PROF. DR. JAN ESPER

GLOBALER KLIMAWANDELINDIKATOREN & WECHSELWIRKUNGEN

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CO2IndikatorenIPCCFeedback

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Luftbestandteile

Treibhauswirkung

Norilsk 4

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CO

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cent

ratio

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Carbon dioxide concentration at Mauna Loa ObservatoryAugust 29, 2019Latest CO2 reading

Full Record ending August 31, 2019

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Carbon dioxide concentration at Mauna Loa ObservatoryAugust 29, 2019Latest CO2 reading

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Paris 2015

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Paris 2015 Lima 2014

Doha 2012 Durban 2011 Cancun 2010

Bali 2007 Berlin 1995

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CO2IndikatorenIPCCFeedbackVon: Dirck Oppermann dirck.oppermann@me.com

Betreff: Klimawandel gibt es nicht, weil Deutschlands Schwimmbäder seit 100 Jahren immer am 15. September schließen.Datum: 5. September 2019 um 23:59

An: Dirck Oppermann dirck.oppermann@icloud.com

Klimawandel gibt es nicht, weil Deutschlands Schwimmbäder seit 100 Jahren immer am 15. September schließen.

So einfach ist die Beweis-Führung,

wenn man das (grüne) Brett vor dem Kopf entfernt.

Was ist das Schwerste von allem? Was dir das Leichteste dünket. Mit den Augen zu sehen, was vor den Augen dir lieget.

Goethe, X, 5, Xenien, Aus dem Nachlass S 275,

Zeile 86 CD-ROM Datenbank virtuelle Bibliothek

http://www.medizin.hhu.de/fileadmin/redaktion/Fakultaeten/Medizinische_Fakultaet/Studiendekanat/Dokumente/Medizin_Studium/Klinik/Lernziele/LZK_Mikroskopische_Anatomie.pdf

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T-Messung in veränderter Umgebung (Verstädterung) ist eine Unsicherheit.

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Urban heat island (UHI)

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Schneedecke(16. Januar 2012)

Northern Hemisphere spring snow cover

IPCC 2013

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Arctic summer sea ice extent

September 16, 2012

Minimum over past 30 years

IPCC 2013

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Minimum over past 30 years

IPCC 2013

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Global average sea level change

IPCC 2013

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Surface ocean CO2 and pH

IPCC 2013

20IPCC 2013

Global ocean surface pH

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Global average sea level change

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Cumulative emissions of CO2 and future non-CO2 radiative forcing determine the probability of limiting warming to 1.5°C

Billion tonnes CO2 per year (GtCO2/yr) Billion tonnes CO2 (GtCO2) Watts per square metre (W/m2)b) Stylized net global CO2 emission pathways d) Non-CO2 radiative forcing pathways

c) Cumulative net CO2 emissions

a) Observed global temperature change and modeled

responses to stylized anthropogenic emission and forcing pathways

Observed monthly global mean surface temperature

Estimated anthropogenic warming to date and likely range

Faster immediate CO2 emission reductions limit cumulative CO2 emissions shown in panel (c).

Maximum temperature rise is determined by cumulative net CO2 emissions and net non-CO2 radiative forcing due to methane, nitrous oxide, aerosols and other anthropogenic forcing agents.

Global warming relative to 1850-1900 (°C)

CO2 emissions decline from 2020 to reach net zero in 2055 or 2040

Cumulative CO2 emissions in pathways reaching net zero in 2055 and 2040

Non-CO2 radiative forcing reduced a"er 2030 or not reduced a"er 2030

1960

1980 2020 2060 2100 1980 2020 2060 2100 1980 2020 2060 2100

1980 2000 2020

2017

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1.0

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Likely range of modeled responses to stylized pathways

Faster CO2 reductions (blue in b & c) result in a higher probability of limiting warming to 1.5°C

No reduction of net non-CO2 radiative forcing (purple in d) results in a lower probability of limiting warming to 1.5°C

Global CO2 emissions reach net zero in 2055 while net non-CO2 radiative forcing is reduced a!er 2030 (grey in b, c & d)

