Then we head into the “hangar” to prep the balloon (plastic balloon, in warmer months we use rubber). The balloons are filled with helium and are clipped to a set amount of weight so we know that we will get consistent rise speeds and burst altitudes. Since the plastic balloons don’t expand, most of it left empty so when it get’s to high altitude at low pressure, the helium has space to expand into.

Then after some final preparation of the ozonsonde package which may include some heating elements to keep the pump warm and getting the battery ready, we are ready to launch!

Notice the bit of sunlight on the side of my face!

The main station and sunrise. This photo was actually taken a day before “official” sunrise. In actuality, the sun takes a several days to rise.

On station, we have begun the large list of tasks posted by our station manager which mostly involve shoveling out buildings that have been dormant for the winter, and performing deep cleans of bathrooms, hallways, and work areas. I’ve decided that I have spent enough time inside so I volunteered for a few shoveling tasks namely the cargo office, cargo DNF (the building that houses cargo waiting to be sent out or received that can’t be frozen), and a summer camp Jamesway tent. The FEMC (Facilities Engineering Maintenance and Construction) crew is probably the busiest group with the station opening work as they have to get fuel to all the buildings and start heating them up so they are ready when the summer folks arrive. Our heavy equipment operators are busy as well removing snow and beginning to smooth out the skiway for the first flights. They have had a little bit of trouble due to the cold temperatures because they cannot operate the bulldozers under certain temps.

The BIF (Balloon Inflation Facility) is just below the Sun. To half cylinder shaped buildings to the left are the Jamesways that are being dug out and warmed up for the summer crew.

At ARO, I’m just finishing up inventory to figure out what needs to be shipped down during the summer. It is mostly unchanged from last year because we haven’t had many problems with the instruments this year so there will probably just be a few items to alert people back at ESRL in Boulder, Colorado about. We are also at our intensive ozonesonde launching period where we are launching every 2-3 days as opposed to our normal one per week. It’s been rather unexciting in the depletion department this year. It seems that the polar vortex may not be all that well defined as some years with very low ozone levels. A description of the process of the annual ozone layer destruction over Antarctica can be read in my previous post, “The Ozone Hole: It’s Still There!” Once the sun is a little higher in the sky, we will be able to resume daily measurements with the Dobson Spectrophotometer (measures total column ozone through the atmosphere).

The solar instruments have also been placed back on the roof and are collecting data again. Initially they were having trouble with the -90F temperatures, but we have seemed to iron out the problems and they are now tracking the sun well. For an overview of the solar instruments, see the previous post, “As Sunset Approaches, Let’s Talk Solar Radiation”.

The roof of ARO and various solar instruments.

The next thing that is on tap for myself is organizing all of the flask samples that have been taken over the winter and getting them ready to ship out in the summer. Mostly that just involves writing up the paperwork so it’s ready to go for my replacement (yay paperwork!). Oh, and packing. The thing I look forward to least is also on the agenda. I will need to find boxes to ship home all the things that have kept me entertained here such as my Playstation 3 and movies. As well as excess clothing that I don’t want to travel with.

As I mentioned in “The Ozone Hole: It’s Still There!”, I will be posting an ozonesonde launch with the plastic balloons that we use. Don’t worry, I haven’t forgot! I have it videotaped and will get it posted soon!

Here are some more nice pictures during the last month or so:

The Moon and Venus. The were the last two visible objects in the sky as the sun was closer to coming above the horizon.

ARO from halfway between the station and ARO

The Moon over the Clean Air Sector, directly opposite of the rising Sun.

Nice reflection off the corner of ARO

The Moon about to set out over SPT (South Pole Telescope)

The atmosphere has four main layers which are the troposphere (the lowest layer in which most weather occurs), the stratosphere, mesosphere, and thermosphere. There is some ozone in the troposphere, but it is a very small amount and is produced by the reaction of pollution and ultraviolet (UV) light. Most of the ozone in the atmosphere is located in the stratosphere, hence the name the “ozone layer”. The ozone layer is important because it filters out some harmful UV radiation. CFCs eventually make it into the stratosphere and mix in with the ozone molecules. The CFCs don’t do their damage until they react with UV radiation which breaks the bond of the chlorine or bromine atom apart from the rest of the CFC molecule. Chlorine and bromine are highly reactive with ozone (a molecule consisting of 3 oxygen atoms) which then breaks the ozone apart becoming a ClO and O2 (regular breathable oxygen). The creation of ozone in the stratosphere is from the interaction of UV radiation with an O2 molecule. It splits the O2 creating two single oxygen atoms which then react with O2 creating O3 (ozone).

