Grade 10 June Flashcards
What is the atmosphere?
The thin layer of gases surrounding the Earth, kept in place by the Earth’s gravity.
What is oxygen?
A gas with no colour or smell that is very important for life on Earth.
What are constant gases?
Those atmospheric gases whose concentrations are stable and do not change much over time.
What are inert (noble) gases?
Colourless, odourless gases with low chemical activity.
What is water vapour?
The gaseous form of water.
What is atmospheric pressure?
The pressure caused by the weight of the air above any area of the Earth’s atmosphere.
What is ozone?
A molecule made up of 3 oxygen atoms instead of the usual 2. It absorbs ultraviolet radiation.
What is the ozone layer?
A layer in the stratosphere with a high concentration of ozone. It protects life on Earth by absorbing ultraviolet radiation from the sun.
What is the ozone hole?
The decrease in stratospheric ozone quantities, observed on a seasonal basis (September to November) over Antarctica, and to a lesser extent over the Arctic.
What is the first 80km called?
Homosphere
Give an example of an inert/ noble gas.
Argon
What are the 5 important qualities of the atmosphere?
Contains the air we breathe
Absorb’s the Sun’s radiation
Burns up meteoroids before they hit the earth
Keeps moderate heat on earth
Traps heat at night
What is the first 80km of the atmosphere called?
The homosphere
What is 80-100km of the atmosphere called?
The turbopause
What is the section of the atmosphere that’s 100km and up called?
The heterosphere
What is the border between stratosphere and the mesosphere?
The stratopause
In which two layers of the atmosphere does temperature decrease with altitude?
The troposphere and the mesosphere
Where is the homosphere?
0-80km
Where is the heterosphere?
100km and higher
What do you call the border between the mesosphere and the thermosphere?
The mesosphere
Where is the thermosphere?
80-480km
Where is the turbopause?
80km-100km
In which 2 layers of the atmosphere does temperature increase with altitude?
In the stratosphere and the thermosphere
Where is the troposphere?
Up to about 12km
Where is the stratosphere?
12-50km
Where is the mesosphere?
50-80km
Where is the ozone layer?
15-35km
What man made things can be found in the stratosphere?
Aeroplanes and weather balloons
What does the ozone layer do?
Absorbs ultraviolet radiation
Where are the strongest winds found?
Up to 3000km/h
In the mesosphere
What was discovered in 1913 by a French physicist?
The ozone layer
How do UV rays affect people?
Non-melanoma skin cancer
Melanoma
Cataracts
How do UV rays affect plants?
Ways plants form
Affect soil nutrients
Growth
Affects their metabolisms
Reduces photosynthesis
How do UV rays affect animals
They feed on affected plants
How are marine animals affected by UV rays?
They eat phytoplankton, which grow close to the surface and become affected
What was done to reduce CFC’s in 1987?
The Montreal protocol
What is insolation?
Incoming solar radiation
What is convection
A process in which heat energy is distributed through movement of heat molecules from one position to another.
What are greenhouse gases?
Gases that absorb radiation from the Earth and contribute to the warming of the Earth’s atmosphere
What is global warming?
The process in which the world’s temperature is rising
What is a temperature range?
The difference between minimum and maximum temperatures
What are isotherms?
Lines on a map joining places with the same air temperature.
How much of the Sun’s rays are absorbed by the Earth’s surface?
46%
What is another term for the transfer of energy from the earth’s surface?
Terrestrial radiation
What happens after the sun’s rays reach the ground?
The short-wave rays are changed to long-wave(infrared) waves. These are radiated back into the atmosphere
What is convection?
The vertical transfer of energy by movement of molecules.
What is conduction?
The transfer of energy from molecule to molecule.
What 3 currents are on the coast of South Africa?
Cold Benguela current
Warm Agulhas current
Warm Mozambique current
In what 2 ways are places further from the equator cooler?
Solar radiation must travel through a thicker layer of atmosphere
Solar radiation is distributed over a greater surface
What climates do coastal and inland places have?
Coastal climates: maritime climate
Inland climates: continental climate
What are the 6 factors that influence horizontal temperature change?