SPM

Summary for Policymakers

8

Figure SPM.1 | Panel a: Observed monthly global mean surface temperature (GMST, grey line up to 2017, from the HadCRUT4, GISTEMP, Cowtan–Way, and NOAA datasets) change and estimated anthropogenic global warming (solid orange line up to 2017, with orange shading indicating assessed likely range). Orange dashed arrow and horizontal orange error bar show respectively the central estimate and likely range of the time at which 1.5°C is reached if the current rate of warming continues. The grey plume on the right of panel a shows the likely range of warming responses, computed with a simple climate model, to a stylized pathway (hypothetical future) in which net CO2 emissions (grey line in panels b and c) decline in a straight line from 2020 to reach net zero in 2055 and net non-CO2 radiative forcing (grey line in panel d) increases to 2030 and then declines. The blue plume in panel a) shows the response to faster CO2 emissions reductions (blue line in panel b), reaching net zero in 2040, reducing cumulative CO2 emissions (panel c). The purple plume shows the response to net CO2 emissions declining to zero in 2055, with net non-CO2 forcing remaining constant after 2030. The vertical error bars on right of panel a) show the likely ranges (thin lines) and central terciles (33rd – 66th percentiles, thick lines) of the estimated distribution of warming in 2100 under these three stylized pathways. Vertical dotted error bars in panels b, c and d show the likely range of historical annual and cumulative global net CO2 emissions in 2017 (data from the Global Carbon Project) and of net non-CO2 radiative forcing in 2011 from AR5, respectively. Vertical axes in panels c and d are scaled to represent approximately equal effects on GMST. {1.2.1, 1.2.3, 1.2.4, 2.3, Figure 1.2 and Chapter 1 Supplementary Material, Cross-Chapter Box 2 in Chapter 1}

CO2IndikatorenIPCCFeedback Jürg Luterbacher

Professor für KlimageographieJustus Liebig Universität, Giessen

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This chapter should be cited as:Masson-Delmotte, V., M. Schulz, A. Abe-Ouchi, J. Beer, A. Ganopolski, J.F. González Rouco, E. Jansen, K. Lambeck, J. Luterbacher, T. Naish, T. Osborn, B. Otto-Bliesner, T. Quinn, R. Ramesh, M. Rojas, X. Shao and A. Timmermann, 2013: Information from Paleoclimate Archives. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Coordinating Lead Authors:Valérie Masson-Delmotte (France), Michael Schulz (Germany)

Lead Authors:Ayako Abe-Ouchi (Japan), Jürg Beer (Switzerland), Andrey Ganopolski (Germany), Jesus Fidel González Rouco (Spain), Eystein Jansen (Norway), Kurt Lambeck (Australia), Jürg Luterbacher (Germany), Tim Naish (New Zealand), Timothy Osborn (UK), Bette Otto-Bliesner (USA), Terrence Quinn (USA), Rengaswamy Ramesh (India), Maisa Rojas (Chile), XueMei Shao (China), Axel Timmermann (USA)

Contributing Authors:Kevin Anchukaitis (USA), Julie Arblaster (Australia), Patrick J. Bartlein (USA), Gerardo Benito (Spain), Peter Clark (USA), Josefino C. Comiso (USA), Thomas Crowley (UK), Patrick De Deckker (Australia), Anne de Vernal (Canada), Barbara Delmonte (Italy), Pedro DiNezio (USA), Trond Dokken (Norway), Harry J. Dowsett (USA), R. Lawrence Edwards (USA), Hubertus Fischer (Switzerland), Dominik Fleitmann (UK), Gavin Foster (UK), Claus Fröhlich (Switzerland), Aline Govin (Germany), Alex Hall (USA), Julia Hargreaves (Japan), Alan Haywood (UK), Chris Hollis (New Zealand), Ben Horton (USA), Masa Kageyama (France), Reto Knutti (Switzerland), Robert Kopp (USA), Gerhard Krinner (France), Amaelle Landais (France), Camille Li (Norway/Canada), Dan Lunt (UK), Natalie Mahowald (USA), Shayne McGregor (Australia), Gerald Meehl (USA), Jerry X. Mitrovica (USA/Canada), Anders Moberg (Sweden), Manfred Mudelsee (Germany), Daniel R. Muhs (USA), Stefan Mulitza (Germany), Stefanie Müller (Germany), James Overland (USA), Frédéric Parrenin (France), Paul Pearson (UK), Alan Robock (USA), Eelco Rohling (Australia), Ulrich Salzmann (UK), Joel Savarino (France), Jan Sedláček (Switzerland), Jeremy Shakun (USA), Drew Shindell (USA), Jason Smerdon (USA), Olga Solomina (Russian Federation), Pavel Tarasov (Germany), Bo Vinther (Denmark), Claire Waelbroeck (France), Dieter Wolf-Gladrow (Germany), Yusuke Yokoyama (Japan), Masakazu Yoshimori (Japan), James Zachos (USA), Dan Zwartz (New Zealand)

