To examine the effects of natural emergency events, students need to have some understanding of how those events occur — and why. The following scientific investigations will help build these understandings.
Our Earth is not a solid rock but is made up of a series of different layers called the crust, the mantle, the inner core and the outer core. The crust is the outside layer that we live on and is formed from a series of solid plates that float on the liquid mantle below.
The plates are constantly moving due to convection currents occurring in the mantle layer as this layer is liquid magma and heats up and cools down resulting in convection currents. Some of these plates move apart (such as the plates running down the middle of the Atlantic Ocean). Some plates move directly into each other, such as the collision of the Australian Plate with the Pacific Plate forming the Southern Alps in the South Island. Others form subduction zones, where one plate moves under the other. This occurs in New Zealand in the North Island, causing a line of volcanoes and geothermal areas. When plates move we get small cracks called fault lines. As fault lines move there can be either a gradual release of energy or a sudden release of energy resulting in earthquakes.
The Richter Scale measures the size of an earthquake. It is a measure of the energy released. When earthquakes are deep in the Earth their energy is the same but the shaking does not feel as strong as shallow earthquakes.
The amount of shaking you feel is another way to describe earthquakes. This is called the intensity. It is stronger when you are close to the earthquake source and when the earthquake is shallow, and decreases the further away you are. So we describe earthquakes by the energy released or their magnitude, and also how strong the shaking feels or the intensity.
Build a quake-safe structure or design a building that could withstand an earthquake or a volcanic eruption. Use materials such as playing cards, Lego, wooden blocks and collected items from the school garden.
Investigate to find the answers to these questions.
With our substantial number of waterways, there are many parts of Aotearoa that could potentially be affected by a flood. In fact, floods are the most common emergency event around the country.
The water cycle simplified is when water circulates from clouds to the soil to streams to rivers to the oceans and then returns to the clouds.
When a lot of rain falls, it can be too much for the soil to soak up and streams can fill up. When streams and rivers fill up faster than they can flow out to sea the water runs onto the adjoining low-lying land surfaces and causes a flood. Urban flooding can also occur when there is too much water for the storm water drains to clear.
Flood map: Water Level Elevation Map gives a map of a local area and allows the user to adjust imaginary floodwaters to show how much of the land could end up under sea level.
The crust of the Earth may be made from solid rock but it has also changed over millions of years to form soil. This process is always occurring. Soils come in many different varieties. Soils can be worn down or worn away by water, wind and human activities. This is called erosion.
Where soils have built up over time and a sudden event such as a heavy downpour, flood or earthquake occurs, then a large quantity of soil can move quickly resulting in a landslide. However, this also depends on the type of soil and how ’sticky’ the soil particles are. ‘Sticky’ soil particles have lots of friction, so they hold together better than ‘smooth’ soil particles, which slide easier. It also depends on factors such as tree roots, which help hold soil together, preventing landslides. Gravity can also play an important part, as the steeper the slope of the land the greater the effect of gravity.
Above the crust (the solid layer of the earth that we live on) is a layer of air that is essential to all living things, called the atmosphere. Our atmosphere can be divided into different layers. Closest to the ground is the troposphere, which is about 8–15 kilometres thick. This is the layer where most of our weather occurs as it is the most dense. The air in the atmosphere is always moving as it heats up and cools down, causing convection currents that we experience as wind. Clouds are also a visible sign of these convection currents. This means that the air becomes unstable and when unstable air meets lots of moisture there is the potential for thunderstorms to occur.
This is an experiment that students in years 4–8 should be able to do without teacher guidance. If possible, have the students record their observations using a digital device to take photos and annotate the photographs afterwards.
In this experiment, water is used to represent hot and cold air. Blue water represents the cold air mass and red water represents the warm and unstable air mass. The warm water (air) is forced to rise by approaching cold water (a front). This is where thunderstorms would form.
Tsunami form when there is an earthquake that causes a vertical shift in the bottom of the ocean. This causes displacement of the water, which causes a series of waves to form. The waves travel out from the source like ripples travelling across a pond after you drop a pebble in it. Tsunami waves can travel across entire oceans. Landslides can also cause tsunami.
