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Die Messung der Zunahme der Meeresspiegels. Exkurs: Salz-Verklappung auf hoher See. Dr. Ingo Sasgen Alfred-Wegener-Institut (AWI), Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven. 13. Juni 2019, 14:30 Uhr, Bayerischer Hof, München. Alfred-Wegener-Institute.
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Die Messung der Zunahme der Meeresspiegels Exkurs: Salz-Verklappung auf hoher See Dr. Ingo Sasgen Alfred-Wegener-Institut (AWI), Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven 13. Juni 2019, 14:30 Uhr, Bayerischer Hof, München
Alfred-Wegener-Institute 3 Antarcticstations 2Arcticstations 2 polar aircrafts ca. 1100 employees 5 research vessels Slide 1
Processes causing sea-level rise Controlled by complex ice-sheet dynamic processes Land ~ 2/3 Addition of water Melting of continental ice Oceanmass Sea-level rise Global warming +ΔT Volume expansion Warming of ocean Oceanvolume ~ 1/3 Direct effect Slide 2
Satellite measurements of sea-level rise Mass on continents and in ocean GRACE/GRACE-FO Satellite observations Land Height of the sea surface Addition of water Oceanmass Ocean altimetry Satellite observations *2002 Temperature and salinity of ocean * 1992 Argo FloatsIn situ network Volume expansion Oceanvolume * 2005 * Start of data availability Slide 3
Components of sea-level rise Time period:2005 to 2017 Source: WCRP Global Sea Level Budget Group https://doi.org/10.5194/essd-10-1551-2018 cm / decade Total overocean(GRACE+Argo) Total(Altimetry) Sumofsources(main) 3.5 Terrestrial Terrestrial Volume expansion Antarctica Antarctica cm / decade Greenland Greenland Addition ofwater Glaciers Glaciers Expansion Slide 4
Long-term trends of sea-level rise Method 1: Coupled climate models: based on physics Projections Width of possible scenarios (state 2013, RCP8.5) Method 2: Probabilistic projection: based on data correlations Time (years) Tide-gauge measurements since 1880 Method 3: Expert elicitation: Accounts for high end probabilities and limited knowledge Paleo data Satellite measurements since 1992 Year Source: IPCC 2013 Figure 13.27, S. 1204 Slide 5
Probabilistic sea-level projection (year 2100) Scenario: RCP8.5 “business as usual” Partial collapse? Cuxhaven, Northern Germany Method 2 Limited Underest. Sea-level change wrt. 2005 (cm) ~CO2 ??? Source: Jevrejeva et al. 2016, Doi: 10.1073/pnas.1605312113 Slide 6
Projections beyond the year 2100 Sea-level change (m) 2100 2200 2300 2400 2500 Year Source: IPCC 2013 Figure 13.13, S. 1188 Slide 7
Excursion: Salt disposal at open sea Deep water formation Ocean water: ca. 35 kg salt per ton of water Ideal place of salt disposal? Melting in Greenland Freshwater inflow Weakening of thermohaline circulation (e.g gulf stream) Deep water formation Source: https://www.pik-potsdam.de/institut/querverbindungen/hochschulen/images/thc-world-ocean-review.jpg/image_view_fullscreen Slide 8
Dr. Ingo Sasgen Alfred-Wegener-Institut (AWI), Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven
Deutlicher Anstieg des Meeresspiegels während der letzten 15 Jahre! [http://climateadaptation.hawaii.gov/sea-level-rise/]
Components of sea-level rise Slide 3 Tapley et al. 2019, accepted, Section Global MeanSea-level Data: Don Chambers, Univ. Florida
Source: https://diercke.westermann.de/content/weltmeere-wasserzirkulation-978-3-14-100700-8-232-1-0