Dec 4 – Friday
On our third full day at WAIS, Mark and I flew for the second day in a row, this time to Thurston Island AWS. Our plan was to go to both Evans Knoll AWS and Thurston Island AWS, and when going over the weather with the Otter crew before departure, it looked like Evans Knoll had better weather than Thurston Island. We decided to check Evans Knoll first.
With us came John Stone, the aforementioned geologist, and Paul Koubek, a mountaineer. Paul came along because these AWS are on islands covered in ice, and with that comes crevassing as the ice spreads down the slopes of the islands. We wanted to take the extra precaution and have an expert with us to make sure we didn’t walk into a crevasse field. Spoiler alert: We didn’t encounter any crevasses while walking!
John Stone and Paul Koubek are in the background.
As we approached Evans Knoll, cloud cover dominated the area. This led to “flat light” in which the surface features and definitions are very difficult to discern. This made it unsafe for us to land, as the pilots could not distinguish the slopes of the island and therefore find a safe place to land. After circling the island several times they decided we shouldn’t land, so we headed to Thurston Island.
I had it in my head that the weather at Thurston would be similar to Evans Knoll, and we would shortly be heading back to WAIS. I’m very glad that I was mistaken; it was mostly sunny at Thurston, and we circled the island a couple times and then went in for a landing. We taxied close to the nunatak (area of exposed rock in an ice field) where our AWS is located, then Paul got out and checked the surface to make sure it was safe. Sure enough, it was, so we lugged our equipment up the small hill.
Paul checked for crevasses along the path from the plane to the AWS (upper right).
I was not expecting this sight to be as pretty as it was. For starters, the weather was pleasant: temperatures around 20 F and light and variable winds, with sunny skies. Also, being on the highest point of the island (I think) allowed for great views of the area. Setting aside the picturesque scene, Mark and I got to work repairing the station. This site experiences very high winds on occasion (luckily not today!), and because of that the wind monitor and the relative humidity sensor were damaged.
Thurston Island AWS upon arrival.
I climbed the tower to replace the nose cone and propeller on the wind monitor. We then removed the old relative humidity sensor and installed a new one. After adjusting the program on the data logger to accommodate the new RH sensor and verifying all data output looked good, we called our work complete and got ready to leave.
Thurston Island AWS after our work was complete.
While Mark and I were working on our AWS, John and Paul were walking around the exposed rock regions, and John collected some rock samples. We were happy to have John come along and get some use out of this trip!
John Stone took this picture of us as we were getting ready to leave. Note how you can see the AWS on the right.
Our flight back to WAIS was a lengthy one: 467 nautical miles, to be exact. It took us about 3.5 hours, and it was the longest Twin Otter flight I had been on. We were also flying relatively high up (~16,000 feet). At this elevation, the lack of oxygen is noticeable. Mark asked the pilots about this after we landed, and they said they flew so high to catch the tail winds and get good fuel efficiency so we wouldn’t have to stop at a fuel cache on the way back to WAIS. No complaints on my end! I was able to read a couple chapters in my book and doze off a couple times. All in all, it was a good day for AWS fieldwork.
Dec 3 – Thursday
Mark and I had our first station visit out of WAIS today, Thursday 3 December, going to Byrd AWS to raise the station.
We hadn’t planned on going to Byrd. In our first scheduling meeting with the Twin Otter pilots, we told them we wanted to aim to go to four AWS for our first two flights: Thurston Island and Evans Knoll for one flight, and Erin and Brianna for another flight. The other science group, John and Joel the geologists, are also hoping to use the Otter to put in their camp at Parrit Hills. Today, the weather was poor at all of the listed locations, so we thought there wasn’t going to be any flying.
Mark had the great idea to ask if the Otter pilots, Troy and John, if we could try going to Byrd AWS. It is located near WAIS (only about a 40 minute flight away), and it’s collocated with Byrd Camp, where 4 people are currently staying, trying to dig out the camp. They would be able to provide ground weather observations for us, ensuring it would be safe to fly.
Lo and behold, the weather was excellent at Byrd, and we got the go ahead to fly there! We started getting our equipment ready, and some WAIS camp staff gathered up some boxes of supplies to send to the Byrd Camp staff, including mail.
