The benefits of snow…

Geoff Evatt | 02 Jan 2020

The cloud has lifted and progress has been made. Yep, in a true A-team style our patched-up systems seem to be working (as in, two systems with a combined searching width of 4 meters). And we searched for almost 8 hours. No subsurface meteorites,  yet (statistically,  we are only expecting a handful of iron meteorites over the entire 12km2 ice field). But what is certain is that if we’re not searching then we can’t be finding them.

As for conditions, well, it’s now all snow covered,  meaning no blue ice is visible anywhere. Whilst this makes the subsurface searching easy to progress (because you can see where you’ve been and removes vibrations in the system), it makes seeing any surface meteorite impossible. Personally I’m hoping the snow cover lasts for the rest of the trip!

The next couple of days are forecast to be similar nice weather with low winds. So let’s see if our relative fortune holds for tomorrow.

Bon réveillon a tous !

Romain Tartese | 31 Dec 2019

Une fois n’est pas coutume, voici un blog en français pour les quelques 3 ou 4 francophones qui suivent notre périple Antarctique ! Ça fait maintenant une dizaine de jours que nous sommes réunis tous ensemble sur notre zone de recherche de météorites, par 81° de latitude sud. En général la météo a été plutôt clémente jusqu’à présent, avec de belles journées ensoleillées accompagnées d’une légère brise venant de l’Est, et des températures généralement entre –10°C et –15°C. Jusqu’à maintenant nous n’avons été ‘coincés’ au camp que deux journées, et on croise les doigts pour que cela dure.

Nous avons donc pu arpenter en motoneige une bonne partie du glacier à côté duquel nous sommes basés, et avons collectés une cinquantaine de météorites à la surface (à ajouter aux 15 météorites collectées sur ce glacier l’année dernière par Katie et Julie). Il a pas mal neigé ces derniers jours et malheureusement la glace est maintenant couverte par 5-10 cm de neige, ce qui rend la recherche de météorites a la surface impossible pour le moment. On espère donc de bonnes bourrasques de vent pour dégager la neige du glacier, et continuer notre collecte.

Une belle pièce ! [Crédit : Katie. Joy]

Dans le même temps Wouter et Geoff ont fait face à pas mal de problèmes avec les détecteurs de métaux que nous trainons derrière nous sur la glace — les vibrations ne font pas bon ménage avec les boitiers électroniques. Mais à chaque problème il y a une solution, et au jour d’aujourd’hui nous avons 2 systèmes qui fonctionnent. Il nous reste deux grosses semaines pour couvrir le plus de surface de possible avec les détecteurs de métaux afin d’essayer de trouver une météorite ferreuse enfouie a quelques dizaines de centimètres sous la surface (nos estimations prédisent quelques météorites enfouies pour une surface d’environ 10 kilomètres carrés !).

Si on dégote une boite de thon on va se faire une ‘gueuleton’ ce soir pour le réveillon, à base de pates, thon et sauce tomate ! De votre côté, n’abusez pas trop sur le foie gras ! Nous vous souhaitons un bon réveillon a tous, et un très bon début d’année 2020 !

New year, new start?

Geoff Evatt | 31 Dec 2019

Hello from Outer Recovery as we approach the end of the decade. Low cloud and poor contrast abounds today, so we’re confined to the camp, giving us the chance to tinker with the system and get some rest (the ambiance outside is currently Nordic,  and not unwelcome). The last few days has seen clear positive progress.  As in, we seem to have salvaged a working core of the detector system. And we have been out doing systematic searches with it, covering a reasonable area, all things considered. Issues seem to pop up every 3 hours or so, but in those hours the system is working amazingly well. In fact, after some re-engineering of a sledge yesterday, we finally have two operating systems (one as 5 panels although only three of these are working, and the other is now a single panel system), meaning we can search a width of 4 metres as we travel along. Let’s hope those 3 hours of search time start creeping upwards…. this whole project is a numbers game: the larger area of the ice field we can search, the more likely we are of finding a lost iron meteorite.

