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Quantarctica: Mapping Antarctica has never been so easy!

Quantarctica: Mapping Antarctica has never been so easy!

One of the most time-consuming and stressful parts of any Antarctic research project is simply making a map. Whether it’s plotting your own data points, lines, or images; making the perfect “Figure 1” for your next paper, or replying to a collaborator who says “Just show me a map!,” it seems that quick and effective map-making is a skill that we take for granted. However, finding good map data and tools for Earth’s most sparsely-populated and poorly-mapped continent can be exhausting. The Quantarctica project aims to provide a package of pre-prepared scientific and geographic datasets, combined with easy-to-use mapping software for the entire Antarctic community. This post will introduce you to Quantarctica, but please note that the project is organizing a Quantarctica User Workshop at the 2017 EGU General Assembly (see below for more details).


[Credit: Quantarctica Project]

What is Quantarctica?

Quantarctica is a collection of Antarctic geographic datasets which works with the free, open-source mapping software QGIS. Thanks to this Geographic Information System package, it’s now easier than ever for anyone to create their own Antarctic maps – for any topic and at any spatial scale. Users can add and plot their own scientific data, browse satellite imagery, make professional-quality maps and figures, and much, much more. Read on to learn how researchers are using Quantarctica, and find out how to use it to start making your own (Qu-)Antarctic maps!

Project Origins

When you make a sandwich, you start with bread, not flour. So why would you start with ‘flour’ to do your science?” — Kenny Matsuoka, Norwegian Polar Institute

Deception Island isn’t so deceptive anymore, thanks to Quantarctica’s included basemap layers, customized layer styles, and easy-to-use cartography tools. [Credit: Quantarctica Project]

Necessity is the mother of invention, and people who work in Antarctica are nothing if not inventive. When Kenny Matsuoka found himself spending too much time and effort just locating other Antarctic datasets and struggling with an expired license key for his commercial Geographic Information System (GIS) software in the field, he decided that there had to be a better way – and that many of his Antarctic colleagues were probably facing the same problems. In 2010, he approached Anders Skoglund, a topographer at the Norwegian Polar Institute, and they decided to collaborate and combine some of the critical scientific and basemap data for Antarctica with the open-source, cross-platform (Windows, Mac, and Linux) mapping software QGIS. Quantarctica was born, and was quickly made public for the entire Antarctic community.

Since then, maps and figures made with Quantarctica have appeared in at least 25 peer-reviewed journal articles (that we can find!). We’ve identified hundreds of Quantarctica users, spread among every country participating in Antarctic research, with especially high usage in countries with smaller Antarctic programs. We’ve been actively incorporating even more datasets into the project, teaching user workshops at popular Antarctic conferences – such as EGU 2017 – and building educational materials on Antarctic mapping for anyone to use.

A great example of a Quantarctica-made figure published in a paper. Elevation, imagery , ice flow speeds, latitude/longitude graticules, custom text and drawing annotations… it’s all there and ready for you to use! [Credit: Figs 1 and 2 from Winter et al (2015)].

What data can I find in Quantarctica?

  • Continent-wide satellite imagery (Landsat, MODIS, RADARSAT)
  • Digital elevation models and/or contour lines of bed and ice-surface topography and seafloor bathymetry
  • Locations of all Antarctic research stations and every named location in Antarctica (the SCAR Composite Gazetteer of Antarctica)
  • Antarctic and sub-Antarctic coastlines and outlines for exposed rock, ice shelf, and subglacial lakes
  • Magnetic and gravity anomalies
  • Ice flow velocities, catchment areas, mass balance, and firn thickness grids
  • Ancient UFO crash sites

…just to name a few!