We used a snowmobile to bring most of our cargo over to the Twin Otter before departing.
We departed WAIS around 9:30 am and got to Byrd camp around 10 am so we could first drop off the extra supplies. The Byrdies (I’ve decided to call them that… I haven’t heard anyone else refer to them as such) were really excited to see us, and even more excited to get their presents. I recognized them from when we were in McMurdo, as they were waiting for their chance to get to Byrd Camp.
Once we all exchanged pleasantries and said bye to the Byrdies, we taxied in the Otter over to Byrd AWS. It is within eyeshot of Byrd Camp.
The station raise went very smoothly. There were hardly any hiccups. Troy and John were very kind to help us with digging, handing up instruments and/or tools, and making the work proceed efficiently. The station now stands pretty tall and won’t be getting buried any time soon!
Byrd AWS before the raise.
Byrd AWS after the raise.
We had a very good first experience with doing AWS work out of WAIS, and we’re only on our second full day here. Hopefully there are more days like this to come during our (planned) short stay at WAIS!
For the cargo update, on the night of December 2 we got our case of the rest of our equipment, including radios and harnesses. Now all we’re waiting on are the extra power systems and tower sections for the station installs and replacements. Those might be coming tonight!
Dec 1 – Tuesday
We arrived at WAIS today! Just in the nick of time, as we had set this day as our cut-off date to get out to WAIS. If we didn’t make it today, we figured it wouldn’t be worth our time to leave McMurdo to come to WAIS, given our off-ice departure date is 14 December. There was still plenty of work that we could have done in McMurdo, but now that we were able to get to WAIS, hopefully weather will cooperate and we can knock off some station visits here!
Mark and I left McMurdo at 8:15 am, boarding an LC-130, WAIS-bound. Overall, it was a pretty uneventful flight and we reached WAIS at 11:50 am. It was a little windy when we got off the plane but not too windy, and temperatures were around -4F. There were 5 passengers total on this flight: myself, Mark, Paul (mountaineer), and John and Joel from another science project. The rest of the flight weight was taken up by cargo. I think there was approximately 12,000 pounds of cargo allowed in the plane, so you can get an idea of how much cargo was on the plane! This included 2 snowmobiles for John and Joel.
The LC-130 at WAIS, after we departed the plane.
We got off the plane, took our hand-carry bags and first went to the galley where we were told to meet. We were greeted by people who were anxious to get on the plane back to McMurdo. They had been waiting at WAIS for this flight for almost a week, and I could tell that they were ready to go. I’m glad they were finally able to get out!
Eventually we got our in-brief and got acquainted with the camp. The camp is essentially organized in lines. If looking at the camp from a bird’s eye view, the lines are oriented vertically. The furthest left line is made up of work tents; this includes the galley and wash module, the medical tent, two science tents, the mechanical tent, the Twin Otter and fuel station and a couple others. All of the work tents are heated. At the bottom of this line is “tent city,” where each WAIS resident has their own tent to sleep in. The next line to the right is the line of outhouses, to go to the bathroom. The remaining 4 lines to the right are cargo lines.
Aerial view of WAIS camp, taken from a Twin Otter.
An annotated aerial view of WAIS camp.
Mark and I are in one of the two science tents, and we have it to ourselves for the time that we will be at WAIS. There is plenty of space in the tent to allow for a few tables, used as desks for Mark and I and as a work bench, and even enough space for cots. Beth, the camp manager, offered that Mark and I could sleep in our work tent instead of setting up a tent. We decided to take her up on the offer. I know we’re not getting the “full” field camp experience, but since we only plan to be here for a little over week, we thought we might as well sleep in a heated tent on cots. Honestly, it’s quite luxurious.
We’re getting things set up already, and even though we don’t have all of our cargo here (it’s a long story), we do have enough to do work on a couple AWS right now. We plan to leave WAIS between December 8 and 10, so hopefully our cargo can come soon so we can do as much work as possible while we’re here!
Well that’s all for now. I’ll be writing more updates as they come.
