Tag Archives: ice

Across Antarctica and beyond!

From Daniel Steinhage (AWI) and Steen Savstrup (DTU Space), Antarctica.

Daniel and Steen update us on their challenges of flying over Antarctica to get to the Concordia station and starting the DOMECair campaign. The aim of this novel campaign is to collect measurements that will validate ESA’s Earth observation SMOS water mission and GOCE gravity mission.

13 January
The overcast weather at Kohnen station finally cleared today so we were able to leave the Novo airbase, or Novo Runway as it’s commonly called, and head towards the South Pole. We had flown to Novo and met the AWI plane that we will use to take measurements for the campaign. The map below shows the distances involved!

Novo, Amundsen-Scott and Concordia highlighted in pink.

The flight involved crossing the Wohlthat Mountains, a mountain range that stick out through the ice sheet in central Queen Maud Land. The photo below shows the Nunataks, which are small areas of rock emerging above ice sheets and glaciers, and the ice-free mountain summits. In 10 days, we pass over this region again.

Aerial view of the Nunataks. (D. Steinhage)

After a short stop for fuel at Kohnen station we continued our transit flight and arrived at the Amundsen-Scott at the South Pole at lunchtime the following day. The station operates on New Zealand time, which is UTC+13.

Kohnen is a small summer station and at the time of our fuel stop it was occupied by 17 scientists and technicians from AWI. Amundsen-Scott at the South Pole, however, is a huge station, today housing 167 people. The station consists of a huge main building, garages under the surface and a large summer camp as well as several remote buildings dedicated to various fields of research such as atmospheric chemistry, astronomy and seismology.

Kohnen and Amundsen-Scott are both located on the East Antarctic plateau at heights of almost 3000 m above sea level. The temperature at Kohnen is slightly warmer, approximately –20°C, while at the Pole the temperature is –25°C.

At Concordia we expected even lower temperatures, so it is a major challenge to keep aircraft and scientific equipment warm enough to function properly.

14 January
We arrived at Amundsen-Scott just a few minutes before a C-130 cargo aircraft of the US National Science Foundation, so we could not refuel right away. This gave us enough time to grab some lunch and to settle into two temporary buildings used during the summer season. It had been a long trip and we had to struggle to stay awake until dinner. Straight after we’d eaten we went to bed – this was 19:00 local time, but being in UTC it was at 06:00.

Amundsen-Scott base. (D. Steinhage)

15 January
Today we received two contradicting weather scenarios for Concordia. Since Concordia operates at UTC+8 we had to wait until lunchtime at to get a weather report directly from them. However, we couldn’t rule out the possibility of incoming low cloud at Concordia, so we decided to play it safe and postpone the flight to tomorrow.

Since we had to wait, we ran some tests on our equipment. We wanted to see how the systems were dealing with the cold – the outside temperature dropped to –29°C and inside the cabin we were down to –10°C.

We also did reference measurements with the portable gravity meter at the gravity reference point at the station. The point is in one of the tunnels, which connect the main station building with garages, power plant, and the sewage system. The absence of any wind and the solid foundation allows precise readings, only the bitter cold – about –45°C made the work difficult.

Gravity reference point at the Amundsen-Scott station. (D. Steinhage)

16 January
We woke early at 05:00 o’clock to learn that the weather conditions were excellent. Forecasts from Amundsen-Scott and Concordia were similar so we packed and prepared the aircraft and instruments for an early start. By 09:00 we were airborne and on our last transit leg to Concordia.

Getting ready to leave for Concordia. (D. Steinhage)

Concordia is a station jointly operated by Italy and France. In winter, the station is occupied by about 15 scientists and technicians, but in the summer up to 65 people show up.

Before the station was established, the first of two deep ice cores of the European Project for Ice Coring in Antarctica (EPICA) were drilled at this site. This core holds ice oldest ice, dating back more than 840 000 years. The second EPICA ice core was drilled in Dronning Maud Land at the Kohnen station where we refuelled on our way from Novo Runway to Concordia.

Aerial view of Concordia station. (D. Steinhage)

Because yearly accumulation on the polar plateau is extreme low, just a few centimetres of snow, the summer camp at Concordia is set up year round.

