Tom, Amélie and Russ started their journey North on the Dash-7.

As has become our custom, we leave you with the view of our flight tracks for this season.

You can also download the google earth flight track file.

Sorting gear and finishing packing and the shipping paperwork.

Hansiatic tourist ship called in and took Tamsin on her route home.

No flying today.

Took off all the instruments in the afternoon.

Poor weather today. No flying.

Amélie took a short flight 95 collecting local sea surface temperature data.

The first two twin otters left this morning and the base is very quiet after Folk Night.

Tom flew flight 96 in the afternoon to measure fluxes over the sea ice at the North of Alexander Island.

That's us about done apart from some calibrations/instrument investigations and the hope of one more Weddell Sea flight although the weather doesn't look promising for that.

Amélie headed off this morning over to the Weddell Sea to collect flux data on flight 94. She also tried to come back over the Dutch AWS sites but the cloud was too low over the Larsen Iceshelf.

Meanwhile, back on base Tom and Russ continued to look at data and start marking crates and consigning cargo back.

Dash-7 came back from MPA this morning and Fossil Bluff was closed this evening just in time for Folk night before the first pair of Twin Otters depart Antarctica tomorrow, leaving us the only people still flying.

The AWI Basler is also due through from Neumeyer via Halley in the next couple of days.

Looking good in the Weddell Sea today with pilot Mark but weather at Rothera and over the peninsula was very cloudy and he felt the icing would be too much.

So another day working on data. Amélie has produced plots of her sea surface temperatures on flight 91. Tom has been looking at the profiles from yesterday's flight compared to the Rothera radiosonde data. Russ has been writing notes on the kinematic GPS processing.

Tom flew flight 93 measuring conditions out to the west (and north) of Rothera to look at how well the Rothera radiosonde characterizes the conditions upwind of Rothera.

Tom and Amélie won a prize at the 'Pub Quiz' but it wasn't first prize.

Dash 7 North this morning with Hamish and Richard H on board for a lovely stay in MPA followed by the LAN Flight home via Punta Arenas, Santiago and Madrid.

Russ and Tom flew flight 92 over sea ice in the south of Marguerite Bay. Two lowest levels flown before we hit cloud. The BAT heater was not working folowing some settings changes investigating noise on the normal temperature sensor.

Two extra channels logged and also increased the frequency of temperature logging to see if averaging works. Data yet to be examined.

Resisted flying past the grounded tourist ship down by San Martin.

Still waiting for the right conditions for OFCAP, Larsen, Weddell Sea or further Marguerite Bay flights.

Flights home are confirmed as arriving UK Feb 28th.

We reprocessed the kinematic GPS from flight 88 with improved emphemeris (around 5-10cm change) and have now applied the EGM 2008 geoid 2.5' grid model and this removes most of the drift in height along the leg over the sea ice as well as reducing it to a feasible sea level, possible leaving tide effects as the bulk of the residual difference to zero.

The graph on the right covers the whole of the 1 hour leg showing the surface profile in black from the basic kinematic processing using WGS84 and the red with the improved emphemeris and EGM 2008 geoid model applied.

Isn't it great when all the mix of technologies and different branches of science come together!

The weather is again not suitable for any of our remaining flights. We cut out over a meter of tubing in the Licor inlet so we will be able to compare the change in delay we see with respect to the BAT probe data. Also checked the calibration on the Licor flow meter and that was almost identical to last year.

The air mechanics have the day off today and conditions are not right for any of our planned flights. The whole base has a relaxed Sunday feeling to it after the boatshed party last night. Most of the pilots and operations staff are away at Lagoon Island.

There has been lots of number crunching in the office. This image shows the principles of retrieving the surface profile and freeboard of the sea ice in flight 88 alongside an extract of the data.

More cloud around today. Amélie flew on flight91, looking at sea surface temperatures and other measurements around the West and South of Adelaide Island.