Katie and Wouter soldering. [Credit: Geoff Evatt]
Wouter using parts of one metal detector to fix other. [Credit: Geoff Evatt]

Other than that, our surface meteorite count for this season is now 42, which is great, especially given the relatively small area we are searching (this blue ice field is just under 12 km2, but maybe a fifth is hidden by sastrugi, making it impossible to search). After strong winds the other day, some of the snow cover altered, and Katie and I found a nice chondritic meteorite where a sastrugi existed the day before.

Sledge Evatt getting some TLC. [Credit: Geoff Evatt]

Food-wise we seem to be doing OK.  It appears the vast number of calories we had at Rothera cause our metabolisms to increase, meaning that when we first hit the field with far less food, we rapidly got thin. But now our bodies seem to have taken the hint, and the weight loss seems to have slowed. Or maybe we’re just eating more biscuits brown and porridge. Does this mean we’ll balloon as soon as we hit civilisation again? Either way I’m desperate for a run or cycle, but conscious that the general wear and tear on the body may mean it’ll take a while to be back to normal. Yet I can now drag metal detector panels for Britain. Maybe we now have the world record for doing so down here?!

Romain driving one of the detector arrays. [Credit: Geoff Evatt]

Getting surface meteorites in the bag

Katie Joy | 27 Dec 2019

Whilst the panel testing is continuing (see Geoff’s last blog post) we have also been making steady progress with searching the ice surface for meteorites that have emerged from the blue ice. As of today the count is at 35 stones from Outer Recovery — one off the total for the whole of the last recon field season.

Katie and a large meteorite “find”. [Credit: Romain Tartese]

Every rock we locate at this particular ice field is a meteorite — there are no terrestrial rocks at all, so it makes identification very easy. What is tricky is actually spotting them in the first place — often the meteorites are hiding at the bottom of suncups (small depressions made as the ice is ablated by the wind and sublimated on warmer days), and for those less than a couple of cm in size you have to be lucky to see them as you drive past on your skidoo and be looking in the right direction (for this reason we swivel our head continually as we drive like watching an end-to-end tennis match). Samples bigger than ~3 cm are easier to spot, but again can sometimes be nestled down between snow patches or in suncups. Whether you are driving into the sun, and the angle of the shadows cast at different times of the day comes into play, so although we are systematically trekking back and forth across the ice surface, not every search session results in a meteorite find: between 2 and 7 meteorites seems to be the rate of daily collection at the moment.

A small but perfectly formed flight orientated stone. [Credit: Katie Joy]

The meteorites themselves vary from a small bean-sized one we found yesterday (a lovely perfectly fusion crusted stone, suggesting that this tiny meteorite is a complete piece), to another complete stone which preserves a fusion crust that is flight shaped (i.e. we can tell which in orientation the meteorite was delivered as it travelled down through Earth’s atmosphere — these type of samples are very aesthetically pleasing, and are really cool to find), to some larger blocky stones (around the 8-20 cm size range) that look like they are pieces of a large meteorite that broke up either in space, or through erosion as it was transported through the ice [NB I am guessing that they are from the same parent meteorite at this stage based only on the colour and texture of their exterior surface, and the very similar colour and texture of their interior — this will all need to be confirmed when we do the formal classification back in the lab]. Several of the samples we found this year are like some of those we found last year, suggesting that again there might be some relationships between the samples we have collected, and others look completely different which is exciting as it means we have good diversity across the sample set collected.

So, all in all, we are progressing steadily, and hopefully will continue to get more meteorites bagged up. Today the weather has turned snowy so will have to see how this effects our search plans over the next few days.

Hope that everyone had a Happy Christmas — we had a tasty meal last night together complete with an amazing Christmas cake provided by chef Olly at Rothera (many thanks — you are a star!), and had a team drive out after testing the panel array to visit a cool ice rise (which is a bit of ice that has been squeezed up to look like a pointy mountain tip) next to the search area.