In my haste to update you all on our WAIS status, I neglected to include that we were able to fly Twin Otter to Elaine AWS, on the southern end of the Ross Ice Shelf, on Friday 27 November. We were able to do this after we got word that our WAIS flight for that day was cancelled. A huge thanks to the folks at fixed wing for setting this up for us!
The weather was great for a station raise at Elaine. For the entirety of our visit, the winds remained low and temperatures were around 10F.
Elaine AWS when we arrived. There was a lot of digging in store for us. In the background are the Transantarctic Mountains.
As the picture shows, Elaine obviously needed to be raised. There had also been an issue with the relative humidity sensor, which manifested itself as unusually steady observations. I’m willing to bet the reason for that problem was because the sensor was buried!
Mark and I had to dig down about 6 feet to get to the enclosure and free up all of the cables that we needed to loosen so we could raise the instrumentation on the new tower. The work was fairly slow-going, but the pilots were nice enough to help us out with some digging when they could.
After several hours, we had Elaine raised up and featuring a new relative humidity sensor. We took some pictures and then headed back to McMurdo. Not too shabby, considering we thought we were flying to WAIS early in the morning!
A taller Elaine AWS.
Mark and I remain in McMurdo for the Thanksgiving holiday weekend. On Thursday, our flight to WAIS boomeranged! We left McMurdo around 10 am, but when we reached WAIS, the weather was too poor to land. Our plane circled the camp for about 20 minutes, but eventually the pilots received word from people at the camp that the visibility was too low for our plane to land. We had to turn back and go to McMurdo.
Yesterday, we were again on the schedule to go to WAIS, but our flight was cancelled due to poor weather at WAIS.
This is a common theme for WAIS: poor weather and long delays.
While people worked in McMurdo on Thursday, Thanksgiving day, the town is pretty much closed for business this Saturday and Sunday. (Almost) everyone has these two days off, including the pilots. If there’s good weather at WAIS, we can’t take advantage of it this weekend. At least Mark and I can enjoy the Thanksgiving festivities in town!
We will surely be trying again on Monday. I’ll update you all when I can!
Earlier this week, on Monday 23 November, Mark and I took a helo “night flight” to Linda AWS to finish up the work we couldn’t get done during our first visit there 9 days prior. The helo schedule has been fairly busy as of late, so the best time that they could squeeze our flight in was at 7:30 pm that Monday night. Normally our helo flights don’t go much past 5 pm.
The night flights are much more relaxed than flying during the day. There are fewer flights to be done and fewer helo personnel. Mark and I took an A-Star (smaller of the two helos) and flew to Linda AWS to check the pressure sensor, swap it if need be, install the new power system, and raise the enclosure on the tower.
When we arrived, we noticed that the hole that we made when we tried removing the power system in our first visit was completely filled in. Those strong winds created enough blowing snow to fill the hole, as if we have never tried. Luckily, the weather was much more pleasant this go-around. Temperatures were around 15F and winds didn’t get much above 10 mph. It’s so much easier to do field work when it isn’t windy!
Linda AWS when we arrived. The old power system is buried to the right of the station; the new one is visible.
Our first order of business was to check the Paroscientific pressure sensor because it was not reporting any values. We checked connections and did some diagnostics but could not correct the issue. We had to swap out the existing one for a Vaisala pressure sensor. We were able to get measurements to transmit with the Vaisala, so we plan to do some troubleshooting back in Madison with the seemingly faulty Paroscientific pressure sensor.
We dug out the existing power system, with the help of the helo pilot and connected the new one. Lastly we raised the enclosure, which involved reorganizing the long cables extending from the sensors on the tower. This, admittedly, took a little longer than expected. In the end, we finished our work at Linda and can check this AWS off the list for this field season.
Linda AWS when our work was completed.
In other news, Mark and I are on the schedule to go to WAIS tomorrow, Thursday 26 November (Thanksgiving). This departure date has changed many times, as weather and scheduling dictates. As I’m writing this, just a couple hours ago we thought we were going to depart on Friday, but we got an update saying the plan is to leave tomorrow.
We plan to be at WAIS until approximately December 10. While there, our internet availability will be limited to email, at best. As such, I will not be able to update you all with our work, real-time. I will be writing up equivalents to blog posts while we’re out there, so when we get back to McMurdo I can post those and you all can catch up on our adventures.