We also verified that there is a difference in GPS Time and UTC Time. Although GPS receivers usually display accurate UTC time, they have to subtract a correction as leap second corrections to UTC time have never been applied to GPS Time. Currently the difference is 15 seconds - see this and read more here.

We were quite pleased to find this was the case as comparing our kinematic GPS data to the rest of the aircraft data and other GPS position, it looked a bit like the back of the aircraft was arriving places 15 seconds before the front which is never good in aviation terms, however slow you might think the twin otter is.

Doesn't look like any suitable conditions for flying today, although another sunny day at Rothera.

It has been confirmed that we won't now fly with the cloud probe / pylons this season due to the documents BAS provided to ASSI being insufficient for approval. There is neither time nor money to correct this for this season.

On the data side of things, we managed to process the kinematic GPS data to improve the accuracy of the aircraft height figures which when added to the laser altimeter data of the flight over the Weddell Sea / sea-ice gave flat water areas to within a few centimeters.

No suitable flying conditions today. More questions and answers to/from ASSI regarding the cloud probe fit. We have been told not to expect to hear anything further until Monday now.

We spent the day testing the CAPS Probe and computer connected up on the aircraft. It was a worthwhle exercise as there were two problems with the power cables, one in the wing and one in the cables we use to connect to the aircraft. We checked that the time was sync'ing correctly between the 2 PCs and that we could view both the output screens.

Tom and Amélie used the spinning disk and particles to check the CAPS instruments. Then we took it all back out of the aircraft.

Russ managed to process the MAGIC kinematic GPS data for flight89, but this needs further work to see how we use this to correct aircraft height. Flight 89 is a good flight to use as it is over a large flat surface - Marguerite bay and a fairly short flight.

Amélie in charge today although everyone was up after an early morning toast fire alarm.

CAVOK at Rothera.

Logging software update and test required today before any flying after noticing that the Humicap inlet temperature and pressure were not logged on flight 89 due to picking up an incorrect configuration file.

Amélie and Tom flew flight 90 out over Marguerite Bay again.

Conditions very similar to yesterday, so no flying likely. Looks like it will be workable for the Larsen and perhaps have some westerly flow from the Bellingshausen Sea in a couple of days time.

Another question was asked by ASSI regarding the fitting of the CAPS cloud probe and BAS have responded. At least it shows they are actively considering the documentation.

No news on the CAPS probe approval today but the twin otters did get their 17,500 lbs ferry flight approvals so a lot of happy faces amongst the air crew who thought they might have to go home by ship!

We all flew flight89 in Marguerite Bay looking at Stable Boundary Layer structure. All went well apart from a few GPS dropouts.

Ali and Magda from MAGIC and the VIPs departed on the Dash-7.

A rainy day at Rothera. In the morning, conditions for a flight locally were ok but with air temperatures of +3 deg C, it was unlikely to produce the convective boundary layer conditions we are after. So no flying today.

The snow on the ramp to the skiway just the other side of the runway is disappearing rapidly in the rain today.

Deputy director of BAS is here with the royal party so maybe he will have some news about what is being done to get certification for the Cloud Probe before they leave tomorrow.

Formal meal for the visitors. Apparently the party was "almost as good as the King of Norway's birthday party". It must have been good as we have been forbidden from posting any pictures of the Dutch Royals!

Russ and Amélie flew over to the Weddell Sea piloted by David across the Larsen iceshelf (flight88). There were multiple cloud layers over the Peninsula causing icing which broke both of the BAT Probe fast temperature probe wires (FUSTs). The Licor inlet also iced up blocking flow into the instrument. Extracting the inlet tube into the aircraft did not cure this. The icing was in the inlet itself, which perhaps we could think about heating.

As we descended over the sea-ice most of the ice fell off and we did an hours flight up the coast over sea ice with open water patches/leads running the Licor and Laser Altimeter before returning to Rothera.

An early start to work on the aircraft as it was pulled out of the hangar to make way for the Dash-7 6am arrival with the VIPs.

