One damn thing after another cascading global change

Dr Bob ScholesCSIR Fellow

UNISA

College of Economic and Management Science

25 November 2009

© CSIR 2009 www.csir.co.za

• Global financial crisis • Peak oil, fuel price hikes, energy crisis

in South Africa• Food price escalation, real hunger

affecting nearly a fifth of the world’s population

• Water shortages in many parts of the world

• The sixth extinction crisis….

Have you noticed that everything seems to be going wrong at once?

What is going on???

1. A globally-connected world

Climate change•Temperature•Rainfall•Sea level rise•winds•Means and extremes

Biogeochemical change•Atmospheric CO2

•Greenhouse gases•N deposition•Sediment transport•P loading

Land cover change•Cropland expansion•Degradation•Deforestation

Biodiversity change•Extinctions•Domesticates•Invasives

Populationgrowth

Urbanisation•Coastal trend•megacities

Human development•Poverty alleviation

•Per capita consumption level

•Education

Technology development•Fossil fuel based energy systems•Tranport systems•High-input agriculture•Medical technology

Economic development•Globalisation of trade

Marine resources•Overfishing•Pollution•Habitat damage

Non-human factors•Orbital forcing•Solar activity•Tectonics etc

2. The world is a complex, coupled human-ecological system

• Bode’s Law- When you suppress the high-frequency, small disturbances in a

system, the amplitude of the low-frequency events increases- Examples:- River canalisation often leads to bigger floods (hurricane Katrina)- Fire suppression leads to uncontrollable conflagrations (Victoria)- Financial securitisation instruments led to a meltdown (bank crisis)

• Overconnectivity- As connectivity in systems exceeds a critical threshold, it becomes

much more likely that shocks will propagate through them- Examples:- Global pandemics: AIDS, SARS, H1N1- Global speculative bubbles and consequent deflation

Can developing countries rise to an acceptable level of human development without overloading the global environment?

WWF 2008 Africa : Ecological Footprint and Human Wellbeing WWF– Gland, Switzerland and Global Footprint Network (GFN), Oakland, California USA.ISBN 978-2-88085-290-0

Human Development Index

Eco

log

ical

fo

otp

rin

t

Adapting to a hotter, stormier future

Africa projections2080-2099, 21 models, A1B scenario

+4ºC+2 ºC-20%

+20%

Temperature Rainfall

Source:IPCC AR4 WG1 ch 11

Food supply in

southern

Africa

Fisher, G et al (2002) Climate Change and Agricultural Vulnerability IIASA

Observations: Fires in forestry plantations in southern Africa

Predicted wave run-up as a result of sea level rise and storm changes

Requirements for predicting coastlines include: Improved understanding of interconnected coastal/physical processes (e.g. the interaction between sea-level rise and changing storm intensities); An accurate profile response model.Drawing a contour line is insufficient: E.g. more realistic run-upprediction techniques are required as illustrated in the figure above.

Present storm run-up linePot. future storm run-up line due to SLRPot. future storm run-up line due to SLR & wave increase

Adapt or mitigate?

1 3 4 5 62

(Global equilibrium temperature – preindustrial temperature) ºC

Cost ofImpact andMitigation

% of GlobalGDP

Alreadyincurred

Commit-ted

11

5

Total cost curve

The effect of procrastination

1 3 4 5 62

(Global equilibrium temperature – preindustrial temperature) ºC

Cost ofImpact andMitigation

% of GlobalGDP

Alreadyincurred

Commit-ted

11

5

Total cost curve

Mind the gap!Emissions from South Africa through 2050

Graphic: SA Long Term Mitigation Scenarios (2007)

Staying competitive in a low-carbon economy

Co

st o

f m

itig

atio

n (

R/t

CO

2eq)

200

0

-50

100

4 8

Mitigation achieved (billion tonnes CO2-eq)

% of gap between ‘Growth Without Constraints’ and ‘Required by Science’

0 3010 20

‘For free’ ‘Technology tweaks’ ‘Market measures’‘Fairy

godmother’

Co

st o

f m

itig

atio

n (

R/t

CO

2eq)

200

0

-50

100

4 8

Mitigation achieved (billion tonnes CO2-eq)

% of gap between ‘Growth Without Constraints’ and ‘Required by Science’

0 3010 20

‘For free’ ‘Technology tweaks’ ‘Market measures’‘Fairy

godmother’

Many mitigation options exist

Year2003 2050

2

1

0

Em

issi

on

s (b

illi

on

to

nn

es C

O2e

q)

Growth without constraints

Required by science

Technical solutions

Two bridges are needed to close the gap

Technicalbridge

Ethicalbridge

• 3 C mean global temperature rise is regarded as ‘dangerous climate change’- We have already incurred 0.7 C and are committed to

~ 1 C more- Staying below 3 C will require global emissions to

peak by ~ 2020, then decline to below half of 1990 levels by 2050• If developed countries are to get room to increase

their emissions initially, developed countries need to decrease theirs by 90%

• Polar regions, small island states, Africa, the Amazon and coral reefs suffer serious damage by that stage

• If we aim at 3 C, there is a high chance we will actually exceed it

Persuading the world to take unified action to keep global warming tolerable

© CSIR 2009 www.csir.co.za

bscholes@csir.co.za012 841 2689