Geoff driving the detector panel arrays on the ice surface. [Credit: Katie Joy]
The team visiting a nearby ice rise on Christmas Day. [Credit: Katie Joy]

PS Many congratulations to my Aunty Angie and Tommy for getting engaged. Sorry I cant be there to celebrate with you all, but raising a cup of tea to you from the field.

PPS Thanks Isotope Group crew for sending down the birthday card. Very sweet of you all to get so organised in advance. 🙂 Much appreciated. Hope that you are all well and looking forward to the BPSC.

PPPS Dutch, we found some pina-colada flavoured energy bars in the manfood box. Definitely not as exciting as the real thing.

The weather outside is frightful…

Geoff Evatt | 26 Dec 2019

Hello from Outer Recovery,  where we are spending Boxing Day cooped up in our tents as the weather outside is not so great today…. meaning I have the chance to give a status update.

Working on the detector system. [Credit: Katie Joy]

All of a mixed bag really. The positive news is that we have begun searching for the lost meteorites! And when searching, the system is performing rather well (we can see our trial targets down to almost 20cm in real time, with minimal false positives). The bad news is the combination of vibrations, cold, and extended periods of operation are battering the system, meaning we are spending most of the time patching it up.

Views from a Christmas Day walk. [Credit: Geoff Evatt]

To give an example, yesterday we found the main power cable from the solar panels to the batteries had snapped clean through, in two places.  This cable was Antarctic rated and successfully used in other projects. But the high pitch vibrations being put through the system by the scalloped ice surface, means that even the tiniest of weaknesses are soon exploited. And this particular one has consequences: as it snapped it caused the solar panel regulator to be permanently damaged, meaning we can no longer use the solar panels to charge the batteries, so we have to rely on a generator, which in turn means it takes much longer to charge the system…. and that’s after several hours of trying to identify and fix the problem…. This example shows what we ‘re up against. And with the whole search being a numbers game (for this particular ice field, we have predicted 3-4 subsurface iron meteorites) then, we have to search a large area to stand even a slight chance of finding one. But we are progressing, albeit haltingly.

Meteorites in hand! [Credit: Geoff Evatt]

In other news the surface search is moving forwards well, with over 30 meteorites collected so far. From their appearance we seem to have collected a good diversity of samples, which is welcome news. We had predicted around a hundred meteorites on the surface for this icefield (give or take), and as that includes the 15 found by Katie here last year, then we are moving steadily towards that estimate. And that’s not taking into account that the blue ice area has over a 20% snow covering, meaning over a fifth of the predicted meteorites are out of view.

We also managed to ascend the ridge overlooking our camp yesterday, to find a stunning view down over the blue ice plains below, with (surprise!) yet more Antarctic plateau behind. It was a great way to round off Christmas Day, before heading back to a lovely smorgasbord of food and cake.

In the meantime we’re sitting out the bad weather, and about to commence with yet more repairs on the system….

Sunny skies and finding meteorites

Katie Joy | 22 Dec 2019

The team is all together now at our Outer Recovery fieldsite! The last few days have seen a lot of activity. On the 19th I flew from Halley with pilot Mark to drop off the science kit at Outer Recovery with Wouter and Geoff — this included the final set of panels and our meteorite extraction equipment. Then a series of short 30 minute flights took us to a refuelling depot, over to Romain and Taff to collect a skidoo and a Nansen sledge, back to Geoff and Wouter to drop these off, back to refuel the plane, then back to Romain and Taff to pick them and the final skidoo up, and finally drop everyone off at Outer Recovery site.

