Teachers’ notes | Collect data
Learning objectives:
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To understand the importance of Antarctic data and its links to the Earth System as a whole
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To understand the complexities involved in collecting Antarctic data
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To use the data provided to create graphs/charts/maps and improve data analysis skills
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To be able to draw conclusions from the data trends and compare different results
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To review and understand data relating to climate change and draw one’s own conclusions
Prepare to go south
This activity shows the user just how much is involved in getting out into the field in Antarctica to collect data. It is designed to highlight what a remote and difficult place Antarctica is to get to and work in – and just how far away it is from the UK. It should be emphasised that despite these challenges, the UK sends hundreds of people there every year because science in Antarctica is very important to help understand what is happening all over the world.
Collect data about the Ocean / Collect data about the Air / Collect data about the land
These video-diary-style activities lead the user through the data collection process and are designed to immerse the viewer in the location – to feel like you are travelling out into the Antarctic wilderness to collect your data.
Once the data is available, there are suggestions on how to process and analyse graphs and charts and also to compare results and draw conclusions. This can be led by the teacher depending on the statistical abilities and required outcomes for the class.
Using your data
When the data has been analysed, a discussion into what the data is telling you should be led by the teacher.
Answers to the example questions:
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How can the sea temperature be less than 0°C without it freezing?
The ocean around Antarctica is often less than 0°C. This is due to its salt-content, as salty sea-water has a higher density and lower freezing point than fresh water.
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Air temperature seems to get colder with height, then warmer, then colder again. Why?
The atmosphere is split into layers where different physical effects dominate. In the lowest layer (the troposphere – up to ~10km), temperatures decrease with height as the atmosphere is well mixed, and as a parcel of air moves up, it expands and therefore cools. The stratosphere (up to ~50km) then increases in temperature with height due to absorption of solar UV radiation by ozone at these altitudes. Above that, the mesosphere decreases in temperature again up to ~90km.
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Are the three geological areas studied all the same? If not, why do you think they are different rock types and ages?
The areas have different rock types and ages. This is because these three areas came from different parts of the Gondwana supercontinent and collided to form the current landscape.
Other possible questions/answers:
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Sea temperature seems to get colder, then stabilise with depth. Why?
Deeper layers of the ocean are not mixed like the upper layers, and are therefore much more thermally stable. The turbulent upper layers transfer heat upwards to the atmosphere and downwards to the deeper waters.
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Why do you think that sea water pH is lowest (most acidic) just below the surface?
There is often a layer of algae just below the surface that causes the water to become slightly more acidic.
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How do icebergs affect organisms on the sea bed? How does this change with depth?
In shallow waters, iceberg scour damage occurs much more frequently that at greater depths, however, deeper scours are proportionally more devastating due to the massive size of the icebergs involved.
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Does air pressure decrease uniformly as you get higher?
Air pressure decreases exponentially with height all the way up through the atmosphere.
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Why are the striking angles of the rocks different?
The directions of strike are often related to the angles of collision of the different land masses. This reflects the overall complexity in understanding Antarctica’s geological past.
Graphs showing changes in air and sea-surface temperature for the Antarctic Peninsula over the last 50 years
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What conclusions can you draw from the results?
The trends show a clear increase in air (3°C) and sea-surface temperatures in the Antarctic Peninsula region.
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What might be causing the changes?
Increased greenhouse gases in the atmosphere and climate change are significant contributors.
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How does the sea-temperature change differ at various depths?
Studying the charts reveals the different rates of warming/cooling at different depths. Students should be encouraged to analyse and understand the data to reveal that the greatest warming is at the surface, compared to 100m depth. This can then be linked to climate change and also the air temperature data.
Graphs showing carbon dioxide (CO2) concentration in the Earth’s atmosphere and global temperature over the last 800,000 years
The fluctuating graph reflects ice-ages and interglacials (as we are in now) over the last 800,000 years. The link between temperature (red) and carbon dioxide (black) should be highlighted. The overall CO2 maximum should also be noted (~300ppm).
Graph of carbon dioxide concentration from 800,000 years ago to the present, highlighting the last 25 years
This clearly shows a dramatic increase in carbon dioxide levels in recent times, with the current CO2 maximum higher than at any time over the last 800,000 years. The steepness of the graph over the last 150 years should also be highlighted. This is caused by human activity and a discussion about future change and predictions for the future can be had, referring back to the links with temperature and predictions for the future/climate change.
Graph showing ozone concentration over Halley Research Station between 1956 and 2008
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Does the ozone data prove that mankind can affect the global atmosphere?
The rapid decrease in atmospheric ozone over the Antarctic was caused by the release of chlorofluorocarbons (CFCs), mostly in the northern hemisphere. The ozone ‘hole’ formed in less than a decade. This was the first proof that humans can influence the atmosphere around the entire planet in a comparatively short time.
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Does it also show that international co-operation can change things for the better following the 1987 Montreal Protocol to ban the use of CFCs that caused the Ozone Hole?
The graph shows that the decline has levelled off. This is a direct result of the 1987 Montreal Protocol and proves that international action can reverse dangerous climate trends. The ozone hole should repair itself in ~60 years. A discussion can be had linking this theory to climate change and the effectiveness of current environmental initiatives/Government action around the world.