We quickly established that there was a problem with the rear GPS antenna compared to the others. Later it was traced to the actual antenna itself rather than cables giving very poor or no reception and replaced it with the spare. Normal service resummed.

By this time the weather had closed in so it wasn't possible to repeat yesterday's aborted flight. We continued to get to grips with the data and also learnt how to operate the MAGIC GPS base station that we will use to get extra accuracy in attempting to get sea-ice freeboard data from the laser altimeter.

It looks like a flight across the peninsula over sea ice in the Weddell Sea might be possible tomorrow.

First thing, Tom took out the Hygrometer to clean the chamber and mirror, reassemble and squeeze the detector back in behind the oxygen cylinder. This resulted in it quikly reaching balance and without the rebalance light.

Amélie was kindly given a mini-DV cleaning tape for the downward looking video camera which was demanding to be cleaned before it would let us use it. She also set the clocks on the cameras.

Russ helped try and diagnose a fault on the MAGIC team aerial camera which had caused it to shutdown during flights.

After lunch, Tom and Amelie flew (flight87) just South of Rothera whilst Russ was programming to decode the new Humicap setup from the data. They had to abort the flight early due to lack of GPS aircraft attitude data. The Licor also wasn't collecting anything useful but this was quickly traced to leaking tube joints.

With the air mechs / ground crew trying to get some sleep before a 3am Ken Borek Basler departure and 6am Dash-7 arrival from Punta Arenas with the Dutch Royals we called it a day.

Another cool but sunny, almost cloud-free sky today. Stephanie mended our hygrometer cable in the avionics bay this morning (do avionics people go on special yoga courses to practice climbing into tight spaces?) and the instrument ground tests ok. Forcing a max-cool of the mirror sees a significant reduction in temperature now.

Russ performed a 2-point calibration of the LICOR (dry/scrubbed air and ambient air) to match the two cells. Hangar air now gives a believable 372 ppmv (compared to the accepted 385ppmv).

Tom was also successful in realigning the mirror in the CAPS CIP instrument. The test disk now gives perfect images.

Once the Dash-7 returned from Sky Blu after lunch we could use the runway for a flight to test the LICOR and Hygrometer (flight86). This turned into a double mission involving flying North and making two landings on the top of the peninsula on spots planned for field work by the US programme. It was most bizarre. We trailed skis, looked for crevassing then landed and left without stopping engines or getting out of the aircraft. All we left was a giant set of ski tracks. Felt a bit like the equivalent of crop circles for the Antarctic. Maybe we could get an Arts grant? It was spectacular scenery to be flying around on such a clear evening topped off with Minke and Humpback whale sightings in the fjord on the way home.

Both Licor and Hygrometer seemed to be working well. Now we have the licor reference cell pump on a low setting, it initially failed to start and the hygrometer was struggling with the low dewpoints below -20 C and indicates it needs a clean although in fact may be too clean. We'll give it a check in the morning anyway.

It was very satisfying seeing Licor and the frost point hygrometer, both measuring moisture content by two completely different mechanisms and showing the same forms in the fine scale structure.

Test flight (flight85) this morning with Mark, our pilot from the first season especially flown in from Halley. There were issues with the downward looking radiometers which were quickly fixed. The LICOR still has problems and is our main focus at the moment. The cooled mirror hygrometer also failed to work. This has been traced to having to remove the strain relief from the cable in order to fit it in around the oxygen cyclinder - two of the power wires have subsequently pulled out. Stephanie is going to rewire these in the morning. The sensor works fine on the bench test cable.

We have a copy of the FAA 8110-3 form for the CAPS probe covering structural analysis. This has now gone to ASSI in UK for approval. We don't know how long that will take.

A sunny day at Rothera. Completed fixing all the current snags with the instrument fit, ready to fly.

The Laser Altimeter problem was settings changes when we lent it out. The Licor problem was a cabling issue and internal connector related to modifying the instrument for Rob during the summer. New scrubber/drier chemicals were made up also. The De-Iced temperature sensor offset was traced to some protection diodes added this year and have now been removed!

