Monthly Archives: November 2012

wireless data connections!

We study many streams in the Dry Valleys. These streams are located far enough apart to justify the use of helicopters to get back and forth. Our streams gages consist of very expensive science equipment, which helps us measure stream dynamics, such as water height, water temperature, and specific conductivity. Given the distance between sites, the very expensive (and delicate!) science gear, and the extreme conditions of Antarctica – monitoring streams in the Dry Valleys costs a lot of money!

When something breaks at a gage site, it is always best to know ahead of time. Prior knowledge of field failures saves money in the long run, because we’d only need one helicopter trip to fix the problem, rather than two (one to discover the problem, and the other to go back and fix it). Turns our, helicopters are not the cheapest mode of transportation.

To help us get an idea of what is happening at sites very far away, some gages can radio-transmit real-time data via a series of radio and satellite connections to a computer we can easily access.  So, before we visit a site, we can look at the data to see if something looks funky. Usually funky or unusual data means a mechanical or electrical problem, which requiring maintenance.

Today, Chris and I worked to set up a new radio repeater on Mt Loke. Radio repeaters, take an incoming radio signal and repeat it so it can be received at some location far away. Radios only work by line-of-sight. So if you and your pal each have a walkie-talkie radio, then generally speaking, if you can see one another – you can talk to one another. At our main camp, F6, we certainly cannot see most of the stream gages in the Valleys. So, we use a series of radio repeaters to transmit real-time data, such that we can see it at F6.

Here are a few photos from our trip. Lucky for us, radio repeaters are located up in the mountains with a great view (line-of-sight) of places all through the valley.

 

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Measuring discharge with “rating curves” in Antarctica

The temperatures have been rising lately. Warmer weather and intense solar radiation combine to melt glacial ice and snow patches. The melt water then runs down-gradient forming streams! The stream team monitors these streams to account for how much water is flowing, where it is going, and when it is going there.  A major responsibility of the Stream Team is measuring stream discharge at many sites throughout the Dry Valleys.

A stream’s discharge is the volume of water passing a cross section of stream per unit time. Discharge is always expressed as volume/time (e.g. litres per second, cubic feet per second, cubic meters per second, etc.). Instead of a river, let’s think about your kitchen faucet. If you turn the faucet on and allow water to pour into a measuring cup for 30 seconds, then turn the faucet off, you’d be left with some volume of water (you can measure this, of course!). To calculate the discharge of your faucet, simply divide the volume of water collected by the time it took to collect the water (30 seconds).

When we want to calculate the discharge of a stream or a river, we would likely need a very large measuring cup to collect all of the water coming downstream for any period of time! So, we use a different approach. Turns out, we can also calculate discharge by multiplying the velocity of stream water by the cross-sectional area of the stream channel. Velocity is always expressed as length per time and area is always expressed as length squared. Multiplying velocity by area, we get volume per time (e.g. litres per second, cubic feet per second, cubic meters per second, etc.). Simply a different path to the same result – a discharge measurement!

My friends and I have been graciously trusted with fancy and expensive instruments, which can accurately measure the velocity of flowing stream water, as well as the cross-sectional area of the stream channel. So, whenever we have the chance to visit a stream, we can easily measure discharge. But, we cant be everywhere all the time. So the dilemma arises – How can we know the discharge of many streams in the Dry Valleys all the time?

Turns out, my friends and I have also been graciously trusted with fancy devices that measure the height of water flowing over top of them. We call these devices “stage loggers,” because they can continuously measure the stage (i.e. height) of water, and store the measurements on a small computer chip (data logger). We can deploy a stage logger in a stream and then walk away, knowing that we’ll return to a wealth of data, telling us the height of water in the stream over time. So, lets recap a bit. We are able to measure the discharge of the stream sometimes, but we can measure the stage of a stream all the time.

We use something called “rating curves,” to relate stream stage to stream discharge. “Rating curves,” are mathematical relationships (discharge = f(stage)) between stage and discharge, which allow us to estimate a stream’s discharge, given a steam’s stage. To establish these relationships, we maintain and build control structures. Control structures are built to back-up flowing water behind the structure. This enables us to get very accurate stage measurements at very low flows and very high flows, alike. Below is a photo of our team, working on a control structure located on the Onyx River. Usually these are constructed out of sand bags and rocks.

Stream Team works to re-construct a dilapidated control structure

That’s the brief basics of measuring discharge with rating-curves!

Cheers,

Adam

p.s science is the bees knees, dude.

Antarctic Thanksgiving 2012

Due to the seasonal constraints of studying flowing water in one of the driest and coldest landscapes on earth, I am obligated to spend the austral summer in they Dry Valleys of Antarctica. The warmest annual temperatures, and highest net solar radiation occurs between November and February in this region. This means that I will spend the holiday season away from friends and family in the continental United States. The idea of spending three major holidays (Thanksgiving, Christmas, and New Years) away from home is a bit daunting. However, I have quickly discovered that folks here in the Dry Valleys know how to have a good time with holidays.

