Media Release

Icy News - Australian Antarctic Division

Science in the field

Our journey started with a meteorology briefing, like any other flying day. The weather is good, let's jump in the helicopter.
Beaver Lake is located in the Prince Charles Mountains, an almost three hours flight from Davis station. With a helicopter, it means flying first to Sansom Island, refuelling, having a break, and then continuing our trip to Beaver Lake.
The trip to Sansom Island is worth the refuelling: in the middle of the Antarctic summer, the glaciers and icebergs are colorised by the melting pool from the surface melting, forming the deepest and purest blue one has never seen. Their shapes leave our imagination sailing, from the camel shapes to hearts.
Sansom Island is the last piece of rock on the coast before the great white of the Amery Ice Shelf. From there, we fly south, keeping in sight the spiky rock of the Prince Charles Moutains, growing and growing over an hour.
Here they are, encircling Beaver Lake, the famous frozen lake shaken by the tides. The antenna unit which has been installed in the past is shining in a gorge, at the bottom of the mountain jaw. After a few minutes flying over, we can spot it. Now we start our job: setting up a GPS unit with two batteries using the previous antenna, and then record its position for over ten days.
This is a way for the geophysicists to measure the uplift of the crust in that area. This movement is created by the post-glacial rebound, the mantle pushing the crust as a consequence of the last deglaciation and disparition of the ice pressure on top of it.
But the signal is tiny: only few millimetres per year. Over ten years our GPS is able to record the change. The GPS installation is supposed to be easy, only a few minutes are required to plug in the batteries, the antenna and the GPS, but this is without dealing with the Antarctic wind blowing. The helicopter can hardly land: in few minutes we empty the helicopter, install the unit and jump back in the chopper.
Good luck GPS. Let's see you in 10 days full of useful data. We are now flying back to Davis with the sun touching the horizon.

A bientôt !

Lydie

L. Lescarmontier working at one of the GPS sites (Photo: V. Emetc)

Scenery surrounding Landing Bluff, one of the location of the GPS site. (Photo: V. Emetc)


News - Australian National University 


Enderby Land’s massive mystery
Dr Lydie Lescarmontier (Photo: V. Emetc)

Something massive is going on in East Antarctica’s Enderby Land and a team of researchers from the Research School of Earth Sciences are on their way to investigate.

The first hint of mystery came from the GRACE (Gravity Recovery and Climate Experiment) satellite which showed an increase in mass in the area between Australia’s Mawson and Japan’s Syowa stations known as Enderby Land. GRACE measures changes in the Earth’s gravity field which in turn gives researchers an indication of a continent’s mass.

“Typically we see these changes in gravity in Antarctica with ice loss or accumulation, post glacial-rebound, or a combination of both,“ says Dr Lydie Lescarmontier, who will work with PhD student Bianca Kallenberg to unravel the mystery.

It’s a long trip to the site for Lescarmontier and Kallenberg, who will travel on the ice breaker Aurora Australis to Davis Station, before flying to Mawson station, then on to Enderby Land. When they arrive at the Richardson Lake site, Lescarmontier and Kallenberg will construct two autonomous solar powered GPS observing sites which can measure changes in the uplift of the rock surface under the ice as precisely as a millimetre a year.

“Satellites like GRACE only measure the change in mass but can’t tell you where that change comes from. These GPS will measure the Earth’s crust,” says Kallenberg.

GPS measurements from the Richardson Lake area between 2007 and 2008 showed no significant crustal uplift, but were taken at a time when the GRACE data also showed no change. The new installations will extend the GPS record and answer definitively whether the GRACE signal is due to snowfall or long-term uplift, which in turn will help researchers understand whether their future global sea level predictions need adjusting.

“We already have records from the first [Richardson Lake] site from 2007/08 so we want to see the difference between these dates and today,” says Lescarmontier. “The second site is a new site so we don’t know what to expect.”

Lescarmontier is a veteran of four Antarctic field seasons with the French Polar Institute IPEV.  She is now preparing to go south with the Australian Antarctic Survey.

Kallenberg will be travelling to Antarctica for the first time: “I am very excited. When I started my PhD I was hoping I might have the chance to go to Antarctica.”

You can follow Lescarmontier and Kallenberg’s Antarctic adventure on their Enderby Land Project blog.

Greencarer

Scientists shipped far south after mysterious metering


Gravitational shifts have indicated something strange is happening in Antarctica, and a team of researchers from ANU are on their way to check it out.

Dr Lydie Lescarmontier on the Mertz Glacier

A mysterious clue was given up recently by the GRACE (Gravity Recovery and Climate Experiment) satellite, which measured an increase in mass in the area known as Enderby Land, between Australia’s Mawson and Japan’s Syowa stations.

Land mass increases could mean a lot of things, so a team is going down to try to work it out. There could be implications for numerous climate models based on the height and mass of Antarctica.

“Typically we see these changes in gravity in Antarctica with ice loss or accumulation, post glacial-rebound, or a combination of both,“ says Dr Lydie Lescarmontier, who will work with PhD student Bianca Kallenberg to unravel the mystery.

It will be no weekend jaunt down to the snow, with researchers shipping over on the ice breaker Aurora Australis to Davis Station, before flying to Mawson station, then on to Enderby Land.
Once on-site, the team will put up two autonomous solar-powered GPS observing rigs. The devices will measure changes in the level of the rock surface under the ice, gathering figures as precise as a millimetre a year.

“Satellites like GRACE only measure the change in mass but can’t tell you where that change comes from. These GPS will measure the Earth’s crust,” says Kallenberg.

“We already have records from the first site from 2007/08 so we want to see the difference between these dates and today,” says Lescarmontier.

“The second site is a new site so we don’t know what to expect.”

The measurements will hopefully shed some light on the relationship between satellite and ground figures, as well as what is causing the ground level to change; it could be snowfall, long-term uplift, or some other element.

Whatever is making the mysterious measurements needs to be tracked down. The height of land in Antarctica is the basis for many climate models, and must be calculated with extreme precision.

Reports from Lescarmontier and Kallenberg’s Antarctic adventure will be posted on their Enderby Land Project blog.

Which horror movie is ANU sending its researchers into? [With Poll]


map screenshot
It sure as hell sounds like the start to a horror movie over at ANU:
Something massive is going on in East Antarctica’s Enderby Land and a team of researchers from the Research School of Earth Sciences are on their way to investigate.
The first hint of mystery came from the GRACE (Gravity Recovery and Climate Experiment) satellite which showed an increase in mass in the area between Australia’s Mawson and Japan’s Syowa stations known as Enderby Land. GRACE measures changes in the Earth’s gravity field which in turn gives researchers an indication of a continent’s mass.
“Typically we see these changes in gravity in Antarctica with ice loss or accumulation, post glacial-rebound, or a combination of both,“ says Dr Lydie Lescarmontier, who will work with PhD student Bianca Kallenberg to unravel the mystery.
Which horror/scifi movie is ANU sending its staff into?
There’s a blog to follow the unfolding horror from beyond the stars on.



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