Klimawandel in den Polargebieten Inhalt Peter Lemke Alfred-Wegener-Institut für Polar- und Meeresforschung Bremerhaven 1. Polargebiete 2. Arktis (& Antarktis) 3. Neumayer Institut für Umweltphysik Universität Bremen Inhalt Die Polargebiete Permafrost 1. Polargebiete 2. Arktis (& Antarktis) 3. Neumayer Eisschilde Meereis Klimasystem Hohe Albedo Latente Wärme Plastisches Material Effektiver Deckel Polargebiete Globales Klima Niedere Breiten sind Energie-Kollektoren Hohe Breiten sind Energie-Radiatoren Ausgleich durch Energietransport in Ozean und Atmosphäre Energietransport wird durch emperaturgegensätze Äquator Pol gesteuert
Polargebiete Globales Klima Meereis behindert den Wärmeaustausch Meereis ist eine wichtige Süßwasser-Quelle (Nord-Atlantik, Weddellmeer) und beeinflusst die globale ozeanische iefenzirkulation iefen- und Bodenwasserbildung Polargebiete Globales Klima Größte Erwärmung in CO2 Klimaszenarien in Polargebieten (Oberflächen-Energiebilanz; emperatur Eisalbedo Feedback) Polargebiete Globales Klima Inhalt Verstärkte Reaktion in Polargebieten GFDL model 12 models 1. Polargebiete 2. Arktis (& Antarktis) 3. Neumayer Erwärmung bei CO2 Verdopplung mit konstanter Albedo (FA) und mit Eis-Albedo Feedback (VA) (Hall, 2004) Erwärmung bei CO2 Verdopplung (Jahre 61-80) (Winton, 2006)
Global gemittelte emperaturen steigen schneller mit der Zeit Die wärmsten 13 Jahre: 1998,2005,2003,2002,2004,2006, 2001,2007,1997,1995,1999,1990,20 00 Meereis-Ausdehung NH rend: -2.7% pro Dekade Periode Rate 50 1000.1280.0 26 0.0740.0 18 Jahre C/Dekade SH rend: nicht signifikant emperaturen in den Polargebieten emperatur von Neumayer rend (letzten 50 Jahre) Arktis = 1,1 C global = 0,6 C? A Synthesis of Antarctic emperatures Warme Arktis kalte Antarktis Linear trends of annual mean surface temperature for the period 1958 and 2002 (Chapmann&Walsh,2005) Neumayer Farada y
Ocean emperatures in Fram Strait 1 9 9 7 Atlantic Water (>2 C) temperature measured by moorings and from summer CD sections ime (years ) Depth: 250m Based on monthly means 2 0 0 8 Arctic Minimum Sea Ice Extent Arctic Minimum Sea Ice Extent Summer Minimum Decline (-7.4% per decade) 2008 Sept 2007 1978 2007 Current Arctic Sea Ice Extent Airborne EM sea ice thickness sounding 30 November 2008 Formatvorlage des Untertitelmasters durch Klicken bearbeiten EM bird
{06162AEB-1572-44B8-AA58-7E83D52BA2BE} {35796FC2-4983-48AE-AAD6-FF9F54C7CA06} {CD0D59E3-7F75-48CD-8B6B-D262C1D1EB79} {661E4FDF-0C59-4ECA-8449-540904B8C5BB} {C2D3AFE7-85A0-48B7-8490-34E9647EB008} {C66EEEFB-2CF0-455B-8486-340E0E634009} {4F889437-29B4-4015-A7EC-96FB9CD7B1F7} {B5600C65-C727-46E9-9A6F-47AA25B8712D} {556D417A-2DB1-485C-898A-2DE1476232E1} {DB06D91E-9329-4840-81BC-5A09E3713DAE} EM induction sea ice thickness sounding 2004, 2007, 2005, 2003, 2008, 2006, 2009 2008 de M dlas er Zi = dem dlaser (snow + ice) Framstrait Central Baltic Beaufort Sea Artic/ranspolar Sea Lincoln Svalbard Sea Laptev drift S Formatvorlage des Untertitelmasters durch Klicken bearbeiten 2003, 2005, 1991, 2004, 2008 1996, 2005, 1998, 2007 2001, 2004, 2007 Ice << Sea t Ice thickness variability in the ranspolar Drift: 1991, 1996, 1998, 2001, 2004 & 2007 Sea Ice hickness Lincoln Sea 2004-2008 hinner Sea ice in the Lincoln Sea in May 2008 despite 2007 ice dynamics 2004 2007 Sea ice drift pattern 2007 Haas, 2004 Rabenstein, Hendricks,Leinweber, 2007 GREENICE (EU) CryoVEx Simulated Arctic Sea Ice Volume 1990-2007 Inhalt 1. Polargebiete 2. Arktis (& Antarktis) 3. Neumayer Rüdiger Gerdes (NAOSIM)