Four examples of included datasets. From left to right: Ice flow speed, drainage basins, and subglacial lakes; bed topography; geoid height; modeled snow accumulation and surface blue ice areas [Credit: Quantarctica Project]

All of these datasets have been converted, imported, projected to a standard Antarctic coordinate system, and hand-styled for maximum visibility and compatibility with other layers. All you have to do is select which layers you want to show! The entire data package is presented in a single QGIS project file that you can quickly open, modify, save, and redistribute as your own. We also include QGIS installers for Windows and Mac, so everything you need to get started is all in one place. And finally, all of the data and software operates entirely offline, with no need to connect to a license server, so whether you’re in a tent in Antarctica or in a coffee shop with bad wi-fi, you can still work on your maps!

Quantarctica was used in traverse planning for the MADICE Project, a collaboration between India’s National Centre for Antarctic and Ocean Research (NCAOR) and the Norwegian Polar Institute (NPI), investigating mass balance, ice dynamics, and climate in central Dronning Maud Land. Check out pictures from their recently-completed field campaign on Facebook and Twitter! Base image: RADARSAT Mosaic; Ice Rises: Moholdt and Matsuoka (2015); Mapping satellite features on ice: Ian Lee, University of Washington; Traverse track: NCAOR/NPI. [Credit: Quantarctica Project]

Every dataset in Quantarctica is free for non-commercial use, modification, and redistribution – we get explicit permission from the data authors before their datasets are included in Quantarctica, always include any README or extra license/disclaimer files, and never include a dataset if it has any stricter terms than that. We always provide all metadata and citation information, and require that any Quantarctica-made maps or figures printed online or in any publication include citations for the original datasets.

How do I start using Quantarctica?

Quantarctica is available for download at http://quantarctica.npolar.no/. It’s a 6 GB package, so if your internet connection is struggling with the download, just contact us and we can send it to you on physical media. You can use the bundled QGIS installers for your operating system, or download the latest version of QGIS at http://qgis.org/ and simply open the Quantarctica project file, Quantarctica.qgs, after installation.

We’re actively developing Version 3 of Quantarctica, for release in Late 2017. Do you know of a pan-Antarctic dataset that you think should be included in the new version? Just email the Quantarctica project team at quantarctica@npolar.no.

Quantarctica makes it easy to start using QGIS, but if you’ve never used mapping software before or need to brush up on a few topics, we recommend QGIS Tutorials and Tips and the official QGIS Training Manual. There are also a lot of great YouTube tutorial videos out there!

 

Nobody said you could only use Quantarctica for work – you can use it to make cool desktop backgrounds, too! Foggy day in the Ross Island / McMurdo Dry Valleys area? Though it often is, the fog effects image was created using only the LIMA 15m Landsat Imagery Mosaic and RAMP2 DEM in Quantarctica, with the help of this tutorial. [Credit: Quantarctica Project]

Quantarctica Short Course at EGU 2017

Are you attending EGU 2017 and want to learn how to analyze your Antarctic data and create maps using Quantarctica? The Quantarctica team will be teaching a short course (SC32/CR6.15) on Monday, 24 April at 13:30-15:00 in room -2.31. Some basic GIS/QGIS experience is encouraged, but not required. If you’re interested, fill out the registration survey here: https://goo.gl/forms/mLaJg686tZq8bm2N2 and feel free to send any questions or comments to quantarctica@npolar.no. We’ll see you in Vienna!

Edited by Kenny Matsuoka and Sophie Berger

Reference/Further Reading

Data sources

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Image of the Week – The Polar Hole!

Image of the Week – The Polar Hole!

Have you ever stumbled upon a satellite picture showing observations of the Arctic or Antarctic? You often see a circle where there is no data around the exact location of the geographic pole – as you can see in our Image of the Week. A few days ago, I wanted to explain this to one of my friends and turned to my favourite search engine for help. My search turned up a tremendous amount of stories and “scientific” studies about the Earth being hollow, with access to the centre of our hollow planet through these holes at the pole.

Obviously this is not the case. So here at the EGU Cryosphere blog we thought we’d better to set the record straight and explain the real reason for the “polar hole”.


