KW - landscape KW - future Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-445978 SN - 1866-8372 IS - 929 SP - 4451 EP - 4467 ER - TY - GEN A1 - Yamazaki, Yosuke A1 - Wendt, Vivien A1 - Miyoshi, Y. A1 - Stolle, Claudia A1 - Siddiqui, Tarique Adnan A1 - Kervalishvili, Guram N. A1 - Laštovička, J. A1 - Kozubek, M. A1 - Ward, W. A1 - Themens, D. R. A1 - Kristoffersen, S. A1 - Alken, Patrick T1 - September 2019 Antarctic sudden stratospheric warming BT - Quasi-6-Day wave burst and ionospheric effects T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - An exceptionally strong stationary planetary wave with Zonal Wavenumber 1 led to a sudden stratospheric warming (SSW) in the Southern Hemisphere in September 2019. Ionospheric data from European Space Agency's Swarm satellite constellation mission show prominent 6-day variations in the dayside low-latitude region at this time, which can be attributed to forcing from the middle atmosphere by the Rossby normal mode "quasi-6-day wave" (Q6DW). Geopotential height measurements by the Microwave Limb Sounder aboard National Aeronautics and Space Administration's Aura satellite reveal a burst of global Q6DW activity in the mesosphere and lower thermosphere during the SSW, which is one of the strongest in the record. The Q6DW is apparently generated in the polar stratosphere at 30-40 km, where the atmosphere is unstable due to strong vertical wind shear connected with planetary wave breaking. These results suggest that an Antarctic SSW can lead to ionospheric variability through wave forcing from the middle atmosphere. Plain Language Summary: A sudden stratospheric warming (SSW) is an extreme wintertime polar meteorological phenomenon occurring mostly over the Arctic region. Studies have shown that Arctic SSW can influence the entire atmosphere. In September 2019, a rare SSW event occurred in the Antarctic region, providing an opportunity to investigate its broader impact on the whole atmosphere. We present observations from the middle atmosphere and ionosphere during this event, noting unusually strong wave activity throughout this region. Our results suggest that an Antarctic SSW can have a significant impact on the whole atmosphere system similar to those due to Arctic events. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1394 KW - Rossby-normal modes KW - nonumiform background configuration KW - total electron-content KW - large-scale KW - planetary-waves KW - 5-day waves KW - equatorial electrojet KW - lower thermosphere KW - symmetric modes KW - 6.5-Day wave Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-515814 SN - 1866-8372 IS - 1 ER - TY - JOUR A1 - Yamazaki, Yosuke A1 - Wendt, Vivien A1 - Miyoshi, Y. A1 - Stolle, Claudia A1 - Siddiqui, Tarique Adnan A1 - Kervalishvili, Guram N. A1 - Laštovička, J. A1 - Kozubek, M. A1 - Ward, W. A1 - Themens, D. R. A1 - Kristoffersen, S. A1 - Alken, Patrick T1 - September 2019 Antarctic sudden stratospheric warming BT - Quasi-6-Day wave burst and ionospheric effects JF - Geophysical Research Letters N2 - An exceptionally strong stationary planetary wave with Zonal Wavenumber 1 led to a sudden stratospheric warming (SSW) in the Southern Hemisphere in September 2019. Ionospheric data from European Space Agency's Swarm satellite constellation mission show prominent 6-day variations in the dayside low-latitude region at this time, which can be attributed to forcing from the middle atmosphere by the Rossby normal mode "quasi-6-day wave" (Q6DW). Geopotential height measurements by the Microwave Limb Sounder aboard National Aeronautics and Space Administration's Aura satellite reveal a burst of global Q6DW activity in the mesosphere and lower thermosphere during the SSW, which is one of the strongest in the record. The Q6DW is apparently generated in the polar stratosphere at 30-40 km, where the atmosphere is unstable due to strong vertical wind shear connected with planetary wave breaking. These results suggest that an Antarctic SSW can lead to ionospheric variability through wave forcing from the middle atmosphere. Plain Language Summary: A sudden stratospheric warming (SSW) is an extreme wintertime polar meteorological phenomenon occurring mostly over the Arctic region. Studies have shown that Arctic SSW can influence the entire atmosphere. In September 2019, a rare SSW event occurred in the Antarctic region, providing an opportunity to investigate its broader impact on the whole atmosphere. We present observations from the middle atmosphere and ionosphere during this event, noting unusually strong wave activity throughout this region. Our results suggest that an Antarctic SSW can have a significant impact on the whole atmosphere system similar to those due to Arctic events. KW - Rossby-normal modes KW - nonumiform background configuration KW - total electron-content KW - large-scale KW - planetary-waves KW - 5-day waves KW - equatorial electrojet KW - lower thermosphere KW - symmetric modes KW - 6.5-Day wave Y1 - 2020 U6 - https://doi.org/10.1029/2019GL086577 SN - 0094-8276 SN - 1944-8007 VL - 47 IS - 1 SP - 1 EP - 12 PB - Wiley CY - Hoboken ER -