Aeolian worlds

    The Wormherder's search for life in the Dry Valleys is focused on soils. We have been collecting samples from a wide variety of habitats (from Antarctic perspective). We know soils are places that shelter from drought, protect from rapid temperature changes, and provide nutrients. The reason most organisms in the Antarctic are either in the lakes or based on the soil.

    After crossing Lake Fryxell, barely avoiding a dunking
    After crossing Lake Fryxell, barely avoiding a dunking.

    No kidding. Where else would they be - that's where life is all over the planet. Well, how about this - little oases of life in a small aquarium in the middle of a glacier? Thats the aeolian lifestyle. It was a rarely used word for me - one of those you have read before and know the context but never said out loud.

    Cracking open a cryconite hole
    Cracking open a cryconite hole.

    Open cryconite hole on Canada Glacier
    Open cryconite hole on Canada Glacier.

    An aeolian sediment is one that is wind blown. I've written in previous entries about the affect of color on melting, the strong katabatic winds of the Dry Valleys, and the specific adaptations of Antarctica's endemic species. These features combine together to produce the cryoconite hole community.

    Aeolian sediment up close
    Aeolian sediment up close.

    Cryoconite is wind blown - aeolian - sediment that collects in ridges and fissures of an ice sheet. Because of its dark color it has a tendency to melt the ice surrounding where it collects. This melting results in liquid water in the summer months sometimes. Within that cryoconite are nutrients, bacteria, and even small animals. Once the conditions allow, these organisms begin to grown and form a whole ecosystem in the little puddle of water high up on the glacier (or in the middle of a frozen like. Some of them are quite spectacular, with a layer of clear ice covering the tops, protecting the contents from UV rays and freezing temperatures - a little greenhouse on the ice.

    This cryconite melt area looks like a mini glacial valley
    This cryconite melt area looks like a mini glacial valley.

    Out on the lake the result is large sections of crusty ridges of ice. I thought this one looked like a mini Antarctic valley. Earlier in the Antarctic summer the cryconite holes are more distinct. As the summer continues these may combine in larger melt pools as the excess liquid water runs off and collects. These pools can refreeze over the top. They are beautiful from above.

    Refreeze pool on a glacier
    Refreeze pool on a glacier.

    Always bring extra socks

    We got a couple wet socks and boots trying to walk across the recently frozen tops of these cryconite holes in the ice of Lake Fryxell recently. I filmed this video earlier about the different melt rates of ice and the affect it can have on travel. Make sure to check it out.

    McMurdo Station, Antarctica
    Weather Summary
    Partly Cloudy - It is nice!
    Wind Speed
    SE @ 10
    Wind Chill



    Good Morning Mr Henske, I was wondering how cold it get in Antarctica and how do you stay warm

    Bill Henske

    Hi Bronson-
    It isnt too cold in the summer. The coldest it has been was about 10F. Most of the time it is in the 20s. What can be dangerous is the windchill. The key to staying warn but not too warm is layering and managing your layers. What can happen is that you sweat while working but when you stop the sweat evaporates away your heat.

    Bethany Elder

    Hey this is Bethany you don't know me but I am in Mr. Dickersons class and I just think it is s cool how you can stand on the ice that is probably so frozen and how you can stand on it I honestly thing it is preety awesome to be put there but I bet it is also freezing cold can't wait to talk more BYE!

    Bethany Elder

    Hey thanks for resonding to me I have a question for you though how is it posible that you can leave food anywhere?


    The food cannot spoil because there are no microbes. There are no microbes because it’s always below freezing and there is very little water. Just like food in your freezer never spoils.

    Eli Swasey

    This is Eli Swasey, I am in Mr. Dickersons class and I have a question about the stuff you do in antartica. When you guys pull organisms out of the ground where do you put them and how do you get them back to a lab?

    Bill Henske

    Hi Eli-
    We put the soil samples in these little plastic bags and store them in a cooler make sure they stay cold until we can extract the animals back at the lab. We usually put the samples in a cooler that is then loaded in the basket of a helicopter.

    kyler prina

    what temperature does it have to get for the ice pools to form

    Bill Henske

    interesting question- Im glad you asked.- it actually doesn't need to get above freezing! The sediment and rocks absorb solar energy so they heat up higher that the air temperature. Then they melt the water! Depending on the intensity of the sun there can be melting at 20F

    Odin M

    This is Odin, I am in Mr. Dickerson class and I have a question about the stuff you do in Antarctica. When you guys pull organisms out of the ground where do you put them and how do you get them back to a lab?

    Bill Henske

    Hey Odin- We put the soil samples in these little plastic bags and store them in a cooler make sure they stay cold until we can extract the animals back at the lab. We usually put the samples in a cooler that is then loaded in the basket of a helicopter.

