Global environmental change = GEC
GEC is well described in common and popular literature
● Silent spring
○ Rachel Carson
○ About the growing influence of pesticides on insects and birds
● Limits to growth
○ Club of Rome
○ A computer model simulating future development of the earth
GEC problems:
● Growing human pressure
○ 20% of world's population owns/uses 80% of world's natural resources =
20/80 dilema
● Climate change
● Ecosystem decline
● Surprise
○ Change can happen unforeseen
Impact = Population * Affluence * Technology
↳ GDP per capita
Many driver of change are growing leading to increasing GHG concentrations.
All this growth is exponential, so a solution would be bending the exponential curve by
stabilizing and bringing it to sustainable levels.
All spheres interact with each other.
Earth’s system = interaction of physical, chemical and
biological cycles and energy fluxes that provide life
support.
In earth's history there always has been change, however the time scale of change is
speeding up.
1. Long past
● The start of the earth was 4.54 billion years ago
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, ● Evolution of atmospheric oxygen
2. Ice ages 1 000 000 YBP
● Milankovitch cycles
○ Eccentricity
■ = change in the earth's orbit around the sun
■ Every 100 000 years
○ Obliquity
■ = change in the earth’s tilt
■ Every 41 000 years
○ Precession
■ = change in the earth’s wobble
■ Every 25 000 years
3. Modern humans 200 000 YBP
4. Industrial revolution 250-150 YBP
● Coal → more energy
● Better mining technology
● Fertiliser → agricultural productivity
● Improved transport
● Machinery → Efficiency
● Mass production
↳This resulted in:
● Growth of average income
● Population growth
5. Start anthropocene 0 YBP
● Today we live in a new geological era = Anthropocene
↳ Global change due to humans
● The Brethon Diagram (1985) shows how we see earth system today.
6. Future 100 YAP
Systematic change = change manifested globally
Cumulative change = change manifested locally
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, Research approaches:
● Curiosity
● Experiment
● Models
● Observation
● Theory
Precautionary principle = taking action without having the evidence that there even is a
problem.
Types of uncertainty
● Accuracy Proper ranges
● Ignorance Lack of knowledge
boundaries
● Inexactness miss perception of system
components
● Precision Proper values
● Unreliability Lack of confidence
model/measurement
Sources of uncertainty:
● Completness / comprehensiveness
● Definition of concepts
● Experimental set up
● Input data and assumptions
● Realism of model / experiment
● Structure
L4: Demographics of global environmental change - Hilderink/Hofstra
Sustainable development = development that meets the needs of the present without
compromising the ability of development of future generations
Population and health are important for sustainable development.
Population
● is growing with an exponential grade, which depends on 3 factors (see demographic
change)
● Growth differs in different regions of the world
● Urban population is expected to grow
Important aspects of population:
● Size
● Place
Population demographics change due to:
● Fertility
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