Klimasystem Polargebiete Globales Klima

Inhalt
Klimawandel in den Polargebieten
1.
Peter Lemke
2.
3.
Polargebiete
Arktis (& Antarktis)
Neumayer
Alfred-Wegener-Institut für Polar- und Meeresforschung
Bremerhaven
Institut für Umweltphysik
Universität Bremen
IPCC AR4
IPCC AR4
Inhalt
Die Polargebiete
Permafrost
Eisschilde
1.
2.
3.
Polargebiete
Arktis (& Antarktis)
Neumayer
Meereis
IPCC AR4
Klimasystem
Hohe Albedo
™
Latente Wärme
™
Plastisches Material
™
Effektiver Deckel
™
IPCC AR4
Polargebiete
Niedere Breiten sind Energie-Kollektoren
™
Hohe Breiten sind Energie-Radiatoren
™
Ausgleich durch Energietransport in Ozean und Atmosphäre
™
IPCC AR4
Globales Klima
™
Energietransport wird durch Temperaturgegensätze
Äquator – Pol gesteuert
IPCC AR4
Polargebiete
™
Globales Klima
Meereis behindert den Wärmeaustausch
Meereis ist eine wichtige Süßwasser-Quelle
die
(Nord-Atlantik, Weddellmeer) und beeinflusst
globale ozeanische
Tiefenzirkulation
IPCC AR4
IPCC AR4
Polargebiete
Tiefen- und Bodenwasserbildung
™
Globales Klima
Größte Erwärmung in CO2–Klimaszenarien in Polargebieten
(Oberflächen-Energiebilanz; Temperatur – Eisalbedo Feedback)
IPCC AR4
Polargebiete
IPCC AR4
Globales Klima
Inhalt
Verstärkte Reaktion in Polargebieten
GFDL model
12 IPCC AR4 models
1.
2.
3.
Erwärmung bei CO2 Verdopplung
mit konstanter Albedo (FA) und
mit Eis-Albedo Feedback (VA)
(Hall, 2004)
Polargebiete
Arktis (& Antarktis)
Neumayer
Erwärmung bei CO2 Verdopplung
(Jahre 61-80) (Winton, 2006)
IPCC AR4
IPCC AR4
Global gemittelte Temperaturen 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 Trend: -2.7% pro Dekade
Periode
50
Rate
1000.128 0.0
0.074 0.0
26
18
Jahre
IPCC AR4
C/Dekade
Temperaturen in den Polargebieten
SH Trend: nicht signifikant
IPCC AR4
Temperatur von Neumayer
Trend
(letzten 50 Jahre)
TArktis = 1,1°C
Tglobal = 0,6°C
IPCC AR4
A Synthesis of Antarctic Temperatures
Linear trends of annual mean
surface temperature for the
period 1958 and 2002
(Chapmann&Walsh,2005)
?
IPCC AR4
Warme Arktis – kalte Antarktis
Neumayer
Farada
y
IPCC AR4
IPCC AR4
Atlantic Water (T>2°C) temperature
measured by moorings and from summer CTD sections
Ocean Temperatures
in Fram Strait
1
9
9
7
Time
(years
)
Depth: 250m
Based on
monthly means
2
0
IPCC AR4 0
8
Arctic Minimum Sea Ice Extent
IPCC AR4
Arctic Minimum Sea Ice Extent
Summer Minimum Decline
(-7.4% per decade)
2008
1978
2007
Sept 2007
IPCC AR4
Current Arctic Sea Ice Extent
IPCC AR4
Airborne EM sea ice thickness sounding
30 November 2008
Formatvorlage des Untertitelmasters durch
Klicken bearbeiten
EM
bird
IPCC AR4
IPCC AR4
2004,
2007,
2005,
2003,
2008
2008,
2006,
2006
2009
2008
EM induction sea ice thickness sounding
{06162AEB -1572-44B 8-AA58-7E83D 52B A2B E}
Zi = dEM –
dLaser
dE
M
Ice <<
t
dLas
er
{C D 0D 59E3-7F75-48C D -8B 6B -D 262C 1D 1EB 79}
{C 2D 3AFE7-85A0-48B 7-8490-34E9647EB 008}
{C 66EEEFB -2C F0-455B -8486-340E0E634009}
{B 5600C 65-C 727-46E9-9A6F-47AA25B 8712D }
{556D 417A-2D B 1-485C -898A-2D E1476232E1}
Framstrait
Central
Baltic
Beaufort
Sea
Artic/Transpolar
Sea
Lincoln
Svalbard
Sea
Laptev
drift S