The team looks onto a recent find. [Credit: Katie Joy]

It was a pretty long day with a lot of flying, with a lot of skidoo loading and unloading onto the planes (this whole exercise is a right pain in the butt – the skidoos just (just) about fit through a Twin Otter door and it takes four people to rotate, bump, pull and push them in and out of the plane). Finally, we were all together as a team, and the next day we waved goodbye to fieldguide Rob who returned with pilot Mark to Halley, before moving camp 2 km down the road (or rather sastrugi-covered surfaces) to set up on the edge of the blue icefield where we will be working. It has been sunny, cold but very windy (we reckon about –22°C with windchill) at the field site. Yesterday, the summer solstice, brought a day where we explored the ice surface, finding 7 more surface meteorites (a nice mix of shapes and sizes, with several looking different to each other), and did some more in-field testing of the panel arrays – we have been burying small iron dummy meteorites to tune the system to working on ice (rather than the rocky cargo yard at Rothera, or the soil field at Whaley Bridge).  The wind has dropped, the temperature is up and today the plan is to do another testing round out on our practice search area to get the system finalised. Hopefully we will be in a position to begin buried meteorite searching soon, and in the meantime will do some more surface searching. 

Geoff with a recent meteorite find. [Credit: Romain Tartese]

Hello from Outer Recovery!

Geoff Evatt | 19 Dec 2019

It has been a while since we gave an update on matters here, mainly because we have gone from prolonged inaction to lots of action. To recap, we (Wouter, Rob and I) were originally dropped in at the southern end of the Outer Recovery Ice Fields, but without skidoos.  This meant that any exploring was confined to a very short distance from the tent. And without a generator to charge our batteries, it meant occupying our time was slightly challenging. Once we had tested all we could with the science gear we had, we were left with no choice but to build an igloo (it is glorious). Adding to the amusement of matters is finding about one in ten of the dried food sachets gives instant food poisoning; when trapped in a three person tent this does add spice to life.

Then after a week, a couple of skidoos were brought out to us by pilots Dutch and Mark.  We were then free…. free to move to our intended camp location on a blue ice area in the middle latitudes of Outer Recovery.  Conscious of lots of crevasses, we slowly made our way there. It took two days to shift all of the science gear and camping stuff, but in so doing it allowed us to commence with the first stage of the project: testing the gear (yes, again). Without going into too many details yet, the electronic side of the system is not loving the conditions at present. The mechanical side is fairly relaxed and proving reliable enough. This means the next few days will be critical for us.

Field guide Rob tows the metal detector array across blue ice [Credit: Geoff Evatt]

Yet during the first trials of our equipment on the blue ice field, Rob suddenly gave a yell: a large black lump some 100m away. Yes, he had spotted our first meteorite! A real whopper as well. And as the day went on we found more and more (all within a couple of hours search time). As it stands we appear to have found, we think, some 8 meteorites — and five of them are relatively sizeable. We were all extremely excited to have found them and to be off the mark: we will not be going home empty handed!

One of the first meteorite finds [Credit: Geoff Evatt]
Off the mark. [Credit: Wouter van Verre]
Another! Rob Taylor with another ‘find’ from foot searching [Credit: Geoff Evatt]

As for everyone else? Well, it looks like we’re suddenly going to be all together tomorrow. The logistics behind this project have been huge (thank you all at BAS), and hopefully we’re near the end of the to’ing and fro’ing. All hands will then be focused on getting the camp fully set up, and then seeing what we can do with the detector system (our science tent will primarily be an electrical engineer workshop).

As for weather? Slightly mixed, but on the whole rather sunny. This certainly helped keep us sane during the close quarters camping. The temperatures are probably down towards –20ºC, although without any of us having a thermometer it’s a bit of a guess: when the nostril hairs freeze up (slightly) as you inhale, then you know it’s below –15.

We’ll be in touch again shortly with updates on sledge matters, and hopefully some more meteorite news.

In the meantime we will say goodbye to our field guide Rob Taylor, who Wouter and I have been fortunate to have look after us — especially his “Spamghetti” surprise dinner (can you guess the surprise?). Thank you Rob, you have been fantastic. He now heads back to Halley for a shower and some non freeze-dried food (he was only expecting to be out here a couple of nights) and gets swapped for field guide Taff.

Answering some questions from Hope Valley College

Geoff Evatt | 19 Dec 2019

Many thanks to the students at Hope Valley College for their questions about Antarctica and what it’s like living out there for our field work. Thanks for your interest!