Sunny weather for our landing at Concordia. (D. Steinhage)

17 January
After spending a night in a new time zone we woke up very early and were the first at breakfast. Nevertheless, it took a while to sort everything out so we could start to our first campaign flight.

We choose one of the two calibration flights to begin with, flying two sets of 10 circles. The second flight today is targeting two profiles of the planned 350 by 350 grid  around Dome C. By mapping lines, which are not adjacent to each other we are aiming to cover the grid with a wide spacing first, then fill in the profiles.

Between the two flights we carried out the first calibration of EMIRAD-2 with liquid nitrogen, the nitrogen had been especially flown in for us from the Italian base Mario Zucchelli.  Since it’s a dangerous substance, Concordia didn’t have enough for a complete calibration.

Liquid nitrogen calibration. (D. Steinhage)

18 January
Today we finished two-thirds of our scheduled programme. Among the flights we carried out are the star patterns centred on the American tower where RADOMEX from the DOMEX-3 campaign is mounted and currently obtaining data, along with two more lines of the 350 by 350 large grid.

Planned flights for the DOMECair campaign. (ESA)

19 January
We are slowly getting used to the low temperatures and high altitude of Concordia. However, the cabin is preheated every morning with a hot air blower. The only difficulty with the simple blower is that its temperature range is only hot or very hot.

This is sometimes a problem for the EMIRAD system, since it should be at a stable internal temperature while it is calibrated before take-off and maintain that internal temperature during the flight. However, by opening the curtains in the back of the airplane letting in cold air, and having the pilots operating the cabin heat appropriately, a reasonably stable ambient temperature for EMIRAD has been achieved.

Heating the cabin. (D. Steinhage)

20 January
Daily flight planning is based on the forecasts for the Dome C area that are received by email in the morning before breakfast. Later observations from Concordia station are also available from the radio office.

Owing to in-coming cloud around lunchtime, consistent with forecasts from both the US service in Charleston and the Italian meteorologist at Mario Zucchelli, and satellite pictures, we had to cancel today’s flight.

In the evening, we gave a presentation to the station personnel on our project. The lecture room was fully booked and many questions from the station personnel led to an interesting discussion.

 

Battling Arctic conditions for SnowSAR

From Chris Derksen (Environment Canada)  Inuvik, Canada

Although the schedule for the final preparations was very tight, activities are proceeding well for a SnowSAR flight in Canada.

Peter Toose and Arvids Silis stop for a break while en route from Inuvik to the study site. (Environment Canada)

Over the past week, scientists from Environment Canada have been in the field near Inuvik, in the Northwest Territories. As expected, the environment near Inuvik in December has posed some challenges – the Sun does not rise above the horizon at any point in the day, so between 11:00 and 16:00 it’s just twilight. Temperatures have been very cold, not climbing above –30°C and reaching as low as –38°C.

In spite of these conditions, measurements are proceeding well – Lidar scans to determine snow depth along large snow drift features are complete. Transects of snow depth, density, snow stratigraphy and grain size, and surface roughness are ongoing.

Alex Coccia from MetaSensing preparing to setup a calibration target for the SnowSAR. (Environment Canada)

The scientists are based in a small cabin approximately 50 km from Inuvik, which provides them with quick snowmobile access to the study area. They are enjoying the rustic lifestyle!

Arvids Silis from Environment Canada preparing to take measurements with a ‘magnaprobe’ – an automatic snow depth measuring device equipped with a GPS. (Environment Canada)

The Cessna-208 aircraft arrived in Inuvik from Norman Wells yesterday afternoon. The rear baggage doors were removed in the evening, and replaced with specially designed doors that will house the SnowSAR instrument. Installation of the SAR is planned for this morning, and if weather conditions cooperate, the science flight will be conducted this afternoon.

The campaign supports the development of ESA's CoReH2O candidate Earth Explorer mission.

