Tuesday, January 21, 2014

Mapping the Earth’s Polar Regions

Ross Island with Beaufort & Francklin islands

From GISLounge

The Earth’s Polar Regions, Antarctica and the area within the Arctic Circle, are the most inhospitable places on the planet for humans.
Yet, scientists and researchers continue to explore and map these regions in order to get a better understanding of their importance.
It is widely believed that the Polar Regions hold keys to unlocking other scientific mysteries and can reveal what the future holds for the Earth and all of its inhabitants.
In order to better understand the Arctic and Antarctica, there is a constant need for better-quality maps to be produced.
Southern Hemisphere, NGA

One of biggest steps taken towards supplying better maps of the Polar Regions has been recently completed by the Polar Geospatial Center (PGC).
The center, located at the University of Minnesota, has released and made available a series of web-based applications using high-resolution images and maps showing the Arctic and Antarctica in unparalleled detail.
These images are of an improved resolution and more up-to-date than earlier mapping projects of the Earth’s extremities.

Previous mapping projects of Antarctica include LIMA, a mosaic of Antarctic images based on NASA’s Landsat satellite program.
High-quality images of the continent were compiled into an all-encompassing satellite view and released in 2007 as The Landsat Image Mosaic of Antarctica (LIMA).
LIMA was the result of collaborative efforts from the U.S. Geological Society, NASA, The British Antarctic Survey, and the National Science Foundation (NSF).
What is distinctive about LIMA was the quality of its images.
The project brandished images in 15-meter resolution, and it was the first true color, seamless map of Antarctica that was virtually cloudless.

The LIMA mosaic is based on approximately 1,100 images taken from 1999 to 2001 from the Landsat-7.
The project was developed as part of the International Polar Year back in 2007-2008 in order to educate people about Antarctica and demonstrate how scientists use GIS data to study the continent.
One disadvantage, however, is that the LIMA mosaic does not cover the whole continent.
A portion is left off of its satellite view from the South Pole at 90 degrees latitude to 82.5 degrees south latitude because of gaps in Landsat’s coverage.

Franklin Island to McMurdo Sound
Naval Oceanographic Office (NAVOCEANO)

Nevertheless, the Polar Geospatial Center has taken polar mapping to the next level with their web-based applications.
Using commercial imagery from the National Geospatial-Intelligence Agency, these maps of Antarctica offer a resolution 900 times better than that from LIMA and come within thirty kilometers of the geographic South Pole.
According to the PGC’s director Paul Morin, their maps and applications can show every rock outcropping, every penguin colony, and every crevasse.
Moreover, the Polar Geospatial Center has the ability to shoot images of Antarctica that are at a 50-centimeter resolution every forty-five days.

 Map of South Pole (1843)

In 2007, the Polar Geospatial Center was established in order to provide geospatial services to Antarctica. It mainly supported the U.S. Antarctic Program and was funded by the National Science Foundation.
Since then, the PGC has expanded into doing its own fieldwork using geospatial data for the purpose of solving critical questions concerning the Polar Regions.
The PGC also produces geospatial products for individual use.
Their Imagery Viewers allow its users to create their own maps of locations in Greenland and Alaska as well as Antarctica.
US Navy Operation Deep Freeze IV 1958-59

Web applications based on those types of high-resolution maps have incredible, almost limitless potential.
The Polar Geospatial Center’s online maps can handle just about any request they get from scientists and researchers.
The project was hardly simple, however.
It took the PGC over eighteen months to complete, and one of the biggest challenges was fixing the orientation on an immense number of images.
Instead of being shot at a vertical, these images were shot at an angle from commercial satellites owned by DigitalGlobe, Inc. and had to be corrected.


To make these images of the Polar Regions more accessible to scientists and researchers, the Polar Geospatial Center has developed several web-based mapping applications, and they can be utilized in GIS software.
The Imagery Viewers are three such mapping applications which cover much of Alaska, Greenland, and Antarctica.
Some of the features of the maps include placename search, satellite imagery basemaps, and georeferenced maps.
Unfortunately, the Imagery Viewers are only accessible to federal government employees and researchers with federal funding, not to the general public.


However, the PGC offers other web based applications.
One of them, called the Antarctic Air Photo Viewer, enables users to search, view, and download Antarctic aerial photography.
These photos are offered in two different resolutions.
Plus, users of PGC’s RapidIce Viewer can search for and download over 500,000 unique satellite images of pre-set places in Greenland and Antarctica.
These web-based mapping applications can provide a large variety of uses.
For example, Joe Levy, a scientist at the University of Texas at Austin used the images to study the melting of buried ice at a specific location in Antarctica.

Overall, the hope is that improved maps of the Polar Regions will give scientists and researchers enhanced tools for solving the mysteries of the planet.
Tools like LIMA and the web-based mapping applications from the Polar Geospatial Center proves that remote sensing technology can greatly increase our understanding of even the most forbidding and barren areas on the Earth.

The monthly Sea Ice Index provides a quick look at Arctic-wide changes in sea ice.
From the National Snow and Ice Center.

Links :  Polar Mapping Resources:

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