Lecture: Tuesday, 10-12; Prof. Dr. Gerrit Lohmann; Dr. Martin Werner

Description

This lecture will give an overview about the climate system and its changes during the past, focussing on the last few million years. We begin by describing the external astronomical forcing of the climate system and the observed response, as represented by proxy evidence for paleoclimatic variations. The main components and processes of the climate system, as well as available different dating and analyses methods for paleoclimate research will be explained. Key paleoclimate archives, e.g. ice cores, marine sediment cores and different terrestrial records, will be discussed. The general overview will be supplemented by a presentation of some of the latest research results and most important open questions within the related fields of paleoclimate research. We will show that the past climate dynamics broadens our view of the climate system in general, including the positive and negative feedbacks determining climate sensitivity. Such an approach is necessary to put our recent and expected future climate change into a long-term perspective.



German Version:

Diese Vorlesung gibt einen Überblick über das Klimasystem und seiner Veränderungen in der Vergangenheit. Wir beginnen mit der Beschreibung des äußeren astronomischen Antriebs des Klimasystems und der beobachteten Reaktion, die in Umweltarchiven beobachtet wurden. Die Hauptkomponenten und -prozesse des Klimasystems sowie verschiedene Datierungs- und Analysemethoden für die Paläoklimaforschung werden erläutert. Wichtige Klimaarchive, z.B. Eisbohrkerne, marine Sedimentbohrkerne und verschiedene terrestrische Aufzeichnungen werden diskutiert. Es wird gezeigt, dass die langfristige Klimadynamik unsere Sicht auf das Klimasystem im Allgemeinen erweitert, einschließlich der positiven und negativen Rückkopplungen, die für die Stabilität des Klimas wichtig sind. Wir stellen weiterhin da, wie sich die letzten Dekaden und die erwarteten künftigen Klimawechsel in eine langfristige Perspektive einordnen.



Content

feedback mechanisms in the climate system; the role of the global atmosphere and ocean circulation for long-term climate change; Holocene climate; Climate modes like ENSO and NAO; deglaciation; Glacial climate; Milankovitch theory of the ice ages; Cenozoic climate changes; Biogeochemical cycles; Proxy data; Isotopes

Learning outcome

Advanced knowledge of the climate system, applications in the fields of climate. Programming skills and usage of the climate data operators. Practicals complement the lessons.

Formalities

Code no. 01-01-03-CliS2-V

StudIP

Assignment to study programmes: Optional compulsory for MSc Environmental Physics, for MSc Physik (Umweltphysik), MSc Space Sciences and Technologies (Physics for Space Observations)

link to zoom meeting

Workload /credit points: 3 CP, 90 h

• lecture: 28 h (2h x 14 weeks)

• repeating the lectures/learning/reading: 28 h (2h x 14 weeks)

• example homework: 24 h (6 x 4h)

• additional preparation for exam: 10 h

Course and examination performance

Course achievements:

We require active participation with at least one time showing a solution in the chat room. Working in study groups is encouraged, but each student is responsible for his/her own solution. The solution is typewritten (e.g. with LaTex, Rmarkdown, or word), we allow up to 3 persons to be listed on a solution sheet.

Examination achievements:

You have to pass the written or oral exam at xxx Room: see anouncement (probably online, 25 min)

The exam is based on the the general content of the lecture and exercises. The procedure follows the rules of pep.

Time table

1) Nov 3 Challenges of climate change (GL)

Content: Intro and warming up, climate change, consequences

 

2) Nov 10 Global water cycle (MW)

Content: Water in the Earth system components, Oxygen Isotopes and ice cores, signature in ice cores, drilling ice cores

 

3) Nov 17 Ice Ages and Astronomical theory (GL)

Content: Basics in astronomy (Keppler’s laws), Orbital parameters, Dynamics of ice ages, Termination, Mid-Pleistocene transition

Overview articles by A. Berger, Labeyrie et al., Wally, GL, wikipedia

Here is Exercise 1 “Tropic of Cancer” to be submitted to GL until Nov 24. Please build groups of 2-3 and send the solutions electronically as pdf, word or LaTex. No handwriting.

