HUMAN EXTINCTION SCENARIOS

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HUMAN EXTINCTION SCENARIOS

• Bruce Tonn, University of Tennessee
• Donald MacGregor, Decision Research

WSFS Conference Budapest, Hungary August, 2005
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OUTLINE

• What is a human extinction scenario?
• Types of human extinction scenarios
• Reasons to develop
• Why estimate the probability of human extinction?
• Estimating the probabilities
• Example Scenario
• Special issue of Futures on human extinction
  scenarios

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WHAT IS A HUMAN EXTINCTION SCENARIO?

• A series of events that would lead to the
  extinction of the human race
• Plausible, not necessarily probable
• Stand Alone
• Incorporates human response and adaptation
• Likely to be fairly lengthy

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TYPES OF HUMAN EXTINCTION SCENARIOS

• Failed best effort Right decisions turn out
  in hindsight to have been wrong
• Unavoidable All paths lead to extinction
• Human folly The bad side of human nature
  ignores threats to survival
• Too little, too late Concern arises too late,
  decisions are made in haste and are wrong

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REASONS TO DEVELOP HUMAN EXTINCTION SCENARIOS

• Part of global foresight activities
• Identify key risks and combinations of risks
• First step towards estimating the current
  probability of human extinction

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WHY ESTIMATE THE PROBABILITY OF HUMAN EXINCTION?

• To make the risk real to policy makers
• In the U.S., politicians tend to react when risk
  of death to an individual from an involuntary
  risk exceeds 1 in a million during a lifetime
• To spur discussion about an acceptable level of
  risk of human extinction
• 1 in ten billion?
• To inform world community if the situation is
  serious or not
• More rigorous follow-up to Rees subjective
  judgment of a 50 chance of human extinction over
  the next 100 years

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ESTIMATING EXTINCTION PROBABILITIES

• Very difficult little or no data
• Complex system
• Huge uncertainties
• Billions of paths into the future
• Human response complicates the task

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ESTIMATING EXTINCTION PROBABILITIES

• Assume each path into the future is equally
  probable
• Assume that one scenario represents one path
• Distill key variables from a set of scenarios
• Determine ranges of values for each variable
• Estimate number of possible worlds at various
  times into the future
• Calculate lower probability of extinction
• Increase sophistication of approach over time

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BRIEF EXAMPLE OF A HUMAN EXTINCTION SCENARIO
8 B
HIV/AIDS
Flu Pandemic
Global Climate Change -- Drought
7 B
6 B
Collapse Energy Sector
Regional Wars
Medical Advances
5 B
Collapse Global Agriculture
Human
4 B
Exhaustion of Global Aquatic, Wood and Wildlife
Resources
Population
Fragile Peace
3 B
Pestilence Further Cripples Global Agriculture
Collapse of Human Fertility
2 B
Runaway Global Warming
Massive Species Extinction
1 B
Most Food Disappears
Hell on Earth
0
2100
2200
2300
2400
2500
2600
2700
2800
2900
3000
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SPECIAL ISSUE OF FUTURES ON HUMAN EXTINCTION
SCENARIOS

• Special issue editors Bruce Tonn and Donald
  MacGregor
• Each paper presents in-depth and convincing
  scenario 0 to 10,000 years
• All papers will be vetted by panel
• No alien attacks allowed!
• All other risks allowed (want some scenarios that
  do not rely on nuclear war or collisions with
  asteroids)
• Due March 15, 2006 Send to btonn_at_utk.edu