To help students understand how damaging a tsunami can be, introduce the concept of shoaling. The process of shoaling helps to explain why tsunami waves get taller as they approach the shore — and the taller they are, the more damage can be caused.
Volcanoes are mostly found along the borders between plates in the Earth’s crust. The Earth’s plates move around because they are floating on top of a layer of liquid rock called magma. Magma forms the layer we call the mantle. This layer is under a lot of pressure, and if there is a gap in the plates the liquid rock can be forced out (just like when you shake a bottle of fizzy drink and then open it). When the magma is forced out above ground, it cools to form solid rock. This is called lava. Lava can flow in sheets to form layers of new rock, but it can also build up hills and mountains, which we call volcanoes.
All of New Zealand’s active volcanoes are on the North Island or in the sea near the North Island. Volcanoes can produce lava as well as ash, lahar and a range of different gases, some of which are extremely poisonous. The shape and size of a volcano depends on the materials in the magma, the force of the explosions and its age. Volcanoes can be extinct, dormant or active.
The most common volcanic hazard is ash. It is very scratchy because volcanic ash is made up of tiny pieces of sharp rock. When an eruption happens, ash can be carried hundreds of kilometres in the atmosphere by winds. During the volcanic eruption of Mt Ruapehu in 1996, a thin layer of ash covered farms, cars and buildings.
Make small volcanoes out of gelatine and show how pressure in a volcano causes the eruption of magma.
To make one small volcano, you will need:
These resources help to teach students about the science of earthquakes.
The Earthquake Commission (EQC) has developed resources to help students and teachers learn more about the science of earthquakes.
GNS Science has a video explaining basic tectonic plate movement.
Learn more about earthquakes through our In an emergency section and through What's the Plan Stan?.
Students can learn how to build an earthquake-proof structure.
These resources help to teach students about the science of floods.
A map of a local area allows the user to adjust floodwaters to show how much of the land could end up under sea level.
Science Kids has a factsheet for kids giving a factual overview of floods.
A New Zealand perspective on floods from Te Ara, the Encyclopedia of New Zealand.
AFP has a video explaining floods and the damage they can cause.
Learn more about floods through our In an emergency section and through What's the Plan Stan?.
These resources help to teach students about the science of landslides.
One Geology Kids, has a pages containing landslide information for students.
A New Zealand perspective on landslides from Te Ara, the Encyclopedia of New Zealand.
Watch this GNS Science video where geologist Simon Cox explains some of the processes and features of the Dart landslide, including some mysterious 'dust bubbles' at the base of a mud waterfall.
Visit EQC’s Fix. Fasten. Don't Forget. for more information on making your home safer.
Use one of the experiments shown in this video to look at different kinds of erosion and landslides.
This experiment from Scientific American uses physics to explain land movement.
Learn more about landslides through our In an emergency section and through What's the Plan Stan?.
These resources help to teach students about the science of storms.
Science Kids New Zealand has fact sheets for students about different aspects of storms.
MetService has real time satellite imagery and thunderstorm warnings to track the storm activity in your local area.
In this interactive game, students can build their own hurricane. As they do so, they’ll learn what kinds of wind conditions, latitude, and sea temperature are favourable for a hurricane to be born.
Learn more about storms through our In an emergency section and through What's the Plan Stan?.
These resources help to teach students about the science of tsunami.
Learn about shoaling and how it works.
A New Zealand perspective on tsunami from Te Ara, the Encyclopedia of New Zealand.
Watch this video from GNS Science explaining how tsunami are formed and the damage they can cause.
Use this activity to investigate the power of a tsunami. In this activity, students will build a table-top village and use it to visualize the relative height and effects of tsunami.
Learn more about tsunami through our In an emergency section and through What's the Plan Stan?.
These resources help to teach students about the science of volcanoes.
Visit GeoNet to view the volcano cameras and see current volcanic unrest in New Zealand.
A New Zealand perspective on volcanoes from Te Ara, the Encyclopedia of New Zealand.
Watch this video from the Science Learning Hub explaining rock cores.
This video explains how volcanoes are formed and erupt.
Auckland Museum has information about Auckland's volcanoes.
Learn more about volcanoes through our In an emergency section and through What's the Plan Stan?.