I began Thanksgiving day at F6 camp. Unlike previous Thanksgivings, I packed my bags for a scenic hike to Lake Hoare, instead of sitting around watching the Macy’s Thanksgiving Day parade. My colleague,  Tyler, and I set off for the six mile treck (turkey trot) under cloudless blue skies. 2.25 hours later, we arrived at Lake Hoare, where we were greeted by 20 of our friends and co-workers, who were busy making final preparations for a proper Thanksgiving feast.

Chris basting the bird

…. all the fixins

The menu was right in line with traditional American Thanksgiving fare. We enjoyed two turkeys prepared on the grill, mashed potatoes, gravy, sweet potato casserole, cornbread pudding, stuffing, roasted pumpkin and carrots, cranberry sauce, and a nice green salad. For dessert there was a large variety of pies to chose from. Everything was homemade and totally delicious. The best part was the abundance of fresh veggies! It had been a while since I had the chance to chow down on fresh veggies, as they are particularly hard to come by in the Dry Valleys.

dinner inside the main hut at Lake Hoare

After dinner we enjoyed conversation and games over fantastic New Zealand wine. Although nothing is quite like Thanksgiving at home, most certainly nothing is like Thanksgiving in the Dry Valleys. I’m quite grateful for the abundance of good people (and good food) here in the Dry Valleys for the Thanksgiving holiday.

I hope you all had a great Thanksgiving, surrounded by loved ones and tasty food.

Cheers,

Adam

Outside my tent just prior to turkey slumber

Nov 18: Ventifact hike

Hi!

One of the most interesting aspects of the Dry Valleys landscape is the complete absence of vegetation. Without vegetation, the sandy and rocky soils of the valleys are completely exposed to the elements. As winds rip down-valley or up-valley, sand is often picked up and moved through the air. Exposed rocks are weathered by the frequent blasting of wind and sand. Rocks, which have been shaped by this weathering process are known as ventifacts.

Today, Tyler, David, and I took a hike to check out some ventifacts. Check it out…

 

Until next time…

Cheers,

Adam

Nov 16 – 17: Wright Valley, helo-nausea, Blood Falls, and Bonney Camp

Hi!

Allow me to share some recent happenings from the last two days. On Friday morning our helicopter pilot, Flo, picked us up to be flown into Wright Valley to set up some gaging stations. Wright Valley is the first valley north of Taylor Valley, and to get there we took a highly scenic helo trip through the Asgard Range.

View from above the Asgard Range

In the photo shown above, notice polygon patterned ground . This is an interesting landscape feature of cold regions. Patterned ground forms as a result of sequential freezing and thawing of the subsurface, and can be found in most any region underlain by continuous or discontinuous permafrost. Permafrost is defined as soil which has been frozen for more than 2 years. Permafrost is found several meters beneath the ground surface. The shallow sub-surface, which is thawed and then re-frozen each year is called the “active layer”. As the active layer freezes it often cracks, which makes sense because water expands when it freezes. Dont believe me? Fill up a water bottle all the way to the top and stick it in the freezer for a while – see what happens to the bottle. Anyways, the cracked active-layer gets filled with water, snow, and sand. When the winter months come along, this new moisture and sediment re-freezes and expands the cracks further. This is essentially “ice-wedging” – the dominant process behind patterned ground.

We flew into the Wright Valley to set up a gage at the Onyx River. Although currently not flowing, the Onyx river is the largest river in the McMurdo Dry Valleys. In the photo below you can make out the fluvial channel structure, which has been imprinted on the landscape by the movement of water through the valley bottom.

The Onyx river, although it dosen’t have any water yet, you can make out the braided channel structure. Look closely.

At each gage we survey the relative elevation of important features, necessary for the conversion of water height to discharge. Basically the gage boxes record the height of water, also known as stage, at any given moment. When water is flowing we make manual measurements of discharge (volume of water passing per unit of time). By mathematically relating continuous stage measurements to occasional discharge measurements, we can estimate the continuous discharge record of the stream. This is also known as a “rating.” The surveying allows us to account for changes in the infrastructure of the gage system, which is highly important to work the “rating.”

Doing my part to help survey at the Onyx River.

After we wrapped-up surveying, we climbed back in the helo to go scope out a candidate position for a radio antenna. Some of the sites we monitor are rigged up to send data back to the U.S., near real-time. This process is made possible by transmitting a signal from the gage box to a radio antenna, which can relay the signal to McMurdo Station. This complicated process requires that antennae be within eye-shot of the gage boxes, which is why we choose to position antennae at higher elevations. Thank goodness for helicopters.

Checking out the peaks around Wright Valley. McMurdo Sound in the distance

Although climbing above Antarctic mountain ranges in a helicopter is an awesome experience. It is also extremely nauseating, at least I thought so! I spent the remainder of the helicopter ride with a bag in my hands anticipating vomit. Thankfully, I held my own.

We needed to abort our scheduled mission due to the gnarly inbound weather. We were dropped off at Lake Bonney Camp. Lake Bonney is located at the far western edge of Taylor Valley and it backs up against the Taylor Glacier. The lake is split into two lobes – West Bonney and East Bonney. Similar to Lake Fryxell, many glacier-fed steams drain into the lake.

