The Age of Computers - University of Torontosme/PMU199-climate-computing/Week7-seminar… · 1 The Age of Computers 1950s: John Von Neuman designs the first (?) electronic computer,

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The Age of Computers

1950s: John Von Neuman designs the first (?) electronic computer, ENIAC, applies it to weather forecasting

Imagines uses in weather control, geo-engineering, etc.

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The ENIAC Forecasts (1)

Image: http://maths.ucd.ie/~plynch/Publications/ENIAC-BAMS-08.pdf

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The ENIAC forecasts (2)

Image: http://maths.ucd.ie/~plynch/Publications/ENIAC-BAMS-08.pdf

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PHONIAC

Image: http://mathsci.ucd.ie/~plynch/Publications/PHONIAC.html

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Moore’s Law

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Supercomputers

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Where are these supercomputers?

http://infosthetics.com/archives/2010/05/bbc_news_visualizing_the_top_500_supercomputer_report.html

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Reminder: How the models work

http://www.iac.ethz.ch/groups/knutti/research

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More resolution…

http://onlinelibrary.wiley.com/doi/10.1111/j.1740-9713.2010.00403.x/abstract

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IPCC Model evolution

http://eo.ucar.edu/staff/rrussell/climate/modeling/climate_model_resolution.html

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Can Moore’s Law continue forever?

http://wccftech.com/moores-law-will-be-dead-2020-claim-experts-fab-process-cpug-pus-7-nm-5-nm/

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Paper Folding

After 4 folds, 1 cm thickHow thick after 33 folds?

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6000

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33

Thickness (km)

0.000001

0.00001

0.0001

0.001

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0.1

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1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33

Thickness (km)

1cm 1mm

10cm 1m

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1km 10km

100km 1000km

10,000km

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Understanding Exponential Growth

2014

0

5

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1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015

peta

FLO

PS

Peak Speed of fastest supercomputer

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Understanding Exponential Growth

2014

0

10

20

30

40

50

60

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015

peta

FLO

PS

Peak Speed of fastest supercomputer

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Understanding Exponential Growth

20140

50

100

150

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250

300

350

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020

peta

FLO

PS

Peak Speed of fastest supercomputer

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Why does this graph have this shape?

http://novel-infectious-diseases.blogspot.ca/2014/10/comparing-who-and-cdc-projections-of.html

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And this one?

Lang et al (2014). The influence of societal individualism on a century of tobacco use: modelling the prevalence of smoking, 1–20. Dynamical Systems; Physics and Society.

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Population Growth and Projections

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Multi-loop systems

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Welcome to the Anthropocene…

Sou

rce:

Ste

ffen,

Grin

eval

d, C

rutz

en &

McN

eill

“T

he A

nthr

opoc

ene:

con

cept

ual a

nd h

isto

rical

per

spec

tives

. 201

1.

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Welcome to the Anthropocene…

Sou

rce:

Ste

ffen,

Grin

eval

d, C

rutz

en &

McN

eill

“T

he A

nthr

opoc

ene:

con

cept

ual a

nd h

isto

rical

per

spec

tives

. 201

1.

22

About that Ebola Projection…

http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/cumulative-cases-graphs.html

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Dynamic Behaviour Over Time

World Population, 1800-2100

today

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1) Some curves that look exponential are not!

2) Exponential growth cannot continue

forever

3) Predicting the peak of a growth curve is really hard

(be suspicious of any precise predictions)

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Key ideas

Finite planet has a “carrying capacity”Growth of Population x ecological footprint will exceed it This happened sometime in the 1980sReduction is inevitable; can be managed or can be collapse

There are limits on stocks...E.g. resources such as oil, coal, scarce mineralsE.g. pollution sinks, such as CO2 in the atmosphere(In the past, we’ve been good at finding substitutions…)

…but the important limits are on flowsE.g. Rate at which we can grow food, recycle waste, etc.E.g. Rate at which we can transition to alternative technologiesHence, population can overshoot carrying capacity

People often deny a limit has been reached until after a collapse

E.g. Dotcom “bubble”; banking crisis of 2007;E.g. Economic inequality? Climate change?

26 Steffen, W., et. al. (2015). Planetary boundaries: Guiding human development on a changing planet. Science, 347(6223).

Planetary Boundaries