Why do we need satellites?

Let’s start at the very beginning with how Earth observation data (e.g. temperature, ice cover, cloud cover, etc…) is collected. In the early days, measurements could only be collected pointwise, e.g. at weather stations (see Fig. 2) or by scientists traveling over land and by ship to specific locations. As a consequence, data coverage was very sparse and often clustered in places that were easily accessible, such as North America or Europe (Fig. 2). Additionally, measurements were even more sparse in hostile environments like the polar regions. It was therefore difficult to monitor these areas and study, for example, the evolution of polar ice sheets and sea-ice cover.

Since the 1970s, the use of satellites has greatly improved our ability to make remote observations around the world with a high spatial and temporal resolution, leading to much better monitoring of, for example, global weather and temperature. It has also allowed us to collect a vast amount of data in the difficult to access polar regions.

Figure 2: Map of the land-based long-term monitoring stations included in the Global Historical Climatology Network. Colours indicate the length of the temperature record available at each site. [ Credit : created by Robert A. Rohde from published data and is incorporated into the Global Warming Art project ]

Figure 2: Map of the land-based long-term monitoring stations included in the Global Historical Climatology Network. Colours indicate the length of the temperature record available at each site. [Credit: created by Robert A. Rohde from published data and is incorporated into the Global Warming Art project]

Earth Observation Satellites

Satellites orbiting the Earth allow is to make remote observations and measurements of what is happening in the atmosphere and on the surface of the Earth. Earth observation satellites are divided in two categories according to the way in which they circle (orbit) the planet:

    • Geostationary satellites: orbit around the Earth’s Equator at an altitude of about 36000 km. They orbit in sync with the Earth (taking around 24h to complete a rotation) and therefore are always pointing at the same region (see video below). They provide observations of a given region on a high temporal resolution. However, given their location at the Equator, they do not cover the polar regions well.
    • Polar orbiting satellites: circle the Earth at a lower altitude around 850 km and their orbit is nearly perpendicular to the Equator. They are not in sync with the Earth’s orbit, circling the the Earth around once every 100 minutes. They therefore cross polar regions several times a day. Have a look at the video below to see how this works!

So…we have polar orbiting Satellites – why can can’t we “see” the poles?

The answer: sun-synchronous orbits!

 

 

Sun-synchronous Orbit

To understand the data “hole” at the poles, we need to a little more detail about the path of polar orbiting satellites. To follow the evolution of a given point on Earth, it is useful for polar orbiting satellites to always cross that point at the same time of day – this way the angle of sunlight on the surface of the Earth is as constant as possible, resulting in a consistent series of images and observations over time . This is called a sun-sychronous orbit. To follow a sun-synchronous orbit, the orbit of the satellite has to be tilted at an angle from the geographic poles, thereby preserving the observed solar angle at the Earth’s surface .

Figure 3: These illustrations show 3 consecutive orbits of a sun-synchronous satellite with an equatorial crossing time of 1:30 pm. The satellite’s most recent orbit is indicated by the dark red line, while older orbits are lighter red. [Credit: NASA , illustration by Robert Simmon ]

Figure 3: These illustrations show 3 consecutive orbits of a sun-synchronous satellite with an equatorial crossing time of 1:30 pm. The satellite’s most recent orbit is indicated by the dark red line, while older orbits are lighter red. [Credit: NASA , illustration by Robert Simmon]

If you get a picture of all the trajectories of a sun-synchronous satellite, they will overlap (see video below), providing a seemingly closed picture. The only region that is not covered by the satellite is a circle (the size of the circle depends on the orbit tilt) around the geographic pole. This is the explanation for the data “hole” at the pole.

Sorry to debunk the myth but there is there is no hollow Earth that can be accessed through holes at the poles. The “Polar Hole” is a purely technical matter!

 

 

Further reading:

Edited by Emma Smith