Cheers for now!
This past week has been a quiet one for Mark and I. But when it’s quiet for us, that usually means it’s hectic elsewhere.
There has been a storm parked over West Antarctica for the past several days now. A weather observer who will be going to West Antarctic Ice Sheet camp (WAIS) has been in correspondence with the folks who are already at the camp, and he says WAIS has been experiencing Condition 1 weather for the past 2 to 3 days! Here’s a recap of the 3 different “conditions” that the United States Antarctic Program classifies in Antarctica:
Severe Weather Condition I
- Winds greater than 55 knots sustained for one minute, or
- Visibility less than 100 feet sustained for one minute, or
- Wind chill greater than -100°F sustained for one minute.
Severe Weather Condition II
- Winds 48 to 55 knots sustained for one minute, or
- Visibility less than ¼ mile, but greater than or equal to 100 feet sustained for one minute, or
- Wind chill -75°F to -100°F sustained for one minute.
Weather Condition III
- Winds less than 48 knots, and
- Visibility greater than or equal to ¼ mile, and
- Wind chill temperature warmer than -75°F.
These categories are used primarily for work and travel purposes. If the weather is too harsh, it can be potentially deadly for someone to drive a truck out to the airfield. They are also an easy way to describe how harsh conditions have become. Also, one thing I find amusing is how extreme the weather needs to be just to go from Condition 3 (good weather) to Condition 2.
Antarctic infrared satellite composite image at 03 UTC on 19 November, created by the Antarctic Meteorological Research Center. Note all the clouds streaming over West Antarctica.
While weather was terrible at WAIS, it was also poor over the Ross Ice Shelf. Very windy conditions over the shelf and in McMurdo led to many flight cancellations, and the town was almost at a stand-still for a couple of days this past week; science groups like ours who were hoping to get either helicopter or Twin Otter flights were cancelled, and flights to and from Christchurch were cancelled.
Although staying in town may not be glamorous, it can be very helpful for our field work. It gives us time to reorganize tools and equipment and prepare cargo for future visits. One of our station visits to Harry AWS, from WAIS will involve swapping out the existing electronics and instruments with new ones. During this downtime, Mark and I were able to gather the new instruments and test them to make sure they were working properly. Now we can get them into the cargo system to be shipped to WAIS. We are now preparing for flights for next week by talking with the helo and Otter coordinators and letting them know what sites we would be able to visit so they can consider those when they make the daily schedules.
Given the bad weather at WAIS, it has delayed our group’s deployment out to the field camp. The Condition 1 weather has set the camp staff back a day or two, as they will now need to dig out from all of the accumulating and blowing snow they’ve received the past few days. They also need to re-prepare the airfield at the camp so planes can land there safely. Mark and I have received word that we will hopefully be going to WAIS before the Thanksgiving holiday (which is 28-29 November here, rather than actual Thanksgiving on the 26th), so we will just have to wait and see. In the meantime, we are trying to do as much work out of McMurdo as we can.
Mark and I escaped a close one a couple days ago. On Saturday, 14 November, we flew helo to Linda AWS, a site about 40 miles southeast of McMurdo. We planned to install a new power system, raise the station, and investigate some issues with the pressure sensor. Hardly anything went according to the plan that day.
We arrived at the AWS at about 9:30 am. We unloaded all of our cargo from the helo, then spent the next 20 minutes verifying that we could get communications through to both McMurdo and the helicopter. Each of us bring a VHF radio that we can use to call in to McMurdo (specifically “MacOps” or McMurdo Operations) to let them know we’ve landed, as well as request for any assistance, including letting them know that we want to be picked up. We also use the radio to communicate with the helo pilots who would come pick us up. We have one satellite phone as a backup to the radios. It works just like a regular phone, such that we can call pretty much anyone. We couldn’t get a direct connection to MacOps through the radios, so we had to test going through some repeaters. That didn’t work, so we used the phone to call in. Then we tried the radios again and were finally able to speak with MacOps. I’m glad we took the time to make sure the communications worked properly.
