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The Need for Action -evidence for global warming,
hope for solutions
Geoff DaviesVisiting Fellow
Earth Sciences, ANUAuthor: Economia
Is global warming still happening?
• Yes, it’s the long-term trend.
•Note pauses 1980s, 1990s.
• 2010 equal warmest-ever, so far.
What about cooling 1940-1970?
•Due to
• industrial soot and dust
• cooling North Atlantic ocean
TextText
Mainly in northern hemisphere
Are we causing global warming?
•Consistent with predictions from 20-30 years ago
•Many lines of evidence
•well-established physics (100+ years)
•measured patterns of warmth in atmosphere
•the past
•models - disputed but consistent
Indications from the past•Collective estimates from
• ice ages
• volcanic eruptions
• past warm episodes
• sediment records
Result: 3-4°C (or more) per doubling of CO2
•Complex interactions:
•different species respond differently
•some decline - extinctions
•some increase - plagues
•trees migrate slower than birds - ecosystems ripped apart
•Total effects impossible to predict
Consequences? Many.•Ecosystems
Is there any hope?
•Yes -
•with good policies, cost to economy small (<1% GDP)
•eliminating waste is the quickest, most cost-effective option - start tomorrow
•many technologies available already
•We can accept remaining difficulties as a challenge, not a reason to dither
Cost of 60% emissions reduction:9 months longer to double
GDP
Steve Hatfield-Dodds, CSIRO
No actionEarly action
Reducing waste
• Available now at zero or moderate cost:
• Building energy efficiency: quadruple
• Vehicle fuel efficiency: double
• Household electricity use: one quarter
• Water efficiency double (or more)
• . . .
Eliminating wasteRedefine waste: as nutrient
(Cradle-to-cradle design)
Carpet nutrient Battery nutrient
Interface Carpet Inc. - efficiency gains
• Broadloom to tiles: x5
• Recyclable polymer:
• 2/3 the material: x1.5
• 4 times as durable: x4
• Total gain x30 (97% material reduction)
• After 4 years:
• Revenues doubled
• Employment nearly doubled
• Profits tripled!