From right to left: Talor Glacier, Lake Bonney West Lobe, and Lake Bonney East Lobe.

There several streams draining the Taylor glacier and feeding into Lake Bonney: Lawson, Sante Fe, Sharpe, and Lyons. These streams give us a reason to visit one of the most novel and interesting areas of Taylor Valley: Blood Falls. Notice the rust colored patch on Lake Bonney West Lobe, above? This is a result of Blood Falls. I cant speak to eloquently about this site, as I am certainly not an expert – but I’ll do the best I can. This part of the Taylor Glacier seeps very very salty and iron-rich water, several times the salinity of sea water. It is believed that relict sea water is trapped within the Taylor Glacier. As this hypersaline and iron-rich water seeps out, iron ions are oxidized as they come in contact with atmospheric oxygen, resulting the highly identifiable orange color. Also, turns out, this water sustains life! Many different kinds or micro-organisms are able to use sulfate as a catalyst to respire with iron ions and metabolize organic matter in the water, all in an anoxic (no oxygen) environment. Jill Mikucki is a microbiologist who has done a ton of fantastic science on this site. This is one aspect of the Dry Valleys, which can be potentially analogous to life on Mars.

Blood Falls hypersaline discharge

Tyler stands amazed by blood falls.

Currently, I am situated at Lake Bonney Camp for the weekend. Bonney Camp is a medium sized camp, maybe twice the size of F6 Camp. I look forward to hanging out with a whole bunch of limnologists (lake scientists) tonight. Should be a fantastic time.

Cheers,

Adam

Traveling is done, and work is beginning

Hi All!

I have finally arrived! After many airplanes, a terra bus, McMurdo Station, a helicopter  Lake Hoare Camp, and another helicopter I am finally settled in at our primary hub of activity – F6 Camp. Located on the beautiful banks of Lake Fryxell, this glorious two-room hut will be home to the MCM-LTER stream team, and other more transient researchers.

F6 camp. Home for now!

The kitchen side of F6. We make some pretty awesome meals, and drink LOTS of coffee

We have one room for cooking/hanging out and another room for laboratory work. Thanks to the good folks at McMurdo Station, we were set up with lots of delicious looking food to keep us going while we are out here. Unlike my experiences at Toolik Field Station, in northern Alaska, F6 is D-I-Y. We make all our own meals, and keep the camp running by completing a long list of daily chores. But when the work is split amongst myself and two other teammates – it’s not so bad. I’ll further elaborate on camp life in a future post.

 

Tyler instals instrumentation inside a gage box at Harnish Creek. I’d love to show photos of streams but there is no liquid water to be found…. yet!

Today was our first day of field work. In brief, the stream team is responsible for maintaining a suite of US Geologic Survey (USGS) gage stations established in 1994, here in the McMurdo Dry Valleys. A “gage station,” basically monitors the discharge of a stream through time. Discharge is the volume of water passing through a cross-section of stream, per unit time. Although this sounds simple – it’s not. There are many streams running throughout the Dry Valleys, which requires us to cover lots of land on any given day. We utilize ATVs, helicopters, and our feet to get from site to site. Also, to put it simply: things break. Trouble shooting and fixing broken stuff often becomes the focal point of our job. Again, I will use future blog posts to explain how we measure discharge in greater detail.

It’s getting late, so for now I’ll leave you with some photos. Enjoy!  ~ Adam

 

Nov 10: Adam meets the Dry Valleys!

Hi!

Very exciting day today! I packed up my belongings at McMurdo field station and put them and myself on a helicopter at 0800 to be flown across the McMurdo Sound to the Dry Valleys. Our helo pilot, Flo, treated me to an exceptionally scenic trip. Photos can do the talking…

Approaching the Asgard range, home to the McMurdo Dry Valleys. Ice covered McMurdo Sound below.

getting closer…

The Ferrar Glacier fills the first Valley South of Taylor Valley, our destination. Almost there…

Taylor Valley!

 

Canada Glacier, viewed from across the helo cockpit.

We eventually arrived at Lake Hoare Camp located on the northern shore of Lake Hoare, which is located ont the western side of Canada Glacier. Upon my arrival, the camp manager, Rae, had hot coffee waiting! What a world we live in! After a brief tour around the small camp facilites, I set up my tent. Sorry I don’t have picture, but I’m camped very close (a safe distance) to the edge of Canada Glacier. This is easily the most beautiful place I have ever been.

I am currently enjoying a pizza dinner with the good folks at Lake Hoare. I have been consistently impressed by the quality of people here in Antarctica, and Lake Hoare is no exception.

Aside from breath taking views and the feeling of being way out there, the most amazing thing is the sound. There is none. When I stand outside of my tent and hold my breath, it’s like being in a vacuum. Think of all the sounds around you right now. Cars, air conditioning, birds, wind through trees, etc. Now errase it. Hard to imagine.

Until next time…

Adam