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2004 Tsunami - Population-environment interactions

Undersea megathrust earthquake

00:58 on Sunday 26th December 2004

Epicentre of the West Coast of Sumatra, Indonesia

9.1 - 9.3 magnitude

227, 898 deaths

one third of the dead were children

9,000 tourists dead

Sweden, 543 dead

Environmentalists measure strength/frequency of an event or the risk of occurrence, while social scientists often focus on the 'body' as the key metric in the demography of disasters.

'Exposure' = direct experience of environmental or social stress

Sensitivity and Adaptive Capacity

'sensitivity' to hazards is not the same as exposure

different sensitivity depending on their occupation - agricultural worker - high sensitivity but an office worker will have a lower sensitivity.

'Adaptive capacity' is the ability of a system (env or social) to evolve to accommodate environmental change

What determines adaptive capacity?

Resources

Education/skills/training

'Mindset'/personality (do communities as well as individuals vary in their mindsets?

New Environmental Threats to Population

Climate change will affect:

A) Coastal populations

B) Health

C) Imbalanced Hydrological Systems

D) Disruption of Agricultural Systems

Major natural castrophes

250 between 1950-99

killed 1.4 million people

Mostly wind storms and floods (90% of total)

Impacts are spatially uneven: loss of life greatest in Asia

economic loss greatest in North America and Japan

How do natural catastrophes relate to population issue?

pop growth means more people are living in vulnerable environments than ever before

human populations are responsible for changing the environment and this sometimes has disastrous consequences

population numbers affect consumption of natural resources and labour supply for production. In turn, these affect ecosystems and migration patterns (migrations towards cities in coastal areas especially)

Impact of Population on the environment

I = PxAxT

I = environmental impact

P = population size

A = affluence (consumption per head)

T = technology

It is clear that slowly population growth is a key part of an strategy to reduce humanity's impact on the environment

Impact of Population in Carbon Emission Rates

Emission rates = PxIxExC+D

P = population size

I = income per capita

E = Energy use per capita

C = carbon intensity

D = Carbon emitted from deforestation

Old Malthusian

Robert Thomas Multhus

Essays on population 1798 and 1803

He claimed population growth is geometric; expansion of resources is arithmetic

Therefore population growth will outstrip resources (e.g. land, food etc) producing Malthusian checks = war, vice and misery

Over last 15 years, population growth has been primarily seen as a threat to survival - global environmental catastrophe

As a result:

A) calls for slower population growth

B) discussion of pollution trading

C) greater sensitivity to growing number of environmental crises

Alternative Perspective:

People could be seen as the 'ultimate resource'

why argue for lower rates of pop growth when demographic transition is well advanced and when reductions in Western consumption levels could have the same effect in reducing environmental stress.

Pollution trading suggested inequalities in the value of life and ignores the onus to decrease pollution levels.

Human Reasons for the Increase in 'natural catastrophes.':

increased numbers mean exposure of more people to environmental risk

higher population densities in vulnerable locations - impacts worse

technology - settlement of more extreme environments with higher risks

Impact on populations of environmental change is uneven - those most affected being those who are most sensitive and have the least adaptive capacity.

Population growth has contributed to increasing numbers of vulnerable people

Social, economic and cultural factors have positioned these peoples in the most hazardous environments

Mobility is one form of 'adaption' but the poorest (those with limited capital) are at the least likely to move in the face of 'environmental risk'.

Malthus

argued that an increase in fertility would, in time, lead to an increase of labour supply and a decrease in the real value of wages relative to food £'s.

as wages decrease, either natural adjustments would occur, or a demographic crisis would ensue.

a decrease in mortality would have similar effects on population growth and would trigger a decrease in real value of wages.

Critique of Malthus

Gave no reason as to explain why food supply would increase arithmetically. History points to phases of rapid growth in food production followed by phases of slow growth

After the IR, fertility rates no longer rose with real income

Food production does not need to take place in the same place as it is consumed

Is famine and starvation a population of a poverty problem?

Food shortages

not necessarily associated with areas of limited food production

Most serious problem - countries which can neither grow enough nor have the purchasing to buy the food they need

Factors contributing to food price variations:

climate change - increase in floods/drought - affects subsistence farmers

countries like China - buying more grain to produce meat for the wealthier elements of their populations

Biofuel production soared - less cereal production for food

Major world recession from 2008 produced huge instability in international financial markets and speculative investment in commodities including food

2008 - political unrest in 30 countries linked to rising cost of living

Slash & burn

200 million people's livelihood

involves

labour

land

capital

market

low labour inputs

low capital inputs

low population densities - highly efficient means of cultivating crops in the equatorial forest.

Boserup

argued that an increased population density was a key trigger of agricultural innovation

human activities adjust rationally to environmental oppurtunites

at low population densities in equatorial forests, forest fallow systems including slash burn agriculture is logical - offers adequate returns to labour

at higher densities, innovation is necessary to support the population (e.g use of animals to draw a plough)

produce more food in total, but offer poorer returns to labour.

necessity becomes the mother of innovation

Environmental processes

MALTHUS