GEOS2111 Hazards, Climate Change and Disasters

How GEOS2111 is assessed

These five components and their weights are what the University publishes on the unit of study page for the single 2026 offering, and they add to exactly 100 percent. The final written exam is the only component labelled a hurdle task, and no hurdle pass mark is stated in the unit materials available here, so confirm it on the outline. Four details differ between sources: the early feedback test has a published due date of 21 August 2026 where the assessment page gives only Week 3; it is described both as multiple choice and short answer and as 20 multiple choice questions; its scope is given as Weeks 1 to 2 in one place and Weeks 1 to 3 in three others; and one practical handout calls the group presentation 20 percent where four other sources give 15 percent. Weights come from the outline, dates from your own subject site.

Current GEOS2111 dates

Dates are as published in the unit of study outline and the unit's own teaching pages for this offering. Confirm exact deadlines and submission settings in the live LMS.

What GEOS2111 covers

GEOS2111 runs over thirteen weeks in three modules. Weeks 1 and 2 build the conceptual vocabulary: hazard, exposure, vulnerability, resilience, risk and disaster, and the frameworks that explain why identical shaking kills thousands in one place and nobody in another.

Weeks 3 to 10 work through the hazard families one at a time, each with its physical mechanism, its measurement scale and its management response, starting with the climate related hazards and ending in space. Weeks 11 to 13 turn to detection, monitoring and disaster management, closing on Australian bushfire case studies. A QGIS practical stream runs underneath the whole unit and feeds two of the five assessments.

The answer the unit builds is that a hazard only becomes a disaster when it meets exposed people and pre existing social conditions, so the unit spends its first two weeks on concepts and frameworks before it touches a single volcano.

Module 1, Weeks 1 and 2, fixes the working vocabulary of hazard, exposure, vulnerability, resilience, capacity, risk and disaster, then traces how explanation has shifted from divine punishment to physical process to political economy, and lands on the frameworks that carry that shift: the Pressure and Release progression of vulnerability, the triangle of vulnerability, the MOVE framework and the Sendai Framework for Disaster Risk Reduction.

Module 2, Weeks 3 to 10, is the hazard survey. It opens with weather, climate change and how climate is measured and projected, then takes the climate related hazards in turn, droughts and floods, heatwaves and bushfires, tornadoes and tropical cyclones, before moving to the geological ones, earthquakes, volcanoes, tsunamis and mass movement, and finishing with space hazards.

Each hazard gets the same three part treatment in the pre recorded lecture and the live lectorial: what the process is and how it is measured, what hazards follow from it, and how it is mitigated and managed, illustrated with case studies.

Module 3, Weeks 11 to 13, covers the geoscientist's role in detection, monitoring and mitigation, the data quality questions that come with geographic information for disaster risk reduction, disaster management success stories, and Australian bushfire case studies.

Running underneath all of it is a QGIS practical stream: an introduction to GIS in Week 1, coastal exposure and vulnerability mapping in Weeks 2 to 4, group presentations in Week 5, a seven part hazard risk mapping exercise on Hawaii across Weeks 7 to 10, a space weather communication scenario in Week 11 and a disaster simulation game in Week 12. Two of the five assessments come straight out of that stream.

Assessment is spread across an early feedback test, a group GIS presentation, a ministerial statement, an individual GIS assignment and a 40 percent final written exam that is a hurdle task, so the unit rewards steady weekly work and punishes leaving the exam to chance.

Worked example · free

Running a likelihood and consequence risk assessment on a coastal storm surge

Key terms

Hazard

A process, phenomenon or human activity with the potential to kill or injure, to harm health, to damage property, to disrupt social and economic life, or to degrade the environment. The unit follows the UNDRR terminology, which classes hazards as natural, anthropogenic or socionatural in origin. Natural hazards are usually extremes of an ordinary process: too much water is a flood, too little is a drought.

Exposure

The people, property, systems and other assets present in a hazard zone and therefore subject to potential losses. Exposure is a property of location and timing rather than of the hazard itself, which is why the same cyclone track produces different exposure in a national park and in a coastal city.

Vulnerability

The physical, social, economic and environmental conditions and processes that raise how susceptible a person, a community, an asset or a system is to the impacts of a hazard. It is a pre existing condition, present before the hazard arrives, and it explains why identical shaking or identical rainfall produces very different losses in different places.

Adaptive capacity

The ability of a system or community to adjust to change, moderate potential damage, take advantage of opportunities and cope with the consequences. It sits alongside vulnerability and resilience in the trio the unit uses to explain why losses occur or do not occur in a particular context.