Review Editors:Anil K. Gupta (India), Fatemeh Rahimzadeh (Iran), Dominique Raynaud (France), Heinz Wanner (Switzerland)

Information fromPaleoclimate Archives

383

IPCC 2013N O R T H E R NHEMISPHERE

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383

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This chapter should be cited as:Masson-Delmotte, V., M. Schulz, A. Abe-Ouchi, J. Beer, A. Ganopolski, J.F. González Rouco, E. Jansen, K. Lambeck, J. Luterbacher, T. Naish, T. Osborn, B. Otto-Bliesner, T. Quinn, R. Ramesh, M. Rojas, X. Shao and A. Timmermann, 2013: Information from Paleoclimate Archives. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Coordinating Lead Authors:Valérie Masson-Delmotte (France), Michael Schulz (Germany)

Lead Authors:Ayako Abe-Ouchi (Japan), Jürg Beer (Switzerland), Andrey Ganopolski (Germany), Jesus Fidel González Rouco (Spain), Eystein Jansen (Norway), Kurt Lambeck (Australia), Jürg Luterbacher (Germany), Tim Naish (New Zealand), Timothy Osborn (UK), Bette Otto-Bliesner (USA), Terrence Quinn (USA), Rengaswamy Ramesh (India), Maisa Rojas (Chile), XueMei Shao (China), Axel Timmermann (USA)

Contributing Authors:Kevin Anchukaitis (USA), Julie Arblaster (Australia), Patrick J. Bartlein (USA), Gerardo Benito (Spain), Peter Clark (USA), Josefino C. Comiso (USA), Thomas Crowley (UK), Patrick De Deckker (Australia), Anne de Vernal (Canada), Barbara Delmonte (Italy), Pedro DiNezio (USA), Trond Dokken (Norway), Harry J. Dowsett (USA), R. Lawrence Edwards (USA), Hubertus Fischer (Switzerland), Dominik Fleitmann (UK), Gavin Foster (UK), Claus Fröhlich (Switzerland), Aline Govin (Germany), Alex Hall (USA), Julia Hargreaves (Japan), Alan Haywood (UK), Chris Hollis (New Zealand), Ben Horton (USA), Masa Kageyama (France), Reto Knutti (Switzerland), Robert Kopp (USA), Gerhard Krinner (France), Amaelle Landais (France), Camille Li (Norway/Canada), Dan Lunt (UK), Natalie Mahowald (USA), Shayne McGregor (Australia), Gerald Meehl (USA), Jerry X. Mitrovica (USA/Canada), Anders Moberg (Sweden), Manfred Mudelsee (Germany), Daniel R. Muhs (USA), Stefan Mulitza (Germany), Stefanie Müller (Germany), James Overland (USA), Frédéric Parrenin (France), Paul Pearson (UK), Alan Robock (USA), Eelco Rohling (Australia), Ulrich Salzmann (UK), Joel Savarino (France), Jan Sedláček (Switzerland), Jeremy Shakun (USA), Drew Shindell (USA), Jason Smerdon (USA), Olga Solomina (Russian Federation), Pavel Tarasov (Germany), Bo Vinther (Denmark), Claire Waelbroeck (France), Dieter Wolf-Gladrow (Germany), Yusuke Yokoyama (Japan), Masakazu Yoshimori (Japan), James Zachos (USA), Dan Zwartz (New Zealand)

Review Editors:Anil K. Gupta (India), Fatemeh Rahimzadeh (Iran), Dominique Raynaud (France), Heinz Wanner (Switzerland)

Information fromPaleoclimate Archives

CO2IndikatorenIPCCFeedback

30

Wasserdampf

Treibhausgase

Erwärmung

Stärkere Verdunstung

Treibhausgase

Erwärmung

ZusätzlicheRückstrahlung

Albedo CO2 Lösung

EisrückgangArktis

ReduzierteReflexion

Treibhausgase

Erwärmung(Ozeane)