Latitude Altitude Distance from the sea Ocean current Aspect Movement of air masses
Climate graph excluded.
Include if needed in November exams
What are 6 greenhouse gases?
Carbon dioxide Methane CFC's Nitrous oxide Water vapour HFC's
What does it mean to annotate?
To add explanatory notes to a diagram or sketch.
What does it mean to classify?
To arrange or organise information into groups based on similarities.
Note!
Study precipitation symbols
What is a synoptic chart?
A summary of the weather of an area based on information.
From where can we get weather information?
Name at least 4
Weather balloons, satellites, weather stations, aeroplanes, ships, weather buoys and islands with weather stations.
Who organises the weather information onto synoptic charts and how often?
The South African Weather Services every 6 hours.
Who are meteorologists?
Specialists that study the processes in the atmosphere that cause weather.
How do you describe the weather conditions shown at a weather station?
Air temperature Dew point temperature Cloud cover Wind direction Wind speed Precipitation
What is a glacier?
A mass of accumulated snow and ice moving down a slope from high ground.
What is evaporation?
The process in which liquid water becomes water vapour.
What is sublimation?
The process in which a solid changes directly into a gas.
What is condensation?
The process in which water vapour turns into liquid water.
What is ground water?
Water located underground in soil spaces and in cracks of rock.
What is transpiration?
The process in which plants give off water.
What is evapotranspiration?
The total amount of moisture removed by evaporation and transpiration from the surfaces and vegetation.
What is precipitation?
Rain, hail, snow and other forms of water falling from the atmosphere.
What is infiltration?
The process in which water on the ground enters the soil.
What is run-off?
Water that flows over the land when the ground cannot absorb any more water.
What is a saturation point?
The point at which no more water can be absorbed.
What is erosion?
The process in which rock that has already broken down by weathering is removed from an area, often by water, wind or ice.
What is humidity?
Water vapour in the air.
What is relative humidity?
The percentage of water vapour in the air relative to the amount of water vapour that would be present in the air if the air were saturated at the same temperature.
What is a condensation level?
The height at which the relative humidity of rising air reaches 100%, it is where clouds form. P
What are condensation nuclei?
Microscopic particles such as dust or pollution around which raindrops form.
What is dew?
Water that condenses out of the air and appears on cold objects such as vegetation in the cooler mornings and evenings.
What is a dew point?
The temperature at which air can no longer hold all its water vapour and condensation begins.
What is frost?
The frozen deposition of water vapour from saturated air.
What is hail?
Precipitation in the form of pieces of ice.
What is a rain shadow?
A drier area that lies on the leeward (or downward) side of an object.
What is snow?
Precipitation in the form of small crystals of ice called snowflakes.
What is convection?
A process in which heat energy is distributed by the movement of heated particles from one position to another.
What is the proper name for the water cycle?
The hydrologic cycle
What do you say if the air can’t hold more water vapour?
The air is saturated.
What 2 types of thermometers do you get?
Dry-bulb thermometer
Wet-bulb thermometer
What do the two types of thermometers measure?
Dry-bulb thermometer measures air temperature.
Wet-bulb thermometer measures humidity.
What is aspect?
The average weather conditions of an area usually measured over 30 years.
What is convectional rainfalls?
Rain caused when the sun heats the ground, the ground heats the air, which then rises to form clouds.
What is cyclonic/ frontal rain?
Rain caused when a warm front meets a cold front
What is relief rain?
Rain that occurs when air is forced to rise over a hill or mountain.
Note!
Look at types of clouds.
🌤 ☁️ ⛈ 🌨
☔️
👫 🌴 🌲 🚴🏼 💂🏼 ⛄️
What instrument is used to measure air pressure?
Barometer
What instrument is used to measure cloud cover?
Your eyes. Satellite images
What instrument is used to measure precipitation?
Rain gauge
What instrument is used to measure visibility?
Visibility meter
What is visibility?
How far ahead we can see.
E.g. On a foggy day.
What instrument is used to measure wind direction?
Weather vane
What instrument is used to measure wind speed?
Anemometer
Note!
Study map work!
What is magma?
Molten material that forms deep beneath the earth’s surface.
