Measurements and monitoring in Antarctica
This interactive provides a brief look at some of the measurements and monitoring that happen in Antarctica. Some of the monitoring techniques are high tech and others involve a bit of bravery and fun. Pictured is a scientist collecting seal urine.
Click on the labels for text and media about how and why scientists make measurements and monitor the land, seas and skies.
Select here to view the full transcript and copyright information.
Since 1957, Aotearoa New Zealand has sponsored research programmes in Antarctica. Teams of scientists have measured the land, the sea and the atmosphere – establishing new datasets and maintaining long-running ones. This interactive provides a snapshot of high-tech and low-tech monitoring that happens in and around Scott Base and the Ross Sea.
The image shows a scientist collecting seal urine – just one method of measurement and monitoring!
Transcript
Monitoring ozone since 1958
Arrival Heights, located northwest of Scott Base, is an Antarctic Specially Protected Area. The location is a natural and electromagnetically quiet site – making it ideal for upper atmospheric research. New Zealand began collecting data there in 1958.
The lab has a variety of sensitive instruments, including a Dobson ozone spectrophotometer that was built in 1937! When first built, it was fully mechanical, but it’s been upgraded to some extent. Its computer runs on DOS and has a floppy disk drive. The Dobson is one of the earliest instruments created to measure atmospheric ozone. Data from this technology aided the discovery of the hole in the ozone layer.
The Arrival Heights lab is also equipped with modern spectrometers.
As a protected area, visitors need a permit to visit. Great care is taken to maintain the electromagnetic quietness of the site. Vehicles are not allowed to use their headlights when approaching the lab, and people moving between buildings in the polar night navigate using a rope.
Alec Dempster is a science technician with Antarctica New Zealand. He tells us about the Dobson ozone spectrophotometer.
Questions for discussion
What do you think Alec means when he tells us the Dobson ozone spectrophotometer was fully mechanical when first built?
How does this help the machine’s longevity?
Select here to view video transcript, questions for discussion and copyright information.
Detecting crevasses in Antarctica
Travel in Antarctica can be slow and dangerous. Glacial land ice is always moving, and this stress causes the ice to crack. Sea ice is also dynamic and under stress. The stress causes crevasses – holes and deep cracks in the ice.
Crevasses have been an issue for humans from the early days of dog sleds and tractors – even for today’s PistenBully and Hägglund vehicles. Technology has helped to make the trip safer, but not always faster.
Remote sensing radar from satellites is often the first step to mapping a journey. It can spot cracks that are not visible due to snow cover.
Journeys to remote field sites also use ground-penetrating radar – fixed on a gantry fitted to the front of the PistenBully. The gantry is 20 m long, so travel is slow and careful observation is a must!
Antarctica does have ice roads – for example, the South Pole Traverse is a 1,500 km route across the Ross Ice Shelf to the South Pole. Ice roads are constructed by levelling snow and filling in and/or avoiding crevasses and other dangers. The roads are not paved, so they are marked with flags to aid navigation.
There are shorter roads that link Scott Base with the local airfields and the United States McMurdo Station.
Professor Dave Prior, from the University of Otago, tells us what makes crevasses so dangerous and how radar helps to identify their locations.
Jargon alert
POB – people on board.
Questions for discussion
What makes crevasses so dangerous?
What do crevasses look like in the radar images?
Why do you think the vehicles in the tractor train are so spread out when travelling?
Select here to view video transcript, jargon alert, questions for discussion and copyright information.
Measuring cold weather with a t-shirt
Antarctica is cold! The coldest temperature ever recorded at Scott Base was -57.0°C on 25 September 1968. The warmest was 6.8°C on 8 January 1970.
When the temperatures are low and the southerly windspeeds are high, it helps to have a sense of humour. As well as weather station data, there are other ways to demonstrate just how cold it can get, even during the summer season!
For example, a wet T-shirt and a hardy individual is one way to demonstrate the harshness of the Antarctic climate!
Questions for discussion
Why do you think the T-shirt freezes but the person holding it seems to be OK?
How do we know the T-shirt is actually frozen and not just a stunt?
If you were in Antarctica, would you do this demonstration?
How cold does it get in Antarctica?
Select here to view video transcript, questions for discussion and copyright information.
Antarctic weather measurements and monitoring
People who work in Antarctica need to know about the weather for flights and other forms of travel, planning and operating field sites and for overall safety.
Knowing about Antarctic weather is also important for non-residents. Although it’s a long way away, Antarctica and the rest of the world are globally connected via atmospheric circulation and ocean currents.
Global weather models require observational data from Antarctica to make accurate forecasts. This is especially important for locations nearest to Antarctica – Aotearoa, Australia and southern parts of Africa and South America.
The data is also used to calibrate and validate measurements made by satellites. Many of these measurements inform our understanding of climate change and sea-level rise.
Professor Adrian McDonald, University of Canterbury, uses on-site weather stations in Antarctica to calibrate and validate satellite measurements.
Jargon alerts
Validate means to confirm or verify something.
Calibrate means to check or standardise a measuring device.
Questions for discussion
Why is it important to have more than one method to measure the weather?
Why are the weather stations placed along the satellite tracks?