GeringereLösung

CO2 Bindung

Treibhausgase

Erwärmung

Verdunstung &Trockenstress

Weniger Wachstum(Mehr Veratmung)

Mehr CO2 Atm

Erwärmung Erwärmung Erwärmung Erwärmung

Dies ist eine ÜberschriftDies ist eine Überschrift

LETTERS

Ensemble reconstruction constraints on the globalcarbon cycle sensitivity to climateDavid C. Frank1,2, Jan Esper3, Christoph C. Raible2,4, Ulf Buntgen1, Valerie Trouet1, Benjamin Stocker2,4

& Fortunat Joos2,4

The processes controlling the carbon flux and carbon storage of theatmosphere, ocean and terrestrial biosphere are temperaturesensitive1–4 and are likely to provide a positive feedback leading toamplified anthropogenic warming3. Owing to this feedback, at time-scales ranging from interannual to the 20–100-kyr cycles of Earth’sorbital variations1,5–7, warming of the climate system causes a netrelease of CO2 into the atmosphere; this in turn amplifies warming.But the magnitude of the climate sensitivity of the global carbon cycle(termed c), and thus of its positive feedback strength, is under debate,giving rise to large uncertainties in global warming projections8,9.Here we quantify the median c as 7.7 p.p.m.v. CO2 per 6C warming,with a likely range of 1.7–21.4 p.p.m.v. CO2 per 6C. Sensitivity experi-ments exclude significant influence of pre-industrial land-use changeon these estimates. Our results, based on the coupling of a probabi-listic approach with an ensemble of proxy-based temperature re-constructions and pre-industrial CO2 data from three ice cores, pro-vide robust constraints for c on the policy-relevant multi-decadal tocentennial timescales. By using an ensemble of .200,000 members,quantification of c is not only improved, but also likelihoods can beassigned, thereby providing a benchmark for future model simula-tions. Although uncertainties do not at present allow exclusion of ccalculated from any of ten coupled carbon–climate models, we findthat c is about twice as likely to fall in the lowermost than in theuppermost quartile of their range. Our results are incompatibly lower(P , 0.05) than recent pre-industrial empirical estimates of

40 p.p.m.v. CO2 per 6C (refs 6, 7), and correspondingly suggest80% less potential amplification of ongoing global warming.Approximately 40% of the uncertainty related to projected warm-

ing of the twenty-first century stems from the unknown behaviour ofthe carbon cycle10, which is an important component of the globalclimate system3,11. Constraining slow oceanic processes, possible CO2

fertilization of plants, and c—which is proportional to the globalCO2/temperature feedback—is of key importance to reduce theseuncertainties11. Coupled carbon–climate models show a wide rangein feedback strength, with 20–200 p.p.m.v. of temperature-drivenCO2 by 2100 (ref. 8). The substantial anthropogenic perturbationof the carbon cycle and physical climate system characteristics limitspossibilities of providing tight constraints during the recent (instru-mental) period, while past glacial–interglacial CO2 fluctuations aregoverned by currently poorly quantified processes11. This means thatneither the interannual nor glacial–interglacial domains permit feed-back quantification on timescales relevant for addressing amplifica-tion of anthropogenic global warming.

Highly resolved reconstructions of temperature and atmosphericCO2 available for the past millennium (Fig. 1) provide significantpotential for observational constraints12,13: the climate state is broadly

stationary with respect to glacial–interglacial processes, and the multi-decadal to centennial-scale periods within policymakers’ horizons aremet. Reconstructed long-term decreases in CO2 concentration areindicative of positive feedbacks in the cooling transition from theMedieval Warm Period (MWP) into the Little Ice Age (LIA). Theaverage correlation between individual temperature reconstructionsand the mean CO2 record is 0.47 over the pre-industrial 1050–1800period (all years are AD), increasing to 0.57 with a 50-year CO2 res-ponse lag—such timing is consistent with modelled CO2 response to atemperature step change12. Relying upon temperature and CO2

covariation, estimates for c have been derived by regressing individualtemperature reconstructions to a given CO2 record1,6,7. Yet, greatscatter in c, from a few to more than 40 p.p.m.v. per uC, closely reflectsthe choice of the individual temperature and/or CO2 estimates usedfor analysis6,7.