Example of the CFC/Ozone destruction cycle from NOAA’s ESRL website

These appear to be processes that could take place all over the world so why is the ozone hole unique to the Antarctic region? There are two main factors that enable a hole in the ozone layer to form over Antarctica: the polar stratospheric vortex and polar stratospheric clouds. Antarctica’s extreme cold temperatures allow for these polar stratospheric clouds to form. The clouds enhance CFC/ozone reaction causing the destruction of ozone to become very effective. The polar stratospheric vortex forms every winter over the Antarctic continent and keeps the air from interacting outside of the vortex. So basically ozone from outside the vortex is unable to flow in and replenish during this time. That is when we see the lowest ozone values. As temperatures warm through the summer, the polar stratospheric vortex begins to break up, polar stratospheric clouds disappear, and the air mixes back into the Antarctic stratosphere replenishing the ozone layer. The filling in of the ozone hole causes a decrease in ozone worldwide which how it becomes a worldwide issue. The ozone hole hasn’t proved to be decreasing yet but the fact that the harmful CFCs look to be working their way out of the atmosphere is encouraging and we look for the hole to begin decreasing in decades to come.

So right now we are at the point where the sun is getting just high enough (still well below the horizon) that its rays are beginning to hit the stratosphere breaking down the CFCs that are up there. At the Atmospheric Research Observatory (ARO) we measure ozone in three different ways. One is with a surface analyzer that gives us a baseline level of tropospheric ozone, and the other two include the Dobson Spectrophotometer and launching ozonesondes which both give us an idea of stratospheric ozone.

Ozone surface analyzers

The Dobson Spectrophotometer. During the winter, observations are only available when the moon is up. Bad weather and poor visibility can hamper opportunities thus making balloon launches extremely important (especially so this winter it seems!).

For most of the year we launch one balloon a week but as the ozone hole forms we start launching two to three times a week. The idea is that we increase the resolution of the data so that we can see the peak of the ozone depletion. The balloons are great because they give us a complete profile of the ozone all the way up to 30-35 kilometers high.

In the winter we launch plastic balloons. The rubber balloons don’t get high enough due to the cold air. (ideally we like to get up to 28-30km).

When there is enough light outside for video, I will take you through an entire launch sequence explaining how we prep the sonde, prep the balloon, launch the balloon and show the software that gives us the profile of the data. We can even compare what a normal “healthy” layer looks like prior to the hole forming to the hole itself.

The Final Flight: February 14th, at 2:30am New Zealand time.

We have just barely over two weeks until the sun sets and temperatures are already starting to drop quickly. The day of station closing, temperatures were around -40F. Today it is the coldest since I’ve been here at -63F, and tomorrow it’s suppose to bottom out at almost -70F. It’s amazing how quickly it drops when that sun gets low. The cold temperatures also make everyday things difficult to deal with. We had an emergency response drill today that took place outside and I volunteer on the fire team. You have to be really conscious about your gear because the SCBA (Self Contained Breathing Apparatus) hoses start to freeze and can crack easily. A fire fighter isn’t much good without a working SCBA. Frostbite is a big concern as well. The fire gear gloves and boots are not insulated for cold and do a very poor job of keeping your fingers and toes warm.

South Pole Station from ARO.

As for the science here at ARO (Atmospheric Research Observatory), not too much has changed. I’m still coming out here every day to check to make sure everything us running as it should be and taking air samples in flasks every week. One thing that is starting to change is our ability to do Dobson observations. The Dobson Spectrophotometer is an instrument that uses sunlight to measure total column ozone in the atmosphere. When the sun is this low on the horizon, there is a lot of stray refracted light that affects the measurements and can give us bad results. You may ask, “How do you take measurements in the winter?” Well this is done by using the reflected sunlight off of the moon. So we are able to take sporadic observations to coincide with our balloon flights through the winter. The solar radiation instruments on the roof will be coming down soon after sunset as well, which will be a small project for us. Here is a brief description of the solar radiation measurements we have at ARO and why we are measuring it.