What is lava?
Magma that reaches the surface.
What is weathering?
A process in which rocks are broken down by water, air and living things.
What is sediment?
Weathered pieces of earth sediment.
What are rocks?
Any solid mass of mineral or mineral-like matter occurring naturally as part of our planet.
What are the 3 Rock types?
Igneous rock
Sedimentary rock
Metamorphic rock
How is igneous rock formed?
By the crystallisation of molten magma.
How is sedimentary rock formed?
From the weathered products of pre-existing rocks that have been transported, deposited, compacted and sedimented.
How is metamorphic rock formed?
By the alteration of pre-existing rock deep within the earth (but still in the solid state) by heat, pressure and/ or chemically active fluids.
Name 4 examples of sedimentary rock.
Conglomerate (pebbles and sand stuck together)
Shale
Limestone
Sandstone
Name 3 examples of igneous rock.
Granite (large crystals, cooled magma)
Obsidian (cools quickly)
Basalt (hard and black, cooled lava)
Name 3 examples of metamorphic rock.
Gneiss (changed granite)
Marble (changed limestone and dolomite)
Slate (changed shale)
How is a sill formed?
Magma pushes between rock layers horizontally.
What is a pluton?
A large rock formation. Smaller than a batholith.
What is a batholith?
The largest rock formation. Usually granite.
How does a laccolith form?
Magma intrudes horizontally and pushes top layers of rock upwards.
How does a dike form?
Magma pushes into cracks vertically.
What is another name for a dike?
A dollente
How does a lopolith form?
Magma intrudes the layers horizontally. Rock underneath sinks down under the weight of the magma. Exposed as a depression.
What are the 4 types of plate boundaries?
Destructive margins
Collision margins
Constructive margins
Conservative margins
What happens at destructive margins?
Oceanic crust moves towards continental crust. Oceanic crust is forced downwards.
What happens at collision margins?
Two plates consisting of continental crust move together. Rocks between plates are pushed upwards to form fold mountains.
What happens at constructive margins?
Two plates move away from one another. Molten rock rises to fill the space. New oceanic crust and mid-ocean ridges formed.
What happens at conservative margins?
Two plates slide slowly past each other sideways. No crust is formed or destroyed.
When plates push together and sedimentary rock folds, what does one call the individual folds, the top of the folds, the bottom of the folds and the cracks where rock is stretched?
Individual fold: limb
Top of a fold: anticline
Bottom of a fold: syncline
Cracks in rock from stretching: joints
What is a monocline?
Not important for June exams
An area of steeply sloping rock strata in an area of horizontal/ gently sloping rock strata.
What is a horst/ block mountain?
A block of land uplifted between parallel faults.
What is a gravin/ Rift Valley?
A block of land which slips down between parallel faults.
What is the range of the Richter scale?
0-9 and over
What do earthquakes travel in the form of?
Seismic waves
What are the names of the point within the earth where an earthquake starts and the point on the surface above where the earthquake starts.
Within earth: fokus
On surface: epicentre
What are the 3 types of seismic waves and what do the do?
Primary waves: squeeze and stretch the ground.
Secondary waves: move ground up and down and side to side.
Surface waves: move ground in circular motion.
What is volcanism?
Process where magma from the mantle moves to the earth’s surface as lava.
What are the 2 types of volcanism and how do they differ?
Intrusive volcanism: magma solidifies in crust.
Extrusive volcanism: magma erupts onto surface.
What is a vent?
The pipe of a volcano.
What are the 5 types of volcanoes?
Shield volcano Dome volcano Cinder cone Composite volcano Caldera volcano
What is a shield volcano?
Successive layers of fluid lava. No explosive activity.
What is a dome volcano?
Successive layers of viscous lava-lava does not flow far.
What is a cinder cone?
Successive layers of ash and cinders. Not much lava. Explosive activity.
What is a composite volcano?
Layers of lava and pyroclastic material. Explosive volcano.
What are the 3 types of faults?
Normal fault, reverse fault, transform or tear fault
What is the cause of a normal fault and a reverse fault?
Normal fault: tension
Reverse fault: compression
