tobias gerken geoengineering

Tobias Gerken The Pennsylvania State University

tug15@psu.edu

Geoengineering

CLIMATE CHANGE (IN A NUTSHELL)

Global Energy Budget

Greenhouse Effect

After: Kiehl & Trenberth, 1997

The Carbon Cycle

Sarmiento & Gruber, 2002

Global Temperatures (I)

NASA Goddard Institute for Space Studies

Mann et al., 1999 “The Hockey Stick”

Global Temperatures (II)

Columbia University

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

Whose fault is it?

CO2 Emissions by Country (2011)

Netherlands Environmental Assessment Agency

Whose fault is it?

Total GHG Emissions by Country (2011)

Netherlands Environmental Assessment Agency

Whose fault is it?

CO2 Emissions per person (2011)

Netherlands Environmental Assessment Agency

Whose fault is it?

Historical Emissions (1850-2007)

Netherlands Environmental Assessment Agency

Whose fault is it?

Historical Emissions per person (1850-2007)

Netherlands Environmental Assessment Agency

Dealing with climate change

• Do Nothing

• Adapt

• Mitigate (Prevent)

• (Geo- engineering)

Xkcd.com

GEOENGINEERING

We are a force of ‘nature’ (?!)

Paul Crutzen: “The Anthropocene”

Rockström, et al. (2009): Planetary Boundaries […] Ecology and Society 14: p 33-

Geoengineering methods

Solar Radiation Management

After: Kiehl & Trenberth, 1997

CO2 removal

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

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

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

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

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

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

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

A first evaluation

The Royal Society, 2009

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.