Tag Archives: ICECAPS

Rave Ice

Last winter I was in the midst of my monthly building checks when I went out to visit the Mobile Science Facility (MSF). It was a dark day and snowing lightly. I noticed a flickering light on the snow out of the corner of my eye and proceeded to the back of the building where there are no outside lights. In the shadow of the building and under the angled LiDAR beam the ground was alive with bright green flashes of light.

The LiDAR laser is mounted to the roof of the Mobile Science Facility (MSF) and is part of the ICECAPS project which is looking at atmosphere, precipitation, radiation, and cloud properties over the Greenland ice sheet.
The science techs had noticed these reflected lights earlier, but I had not seen it before. It was truly magical! The lights danced and flickered around lasting only a fraction of a second. Some streaked across in lines, others just flashed a tiny spot, still others revealed intricate interference patterns on the snow. Later that evening the techs and I returned with our cameras. Like auroras, it’s difficult to capture the movement, but still beautiful and interesting none the less!

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It was reminiscent of disco ball lights, but faster and brighter. At first we called it “Disco Ice,” but that wasn’t quite right…lasers, neon green, a high frequency pulse… “Rave Ice” was a better fit.

Intrigued, we decided to do some research to find out what exactly was happening. Was this a normal LiDAR by-product? How was it related to the falling or blowing snow? What did it tell us about current atmospheric conditions? Surprisingly we found almost nothing on the topic. One paper described a similar phenomenon, however the authors said it had only ever been observed in controlled optics research labs and computer programs, never outside. They speculated that snow or ice crystal size, shape, and orientation could be inferred from the light patterns displayed. One of the science techs wanted more information and reached out to the authors sharing some photos we had taken. They were amazed.
This phenomenon has most certainly been occurring since the LiDAR was first installed in 2010. However, it is rare, can only be seen in the dark, and had never been documented until last winter (2016-17). Over the next few months the ICECAPS Primary Investigators, the science tech here, and the optical researchers collaborated to write an article explaining the unique phenomenon. It was published in the July 2017 edition of Applied Optics!

They were able to link the patterns we photographed, the ice crystals we collected, and the shapes and patterns they had modeled in their labs. For example, a bullseye pattern is created by a smooth sided disc, while a bright spot surrounded by six broken dashed lines is a distinct hexagonal plate. We saw both of these patterns and also collected these types of crystals during the event.

It appears that this phenomenon occurs relatively often. When seen from afar the LiDAR beam glints and sparkles reflecting off the crystals. But conditions must be just right to get well defined patterns. There can’t be too much freezing fog, it can’t be blowing tons of snow, it needs to be dark, and there needs to be some precipitation. While any crystals will reflect the laser the most intricate patterns are a result of proper snowflakes and other more complex crystal shapes; something that requires relatively high humidity (so not too cold) and not too much turbulence (otherwise they’ll break apart). Up here it tends to be either very cold, calm, and clear with no precipitation, or warm, humid, and windy with far too much turbulence for complex crystals to form.
Earlier last week however there was an abnormally warm period with very low winds. Temperatures in some areas of Greenland were as much as 50˚F above average. While temperatures here have been around -50˚F the week prior and again this week, during the warm event Summit temps reached +7˚F! This warm spell affected much of Greenland and was so unusual it made the news:
https://thinkprogress.org/omg-heat-wave-scorches-greenland
https://weather.com/news

It also proved to be absolutely perfect conditions for Rave Ice. I had noticed the sparkling LiDAR beam on Tuesday afternoon and knew it would be worth hauling my tripod and camera out there. As I was walking out one of the techs called out on the radio that I should come out to see…and it was some of the best yet. I set up my tripod and started taking pictures while the tech collected snow samples, photographing the ice crystals, and recording meteorological data.

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The science tech in the unheated shelter used to photograph ice crystals

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Observing the Rave Ice

These are some of the crystals she photographed:

And these are some stacked images of the reflections:
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Filed under Arctic, Greenland, Science, Science!, Summit Station, Winter

Lidar

It was lightly snowing last night, ice crystals falling from high, thin clouds as I walked from the Big House to the Green House. Looking towards the MSF there was just enough ice in the air to illuminate the ICECAPS LiDAR – a laser measuring cloud matter, phase, and crystal orientation. ICECAPS is a relatively large, long-term project researching cloud characteristics and their impact on climate. This knowledge is crucial in developing climate models as well as understanding our changing climate. More information can be found here: www.esrl.noaa.gov/arctic/observatories/summit.

Most of the time the laser is invisible, however with just the right conditions enough light can be reflected back to show the brilliant green beam. If you look carefully you can also see the vertical laser, however this is weaker and thus less visible. Beautiful science!

*If you are familiar with LiDARs you may have seen this spelled LIDAR, lidar, LiDAR, or LADAR – according to NOAA’s Digital Coast Blog all spellings are correct though LiDAR is gaining in popularity. 