    Braedon Johnson

    At what temperature does the Cryconite melt areas melt?

    Bill Henske

    They can start melting at low air temperatures - remember that its the rock material absorbing the energy from the sun and then gaining thermal energy. Its like a heater. Melting can happen at 20F- it just depends on the color and density of the rocks.

    Gabe Johnson

    How windy does it get in Antarctica?

    Bill Henske

    Sooo windy. I went on a hike today and had to turn around because I thought I might get blown into the ocean. Usually winds are in the teens but today the gusts we over 50mph. Katabatic winds in the dry valleys have been close to 100 mph

    Keira Jackman

    Hey Mr Henske! I'm wondering how you know it's an icepool? It looks just like normal solid ground. Thanks!

    Bill Henske

    If I were smarter I'd bring an ice axe and tap as I went. You can go behind someone else and if they fall in, dont go that way. There is a distinct sound where you can hear ice falling below you. That means you are on a layer of ice above the actual lake.

    Owen Wight

    This is Owen Wight, I am in Mr. Dickerson class and I have a question about the stuff you do in Antarctica. Why is there so much wind even though its so cold? The reason I'm asking is because you have to have heat to produce energy and energy makes wind.

    Bill Henske

    Thats a great observation. The katabatic winds are a little different from normal sun driven winds. so- cold air is dense and warm air is less so. The polar plateau is very cold and very high. When a polar mass of air gets near a valley pass it starts to pour over the pass. With the mass of the air behind it, it starts to move very fast. It is a mass of air falling!

    Sara Jackson

    It's interesting how the newly frozen tops on the cryconite holes can have such a large affect in travel

    Gavin stratton

    Hey this is Gavin im one of Mr Dickersons students and I was woundering how can you tell if it is a water shed.

    Bill Henske

    Hi Gavin- you can tell by the shape of the stream system. It is like a tree and its twigs, branches and trunk. The twigs lead to branches (little streams to bigger streams) that lead to the trunk (the main water body of the watershed) In most of the US watersheds lead to oceans but in the Dry Valleys and parts of Utah and Nevada the watershed is a pond or lake whose only outlet is the sky. On the lake surface the water can collect because liquid lakes up less space than solid water so when the ices melts there is more space to fit the liquid water.

    Gavin stratton

    Thanks for taking your time to respond to my question!

    Emma Bryant

    Hey this is Emma Bryant, I am one of Mr. Dickerson's students. I was wondering like how did you know first that it was an ice-pool when from the surface/afar looks like just normal solid ground?

    Bill Henske

    When my boot got wet. Walking across the lake there are places where you can hear the ice breaking and falling- underneath - you. Thats a bad sign!


    How do you know your by ice pools the ground looks the same everywhere?

    Bill Henske

    Hi Katelyn- It can be hard to tell. You always have to be cautious when walking across the lake. If you break through one of these pools you need to get back to camp and get dry right away so you do not het hypothermia.

    Matthew Schmidt

    You said that there were animals in the cryoconite. What types of animals are they? I'm assuming there are nematodes, but do you know if there are any others?

    Bill Henske

    Well keep in mind that they had to blow there from somewhere else to get into the cryoconite hole! You won't find a penguin or seal. Just little things such as bacteria, ciliates, rotifers, and tardigrades. These are all capable of being wind blown, especially when in anhydrobiosis. Nematodes will thrive once a community is more established (like in soils) so I don't think they are found in cryoconite holes very often.

    Arthur Zollinger

    I have a question about the wind-blown cryoconite. Does the amount of cryoconite deposits change if your go higher in elevation? Are the sediments less likely to blow up-hill rather than fall downhill and settle at lower elevation?

    Bill Henske

    Hi Arthur - the wind tends to flow from the polar plateau into the valley- so down hill - but that is something one of our team members is trying to find out. He has these devices called sediment traps that catch the sediment as it blows through different places. Then we can look at what sediments collect and where (and if there is any active DNA/RNA in the sample indicating life on the wind). They aren't really good at telling us the direction that it came from but you can infer from wind data from the various weather stations. Scientists are trying to determine how the organisms travel- where did they come from, where will they spread. We can look at how their genes travel from one population to another.

    Brody Jones

    Hi I am from Mr. Dickersons class and I was wondering how much organisms are in one of the holes

    Bill Henske

    Hi Brody- Thats a big question. It depends what scale organism you are looking at- There are 0 organisms bigger than 5 mm. There "might" be a few larger than 1 mm (like tardigrades) but probably all of them are less than 0.1 mm. There might be millions of bacterial cells and 1000s of rotifers. We actually did not take any cryoconite hole samples so I can't tell you definitively.