Q1. What is it like to survive in such cold conditions?

A1. It does indeed feel like survival! After all there’s no chance of growing your own food here, and we have to melt ice to make drinking water. As such, when here in Antarctica we are, by necessity, reliant on technology from the warmer parts of the world: travel is generally by planes and skidoos, we wear several layers of clothing and very thick boots, food is freeze-dried food, and ice is melted by burning kerosene. Even going to the bathroom (in a very cold toilet tent) is a different process, as there are no bacteria to break the waste down. And so when camping out here on the ice sheet, some 800km from the nearest base, we are constantly taking advantage of the latest advancements from back home — including the Iridium satellite device that allows me to send this message. But the advantage of all this is that it allows us to do science in a very special place (when the weather is tolerable) — in this particular case, to look for meteorites.  Without these technologies and advancements we would not be able to survive here for long, it’s just too cold and lifeless for us to live without outside help.

Q2. Do you think that climate change is a problem in the Antarctic and if so, do you think it is a problem we need to address as a country?

A2. Yes, climate change is causing the ice sheet to loose mass at an increasing rate and become even less stable (meaning large amounts of ice break off from the continent and into the oceans). The upshot being increasing sea levels  which impacts upon people, towns, and cities elsewhere on earth, particularly in low lying countries. In addition, with larger amounts of fresh water leaving Antarctica and entering the salty oceans, it can make the oceans currents behave differently which can then cause even more heating of the Earth’s atmosphere, and thus even more melting of the ice sheet, and so the problem gets worse and worse. The cause of this is not Antarctica itself, but the level of carbon dioxide that we are all pumping into the atmosphere. Yet given the scale of the problem, it will be change at the national and international government level that is the strongest weapon we have to reduce the impact.  That all said, we don’t need to wait for politicians to get their act together: we can all do our bit, we can all plant trees, which are the ultimate weapon against climate change and help restore the natural world — how about planting some in your garden?

Q3. How do you cope with 24 hour a day sunlight?

A3. It’s hard! Our body clocks are messed up by it. The sun is always high in the sky, making it very hard to sleep. And sleeping in a tent means we can’t escape it by pulling the curtains. The best we have are eye masks, which aren’t too comfortable.

Science at Halley Research Station

Katie Joy | 18 Dec 2019

We have written several posts about Halley research station, our home-from-home research base for the past two Antarctic field seasons — but what other science is being supported from Halley?

The station, located on the Brunt Ice Shelf at Lat. 75°34’5″S, Long. 25°30’30″W, has been occupied as a British base since 1957. The current version is called Halley VI and, with its futuristic space-station looking red and blue modules, is currently home to about 35 people in the summer who are supporting the station infrastructure and are assisting in the long-term science experiments running out of the station. Currently, because of potential issues surrounding the possible breakup of the Brunt Ice Shelf (see news stories here and here) the station is being operated in summer crew mode, and in the winter (from February onwards) all the staff leave Antarctica and return to the UK.

Current Science projects

Ozone hole monitoring: Measurements made at Halley that led to the discovery of a hole in the ozone layer in the 1980’s, leading to banning of CFC chemicals and international concern about the effects of ozone loss in the stratosphere (middle atmosphere). The equipment that made the discovery is still in use at Halley VI: called a Dobson spectrophotometer, is a device for measuring the amount of different wavelengths of ultraviolet (UV) radiation that reaches the ground (read more here) and used to determine ozone column density above our heads. Antarctica is a great place to make these measurements as there are few atmospheric pollutants which might absorb the specific wavelengths of light being measured. The station has a manual version of the spectrometer (see photo), a separate ozone monitoring station, and also recently has installed a computerised Dobson spectrometer that can run in automated mode through the Antarctic sunset and sunrise around winter when the base is without a crew. This automation has been made possible by the introduction of a micro-turbine energy generator, which ensures that this 60 year experiment can continue to run and collect data to ensure scientists with a continuous record of Antarctic ozone layer variation.