Software changes were completed for the IRT black body and the Humicap temperature and pressure sensors. The PRT on this set was damaged and had to be replaced.

Our failed power feed relay was replaced by Stephanie.

The BAT Dome Temperature sensor mini-circuit failed while we were testing it and was replaced with the spare.

The Laser Altimeter was giving High Battery alarms running on 28.5vdc ground power. Not seen this before on the aircraft. Hopefully ok during operation from aircraft power.

Not being able to fly, Amelie went for a walk around the point in the evening, Tom went boating and Russ went for a run up to the skiway. I guess we spend enough time together during the day!

Halley transfer flight arrived and left back to Halley.

Finished mounting all the instruments (except CAPS of course) and sorted survival suits, sleeping bags and spare clothing.

Several problems identified once the kit was powered up in the hangar. The middle of the three aircraft power feed relays is not working the same as last year. We also experienced the same problems as last year with the BAT roof power connector. Cleaning the connections did not initially work but further continuity testing seemed to make a difference and that is now ok.

Still questions over whether the BAT temperature probes have loose connections.

Both the Laser Altimeter and LICOR were not functioning correctly having been loaned out during the summer. Hopefully this will just be a question of changing the settings back.

Software modifications are needed for the new IRT black body mechanism and the Humicap temperature/pressure channels.

The snowfall during the day had mostly melted by the afternoon and the three ALE twin otters departed North. Amélie's run on the runway was interrupted by an adelie penguin running the wrong way around the circuit!

Kyle completed the camera hatch floor panel with larger cutout in order to allow us space for fitting more instruments. Jamie finished working on the camera hatch skin panel to attach the new IRT bracket. All the instruments were mounted on the aircraft and the rack populated. We managed to rig the dewpoint mirror sensor in the avionics bay despite an oxygen bottle having been fitted in it's place which needs rectifying this summer.

The new roof positions for the radiometers and electronics work although we need to check the levelling of the radiometers and perhaps have some shims made up. The two new side rosemount inlets fit well and we will use those for the humicap and LICOR this year instead of the roof inlet.

Tomorrow we need to mount the IRT in the Camera hatch with the new black body mechanism and position electronics on the new floor panel as well as plumbing in the Licor. Then we will be ready for ground tests and might manage a test flight before the end of the day.

Now no possibility of having the certificate to fly CAPS Probe before Tuesday.

We tested the CAPS CIP with the spinning test disk as there was some noise in the images. This has not been fully rectified. We made up a power lead so that the spinning disk can be powered from the aircraft on the ground for tests without removing the probe from the aircraft.

However, we helped MAGIC remove their camera and Kyle took the camera hatch floor out to make us a template. All the instrument access plates were removed.

No real news on our certificate for the CAPS Probe and pylons to allow us to fly it yet.

Tom and Amelie are writing routines to read the CAPS data in readiness.

Jamie the air mechanic is working on mounting the new IRT bracket for us.

Russ ran up and down the ramp a few times before breakfast and converted the CAPS PC for 28 vdc use. Tom tested CAPS on the bench and it's looking ok after its travels.

An intense day of refresher training: medical; environmental; aircraft safety; vehicles; camping/fieldwork.

CAPS Probe and computers brought over to the office for testing. All our cargo appears to be here.

Most importantly the coffee machine has been PAT tested and commissioned!

Amélie took advantage of the great evening weather for a boat trip and Tom walked around the point.

Dash-7 flight from Punta Arenas to Rothera. We finally had the reassurance of seeing the BAT boom and CAPS Probe crates onboard after weeks of tracking them online and e-mails with the Chilean agents on their various travels from USA to Punta Arenas.

Talked with Alison and Magda from MAGIC about using their GPS receiver and base station with our Laser Altimeter. Sounds like this should work once they complete their flying.

Had a very constructive discussion with our pilot David and field operations manager Andy about what we are hoping to achieve and how best to go about it with regards to our first cloud flights.