 

4) Nov 24 Astronomical theory and millennial variability (GL)

Content: Earth orbital variations, Glacial-interglacial changes, millennial variability (abrupt climate changes like Heinrich events), Spectrum

Exercise 2 “Earth orbital variations” Rmd file: Orbital_2020.Rmd, data file: ins_data.txt

Submission of Exercise 1 to GL

 

5) Dec 1 The Last Glacial Maximum (MW)

Content: Climate of the LGM, circulation, reconstructions of atmospheric gas composition

Exercise 3 “Glacial climate” “Glacial climate”

netcdf file: PI.nc, netcdf file: LGM.nc

Submission of Exercise “Earth orbital variations” to GL

 

6) Dec 8 Biogeochemistrical cycles (MW)

Content: chemical substances, biosphere, turnover times, circulation of chemical nutrients (carbon, oxygen, nitrogen, phosphorus)

Submission of Exercise 3 “Glacial climate” to MW

 

7) Dec 15 Vegetation and dust (MW)

Content: Aridity and dust,
vegetation dynamics, Daisy world, land use, terrestrial biosphere

Discussion of Exercise 3 “Glacial climate” by students

 

8) Dec 22 Climate Models (MW)

Content: Structure of climate models, components, climate scenarios: from past to the future

Exercise 4 “Climate models”

 

no lecture on Dec 29 and Jan 5

 

9) Jan 12 Climate data analysis (GL)

Content: Different kind of data: historical, reanalysis, paleoclimate data; Model data; Energy balance model

Exercise 5 “Analysing model data”

Discussion of Exercises 1 “Tropic of Cancer” and 2 “Earth orbital variations” by students

Submission of Exercise “Climate models” to MW

 

10) Jan 19 Climate variability (GL)

Content: NAO, ENSO, extremes, detection, Holocene, statistical climate reconstructions in the Holocene

Exercise 6 “Analysing atmospheric teleconnections”

Submission of Exercise 5 “Analysing model data” to GL

 

11) Jan 26 The last 100 million years (GL)

Content: Cenozoic climate change, Climate warming backwards, Cretaceous warm planet, Eocene-Oligocene and Miocene transitions

Ocean gateways as potential driver, Climate sensitivity, Greenhouse gases, Energy balance and transport in the atmosphere-ocean system

Discussion of Exercise 5 “Analysing model data” by students

Submission of Exercise 6 “Analysing atmospheric teleconnections” to GL

 

12) Feb 2 The current debate (GL)

Climate Change: The scientific debate and uncertainties of climate change projections, scientific controvercies, political and non-scientific debate, carbon footprint

Discussion of Exercise 6 “Analysing atmospheric teleconnections” by students

 

13) Feb 9 Regional and global changes (MW)

Content: Regional and global signals: Monsoons, Permafrost; Archives of climate change

Discussion of Exercise 4 “Climate models”

 

14) Feb 16 Summary and outlook (MW)

Content: Summary of models, available data, link of past-present-future, knowledge transfer

Themes for potential Master Theses

Questions about the course and exam via chat

 

15) Exam at xxx, online

 


 

Literature:

Bradley, R., Paleoclimatology-Reconstructing climates of the Quaternary,

Saltzman, B., Dynamical Paleoclimatology - A generalized theory of global climate change, Academic Press, San Diego, 2002, 354 pp.

Ruddiman, W.F. Earth’s Climate Past and Future

Paleoclimate, Global Change and the Future, 2003 Keith D. Alverson, Raymond S. Bradley, Thomas F. Pedersen(Editors)

Broecker, W. S.,THE GLACIAL WORLD ACCORDING TO WALLY

Ensure access to affordable, reliable, sustainable and modern energy

One-dimensional EBM (link) This notebook is part of The Climate Laboratory by Brian E. J. Rose, University at Albany.

The Warming Papers: The Scientific Foundation for the Climate Change Forecast David Archer and Raymond Pierrehumbert (Eds.). Book about Global warming papers: Global warming is arguably the defining scientific issue of modern times, but it is not widely appreciated that the foundations of our understanding were laid almost two centuries ago with the postulation of a greenhouse effect by Fourier in 1827. The sensitivity of climate to changes in atmospheric CO2 was first estimated about one century ago, and the rise in atmospheric CO2 concentration was discovered half a century ago. The fundamentals of the science underlying the forecast for human-induced climate change were being published and debated long before the issue rose to public prominence in the last few decades.

The Warming Papers is a compendium of the classic scientific papers that constitute the foundation of the global warming forecast. The paper trail ranges from Fourier and Arrhenius in the 19th Century to Manabe and Hansen in modern times. Archer and Pierrehumbert provide introductions and commentary which places the papers in their context and provide students with tools to develop and extend their understanding of the subject.

The book captures the excitement and the uncertainty that always exist at the cutting edge of research, and is invaluable reading for students of climate science, scientists, historians of science, and others interested in climate change.

    


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Hintergrundinformation aus IPCC Berichten:
Deutsche Zusammenfassung,

Kernaussagen

Deutsche Zusammenfassung 2007;

Deutsche Version 2007

AR5 IPCC Report

Technical Summary