BAS’s James Byrne taking a Dobson solar measurement in the Halley science lab. [Credit: Katie Joy]
Katie attempting to take a Dobson measurement (and thus contributing to a 60 year science experiment!), under careful instruction from James. (NB I have my “doing-science-must-focus-so-I-don’t-screw-it-up” face on). [Credit: James Byrne]

Climate change monitoring, atmospheric and daily weather observations: Understanding how the climate is changing through time is a key science priority for the British Antarctic Survey. Every day the researchers here launch a weather balloon to measure the temperature of the atmospheric column, a record going back over 30 years which suggests that the atmosphere has been warming year on year up to 8 km in height above the ice surface. Scientists also measure the chemistry (trace gases and aerosol) of the Antarctic air using a special clean air sector laboratory (the lab is located in a position where aircraft cannot fly above it and no one can drive a mechanical vehicle like a skidoo in its vicinity — as such people Nordic ski or hike out to visit the site). Other atmospheric monitoring experiments to understand global high altitude wind (gravity wave) propagation, lightning strikes, and high altitude (87 km) temperature measurements all complete a suite of instruments that are setup or are being set up to run automated throughout the Antarctic summer and winter seasons to understand Earth’s atmosphere. In addition to these high altitude and long term climate records, daily weather (temperature, dewpoint, wind speed, cloud coverage, cloud type) is recorded and is also used for helping out logistical planning for aircraft movement around the area.

Space weather observations: Space weather is the term used when energetic particles ejected from the Sun interact with the Earth’s protective magnetic field (known as its magnetosphere). Often this interaction manifests itself as aurora at the northern and southern poles (also known as the southern and northern lights). An all-sky optical camera and, in the future, a new camera system will be able to monitor changes in local aurora conditions at Halley to determine the effects of ionisation in the upper atmosphere. This ionisation can also alter Earth’s magnetic field itself, and a series of magnetometers run at Halley to monitor these changes. Together this knowledge helps to understand the potential electromagnetic risks to orbiting satellites and on Earth electrical-based infrastructure, as well as helping unravel the fundamental science of how the Earth interacts with its space environment.

Brunt Ice Shelf movement: The ice under our feet at Halley is about 150 m thick. The station is slowly drifting towards the Weddell sea as the Ice Shelf propagates off the continent heading in a north-westerly direction. The Brunt Ice Shelf is continually in a cycle of growth and then break-up when large parts of the Ice Shelf edge carve and break off into the sea. At the moment there are two very large cracks opening up to the north (the Hallowe’en crack) and to the west (Chasm 1 crack) of the station. The development of these cracks and the movement of the Brunt Ice Shelf is being carefully monitored using high spatial resolution GPS stations and radar stations that are distributed around several sites on the Brunt. As and when, the Chasm 1 crack finally breaks the Ice Shelf in two, BAS will be a unique position to monitor the carving event and watch how the remaining Brunt Ice Shelf under Halley station responds to the change.

Brunt Ice Shelf showing locations of Halley VI base, Hallowe’en crack and Chasm I crack. [Credit: BAS]

Update from 218

Romain Tartese | 18 Dec 2019

Hi there, a few words from 218 — which is the British Antarctic Survey name for the depot site where we have been with Taff for a few days now. A few flights are still needed to bring south some more fuel and finish moving us and some kit to 119 — the site where the boys are about 100 km East, and where we want to deploy the metal detector arrays (in addition to flying Katie down from Halley). I have heard that they have found a few meteorites on the surface there yesterday — well done guys!

Weather has been mostly sunny at 218 except on Monday, so we have been exploring the surroundings a bit with Taff, going back to some ice fields Katie and Julie reconned last year. We believe we have found a few small meteorites, in the ice field closest to where we are camping. 🙂 Unfortunately we had snow a couple of nights ago, so the blue ice fields we drove to yesterday were covered by a fine layer of snow, making spotting meteorites impossible. But nevermind, driving around this amazing landscape was fabulous!

Short break for weather observations. [Credit: R. Tartese]