As you know from my earlier journals, we are studying the particles that are floating in the air and also landing on the snow. I have written about how we collect the particles that have landed on the snow surface. This journal entry will be about how we capture the particles floating in the air.
Our collecting starts in “TAWO” – the Temporary Atmospheric Watch Observatory.
The Temporary Atmospheric Watch Observatory (TAWO) at Summit Station, Greenland
On top of building are three air filters that Mike and Brandon installed in May.
Kevin McMahon is changing the air filters on top of TAWO.
Each of these filters captures the particles from the air. One set of filters will come back to Georgia Tech to be analyzed. Another set of these air filters will go to the University of New Hampshire and the third set will make their way to the University of Wisconsin, Madison. Each school will be trying to figure out what these particles are made of and will share their findings with each other.
Very expensive machines are inside TAWO and they do some pretty interesting things.
The LASAIR
The LASAIR
The LASAIR Machine sucks in air and then counts the numbers of particles in that air sample. The LASAIR is able to count the number of some VERY, VERY small particles.
The PSAP
The PSAP
The Particle Soot Absorption Photometer also sucks in particles. But, instead of counting them, it looks at how much these particles are absorbing light from the sun or reflecting it back. The more that a particle absorbs the sun’s energy, the warmer the air can become.
The CCN Machine
The CCN
The CCN Monitor
Did you know that a cloud starts to form on bits of particles floating in the air? Water vapor can grab onto some of these particles and turn back to liquid. We actually have a machine up here that can count the number of “cloud condensation nuclei”. That is a fancy way to say we can count how many particles in the air that could help form a cloud. We call this machine the "CCN."
The NEPH
The “Neph” (or Nephelometer) takes in a sample of air and then shines light through it. It measures how much light is being scattered by the particles in the air.
The
With all of this different data, Mike and Brandon hope to get a better idea of how these air particles are affecting how much sunlight is reaching the surface of the Greenland ice sheet and what impact the aerosols are having on the climate here.
Did you know that ice crystals in the air can also bend sunlight? When that happens, you get some pretty spectacular skies, like this one below.
Brandon Strellis in front of a halo.