Neumayer im Ozonloch Neumayer Ozonprofile 2006 König-Langlo, AWI Zeit-Höhenschnitt von Ozon König-Langlo, AWI Stratosphärische Ozonabnahme Zunahme der Globalstrahlung? From Dimming to Brightening Decadal Changes in Solar Radiation at Earth s Surface Martin Wild et al. Science 308 2005 König-Langlo, AWI
LWD rend at Neumayer Sonnenscheindauer König-Langlo, AWI König-Langlo, AWI Sunshine Duration & no clouds detected rends bei Neumayer emperatur unverändert, Globalstrahlung steigt, Gegenstrahlung sinkt, Sonnenscheindauer steigt dramatisch, Wolken werden weniger, König-Langlo, AWI hese: Zirkulationsänderung in der Antarktis kompensiert Effekte der globalen König-Langlo, AWI Motivation Heavy Precipitation and Strong Wind Events on the Antarctic Plateau: Observations from Kohnen Station, Dronning Maud Land European Project for Ice Coring in Antarctica (EPICA) High precipitation and strong wind events significantly influence accumulation pattern on the Antarctic Plateau. Neumayer G. Birnbaum, J. Freitag, G. König-Langlo Alfred Wegener Institute for Polar and Marine Research, Bremerhaven Novo R. Brauner Deutscher Wetterdienst, Hamburg C. ijm-reijmer Institute for Marine and Atmospheric Research, Utrecht University Kohnen (75 S, 0 E, 2892 m) 2nd Antarctic Meteorological Observation, Modeling, and Forecasting Workshop, Rome, Italy, 26-28 June 2007
Synoptic classification of visually observed high precipitation events at Kohnen Station during summer campaigns from 2001 to 2006 Strong Wind Events Synoptic Classification Category I: Occluding fronts of eastward moving lows reach the plateau. Category II: Lows or secondary lows which form east of the Greenwich Meridian move to the west (retrograde movement) and frontal clouds influence the plateau. Category III: Large-scale lifting processes due to an upper air low west of Kohnen Station cause snowfall on the plateau. Frequency 61% of events 30% of events 9% of events Impact on snow surface structure Barchan Dune Birnbaum et al. (2006) Synoptic classification of strong wind events Category I: Lows which move first from the Antarctic Peninsula / northern Weddell Sea southeastwards to a position close to Neumayer and then continue moving to the east or northeast Pattern Frequency 42% of events Conclusions ypical synoptic mechanisms for the occurrence of high precipitation and strong wind events could be identified. Category II: Lows initially situated off the coast east of the Greenwich Meridian which move to the west (retrograde movement) along the shelf ice edge 14% of events Unexpected high number of events due to retrograde moving lows Category III: Lows which move from the Antarctic Peninsula / northern Weddell Sea southeastwards to a position close to Neumayer and become stationary there 12% of events Number of snow dunes formed per year and conserved in the firn could be explained by a combined analysis of atmospheric observations and model data. Category IV: Lows which move first from the Antarctic Peninsula / northern Weddell Sea southeastwards, then turn to southwest, and die close to Halley or the Filchner Ice Shelf 12% of events Period 1998-2006: 10 typical synoptic situations identified Vielen Dank für Ihre Aufmerksamkeit!