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The ICECAPS LiDAR here at Summit

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The LiDAR at NOAA’s ARO facility at the South Pole Station

 

An example of the LiDAR data:

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Filed under Arctic, Greenland, Science, Science!, Summit Station

Aurora Borealis

Aurora behind the Big House

Aurora behind the Big House (HDR)

A month since the last plane and a month yet to go, we’ve settled into our respective winter roles keeping the station running and warm. Our focus so far has been to get everything stored for winter and we’re almost there. All the cargo has been moved to the berm, the buildings have been dragged out away from the main station, and our HEO has been working diligently to clear as much snow as possible from around the remaining buildings before the winter storms begin in earnest.

It’s definitely autumn here on the ice sheet. The sun is setting around 7:00pm now and rising around 6:00am, and by 9:30pm or 10:00pm it’s properly dark outside! It catches me off guard…I know it sounds odd, but I’m used to the ice being either light (summer) or dark (winter). I’m not used to seeing the sun set below the great flat white each day, and how fast it changes!

Along with the darkness comes stars, and auroras! We had our first sighting this week. While I’ve seen the Southern Lights this was my first undeniable glimpse of the Aurora Borealis, the Northern Lights.

The MSF, 50m Swiss Tower, and Auroras...

Aurora Borealis over the Mobile Science Facility (MSF) and the 50m tall Swiss Tower…

Auroras illuminate the sky behind the 50m Swiss Tower

Auroras illuminate the sky behind the 50m Swiss Tower

Named for the Roman goddess of dawn, Aurora, the Northern and Southern Lights are formed by the same process. In summary: charged particles carried by the solar wind are deflected by Earth’s magnetosphere and carried towards the polar regions where they interact with the upper atmosphere releasing photons – light. For a more thorough explanation please refer to my previous post here…or check out these websites for more information:
http://www.swpc.noaa.gov/phenomena/aurora
http://odin.gi.alaska.edu/FAQ/

As these charged particles are released by solar flares and carried on the solar wind, aurora events can be forecasted somewhat, though the accuracy is even less than predicting the weather. (http://www.swpc.noaa.gov/products/aurora-3-day-forecast)

The aurora is a beautiful and magical phenomenon, but it is not rare – it is happening nearly constantly day and night! The light emitted is so faint however, that it can only be seen at night. Every planet with a magnetic field has auroras at the poles – those that don’t, such as Venus, still have the occasional aurora, but they are more random and not specifically polar.

Ultra violet aurora on Saturn.

Aurora on Saturn seen in ultra violet

Over the past few days we’ve had stronger winds and more blowing snow in the air, while this has obscured the night sky it did illuminate the normally invisible LiDAR instrument shining through it’s little window in the MSF roof. A very strong laser, the LiDAR instrument is part of a suite of experiments that compose the ICECAPS project that are studying precipitation and cloud properties over the Greenland ice sheet. Check out the official Polar Field Services blog for a more complete summary: polarfield.com/blog/tag/lidar

The CAPABLE Lidar visible in the blowing snow

The CAPABLE Lidar visible in the blowing snow

The NOAA Observatory webpage has some interesting information on the MSF and the ICECAPS project found at: http://www.esrl.noaa.gov/psd/arctic/observatories/summit/
The University of Wisconsin website also has a webpage with information on ICECAPS: http://icecaps.ssec.wisc.edu/

Temperatures have stayed fairly warm so far (between 0F and -20F), though we have had the occasional dip down to -40F. The general trend is that it’s either clear, calm, beautiful, and very cold (-30F to -40F)…or windy, overcast, snowing and warm (+5F to 0F). As the winter progresses and the days get shorter temps will continue to fall. It won’t reach the coldest temps seen at the South Pole in winter, but it gets cold enough!

For those who might be curious, Summit’s weather data is publicly available at: summitcamp.org/status/weather

And HDR image of the SOB in the dark.

The SOB at night – the generator exhaust illuminated by the building lights. (HDR)

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Filed under Arctic, Greenland, McMurdo, Stations, Summit Station, Winter

Summit Science!

As in Antarctica, our purpose in Greenland is science – primarily climate research. Summit Station was first established in 1989 to support the Greenland Ice Sheet Project Two (GISP2) ice core and has since become a leading arctic station supporting a wide variety of seasonal and long term projects.