Particularly relevant to constraining sensitivities of the Earth’scoupled climate system is the amplitude of hemispheric to global-scale

1Swiss Federal Research Institute WSL, Zurcherstrasse 111, CH-8903 Birmensdorf, Switzerland. 2Oeschger Centre for Climate Change Research, University of Bern, Zahringerstrasse25, CH-3012 Bern, Switzerland. 3Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany. 4Climate and Environmental Physics, PhysicsInstitute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.

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–0.6

–0.4

–0.2

0.0

0.2

CO

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.p.m

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Year AD

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Figure 1 | Temperature and CO2 variability over the past millennium.a, Large-scale reconstructions as originally calibrated (see Methods fordetails); records published before 2007 shown as in ref. 11. b, Variations inCO2 concentration from three ice core records shown to 285 p.p.m.v.Measurements for Law Dome (LD) and Dronning Maud Land (DML) weresufficient to yield smoothed estimates for CO2 evolution. Note broad long-term decline in CO2 concentrations in the South Pole (SP) record. Records ina and b were smoothed with 80- and 50-year splines, respectively. Thesefilters yield similar spectra owing to the lack of annual values and thesmoothing effects of gaseous diffusion in b (see Supplementary Fig. 4).

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Weiterführend >>

Kalkulation CO2-temperatursensitivität

Frank et al. 201032

Weiterführend >>

CO

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cent

ratio

n (p

pm)

Carbon dioxide concentration at Mauna Loa ObservatoryAugust 29, 2019Latest CO2 reading

Full Record ending August 31, 2019

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015310

320

330

340

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CO2 von schneereichen Eisbohrkernen

Weiterführend >>Temperaturen von Baumjahrringen

Frank et al. 2010

Average correlation is 0.47, increasing to 0.57 with a 50-year CO2 response lag.

Zusammenhang zw. Temperatur und CO2

Frank et al. 2010

Weiterführend >>

Klimatische Sensitivität von CO2

Frank et al. 2010

Weiterführend >>

[CO2]Atm vs. T1550–1800

[CO2]Atm vs. T1050–1549

7.7 ppmv/°C

[CO2]Atm

1000 1800

TemperaturePro °C Erwärmung –> +7.7 ppmv CO2 (1.7–21.4 ppmv!).

Unvereinbar (p<0.05) kleiner als letzte Befunde (40 ppmv/°C). .

Das entspricht ca. 80% weniger zusätzliche Erwärmung als bisher angenommen.

Dies ist eine ÜberschriftDies ist eine Überschrift

LETTERS

Ensemble reconstruction constraints on the globalcarbon cycle sensitivity to climateDavid C. Frank1,2, Jan Esper3, Christoph C. Raible2,4, Ulf Buntgen1, Valerie Trouet1, Benjamin Stocker2,4

& Fortunat Joos2,4

The processes controlling the carbon flux and carbon storage of theatmosphere, ocean and terrestrial biosphere are temperaturesensitive1–4 and are likely to provide a positive feedback leading toamplified anthropogenic warming3. Owing to this feedback, at time-scales ranging from interannual to the 20–100-kyr cycles of Earth’sorbital variations1,5–7, warming of the climate system causes a netrelease of CO2 into the atmosphere; this in turn amplifies warming.But the magnitude of the climate sensitivity of the global carbon cycle(termed c), and thus of its positive feedback strength, is under debate,giving rise to large uncertainties in global warming projections8,9.Here we quantify the median c as 7.7 p.p.m.v. CO2 per 6C warming,with a likely range of 1.7–21.4 p.p.m.v. CO2 per 6C. Sensitivity experi-ments exclude significant influence of pre-industrial land-use changeon these estimates. Our results, based on the coupling of a probabi-listic approach with an ensemble of proxy-based temperature re-constructions and pre-industrial CO2 data from three ice cores, pro-vide robust constraints for c on the policy-relevant multi-decadal tocentennial timescales. By using an ensemble of .200,000 members,quantification of c is not only improved, but also likelihoods can beassigned, thereby providing a benchmark for future model simula-tions. Although uncertainties do not at present allow exclusion of ccalculated from any of ten coupled carbon–climate models, we findthat c is about twice as likely to fall in the lowermost than in theuppermost quartile of their range. Our results are incompatibly lower(P , 0.05) than recent pre-industrial empirical estimates of