Resilience

The capacity of an exposed system, community or society to resist a shock, absorb it, accommodate and adapt to it, transform where transformation is needed, and then recover promptly and efficiently, including by preserving and restoring the structures and functions it depends on. The unit treats it as a contested concept rather than a settled one, and expects you to say resilience for whom and to what.

Risk

The potential loss of life, injury, or damaged and destroyed assets that could occur to a system, society or community within a stated period, determined probabilistically from hazard, exposure, vulnerability and capacity. The compact teaching form used in the unit is risk equals hazard times vulnerability.

Residual risk

The risk that remains after controls have been applied. Naming it is a required step in a risk assessment: a control programme reduces risk, it does not drive it to zero, and pretending otherwise is how open days and field trips go wrong.

Hierarchy of controls

An ordered set of risk treatments applied strongest first: elimination, substitution, engineering controls, administrative controls and finally protective equipment. The order matters because only elimination removes the hazard; everything below it manages exposure or consequence and leaves residual risk.

Disaster

Quoted from UNDRR terminology (2017), which is the wording this unit uses: “a serious disruption of the functioning of a community or a society at any scale due to hazardous events interacting with conditions of exposure, vulnerability and capacity, leading to human, material, economic or environmental losses and impacts.” The definition is deliberately social: without disrupted people there is a hazard but no disaster.

Disaster risk reduction

The policy aim behind disaster management: to prevent new risk, reduce the risk that already exists, and manage whatever remains, in order to strengthen resilience and support sustainable development. It is the frame the Sendai Framework works within and the answer to the question of what to do once risk has been assessed.

Pressure and Release model

A framework that traces disaster back through three linked layers of social causation: root causes such as limited access to power, structures and resources; dynamic pressures such as rapid urbanisation, deforestation or lack of local institutions; and unsafe conditions such as dangerous locations and unprotected buildings. Pressure builds from the left and meets the hazard, and release means acting on the causes rather than the symptoms.

Indirect impact

An effect that appears later because of a direct effect, such as homelessness following the destruction of housing, unemployment following the destruction of workplaces, or illness following displacement and stress. Indirect impacts often exceed direct impacts in total cost and are the part of the ledger that recovery planning most often underestimates.

GEOS2111 FAQ

Questions students ask in each GEOS2111 chapter

What is the difference between a hazard and a disaster?

A hazard is a process that may cause harm; a disaster is a realised, serious disruption of a community or society. The gap between them is filled by exposure, vulnerability and capacity. A magnitude 7 earthquake under uninhabited desert is a hazard event and nothing more, because there is nobody there for it to disrupt. The same rupture under a dense city with unreinforced masonry housing and no functioning warning system is a catastrophe. This is not a semantic point; it is the organising claim of the whole unit and the reason Week 1 exists. It also has a practical consequence for how you write: an answer that explains losses by describing the physical event has answered only the first quarter of the question. The examinable move is to name the hazard, then name what was exposed, then name the conditions that were already there, then weigh the capacity to warn, evacuate and recover. Chapter 01 · Core concepts in hazard and disaster studies

Why does a hazards unit spend a week on the history of ideas?

Because the history is not settled, and both of its main products are still in use. The move from divine explanation to physical explanation to social and political explanation left three positions alive rather than replacing each with the next, and modern institutions contain elements of all of them without saying so. That matters practically. A minister who funds a levee and a community organisation that funds tenure reform are not disagreeing about facts; they are standing at different points on that historical line. Being able to say which paradigm an intervention assumes, what it therefore makes visible and what it hides, is the analytical skill this week is for. It is also the reason the field is now explicitly interdisciplinary: the early twentieth century tried a purely physical account, spending rose, understanding improved, and losses kept climbing anyway. Chapter 02 · Frameworks for vulnerability and resilience

What is the difference between weather and climate, put precisely?

Weather is the current state of the atmosphere over minutes to months. Climate is a statistical description of atmospheric conditions averaged over a specified period. The distinction is not about duration alone, it is about the kind of object: weather is a state and climate is a distribution. That has two consequences the unit cares about. First, a single hot day says nothing about climate, and a shift in the distribution says nothing about tomorrow, so arguments that use one to settle the other are category errors in both directions. Second, every climate statement carries a hidden baseline, because an average is always an average over something. A warming figure quoted without the period it is measured against and the window it is averaged over is not comparable to any other warming figure, and stripping the baseline is the fastest way to write a sentence that is not quite true. Chapter 03 · Weather, climate change and how the climate is measured

Why is drought not just low rainfall?

