This document discusses climate change and various approaches to geoengineering. It provides an overview of climate science concepts like the greenhouse effect and global temperatures. It then discusses different geoengineering methods like solar radiation management and CO2 removal. Key issues that need consideration with geoengineering are discussed, such as economics, geopolitics, ethics, risks, and science. Overall, the document analyzes various factors to consider with geoengineering and recommends further research and international cooperation to better understand associated challenges.

1. Tobias Gerken The Pennsylvania State University tug15@psu.edu
Geoengineering

2. CLIMATE CHANGE (IN A NUTSHELL)

3. Global Energy Budget
Greenhouse Effect
After: Kiehl & Trenberth, 1997

4. The Carbon Cycle
Sarmiento & Gruber, 2002

5. Global Temperatures (I)
NASA Goddard Institute for Space Studies
Mann et al., 1999 “The Hockey Stick”

6. Global Temperatures (II)
Columbia University

7. Anthropogenic Climate Change
•Global temperatures are rising.
•The dominating mechanism is enhanced green house effect.
•What are the consequences?
•What should we do about it?
Fact
Fact
Research
Debate

8. Whose fault is it?
CO2 Emissions by Country (2011)
Netherlands Environmental Assessment Agency

9. Whose fault is it?
Total GHG Emissions by Country (2011)
Netherlands Environmental Assessment Agency

10. Whose fault is it?
CO2 Emissions per person (2011)
Netherlands Environmental Assessment Agency

11. Whose fault is it?
Historical Emissions (1850-2007)
Netherlands Environmental Assessment Agency

12. Whose fault is it?
Historical Emissions per person (1850-2007)
Netherlands Environmental Assessment Agency

13. Dealing with climate change
•Do Nothing
•Adapt
•Mitigate (Prevent)
•(Geo- engineering)
Xkcd.com

14. GEOENGINEERING

15. We are a force of ‘nature’ (?!)
Paul Crutzen: “The Anthropocene”
Rockström, et al. (2009):
Planetary Boundaries […]
Ecology and Society 14: p 33-

16. Geoengineering methods
Solar Radiation Management
After: Kiehl & Trenberth, 1997
CO2 removal

17. Geoengineering methods
•Your turn (In groups):
1.How does the method work?
2.What are the advantages?
3.What are the disadvantages/ dangers?
4.How will it affect society?
5.Would you recommend it?
Write down the answers to turn in.
You will present your answers (one minute presentation)
Higgins, 2014

18. Key issues to think about
•Economics: How much will it cost?
•Geopolitics: How do we regulate it?
•Ecosystems: How will nature react?
•Ethics: Should we do it?
•Risks: What can go wrong?
•Science: What do we know?
Carbon Capture and Storage www.fastcompany.com

19. Economics
•The “Stern Report” (2007): Climate change mitigation will cost $ 1 trillion per year (1-2% of world GDP)
 $ 100 per ton of carbon
•We have little knowledge what geoengineering will cost
Cloud brightening. Credit: McNeill

20. Geopolitics
•Geoengineering by definition is global!
•There will/ might be winners and losers?
•Who will pay?
•Who decides what to do?
•Do we need a global climate “police”?
Precipitation change due to sulphate aerosol geoengineering, Rasch et al 2008

21. Ethics/ Environment
•How much do we need to know before we can do geoengineering?
•Is it morally wrong?
•Are some options better than others?
•Ecosystems will be disrupted.
•Do we care?
An algal bloom,
wikimedia commons

22. Risks
•What happens if technologies fail?  Uncertainty
•Unintended consequences …
•Get out of jail free card/ magic bullet?
•We cannot do this forever  bridge technology
•Geopolitical consequences: Less precipitation in China, USA, Russia …
Credit: loadtr.com

23. How should we make decisions?
The Royal Society Report:
1.Legality
2.Effectiveness
3.Timeliness
4.Environmental, social and economic impacts
5.Costs
6.Funding
7.Public Acceptability  this is a biggie
8.Reversibility

24. A first evaluation
The Royal Society, 2009

25. Science
•Royal Society Report, 2009
•The American Meteorological Society recommends:
1.Enhanced research on the scientific and technological potential for geoengineering the climate system, including research on intended and unintended environmental responses.
2.Coordinated study of historical, ethical, legal, and social implications of geoengineering that integrates international, interdisciplinary, and intergenerational issues and perspectives and includes lessons from past efforts to modify weather and climate.
3.Development and analysis of policy options to promote transparency and international cooperation in exploring geoengineering options along with restrictions on reckless efforts to manipulate the climate system.