 FHI TECHNICAL REPORT 

Global Catastrophic Risks Survey
Anders Sandberg
Nick Bostrom
Technical Report #2008-1

Cite as:Sandberg, A. & Bostrom, N. (2008): “Global Catastrophic Risks Survey”, TechnicalReport #2008-1, Future of Humanity Institute, Oxford University: pp. 1-5.

The views expressed herein are those of the author(s) and do not necessarily reflect theviews of the Future of Humanity Institute.

G LOBAL C ATASTROPHIC R ISKS S URVEY(2008)
Technical Report 2008/1
Published by Future of Humanity Institute, Oxford University
Anders Sandberg and Nick Bostrom
At the Global Catastrophic Risk Conference in Oxford (17‐20 July, 2008) an informal
survey was circulated among participants, asking them to make their best guess at thechance that there will be disasters of different types before 2100. This report summarizes
the main results.
The median extinction risk estimates were:Risk

At least 1 million
dead
25%

At least 1 billion
dead
10%

Human extinction

10%

5%

5%

98%

30%

4%

30%

10%

2%

Total killed in all
nuclear wars.

30%

10%

1%

Number killed in
the single biggest
nanotech accident.
Number killed in
the single biggestnatural pandemic.
Total killed in allacts of nuclear
terrorism.
Overall risk ofextinction prior to2100

5%

1%

0.5%

60%

5%

0.05%

15%

1%

0.03%

n/a

n/a

19%

Number killed bymolecular nanotech
weapons.
Total killed bysuperintelligent AI.
Total killed in allwars (includingcivil wars).
Number killed in
the single biggest
engineered
pandemic.

5%

These results should be taken with a grain of salt. Non‐responses have been omitted,
although some might represent a statement of zero probability rather than no opinion.

1There are likely to be many cognitive biases that affect the result, such as unpacking bias
and the availability heuristic‒‐well as old‐fashioned optimism and pessimism.
In appendix A the results are plotted with individual response distributions visible.

Other Risks
The list of risks was not intended to be inclusive of all the biggest risks. Respondents
were invited to contribute their own global catastrophic risks, showing risks they
considered significant. Several suggested totalitarian world government, climate‐induced
disasters, ecological/resource crunches and “other risks”‒‐specified or unknowable
threats. Other suggestions were asteroid/comet impacts, bad crisis management, high‐tech asymmetric war attacking brittle IT‐based societies, back‐contamination from spaceprobes, electromagnetic pulses, genocide/democides, risks from physics research anddegradation of quality assurance.

Suggestions
Respondents were also asked to suggest what they would recommend to policymakers.
Several argued for nuclear disarmament, or at least lowering the number of weapons
under the threshold for existential catastrophe, as well as reducing stocks of highly
enriched uranium and making nuclear arsenals harder to accidentally launch.
One option discussed was formation of global biotech‐related governance, legislationand enforcement, or even a global body like the IPCC or UNFCCC to study and act on
catastrophic risk. At the very least there was much interest in developing defenses
against misuses of biotechnology, and a recognition for the need of unbiased early
detection systems for a variety of risks, be they near Earth objects or actors with WMD
capabilities.
Views on emerging technologies such as nanotech, AI, and cognition enhancement weremixed: some proposed avoiding funding them; others deliberate crash programs toensure they would be in the right hands, the risks understood, and the technologies able
to be used against other catastrophic risks.
Other suggestions included raising awareness of the problem, more research on cybersecurity issues, the need to build societal resiliency in depth, prepare for categories ofdisasters rather than individual types, building refuges and change energy consumption
patterns.

Appendix A
Below are the individual results, shown as grey dots (jittered for distinguishability) andwith the median as a bar.

2

Total killed in
all acts ofnuclear
terrorism.
>1 million
dead: median15%>1 billion dead:median 1%
Extinction:
median 0.03%

Total killed in
all nuclearwars.
>1 million
dead: median30%>1 billion dead:median 10%
Extinction:
median 1%

Number killedin the single
biggest natural
pandemic.
>1 million
dead: median60%>1 billion dead:median 5%
Extinction:
median 0.05%

3Number killedin the single
biggestengineered
pandemic.
>1 million
dead: median30%>1 billion dead:median 10%
Extinction:
median 2%

Total killed bysuperintelligentAI.
>1 million
dead: median10%>1 billion dead:median 5%
Extinction:
median 5%

Number killedin the single
biggestnanotechaccident.
>1 million
dead: median5%>1 billion dead:median 1%
Extinction:
median 0.5%

4

Number killed
by molecular
nanotechweapons.
>1 million
dead: median25%>1 billion dead:median 10%
Extinction:
median 5%

Total killed in
all wars(including civilwars).
>1 million
dead: median98%>1 billion dead:median 30%
Extinction:
median 4%

Total risk ofextinction:
median 19%5