Select here to view video transcript, jargon alerts, questions for discussion and copyright information.
Antarctic species monitoring – macro and micro
When we think about the Antarctic, penguins, seals and whales are the species we often associate with the icy marine and terrestrial ecosystems.
Adélie penguins are recognised as a sentinel species – an organism that is monitored to provide early warning of potential health or environmental harm. Other sentinel species are much smaller and possibly less eye-catching – such as terrestrial mosses and cyanobacteria.
New Zealand scientists monitor species of all sizes to collect baseline and longitudinal data about their distribution, interactions and habitats and to make predictions about responses to future local and global changes.
Monitoring includes a myriad of techniques and lots of technology:
Census counts of large species like seals and penguins using high-resolution images from helicopters and satellites – including citizen science projects.
Environmental DNA (eDNA) along with collecting samples of penguin guano and seal urine and scat to study Ross Sea food webs.
Collecting seal scat to test whether nearby construction activities are causing stress.
Underwater cameras and hydrophones to watch and listen to animal behaviour under the sea ice.
Specially engineered drilling equipment to capture fragile layers of platelet sea ice along with the water and living things within the layers.
Drones equipped with multispectral and hyperspectral sensors to detect terrestrial vegetation. Both types of sensors use image layers/wavelengths across the electromagnetic spectrum and can see things that human eyes cannot.
Using PCR to find and identify extremophilic microorganisms that live in the harsh McMurdo Dry Valleys.
Anthony Powell works with Antarctica New Zealand. In this video, he sets up a hydrophone, which he lowers through a hole in the ice, to listen to how seals communicate while underwater.
Questions for discussion
Why do scientists spend time observing animal species?
Why is this important?
What do you think they might learn by listening to the seals’ vocalisations?
Select here to view video transcript, questions for discussion and copyright information.
Drilling sea ice cores
Ice cores are cylinders of ice that come from ice sheets, glaciers or sea ice. They are frozen archives that give us snapshots of the past and the present.
Air bubbles – gases trapped in ice – provide information about what Earth’s climate was like over hundreds of thousands of years. Other things in the ice like salt, dust or ash provide information and timelines about wind patterns or volcanic activity over time.
Sea ice cores provide information about ice structure, salinity and growth rates. Platelet ice layers also provide information about unique cold-water habitats for algae, bacteria and other tiny organisms – the base of the Antarctic food web.
Some of the ice samples are studied on site in Antarctica, but many are carefully packaged and shipped to Aotearoa New Zealand where they are stored in purpose-built laboratories.
Associate Professor Inga Smith from the University of Otago provides a brief introduction to how and why her team collects sea ice cores.
Point of interest
The scientists are using a pencil to make notes about their field work. They cannot use pens as the ink freezes in the cold weather!
Questions for discussion
Why are the scientists ‘digging out’ first?
What do you see/observe happening in the video? For example, what equipment are they using?
Why do you think the ice cores are sent to New Zealand for study?
Why would the scientists need a backup core?
Select here to view video transcript, point of interest, questions for discussion and copyright information.
Monitoring for nuclear explosions
The Comprehensive Nuclear-Test-Ban Treaty bans all nuclear test explosions, whether for military or civilian purposes. The International Monitoring System is a global network hosted by 89 countries and Antarctica. It uses four types of verification: seismic (underground shock waves), hydroacoustic (underwater sound waves), infrasound (atmospheric sound waves) and radionuclide (radioactive particles or gases) to monitor for nuclear explosions.
There are seven monitoring stations in Antarctica. New Zealand has six monitoring stations and a radionuclide lab.
Professor Dave Prior is with the University of Otago Department of Geology. Dave tells us about the infrastructure near a research site at Windless Bight. Nearby is one of the nuclear monitoring stations.
Questions for discussion
Why is the route between Scott Base and the Comprehensive Nuclear-Test-Ban Treaty (CTBT) site clearly marked on the map?
If nuclear test explosions are banned, why do we need monitoring stations around the globe?
Select here to view video transcript, questions for discussion and copyright information.
Measuring land and sea ice thickness
Land ice is freshwater ice that covers the land area of Antarctica. Sea ice is frozen seawater. Every winter, Antarctica doubles in area because of an increase in sea ice!
Measuring the thickness of land and sea ice and how quickly these thicknesses change allows scientists to make more accurate predictions about future changes in Antarctica. The data is also used to inform climate models.
There’s a lot of ice in Antarctica. The average thickness of land ice – the Antarctic ice sheet – is 2.16 km. That’s very deep – too deep to drill – so scientists use satellites instead.
Measuring the thickness of sea ice is more complicated as salt interferes with the radar waves. University of Canterbury’s Professor Wolfgang Rack explains how his team uses electromagnetic induction to overcome this issue.
Questions for discussion
Why do you think the EM bird needs to be as close to the sea ice as possible?
Why do you think the scientists use a helicopter instead of a PistenBully or other form of land transport?
Select here to view video transcript, questions for discussion and copyright information.
Acknowledgement
This resource was produced with the help of educators Carol Brieseman and Dianne Christenson. Carol and Dianne travelled to Antarctica as part of Antarctica New Zealand’s Community Engagement Programme.
