Environmental Science

• Environmental science


  Interdisciplinary study of the environment's processes and its systems, how people are affecting the environment, and how to solve environmental problems
• Environmental science


  • Follows scientific method: Observation, question, hypothesis, experiment, conclusion, result
• Industrial revolution


  1800s
• Publication of Silent Spring by Rachael Carson


  1960s
• Concern over state of waterways

  1970s
• Acid rain in Europe and North America


  1970s
• Chernobyl nuclear disaster


  1986
• Lead in petrol


  Late 1970s onwards
• The Paris Agreement


  2015
• Great Acceleration


  Post 1950s- human induced change and global economic activity. Improved standards of living but resulted in environmental degradation
• Global environmental challenges


  • Climate change
  • Loss of biodiversity
  • Overuse of natural resources
  • Human health and wellbeing
• Climate change


  • Caused by increase in human activity, consumption, production of waste and air pollution, greenhouse gas effect and global warming
• Loss of biodiversity


  • Changes in land and sea use
  • Direct exploitation of organisms
  • Climate change
  • Pollution
  • Invasive alien species
• Loss of biodiversity in New Zealand

  • NZ is a biodiversity hotspot due to its isolation since the split from Gondwana (80 MYA), enabled organisms to evolve over the diverse habitats
• Overuse of natural resources


  • Driven by global demand for resources and development (urbanization)
• Human health and wellbeing

  • Biodiversity is important for well-being, resource use is inequitable, benefits and burdens are unfairly distributed
• Ecosystem services


  • Provisioning - e.g., the production of food and water
  • Regulating - e.g., the control of climate and disease
  • Supporting- e.g., nutrient cycles and crop pollination
  • Cultural - e.g., spiritual and recreational benefits
• Rapid urbanization and development is rapidly occurring due to a range of factors (Great acceleration 1950s, increase pop size). Subsequent increase of natural resource use, resulting in environmental challenges. Important to recognise how these challenges are connected and have detrimental impacts on our ecosystems
• Environmental science is an interdisciplinary which strives to explore and address these challenges
• Atmosphere


  Troposphere, stratosphere, mesosphere and thermosphere
• As you move up the atmosphere

  The temperature decreases due to the decreasing density
• Stratosphere


  The warmest zone and is where the ozone layer is
• Speed of particles is greater in the stratosphere


  There is lots of collisions and energy produced
• Atmospheric stability and instability

  1. Parcels of hot air rise, expand and cool, becoming less dense

  2. Rate of cooling is less if water vapour in the air mass starts to condense

  3. If the air parcel is warm enough there are a high number of collisions, and the water remains in gas form

  4. As the air mass expands and the number of collisions reduces the amount of heat reduces, and water vapour drops back into water form

  5. Each time a change occurs, such as gas to solid there is energy produced
• Absolutely unstable


  Hot air rises (to some extent as there are usually lower temps than the parcel higher up)
• Conditionally unstable


  In between absolutely unstable and absolutely stable
• Absolutely stable


  The air is cooler and does not rise
• If the airmass is unstable and goes up


  It expands and cools off, resulting in moisture and rainfall
• If the air mass is stable


  It rises and there is no rainfall
• Inversion


  Occurs when there is significant cooling close to the ground level, however warmer air above. Thus, the air does not rise and the pollution/smoke within it remains trapped beneath the overlayer
• Pollutants trapped in inversion

  • Photochemical smog
  • Carbon dioxide
  • Particulates like ash, dust
• If there are high levels of PM 2.5 present, this can be extremely dangerous as it can clog lungs. PM 10 is another main measurement
• The World Health Organisation has a warning measurement system for PM emissions
• Christchurch used to have some of the worst air pollution in New Zealand, primary source was coal and wood burning
• A positive implication of the earthquakes is that air pollution is reducing due to getting rid of chimneys and transitioning to other heating methods
• Air pollution is more common in winter


  There is cool air at ground level, particularly during the mornings, as the sun's rays warm the surface above it. Thus, the air below is cooler than the air above, which results in an inversion effect
• Understanding wind patterns is important in determining where the pollution is coming from/how it can spread
• Pollution can travel thousands of kilometres and China is the biggest contributor of pollution on the planet