The Anthropocene: past, present and future predictions Flashcards
Who originally proposed the anthropocene?
Paul Crutzen 2000
What did Paul Crutzen call the anthropocene?
the time interval in which human activities now rival global geophysical processes
What fossils of humans might there be?
Techno-fossils= plastics
Fossils of livestock
What is the earliest believed start of the anthropocene?
Megafunal extinction by early human hunters before the holocene
What megafauna was present in Europe and northern asia?
Woolly mammoth
Woolly rhinoceros
Cave bear
Giant deer
What north american megafauna was present?
Columbian mammoth
Shasta ground sloth
Giant ground sloth
Mastodon
Yesterdays camel
Sabre tooth cat
What Australian megafauna was there?
Short-face kangaroo
Marsupial lion
Diprotodon
Giant kangaroo
Giant short faced kangaroo
What south American megafauna was there?
Litoptern
Glyptodon
Notoungulate
Besides humans what might have been another reason for the death of megafauna in the holocene?
Rapid climate changes linked with Henrich events and D-O events
How did Ruddiman define the Anthropocene?
Early anthropogenic warming - suggesting land clearance and flooding for rice farming
What did the human transition from hunter gatherer to farming settler cause in the holocene?
5000 years ago artificial wetlands increased wetland and methane production and CO2 from land clearance
How did steffen argue the start of the Anthropocene?
Industrial Revolution around 1800 provides a logical start date for the new epoch
When was the biggest transformation by humans?
post ww2 in a process called the great acceleration
What is the Suess effect?
the isotopic signature of CO2– which records the increasing input of ancient plant material (old ‘dead’ carbon, which lower radiocarbon values)
Why is the carbon getting lighter?
humans are burning more plant material with the change from mainly coal to oil and gas as well
How is carbon 14 produced in the atmopshere?
cosmic rays collide with atoms in upper atmosphere producing a neutron which collides with nitrogen to produce a proton and C14
What do technology do some regard as the start of the Anthropocene?
the nuclear bomb
What came into effect in 1962 that affected the levels of radioisotopes in the atmosphere?
the nuclear test ban treaty which meant the soviets did multiple large tests in 1962
Where does the C14 from nuclear explosions go?
stored in stalagmites which can act as record of humans in the future
Where does the yearly fluctuation in atmospheric CO2 come from?
The growth and die back of vegetation in the northern hemisphere
Why is it that global co2 is affected by NH vegetation?
this is where most land mass is along with large deciduous forests which absorb carbon in the summer and then fall as leaves (stored carbon) in autumn
What is the rate of change of CO2 ppm?
1.5ppm per year
Why is it unlikely volcanoes are the main cause of climate change rather than humans?
Volcanoes 242 million tonnes a year humans 29 billion tonnes
What do we know is a link to increasing atmospheric co2 due to humans?
burning fossil fuel (since the industrial revolution)
What is the % increase of ghgs since the industrial revolution?
CO2- 40%
N2O- 20%
CH4- 230% (25-100 times more potent)
How are ghgs today compared to 800,000yrs ago?
Higher concentrations
Changing at a faster rate
What will co2 ppm be in 2100 if we continue as usual?
900
How was cherry picking used to put across the zombie climate idea of temp trending down since 1998?
Lord Lawson who picked data from an el Niño and La Nina and said temp had stabilised (ignoring long term change)
What is a important example of natural variability in climate change?
El Nino and La Nina which occurs in the south pacific and controls weather patterns and upwelling locations
What are the features of general circulation modelling?
1) Never get the exact same result if model run twice
2) Can reproduce current climate well
3) Models improving for past climate reproduction so more confidence for future prediction
Why are climate models more reliable then weather forecasts? (wave analogy)
Think of weather as trying to predict the height of the next wave at the beach and the climate as the tide tomorrow
What was the first extreme event that really got people to notice climate change?
Hurricane Katrina 2005
What is climate change going to do with the number of extreme events?
Make more powerful evens more frequent i.e., 1 in 100 yr now 1 in 10
What is the link between high CO2 levels and ice sheets?
Melting
How will the rate of melting of ice sheets occur with increased CO2? (rate)
Will start slow with offset from interior growth
Is climate change to expensive to deal with? (zombie argument response)
No as we can bail the banks to afford to de-carbonise our infrastructure
What are the obstacles to financially sorting climate change?
Energy system heart of economy
Mainstream politics
Neo-liberal economics
No defined enemy
Age of fear and austerity
Goldfish attention span (hard to put complex ideas across)
