A Very Short Introduction to Climate Change- M. Maslin

The PDF version of the book can be found here.

Chapter 1- What is global warming?

  • What determines the earth's climate?
    • Climate is controlled by 3 things: mass, distance from the sun, and composition of the atmosphere
      • Mass: a larger mass has more gravity and can hold an atmosphere
      • Distance from sun: closer = warmer
      • Composition: every gas absorbs a different wavelength of radiation. Greenhouse gases reflect longwave radiation onto the earths surface, causing it to heat up.
    • Humans have no control of the 1st 2, but it is by changing the 3rd that global warming is triggered
  • How do we measure past climates?
  • What is the IPCC?
    • Intergovernmental panel on climate change
    • There are 3 groups and a task force
    • Write reports verified by 400 experts from 120 countries
    • Compare the warming potential of different gases
  • What are the different predictions for climate change?
    • a- linear/synchronous response
      • Climate change is directly proportional to CO2
    • b- muted response
      • Climate is insensitive to CO2
    • c- delayed response
      • Slow, then accelerated change
    • d-threshold response
      • No response until a certain point, then an immediate response
Chapter 2- History of the climate change hypothesis
  • Global warming was ignored or refuted for a number of years, and it was only in the late 80's that international environmental awareness was discussed.
  • the main reason people argued against it was because of problems with the data
    • land monitoring was affected by the UHI
    • method change for testing sea surface temperature
      • as boats got bigger, more water evaporated when the bucket was hoisted up the side
    • no explanation for the cooling of the 40-70s
    • satellites came closer to earth due to friction with the atmosphere
    • the models of the past don't match actual data
Chapter 3- Your viewpoint determines the future
These diagrams are very low quality, find them on page 41
  • There are 4 ways to interpret how nature responds to change:
    • Nature benign- robust, humans can't impact it
    • Nature ephemeral- fragile, unforgiving to change
    • Nature perverse- stable to a point of no return
    • Nature capricious- unpredictable, out of human control
  • How you perceive nature is linked to what you think will happen with global warming, and is based on your investments and upbringing





Chapter 4- Evidence for climate change
  • Proxy variable - a measurable descriptor that stands in for the desired (but unobservable) variable
  • Tempearature
    • Tree ring thickness is a proxy variable- thicker rings show rapid growth in certain conditions, indicating a warmer climate
  • Sea level
    • Sea level is hard to measure because it is afftected by more than just climate e.g. isostatic rebound
  • Permafrost
    • When the climate is so cold, the top layer of the soil freezes
    • The top metre is called the active layer
      • it gets warm enough to melt
    • the active layer is increasing
      • Methane is released (positive feedback) and the ground becomes unstable and susceptible to avalanches
  • Disproving sceptics:
    • Sceptics: All of the data has been tweaked to find the desired trend
      • Evidence: The data has to be adjusted to make it more accurate; however, even the raw data set shows the same trend
    • Sceptics: Sunspot activity is responsible for climate change
      • Evidence: To an extent, yes. But, it is not the sole cause
Chapter 6- What are the future impacts of global warming?
  • Coastlines
    • Rising sea levels result in shrinking and sinking coasts
  • Storms/floods
    • More heavy rainfall
    • Bigger monsoons
        • Continents are a lot warmer than the ocean in the summer
        • less snow in Tibet increases continental temperatures further
        • warmer climates mean the air can hold more water vapour
    • There will be more variability- storms will be harder to predict
    • there is no expected change with regards to hurricanes
  • El Nino
    • The southern oscillation is expected to be more frequent
    • Bjorn Lomborg (The Skeptical Environmentalist)- global warming could turn off El Nino
      • No evidence, but to be considered
  • Health
    • Less deaths as a result of the cold, but more due to overheating
    • Water shortages
    • Mosquitos
  • Agriculture
    • We don't yet know the impact of climate changes on food supply
      • Increasing temperatures bring water shortages, pests, and crop failures
      • But CO2 brings rapid growth and a quicker turnover
Chapter 7- Surprises
We assume global warming will be a linear increase, but we cannot know for certain- for instance, half of the total warming in Greenland occurred in 10 years
  • Deep ocean circulation
    • The Gulf Stream is responsible for moderating the climates of the USA, Europe, and West Africa
      • Without it, our seasons would be extreme
  • Gas hydrates
    • Methane is trapped in ice lattices at the bottom of the ocean and under permafrost (high pressure, and low temperatures)
      • If it melts, the methane is released in an explosion
        • Submarine landslides = tsunamis
        • Positive feedback, encouraging further climate change
      • Isostatic rebound in Greenland and Antarctica is releasing the pressure needed to hold it in place
  • The Amazon
    • If the Amazon gets too dry, it will die forming a Savannah
    • Savannahs hold less CO2, and are easily flammable
Chapter 8- Politics
There are a number of key players in discussions around climate change. Each group represents companies and countries- all of which have something to gain or lose from global warming.
  • G77 + China
    • Made of 77 developing countries
    • Reducing emissions results in reducing development
    • Carbon trading is positive, as it provides income
  • AOSIS (Association of Small Island States)
    • They want the tightest control on climate change as it will result in their extinction
  • JUSCANZ [Also called the Umbrella Group)
    • A group of developed countries
    • Concerned with the cost of reduction and abatement
      • A split in the group between oil dependent and eco-friendly countries.
  • EU
    • Work done should be in proportion to the level of development
    • A very democratic and slow decision making body
  • OPEC (oil exporters)
    • Understand that by reducing global warming, they will lose business and act accordingly
Chapter 9- Alternatives
  • Technofixes
    • Removal of CO2 from industry
    • Improve energy efficiency
    • Renewable energy
    • Afforestation
  • Industrial uses of CO2
    • Oil recovery
    • Food manufacture
    • Chemical manufacture
    • Metal reprocessing
    • Waste water processing
This was a VERY brief summary of some of the points I found most interesting, but the book gives a much more coherent and expansive explanation of the topics above.

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