Because the definition is relative in two directions at once. It is relative to the local baseline, which is why an arid region receiving its usual very small rainfall is not in drought, and it is relative to demand, which is why two places with identical deficits can be in and out of drought depending on what they need water for. That double relativity also makes droughts genuinely hard to compare, since they differ in geographic extent, location, seasonality and the duration of the deficit. It is the reason Australia bands deficiency by percentile rather than by millimetres: serious deficiency at rainfall in the lowest 5 to 10 percent of historical totals for that place and period, and severe at the lowest 5 percent. A national map built on absolute amounts would be meaningless across a continent this varied. Chapter 04 · Droughts and floods in a changing climate

Why is defining a heatwave so difficult, and why does it matter?

It matters because the definition decides whether a warning is issued, and heat is the deadliest natural hazard in Australia since 1900. It is difficult because every simple definition fails in a predictable way. A fixed temperature threshold cannot travel between places, because 35 degrees means something different in two cities with different climates. A threshold relative to the average maximum handles that but still ignores humidity, still ignores night-time temperature, and still sits on a baseline that is itself moving as the climate warms. And any summer-only definition misses unseasonable events in spring, which are disproportionately deadly precisely because nobody is acclimatised. The unit's answer is a definition that is relative rather than arbitrary and that reports several characteristics rather than one number: frequency, duration, magnitude, spatial extent and timing. Chapter 05 · Heatwaves and bushfires in a warming climate

How do I tell a tornado from the things that look like one?

Use structure rather than strength, because a strong gustnado can do more damage than a weak tornado and the classification is not about damage. Two tests settle it. Is the vortex attached to a convective cloud above? A gustnado is not, which is why it fails the definition despite looking convincing. Is it in contact with the ground? A funnel cloud is not, so it produces no debris and no damage. A dust devil fails a third test, since it forms on a dry hot clear day with no cloud at all and is driven by surface heating rather than by a storm. A waterspout passes every test and is simply a tornado over water. Answering with these tests rather than with wind speeds is what an examiner is looking for. Chapter 06 · Tornadoes and tropical cyclones

What is the difference between magnitude and intensity?

Magnitude is quantitative and describes the earthquake; intensity is a qualitative reading of one place. One earthquake has one magnitude and as many intensities as there are locations to observe it. Magnitude is reported on the Richter scale historically, defined as the logarithm of the maximum wave amplitude on a standard instrument at a reference distance, and on moment magnitude since the 1970s, which calculates energy from the seismic moment. Intensity is reported on the Modified Mercalli scale, twelve levels in roman numerals, with the lower levels built from how people responded and the upper levels from observed structural damage. It is explicitly a subjective measure, and that is a feature rather than a defect: it records what was experienced where people actually were. A complete description of an event gives magnitude, depth and the intensity distribution. Chapter 07 · Earthquakes and how they are measured

Why do volcanoes occur where they do?

In three settings, and the settings explain most of what a volcano will do. At an oceanic spreading ridge, plates diverge and new crust forms, producing generally fluid eruptions. Above a subducting plate, magma generated at a depth of around one hundred kilometres rises to intrude the crust or erupt explosively, producing arcs of volcanoes aligned parallel to the trench, and these are the systems that produce the most dangerous eruptions. Over a hot spot, a persistent mantle plume produces volcanism independent of any boundary, and because the plate moves over the fixed plume the result is an age-progressive chain of islands whose spatial sequence is also a temporal one. Being able to place a volcano in one of the three settings gives you a first estimate of its eruption style before you know anything else about it. Chapter 08 · Volcanic eruptions and their hazards

Why is a big earthquake not enough to produce a tsunami?

Because a tsunami requires the sudden vertical displacement of a large volume of water, and not all large earthquakes displace water vertically. Thrust faulting on a subduction interface lifts the seafloor and moves the entire water column above it, which is why the unit's magnitude 9.0 offshore example produced run-up reaching about 40.5 metres. Strike-slip faulting moves the ground horizontally past itself, so even a shallow magnitude 7.0 close to a coast can produce liquefaction, landslides and no tsunami at all, which is exactly what the unit's second example did. Three questions therefore replace magnitude when you are asked about tsunami risk: was the rupture beneath water, was the faulting vertical in character, and how much seafloor area was displaced, which is where magnitude finally enters as a proxy for rupture area. Chapter 09 · Tsunamis and mass movement

Why does a geoscience unit finish with space?

