1. GLOBAL WARMING
© 2016 Paul Billiet ODWS

2. Is it really getting warmer?
1979
2003
© 2016 Paul Billiet ODWS

3. The melting Arctic ice
The length of the melt season inferred from surface temperature weekly data has been increasing by 9, 12, 12, and 17 days per decade in sea ice covered areas
© 2016 Paul Billiet ODWS

4. The oceanic conveyor belt
© 2016 Paul Billiet ODWS

5. The consequences
Sea level rise Flooding coastal areas Reduced agricultural land Displacement of populations
Climate change Displacement of ecosystems Change in range of insect vectors of pathogens Reduced biodiversity.
© 2016 Paul Billiet ODWS

6. The consequences Increased rates of photosynthesis
Increased agricultural production at high latitudes
BUT faster growth means: less protein in cereals trees taller are more exposed to storm damage.
© 2016 Paul Billiet ODWS

7. Knock-on effects Increased temperature melts the permafrost
Frozen plant remains decompose
More methane released
Similarly soils will lose organic carbon (humus) more rapidly in a warmer climate
Ice caps melt more sea exposed
Snow reflects light (high albedo)
Water absorbs light, increases warming
More CO2 dissolving in water lowers pH
Currently this is buffered and remains stable
Eventually pH will drop sea life will die CO2 produced as organisms decompose.
© 2016 Paul Billiet ODWS

8. Methanogens
Methanogens are anaerobic bacteria that produce methane gas
They can be used as sources of biogas gas, renewable energy source.
ucla genomics
© 2016 Paul Billiet ODWS

9. Methanogens and the greenhouse effect
50% of methane produced is used up as energy by other bacteria
50% is lost to the atmosphere (600 M tonnes y-1) where it acts as an important greenhouse gas
More rice paddy fields and pasture for grazing animals = more methane produced.
DAF Shiga Pref.
© 2016 Paul Billiet ODWS

10. Warming up the brew
As global warming progresses the permafrost will thaw in the regions covered by tundra
Tundra contains extensive reserves of frozen peat
As the peat warms and melts, it will provide a source of material for methanogens.
© 2016 Paul Billiet ODWS

11. The knock on effect
The amount of methane release into the atmosphere will accelerate
This in turn will drive global warming even further
Peatlands form 20-30% of organic C in N. Hemisphere.
UNEP
© 2016 Paul Billiet ODWS

12. Is it really true? Climate change skeptics
The climate has changed before
It’s the Sun
It is not that bad
There is no consensus
It is cooling
Models are unreliable
The temperature record is unreliable
Animals and plants can adapt
It has not warmed since 1998
Antarctica is gaining ice
Ice age predicted in 1970s
CO2 rise lags temperature
© 2016 Paul Billiet ODWS

13. What can be done? Reduce carbon emissions
Improve mass transport systems (public transport)
Design more efficient motors
Design alternative power sources
Hydrogen powered motors
BUT problems of fuel reservoir, delivery, fabrication
Renewable energy (wind, tidal, hydro, geothermal, biomass)
BUT growing crops for biofuel reduces farmland available for food Hydroelectric dams disrupt river ecosystems
Nuclear power
BUT problems of nuclear waste treatment/storage.
© 2016 Paul Billiet ODWS

14. What can be done? Increase natural CO2 sequestering
Reduce deforestation
Increase reforestation
Reforestation Peru
© 2016 Paul Billiet ODWS

15. What can be done? Artificial CO2 sequestering
Filter CO2 sources using hydroxide scrubbers
Injection of CO2 into deep ocean layers Forms CO2 reservoirs Impact on sea life unknown
Injecting CO2 into disused oil wells
Mineral deposition as carbonates.
© 2016 Paul Billiet ODWS

16. Artificial CO2 sequestering
© 2016 Paul Billiet ODWS

17. The bottom line Two factors will ultimately govern what happens:
1. Human population growth
More people means greater demand for non-renewable resources
2. The ecological footprint of each individual human
Higher standards of living usually means higher consumption of fossil fuels
The planet will look after itself in the end
There are plenty of examples where human communities have disappeared because they outstripped the environmental resources.
© 2016 Paul Billiet ODWS

18. The planet will look after itself in the end
Rapanui (Easter Island) in the Pacific
Settled between AD900 and 1200
Community in severe decline AD 1700
Cause: excessive deforestation
© 2016 Paul Billiet ODWS

19. The planet will look after itself in the end
Chaco Canyon, New Mexico
Anasazi culture
AD 850 – 1250
Cause: Deforestation combined with a decline in rainfall
© 2016 Paul Billiet ODWS

20. The planet will look after itself in the end
Mesopotamia
Sumerian civilization
3100 – 1200 BC
Increased salt levels in soil due to irrigation systems & arid environment
Reduced food yield
© 2016 Paul Billiet ODWS

21. The planet will look after itself in the end
Greenland
Viking colony
AD982 – 1350
Cause: Deforestation, soil degradation & cooling of the climate
© 2016 Paul Billiet ODWS

22. Who’s next? © 2016 Paul Billiet ODWS
forumpolitics.com/pics/earth-photo.jpg
© 2016 Paul Billiet ODWS