The weather when we landed wasn’t ideal. Temperatures were OK at around 8 F, but winds were at 21 mph and only increased throughout our visit.
Linda AWS when we arrived. You can sort of tell how windy it is by looking at the blowing snow at the surface.
Given the current height of the station, we decided not to raise it with another tower section. We decided to save the power system to install for last and work on the solar panel and the pressure sensor. The solar panel had come loose from its mount, so Mark climbed up and refastened it. The pressure hasn’t been transmitting, so I looked at the sensor to see if I could find any issues with it. I couldn’t, so I left it be, for further investigation.
Once we had finished these tasks, we noticed that the winds had increased, along with the blowing snow. Land features like White Island and Minna Bluff, which were clearly visible when we landed, were getting harder and harder to see. It was at this point (around 11:00 am) that we decided to call MacOps to request to be picked up.
Mark snapped a picture of me radio-ing in to MacOps.
MacOps said a helo wouldn’t be coming to pick us up for another hour or so. In the mean time, we tried to dig out the existing power system. With the wind and blowing snow, that proved to be difficult, so we didn’t fully dig it out.
We built a wind wall with our equipment to block the wind; the power system that we didn’t install came in handy here, as it is a big, bulky box. Eventually we were both sitting there, listening to the winds howl, watching the blowing snow accumulate on our pants and jackets, and waiting for the approaching helo pilot to radio to us, telling us he was close. The horizon was impossible to see, but overhead we could see blue sky. This was encouraging, as it meant the helo pilot could most likely see us and be able to land. If it was an overcast day, the helo may not have been able to land (due to poor surface definition) and we would have had to wait until the weather cleared, perhaps meaning we would need to camp overnight. Our chances of being picked up were also higher because the same pilot that dropped us off was picking us up; he had the exact coordinates of our location and knew what to look for.
Me hiding behind our wind wall. The winds were blowing at a sustained 30 mph!
After about an hour and 15 minutes of waiting, we finally were contacted by the helo pilot that he was 5 minutes out. What a great feeling that was to hear his voice! When he landed, he kept the blades spinning (a “hot landing”) so we packed up our gear and got out of there as soon as possible.
Linda AWS after our visit, taken from the helicopter. This is looking into the wind, giving a good idea of how the horizon definition decreased dramatically. (The black box at the base on the right is the new power system, which we did not install, but rather just left at the site.)
Here are the observations recorded from Linda AWS during our visit. The time of 203000 UTC corresponds to 9:30 am McMurdo time.
STATION JULDATE TIME T(C) P(MB) SPD(M/S) DIR(DEG) RH(%)
Linda 2015317 203000 -12.6 NaN 9.7 206 58
Linda 2015317 204000 -12.7 NaN 11.1 199 60
Linda 2015317 205000 -13.1 NaN 11.4 209 66
Linda 2015317 210000 -13.4 NaN 10.7 212 67
Linda 2015317 211000 -14.5 NaN 11.0 206 72
Linda 2015317 212000 -15.4 NaN 12.3 201 73
Linda 2015317 221000 -17.0 NaN 11.5 202 74
Linda 2015317 222000 -17.2 NaN 12.9 203 74
Linda 2015317 223000 -17.6 NaN 13.6 196 73
Linda 2015317 224000 -17.8 NaN 14.0 195 74
Linda 2015317 225000 -17.9 NaN 14.3 193 75
Linda 2015317 230000 -17.9 NaN 14.3 190 75
Linda 2015317 231000 -17.8 NaN 13.8 188 76
Linda 2015317 232000 -17.7 NaN 14.9 186 75
Linda 2015317 233000 -17.6 NaN 14.0 185 76
It’s a visit like this that reaffirms my appreciation for the effectiveness of MacOps and Helo Operations. That Saturday may not seem like a huge deal to them (probably because everything on their end went relatively smoothly, overall) but their actions allowed me to sleep in a warm bed that night, and for that, I am very grateful.
Mark and I have hit a pretty good string of flying since I last updated you all. Since White Island AWS, we have flown to 5 other AWS: Cape Hallet (for the second time), Emilia, Vito, Ferrell and Margaret. Some of these AWS need to be visited again, however, so not all of the work is done yet. In this post I’ll give a brief summary of each visit.