Summit was chosen for its location at the summit of the Greenland ice sheet. Some facts: There are two ice sheets on earth, one in Antarctica and one in Greenland, and as they are near the poles we call them ice caps. According to the National Snow and Ice Data Center (NSIDC – based in Denver) an ice sheet is defined as a “mass of glacial land ice extending more than 50,000 square kilometers (20,000 square miles).”  Glaciated areas less than 20,000sq mi are called ice fields – such as the Patagonia ice field, or the Juneau ice field.
Ice sheets and ice fields are incredibly important to climate research as they are not only highly sensitive to global temperature changes but provide a physical archive of the atmosphere going back as long as the ice has been there. The water molecules of the snow/ice itself contain isotopes that correlate to average global temperatures and between these molecules, bound by the ice, are tiny trapped air bubbles – discrete samples of atmospheric gases. This is one way scientists can measure carbon dioxide (CO2) levels over past millennia. The Vostok ice core for example, provided data on the climate going back over 400,000 years. The European Project for Ice Coring in Antarctica (EPICA) ice core goes back 800,000 years. CO2 levels are of particular interest to climate scientists as there is a direct correlation between global temperature and CO2 in the atmosphere. Over the past 400,000 years CO2 levels in our atmosphere have fluctuated between 180-280ppm. Since the Industrial Revolution and large scale burning of fossil fuels those levels have continued to rise. Right now we are close to 400 ppm. (check out http://www.esrl.noaa.gov/gmd/ccgg/trends/ for recent levels) The US Environmental Protection Agency has a great website with information on greenhouse gasses and carbon dioxide, trends in the US, and ways to reduce emissions: http://www.epa.gov/climatechange/ghgemissions/gases/co2.html.

The GISP2 borehole in 2011

The GISP2 borehole in 2011.

The GRIP borehole 28km from Summit Station

The 1989-1992 European Greenland Ice Core Project (GRIP) borehole 28km from Summit Station

GRIP Ice cores at the University of Copenhagen in Denmark

GRIP Ice cores at the University of Copenhagen in Denmark

Annual layers are visible in the cut GRIP cores (U. of Copenhagen)

Annual layers are visible in the cut GRIP cores (U. of Copenhagen)

Greenland Ice core sites

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A graph showing CO2 levels from an ice core (Vostok, Antarctica). Our current atmospheric CO2 levels are off this chart.

While the GISP2 ice core was completed over 20 years ago, Summit continues to provide valuable data. As one of NOAA’s Earth Systems Research Laboratories the Greenland Environmental Observatory (GEOSummit) provides long term monitoring of the Arctic environment and atmosphere.  Much of climate research relies on these trends and long term variations to distinguish climate change from variable weather patterns. TAWO (Temporary Atmospheric Weather Observatory) houses a suite of instruments collecting continuous measurements of a number of greenhouse gasses including carbon dioxide, tropospheric ozone, and black carbon among others. Summit’s science techs launch ozone sondes weekly to measure upper atmosphere ozone and collect air samples twice monthly to be processed for trace gases. Once a month the science techs complete a GPS survey (IceSAT) for CryoSat – providing calibration data for a European Space Agency satellite measuring ice thickness around the globe.

Some other long term projects here at Summit include: ICECAPS (Integrated Characterization of Energy, Clouds, Atmospheric state, and Precipitation at Summit) which is studying the atmosphere, clouds, and precipitation. Today a third station science tech position has been added to focus primarily on the ICECAPS instruments. BSI (Biospherical Instruments) is monitoring ultraviolet radiation. GEOFON has a seismometer buried away from camp as part of a global network. A magnetometer has also recently been installed to measure geomagnetic variations in central Greenland.
This season a new intermediate ice core drill was tested near Summit. The proposed project will drill a 1,500m ice core at the South Pole Station in the 2014-15 and 2015-16 seasons. More information on this project can be found here and on the official SPICE Core site.
The complete list of currently funded projects is publicly available on the Arctic Field Projects site.

Some other interesting links:
http://www.esrl.noaa.gov/gmd/obop/sum/
http://nsidc.org/cryosphere/quickfacts/icesheets.html
http://en.wikipedia.org/wiki/Ice_core
http://www.gisp2.sr.unh.edu/

During the summer of 2011 I was one of two station Science Technicians at Summit.  We monitored and maintained the long term research equipment on station, trouble shooting and repairing as needed. We also assisted with launching weather balloons and ozone sondes and collecting various samples for projects. A typical day included doing rounds to clear meteorological equipment of snow/ice/frost/rime, cleaning lenses collecting data on solar radiation with ethanol, backing up data or sending it via email to researchers at their home institutions, collecting air and snow samples, measuring accumulation rates, launching weather balloons, conducting GPS surveys, and assisting around the station as needed. Here are a few pictures of Summit science techs in action…

Launching a weather balloon in April 2011

Launching a weather balloon in April 2011

Measuring accumulation rates at Summit

One of the 2010 techs measuring accumulation rates at Summit

Radiometers measuring solar radiation and albedo

Radiometers measuring solar radiation and albedo

Bundled up for IceSAT

Bundled up for IceSAT – GPS equipment is in the red “Poly Pod” behind me, the survey takes several hours and is done once a month.

Leveling the seismometer

Leveling the seismometer

Cleaning rime off a tower

Conducting maintenance on the 50m “Swiss Tower”

Cleaning rime off the TAWO tower

Cleaning rime off the TAWO tower instruments

Air sampling flasks!

Crates of  air sampling flasks!

Inflating a balloon

Inflating a balloon in the S.O.B.

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Launching an ozone sonde to collect data on the upper atmosphere ozone layer

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Filed under Arctic, Greenland, Science!, Summit Station