New CryoSat ice campaign kicks-off up north

From Malcolm (ESA), Kangerlussuaq, Greenland, 28 March

On-route to the high Arctic

After months of preparation and  hundreds or even maybe even a thousand emails, the 2012 CryoSat Validation Experiment otherwise known as ‘CryoVEx 2012’ finally kicks-off this week across the Arctic.

Together with NASA colleagues and participating scientists from the USA, Canada and Europe, some remarkable airborne flights are planned later this week and early the week after.

One of the highlights could come as early as tomorrow when the CryoSat satellite will pass over the Arctic Ocean from the north at about 7 km per second and pass almost directly over the Canadian military base Alert located at the northern tip of Ellesmere island. This provides an ideal occasion to fly directly under the satellite and collect valuable data from the onboard instruments on the real ice-conditions and ice thickness beneath both plane and satellite.

For the moment, however, I’m in Greenland still travelling to the campaign location. Reaching the isolated Alert base is itself a challenge and typically takes two to three days or more, albeit through some interesting and spectacular landscapes.

Landing in the main port of entry into Greenland – Kangerlussuaq – I was greeted appropriately by a snow storm as you can see in the picture of the ferry plane between Europe and Greenland. If all goes well I’ll be in Alert tonight or tomorrow evening. In the Arctic, however, you never know as weather can change quickly. Let’s see!

Sea ice conditions around Alert

From Mark (ESA), in Noordwijk, NL

Here are a couple of satellite images showing the current sea-ice conditions around Alert in northern Canada.

AVHRR/NOAA image showing large area around Alert, Canada Credit: DMI/Polar View

AVHRR/NOAA image showing large area around Alert, Canada (Credit: DMI/Polar View)

The first is an AVHRR image from NOAA, courtesy of DMI/Polar View, and shows a large area perspective of the Lincoln Sea (upper part), Nares Strait (lower left) and Northern Greenland (lower centre). The marked box indicates the location where the following image focuses.

A large-scale fracture pattern and relatively dark shear lines can be observed running through the sea-ice pack. They are caused by the sea-ice drift pushing ice against the coast of Northern Greenland. A relatively dark zone of divergence or opening occurs where ice escapes eastwards around the northern tip of Greenland into the Fram Strait (centre right of the image).

This next image, which is an ASAR image from Envisat, shows the regional sea-ice details off Alert. It depicts in light grey and white tones, the old, multiyear ice pack along the Ellesmere Island coast (at left centre) and Greenland coastline. The black border (upper left) indicates the edge of the SAR image swath.

ASAR/ENVISAT image showing ice detail off Alert, Canada (Credit: ESA)

ASAR/ENVISAT image showing ice detail off Alert, Canada (Credit: ESA)

The Envisat image was acquired on 14 April at 15:48 UTC.

Up and away

From Malcolm (ESA), NL on 8 April
Just leaving ESA in the Netherlands for my flight to Alert in northern Canada to start the campaign – which has to be one of the biggest I've organised in my 10 years at ESA.

Twin Otter (credits: DTU)

Twin Otter (credits: DTU)

The two planes we have dedicated to the campaign will arrive this weekend along with other team members from Europe and Canada. So, hopefully we'll be kicking off with the first flights on Monday.

We've got a Twin Otter arriving from the Technical University of Denmark that carries the ASIRAS instrument. ASIRAS is an airborne instrument that was developed specifically to mimic the radar altimeter on the CryoSat satellite. In addition, we have a Basler-67 from the Alfred Wegner Institute, which is equipped with an electro-magnetic ice-thickness sensor.

So, while the planes take measurements from the air, team members will be out on the ice taking ground measurements. Apparently it's about -30°, so it's going to be a challenge.

I'll be spending the two weeks out in Alert, based at a military centre. From there I'll be covering the main activities before nipping back to NL for a week and then heading straight off to Greenland for another leg of the campaign.

NASA are already well into their IceBridge ice survey campaign and things seem to be going well with that. During the campaign, NASA is going to be carrying out several flights for us – underflying CryoSat. This is a great example of cooperation between our two space agencies.

I'm really looking forward to starting the campaign. It's been a lot of work to organise – we have over 50 people participating from 15 organisations, not counting ESA. So, now actually getting off the ground marks a real milestone!