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Contemporary Human Impacts

global

profound

swift

hyper-connected

often irreversible

Prehistoric Human Impacts

local

limited

slow

unconnected

mostly reversible

Perfect Storm Scenario

Set of interconnected, threatening issues

climate change

freshwater crisis

energy security

food security

pollution

Prof. John Beddington predicted in 2008, that by 2030:

Population - 30% increase

Energy - 50% increase in demand

Food - 50% increase in demand

Water - 30% increase in demand

Human influence/control of fundamental planetary systems:

Carbon cycle (amount of CO2 going into the atmosphere, and CH4 (methane) - cows etc.

Nitrogen cycle

Atmospheric and ocean chemistry (ocean acidity from CO2)

Hydrological cycle

Cyrosphere (Glaciers, sea ice etc)

Biosphere (extinctions, deforestation)

THE ANTHROPOCENE

Suggested that it began in 1800 - Industrial Revolution - increased and extensive use of fossil fuels - coal etc.

The A implies that one species (humans) are terminating the Holocene and creating a new planetary era of instability, unpredictability and extremes.

Not entirely new idea - has been suggested before in 1873 & 1983 by Stoppani and Nilsson.

Little evidence back then, however there is great evidence now due to increased populations, the economy and energy.

From 1800 - 2000

Global population: increase x6

Global economy: grew x50

Global energy use: increase x40

The 'Great Acceleration'

50% of all accessible water is used by humans

20% of mammal species, 10% of bird species and 5% of fish species are threatened with extinction due to human activities.

Unbalances Nitrogen and Carbon cycle.

2013: atmospheric CO2 exceeded 400ppm, highest in 3 million years

"Earth is now a human planet"

"We no longer live in a natural world...humans are now the largest single source of change on the planet."

4/10ths of planet's land surface is used to grow our food

3/4 of Earth's freshwater is controlled by us

When did it begin?

Industrial Revolution

OR

Neolithic Agricultural Revolution - 6000 years ago

Many think it could have started in the latter part of the 18th century when analysis of air trapped in polar ice showed the beginning of growing concentrations of CO2 and CH4

This date also happens to coincide with James Watt's design of the steam engine in 1784.

During past 3 centuries

human population reached 6 billion and expected to reach 10 billion by end of this century

Methane producing cattle population has risen to 1.4 billion

30-50% of planet's land surface is exploited by humans

Tropical rainforests disappearing - releasing CO2 and causing extinction of animals

Dam building and river diversion

160 million tonnes of atmospheric sulphur dioxide emissions per year

More nitrogen fertilisers are applied than is fixed naturally in terrestrial ecosystems

These effects have only been caused by 25% of the population

Nature:

[noun] all the animals, plants, rocks etc in the world and all the feature, forces and processes that happen, exist independently of people.

Nature/Culture in the A

Nature organises our knowledge about the world & our institutionalised responses to it

Physical processes are stable, predictable and knowable - function independently of social life & without consciousness

In contrast, most of the social world is understood as reflecting decisions of human beings

Environmentalism is no longer about saving nature alone, it is also about saving people given that we are dependent on nature.

Environmental problems are often symptoms of deeper social problems

Famine

Ethiopia 1984-85

Almost 1 million died

El Nino and production of famine

El Nino/El Nina is the cyclical warming and cooling of waters off the pacific coast of South America

Impacts precipitation patterns, temperatures and weather events around the Pacific

1768 - 1769 - year of El Nino

There was a decline in precipitation and therefore a decreased in crop production in Bengal

10 million people had already died by the time rain returned in 1770

Calcutta was the admin centre of the British East India Company (BEIC) who controlled national, regional and local political affairs

Indian markets flooded with products from British Industrial revolution

This meant the disruption of local economies which meant that people had to move to work in the export economy (largely agricultural)

BEIC ensured Bengal switched to growing of commercial introduced crops rather than traditional local crops

However, commercial wheat is more vulnerable to drought that traditional Bengal crops

There was a decrease in wheat yield and a decreased in BEIC revenue

BEIC increased the land tax rates from 10% to 50% of agricultural produce

At the height of the famine in 1770, they increased the tax by a further 10% to pay for the expansion of colonial infrastructure

The company hoarded grain to ensure that there was no disruption to the London markets

Grain exports continued to grow and local food prices rose hugely

BEIC profit doubled between 1765 - 1770 BUT the company and the British Gov (shareholder) did not acknowledge the issue.

1877-1879 famine again in Bengal (10 million deaths)

1877, BEIC controlled an annual surplus of 5.16 million tons of rice and grain and exported over 1 millions tons.

Famines were not caused by a lack of food, but by how a set of colonial economic and political practices changed the biogeography of the region - displacing native crops

The economic fortunes of the British Empire came first over the lives of their subjects

The way that social and physical systems interact is central to understanding these historic famines

Anthropocene

How the anthropocene killed nature/CRISIS OF ANTHROPOCENE