Coaching Centre
Chapter 7: Global Systems Notes
Earth as one connected system: the atmosphere, hydrosphere, lithosphere and biosphere, ocean currents and the drivers of Australia's rainfall, cyclones and eruptions across the spheres, the phosphorus and oxygen cycles, Earth's energy budget and the greenhouse effect, the evidence for climate change, its impacts including sea-level rise, and how the world is responding.
Sections
-
7A Earth's spheres as one system Mastered
The atmosphere, hydrosphere, lithosphere and biosphere as one connected system; the layers of the atmosphere and why temperature falls then rises with height; how photosynthesis built today's oxygen-rich air; and thinking about Earth in terms of stores, flows and feedbacks.
-
7B Ocean currents and the global conveyor Mastered
Wind-driven surface currents around Australia, including the East Australian and Leeuwin currents; the deep thermohaline circulation driven by temperature and salinity; upwelling and marine food webs; how currents move heat; and why a warming, freshening ocean could slow the conveyor.
-
7C Oceans, winds and Australia's rainfall Mastered
How the Walker circulation, El Niño and La Niña, the Indian Ocean Dipole and the Southern Annular Mode link the oceans and atmosphere to drive Australia's droughts and floods, how forecasters track them, and how Australia's rainfall pattern is shifting.
-
7D Natural events across the spheres Mastered
How volcanic eruptions, earthquakes and tropical cyclones send effects through all four spheres: volcanic cooling and the Hunga Tonga eruption, liquefaction and tsunamis, how cyclones form, their structure, categories and storm surges, and how a warming climate is changing them.
-
7E Phosphorus, oxygen and water cycles Mastered
How phosphorus cycles slowly through rock, soil, living things and the ocean; why Australia's ancient soils are so phosphorus-poor and how native plants cope; peak phosphorus and recycling; the oxygen cycle and ozone formation; and measuring transpiration in the water cycle.
-
7F Earth's energy budget and the greenhouse effect Mastered
How sunlight in balances infrared out in Earth's energy budget, why gases such as carbon dioxide, methane and water vapour absorb infrared, the natural and enhanced greenhouse effects, Earth's current energy imbalance, climate feedbacks and climate sensitivity, and the limits of the classic jar experiment.
-
7G Reading the climate record Mastered
How scientists reconstruct past and present climate from thermometers, tide gauges and satellites and from proxies such as ice cores, tree rings, corals and lake sediments; what the records show; the fingerprints that identify human causes; and how climate models are tested.
-
7H Impacts and rising seas Mastered
The observed and projected impacts of climate change in Australia, why sea level is rising and by how much, what it means for low-lying communities such as the Torres Strait Islands, First Nations memories of past sea-level rise, extinction and biodiversity, and adapting to change.
-
7I Responding to global change Mastered
How the world and Australia are responding to climate change and other global problems: international agreements from Montreal to Paris, the carbon budget, Australia's emissions and targets, ways to cut emissions in each sector, waste and plastics in global systems, e-waste, and bringing species back from the brink.
-
7J Global systems review Mastered
A summary of the whole Global Systems chapter, key words, and a mixed test covering Earth's spheres, ocean currents, ENSO and the IOD, cyclones and volcanoes, the phosphorus and oxygen cycles, the energy budget and greenhouse effect, the climate record, impacts and sea level rise, and responses to global change.