Because the classification demands it. Week 2 divided the energy that drives Earth processes into endogenic sources from inside the planet and exogenic sources from the Sun and other astronomical bodies, and named exogenous hazards, external to the Earth, as a category with solar flares and asteroids as its examples. The vulnerability frameworks used in the unit likewise treat astronomical hazards as a distinct hazard class alongside geological, hydrological and biological ones, and the unit's own introduction describes asteroid impacts and solar storms as megahazards. Reading set with the unit goes further and treats extraterrestrial impact as one of the primary energy sources of disaster, on a par with the internal heat that drives plate tectonics. So the week is not an afterthought; it closes a classification that was opened in Week 2. Chapter 10 · Space hazards and planetary defence

How much GIS does the unit expect, and do I need experience first?

A good deal, and no. The practicals use open-access software and teach it from the beginning: the first week has no practical class but provides pre-recorded material on basic GIS concepts, and the following weeks build a map from scratch and use it to explore exposure and vulnerability to coastal hazards. That work becomes the group presentation. From the seventh week the practicals become a seven-part multi-hazard mapping exercise, and that becomes the individual assignment. Between them the two artefacts are 40 percent of the unit mark. What is being assessed is not software fluency for its own sake but spatial reasoning: choosing layers that answer a hazard question, handling elevation data honestly, and producing a map a non-specialist can read and act on. Chapter 11 · Mapping hazard and risk with GIS

What does a geoscientist actually do about hazards?

Four things, in a sequence that the unit names as its core-concept vocabulary for this week: detect, monitor, forecast and warn, supported by observation and measurement, real-time systems, spatial technologies, and communication. Laid out as a chain, with understanding and acting added at the end, it becomes a diagnostic tool rather than a job description. A disaster post-mortem is almost always a question of which link failed, and the pattern across every case study in this unit is consistent: investment concentrates on the first three links, where the science is, and almost all documented failures occur in the last three, where the people are. That is why Module 3 spends as much time on data criticism and communication as on capability, and why an answer about improving hazard management should say which link it is repairing. Chapter 12 · Detecting and monitoring hazards for risk reduction

What made one Australian fire season different from the others?

A chain of enabling conditions across five timescales rather than a single cause. A multi-year drought repeatedly diverted moisture away from the south-east, leaving fuels cured across an enormous area, and it culminated in an extreme positive Indian Ocean Dipole. The following year was the warmest and driest on record nationally, with the national rainfall total reported in the unit as 37 millimetres, or about 11.7 percent, below the previous driest year's 314.5 millimetres. Extreme fire weather then combined temperature, humidity and wind at the top of the danger index, cold fronts drove the wind changes that convert a narrow head fire into a wide one, and at the bottom of the chain fires generated their own thunderstorms, with 44 pyrocumulonimbus events in that single season. The important structural point is that mitigation acts on the top of the chain and everything below it is response. Chapter 13 · Bushfire case studies in the Australian context

How to study for the exam

Treat GEOS2111 as two units running in parallel and plan for both. The concept and hazard stream is assessed by the early feedback test and the exam, and rewards a small, disciplined set of notes built weekly. The GIS stream is assessed by the group presentation and the individual assignment, together 40 percent, and rewards work in the practical class rather than after it.

For the concept stream, build one page per hazard from Week 3 onward and never let it grow past a page: mechanism in a sentence, the measurement scale and what it truly measures, the secondary hazards that follow, one named case with country and date, and one management response.

Ten of those pages are the whole of Module 2. For Weeks 1 and 2, keep instead a single sheet of definitions with the frameworks drawn as diagrams, because the conceptual vocabulary is what the later weeks are graded against and it is what the early feedback test checks.

For the GIS stream, finish each practical inside the class or the same day, save the project file with its layers intact, and write two lines about what the map showed while you still remember; the individual assignment is assembled from seven practical parts and reconstructing part three in Week 11 is miserable. Two habits do disproportionate work.

First, whenever the teaching gives you a physical process, immediately ask who is exposed and which pre existing conditions turn that process into losses, because the unit's learning outcomes are written in exactly that shape. Second, keep a running case study table with a deliberate spread of high, middle and low income countries, since one outcome asks for that range and it cannot be manufactured in the revision week.

Going into the exam, remember it is only 90 minutes across ten hazard families, so rehearse fast, structured recall rather than long form essays.

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