Formatvorlage des Untertitelmasters durch Klicken bearbeiten
(snow + ice)
{35796FC 2-4983-48AE-AAD 6-FF9F54C 7C A06}
{661E4FD F-0C 59-4EC A-8449-540904B 8C 5B B }
{4F889437-29B 4-4015-A7EC -96FB 9C D 7B 1F7}
2003,
2005,
1991,
2004,
2008
1996,
2005,
1998,
2007
2001, 2004, 2007
Sea
IPCC AR4
Ice thickness variability in the Transpolar Drift:
1991, 1996, 1998, 2001, 2004 & 2007
IPCC AR4
Sea Ice Thickness Lincoln Sea 2004 - 2008
Thinner Sea ice in
the Lincoln Sea in
May 2008 despite
2007 ice dynamics
2007
Sea ice drift
pattern 2007
2004
Haas, 2004
{D B 06D 91E-9329-4840-81B C -5A09E3713D AE}
Rabenstein, Hendricks,Leinweber,
2007
IPCC AR4
GREENICE
(EU)
CryoVEx
IPCC AR4
Inhalt
Simulated Arctic Sea Ice Volume 1990 - 2007
1.
2.
3.
Rüdiger Gerdes (NAOSIM)
IPCC AR4
Polargebiete
Arktis (& Antarktis)
Neumayer
Neumayer „im Ozonloch“
Neumayer
Ozonprofile 2006
IPCC AR4
König-Langlo,
AWI
IPCC AR4
Zeit-Höhenschnitt von Ozon
IPCC AR4
Stratosphärische Ozonabnahme
IPCC AR4
König-Langlo,
AWI
Zunahme der Globalstrahlung?
From Dimming to
Brightening
Decadal Changes in
Solar Radiation at
Earth´s Surface
Martin Wild et
al.
Science 308
2005
IPCC AR4
König-Langlo,
AWI
IPCC AR4
LWD Trend at Neumayer
Sonnenscheindauer
IPCC AR4
König-Langlo,
AWI
Sunshine Duration & no clouds detected
IPCC AR4
König-Langlo,
AWI
Trends bei Neumayer
Temperatur unverändert,
Globalstrahlung steigt,
Gegenstrahlung sinkt,
Sonnenscheindauer steigt dramatisch,
Wolken werden weniger,
IPCC AR4
König-Langlo,
AWI
These:
Zirkulationsänderung in der Antarktis
kompensiert Effekte der globalen
IPCC AR4
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
Novo
Alfred Wegener Institute for Polar and Marine Research, Bremerhaven
R. Brauner
Deutscher Wetterdienst, Hamburg
C. Tijm-Reijmer
Institute for Marine and Atmospheric Research, Utrecht University
2nd Antarctic Meteorological Observation, Modeling, and Forecasting Workshop, Rome, Italy, 26-28 June 2007
Kohnen (75°S, 0°E, 2892 m)
Strong Wind Events
Synoptic classification of visually observed high precipitation events
at Kohnen Station during summer campaigns from 2001 to 2006
Synoptic Classification
Frequency
Category I:
Occluding fronts of eastward moving lows reach the
plateau.
61% of events
Impact on snow surface structure
Barchan Dune
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.
30% of events
9% of events
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
Conclusions
T
T
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
Category III:
Lows which move from the Antarctic Peninsula /
northern Weddell Sea southeastwards to a position
close to Neumayer and become stationary there
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
Frequency
T
T
T T T
42% of events
14% of events
T
T
T
T
T
T
12% of events
12% of events
Period 1998-2006: 10 typical synoptic situations identified
Vielen Dank für Ihre Aufmerksamkeit!
IPCC AR4
¾
Typical synoptic mechanisms for the occurrence of high
precipitation and strong wind events could be identified.
¾
Unexpected high number of events due to retrograde moving lows
¾
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.