On Friday, 6 November, we flew with 3 boondogglers to Cape Hallett AWS. (For those who don’t know, boondogglers are people who come along on our flights to either help us do some work or just to enjoy the trip. Most boondogglers are those who rarely get to go out of town, so any flight for them is a treat. These boondogglers got spoiled because they got to go to such a beautiful place!) As I mentioned in a previous post, we needed to go back to Cape Hallett to update the program that was loaded on the data logger. In our testing in the lab, we also used a new, improved modem, so we installed that one at Cape Hallett. Everything is running properly now!
Aerial view of Cape Hallett. This time the pilots took a slightly different route than the first. Our AWS is on the flat piece of black land on the left and near the ice edge. Most of the penguins are on the light brown land.
Due to ice conditions, we had to land the plane a fair walk from the AWS. From left to right: Shandra, Cindy, Kelsey (pilot), Laura, and Rob (pilot).
The penguins of Cape Hallett. There were noticeably more penguins on this visit than our first a week and a half before.
Me and the fully-functioning Cape Hallett AWS.
The next day, 7 November, we flew to Emilia and Vito AWS via Twin Otter. These AWS are on the Ross Ice Shelf, fairly close to each other, and only about an hour from McMurdo. The trip was relatively quick. At Emilia, we swapped out aerovanes. After that we flew to Vito and power cycled it because it hadn’t been transmitting. That didn’t work, so we removed the electronics box to bring back to the lab so we could troubleshoot.
Emilia AWS with a new anemometer on top.
Vito AWS when we arrived.
Vito AWS after we pulled the electronics.
The next working day, Monday 9 November, we flew helo to Ferrell AWS. Here we raised the station by adding a new tower section and moving most of the instrumentation higher up on the tower. We did not bring a new data card to swap out from the data logger (which stores all of the data collected at the station [there isn’t enough bandwidth to transmit it all via Argos]) so we will need to swing by the AWS later in the season to do that.
Ferrell AWS before we made it taller.
There’s Mark on the tower, installing the solar panel mount.
Ferrell AWS after our work there was done.
Flying to Ferrell had marked our 4th day of flying in 5 work days. It is excellent to get out in the field that often, but also tiring. We had the next two days off to rest and regroup.
Yesterday, Thursday 12 November, we flew Twin Otter to Margaret AWS. Margaret is on the opposite side of the Ross Ice Shelf from McMurdo and is about a 2 and a half hour flight. The weather is notoriously poor in that area, so we were thrilled to get the opportunity to fly.
Like Ferrell, Margaret needed to be raised. Due to the raise, we either needed to dig up the existing batteries that we buried in the snow or install a new power system. The battery cables in the existing system would not extend far enough for the raise, and we didn’t have any extensions.
We first added a new tower section, then decided to try to dig out the existing batteries. It turns out they were about 8 feet below snow surface, and there were 3 boxes to retrieve. That was way too much work than we could afford to do, in terms of time and energy. We installed the new power system, and everything worked like a charm.
Margaret AWS when we arrived.
Margaret AWS after we raised it and installed a new power system (black box on the bottom).
Fourth times a charm.
Mark and I visited White Island AWS yesterday, 4 November, to do a station inspection. It was our fourth day of being on the helicopter (helo) schedule to visit the site. (For the record, helo flights are much easier to plan around compared to Twin Otter because helo flights don’t usually take up an entire day.) The first two days, we were canceled due to weather. The third day, 3 November, it was windy in McMurdo but it appeared okay at White Island. We departed McMurdo on the helo, but as we approached White Island we saw a low cloud/fog bank creeping over the tallest part of the island, Mt Heine, where our AWS is situated. The helos are unable to fly through clouds such as that, for obvious safety reasons, so we had to turn back. That cloud bank may have been the beginning of some poor weather in McMurdo, as the rest of the day was quite windy (15-20 mph, air temp around -5F, wind chills down to -30F) in town with a lot of blowing and drifting snow.