40 p.p.m.v. CO2 per 6C (refs 6, 7), and correspondingly suggest80% less potential amplification of ongoing global warming.Approximately 40% of the uncertainty related to projected warm-

ing of the twenty-first century stems from the unknown behaviour ofthe carbon cycle10, which is an important component of the globalclimate system3,11. Constraining slow oceanic processes, possible CO2

fertilization of plants, and c—which is proportional to the globalCO2/temperature feedback—is of key importance to reduce theseuncertainties11. Coupled carbon–climate models show a wide rangein feedback strength, with 20–200 p.p.m.v. of temperature-drivenCO2 by 2100 (ref. 8). The substantial anthropogenic perturbationof the carbon cycle and physical climate system characteristics limitspossibilities of providing tight constraints during the recent (instru-mental) period, while past glacial–interglacial CO2 fluctuations aregoverned by currently poorly quantified processes11. This means thatneither the interannual nor glacial–interglacial domains permit feed-back quantification on timescales relevant for addressing amplifica-tion of anthropogenic global warming.

Highly resolved reconstructions of temperature and atmosphericCO2 available for the past millennium (Fig. 1) provide significantpotential for observational constraints12,13: the climate state is broadly

stationary with respect to glacial–interglacial processes, and the multi-decadal to centennial-scale periods within policymakers’ horizons aremet. Reconstructed long-term decreases in CO2 concentration areindicative of positive feedbacks in the cooling transition from theMedieval Warm Period (MWP) into the Little Ice Age (LIA). Theaverage correlation between individual temperature reconstructionsand the mean CO2 record is 0.47 over the pre-industrial 1050–1800period (all years are AD), increasing to 0.57 with a 50-year CO2 res-ponse lag—such timing is consistent with modelled CO2 response to atemperature step change12. Relying upon temperature and CO2

covariation, estimates for c have been derived by regressing individualtemperature reconstructions to a given CO2 record1,6,7. Yet, greatscatter in c, from a few to more than 40 p.p.m.v. per uC, closely reflectsthe choice of the individual temperature and/or CO2 estimates usedfor analysis6,7.

Particularly relevant to constraining sensitivities of the Earth’scoupled climate system is the amplitude of hemispheric to global-scale

1Swiss Federal Research Institute WSL, Zurcherstrasse 111, CH-8903 Birmensdorf, Switzerland. 2Oeschger Centre for Climate Change Research, University of Bern, Zahringerstrasse25, CH-3012 Bern, Switzerland. 3Department of Geography, Johannes Gutenberg University, Becherweg 21, 55099 Mainz, Germany. 4Climate and Environmental Physics, PhysicsInstitute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.

Tem

pera

ture

ano

mal

y(º

C w

.r.t.

1961

–90)

1000 1200 1400 1600 1800 2000

–1.0

–0.8

–0.6

–0.4

–0.2

0.0

0.2

CO

2 (p

.p.m

.v.)

1000 1200 1400 1600 1800 2000270

275

280

285LDDMLSPAll

Year AD

a

b

Figure 1 | Temperature and CO2 variability over the past millennium.a, Large-scale reconstructions as originally calibrated (see Methods fordetails); records published before 2007 shown as in ref. 11. b, Variations inCO2 concentration from three ice core records shown to 285 p.p.m.v.Measurements for Law Dome (LD) and Dronning Maud Land (DML) weresufficient to yield smoothed estimates for CO2 evolution. Note broad long-term decline in CO2 concentrations in the South Pole (SP) record. Records ina and b were smoothed with 80- and 50-year splines, respectively. Thesefilters yield similar spectra owing to the lack of annual values and thesmoothing effects of gaseous diffusion in b (see Supplementary Fig. 4).

Vol 463 | 28 January 2010 | doi:10.1038/nature08769

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Weiterführend >>

Favourite Quote“Frank et al. therefore save about 50 trillion U.S. dollars needed for the cooling by 1 °C.”

www.blogs.uni-mainz.de/fb09climatology/publications-jan-esper/

37

Take home messagesVielen Dank!