Incoming solar radiation is the backbone of what drives our climate. Changes in the amount of radiation reaching the earth from the sun can be the difference between being in an ice age or not. It is important for us to know how much radiation is a) reaching the surface, b) what type of radiation it is (wavelength), and c) how much is bouncing back off the surface. This is what’s called the “Radiation Budget” in its most basic form. The “Radiation Budget” involves many other processes but the pictures and descriptions below show how we break down the “Radiation Budget” into its basic components at ARO.

The Solar Tracking NIP (Normal Incidence Pyroheliometer)

The NIP tracks the sun in all 360 degrees. It measures direct incoming solar radiation of specific wavelengths.

Diffuse Pyranometer

The diffuse pyranometer blocks out the incoming direct solar radiation and measures any radiation that is getting reflected and refracted from substances in the atmosphere (or any radiation taking an indirect path to the surface).

Pyranometers

These pyranometers detect all incoming solar radiation both direct and indirect. The two outer ones have filters on them to divide it up into shortwave (UV) and longwave (infrared) radiation.

Albedo Instruments

The “Albedo Rack” is basically exactly the same as the pyranometers except that they are turned upside down. They then measure the amount of solar radiation that is reflected off of the earth’s surface. Roughness and color play a role in Albedo meaning that a smooth surface is going to reflect more than a rough surface, and a white surface is going to reflect more than a black surface.. Therefore, it is important not to disturb the snow under these instruments because we want the natural state of the surface. In addition to reflected radiation, it monitors infrared radiation emitted by the earth.

A more complex version of the “Radiation Budget” or “Energy Balance” pulled from the IPCC Fourth Assessment Report.

As you can see, in the above figure, there is a lot that really goes into the “Radiation Budget” and it is a very complex system. When the solar energy comes into the atmosphere, it can take a variety of paths. It can get interrupted by clouds, gases, aerosols and other substances. Two of these processes in the system we observe at ARO as well such as Aerosols, and Greenhouse Gases which I will talk about in a later post.

Hopefully this explains a little bit what’s behind the solar radiation observations that we take at ARO. The South Pole and Mauna Loa have the longest continuous running solar radiation observations of this kind. It’s extremely important that we understand what happens to solar radiation as it passes through the atmosphere and hits the earth’s surface if we want to gain a good understanding of how earth’s climate works. It is even more important as we try to predict future climates.

The entrance to the ARO (Atmospheric Research Observatory).

Those daily tasks that I mentioned mostly just involve going through all the equipment in the station and making sure that it is running correctly. Some instruments need daily adjusting to keep them acquiring good data. Others operate on their own pretty well (look for future posts to go more in depth on what exactly these instruments are and what they measure). Throw in setting up some new instruments, launching two ozonesondes (ozone measuring weather balloons) a week and flask sampling (capturing air to sample in flasks), it keeps one pretty busy especially when not really experienced with much of it.

Help has now arrived as Mark VanderRiet arrived last week and Lana Cohen has arrived today. With a couple of weeks under my belt, I am starting to feel much more comfortable on the day-to-day operations and things seem to be running smoothly for the most part. We’ve shipped most of the sampled air flasks that have accumulated over the winter back to their project locations (due to the fact that there are no flights to ship them during the winter season), and are getting ready to receive the shipment of new flasks and other supplies for the up coming year.

As for life on station, it is pretty incredible how we are living down here if you consider what a remote location this is. The room I was assigned is plenty big for my needs and is pretty comparable to the size of room that I had when I was on the NOAA Ship Fairweather. The recreation schedule here is full. Every night of the week there is something going on in the gym (volleyball seems to be the most popular), and there is a great selection of movies and TV shows in the store. The observatory is a great place to hang out in the evenings too if you want to relax and watch a movie. It also gives you a chance to shoot some evening Dobsons too (the Dobson is an ozone measuring instrument)! And by the way, winning bingo twice in one night is not a good way to make friends around here.

Once things settle down, I’m excited to show you all what kind of equipment we have at the Atmospheric Research Observatory, and what it measures. Hopefully I can get into some of the other projects that are going on down here at the Pole as well. I would think I’ll have time, I’m here for the long haul!