Yesterday was the fourth time we tried, and we got there. Our goal was to inspect the station to make sure instruments and cables looked fine. One point of concern for us was the state of the wind monitor. White Island experiences strong winds (even possibly the highest wind speed ever recorded at a UW AWS! More on that later….), and we don’t have a high wind speed sensor installed. We just have our standard RM Young wind monitor.
On our way to White Island, we dropped of one passenger, an electrical technician, at Black Island (the two islands are essentially right next to each other and about a 15 minute flight from McMurdo).
The manned station at Black Island. We dropped off the man in Big Red on the left.
The winds were quite strong at Black Island (~50 mph) as they usually are, but our AWS at White Island was recording winds at only~10 mph.
I have never been to Black Island, and consequently never seen the area between the two islands. It looked pretty cool, especially with the blue ice.
The view on our way from Black Island to White Island. Black island is pictured in the foreground, with Mt Discovery in the background.
A blue ice field. There is no net snow accumulation, mostly due to the high winds, so the ice is exposed.
We approached White Island and negotiated a good spot to land the helo. Once safely on the ground, Mark and I grabbed our bags and made the short hike up to the station.
The winds were fairly calm when we first arrived at the AWS, which was a little surprising considering how strong they were at Black Island. Mark and I shrugged it off and started inspecting the station. We checked the instruments to make sure nothing was broken, checked the cabling to make sure it was still secured. In particular, we looked for damage to the wind monitor at the top of the station.
White Island AWS, with Mark on the left for scale.
Back in July of this year, a high wind speed affected the area surrounding White Island. For about half a day, wind speeds at White Island AWS were around 60 m/s (134 mph!). The wind speed peaked at 62.7 m/s (140.3 mph) which, if verified, would set the record for highest wind speed ever recorded at one of our AWS!
With good reason, we were curious to see the state of the wind monitor. In most cases, we would install a high wind speed system at a site that recorded such wind speeds. Since White Island AWS was only installed 4 years ago, and it’s our first AWS on this island, we weren’t sure how high the wind speeds were. We think we’re getting the idea now.
Speaking of high winds, after about 10 minutes of Mark and I checking the AWS, the winds started to pick up. There was actually a time when the wind went from calm, to a sustained wind of about 20 mph for 30 seconds, then calm again. It was very strange. After a couple minutes of calm winds, it picked up again and remained gusty. For the last 20-30 minutes of our visit, winds were measuring a sustained wind speed of around 30 mph with gusts around 40 mph. Here are the obs, recorded from White Island AWS and posted on our website, during our visit:
STATION JULDATE TIME T(C) P(MB) SPD(M/S) DIR(DEG)
White Island 2015308 000000 -24.5 895.1 3.3 191
White Island 2015308 001000 -25.8 894.5 8.7 180
White Island 2015308 002000 -26.5 894.5 12.3 191
White Island 2015308 004000 -26.7 894.0 12.3 192
White Island 2015308 005000 -26.6 894.1 13.2 193
The time is listed in UTC, and since NZDT is 13 hours ahead of UTC, the first observation listed corresponds to 1 pm on Julian day 308, or 4 November. We landed at 12:55 pm, so it just about matches up with our ground time. We departed at 1:45 pm. Also, one thing to note about the observations is that there is an observation missing at 003000, or 1:30 pm NZDT. This is because we had powered down the AWS to troubleshoot some issues with the data card on board the data logger.
As a fun fact, at 1:40 pm the air temperature was -16.1 F, so with a recorded wind speed of 27.5 mph the wind chill was -46.7 F! That’s almost as cold as I experienced at the South Pole last season!
After Mark and I got back into town, we changed gears a bit and did some final preparations for our presentation at the Crary Wednesday Science Lecture. Crary is the building in which our group and many other science groups work. Every Wednesday, a person or group will give a talk about their work or research they’re doing. Mark and I talked about “Telling Antarctic Meteorology Stories: From Observations to Modeling.” For the first half of the presentation, I spoke about the history of our AWS program and touched on some research that has been done with AWS data. Then Mark talked about how observations can be used to improve weather models and likewise spoke about some research using such models. It turned out very well!
Dave talking during the Crary Wednesday Science Lecture.
Mark talking at the Crary Wednesday Science Lecture.