Submitted by Anonymous on Mon, 06/06/2011 - 19:23
Forums
Solar Radiation on the Greenland Icesheet 2011

We have enjoyed reading your journal entries.

Question#1: Does all of the AWS stations require maintenance every year or just when the sensors do not respond? (Seems like you worked on the AWS last year).

Question#2: I notices the new antenna's you have been installing look like plastic pipe? I work with GPS for surveying and most of the antenna's are circle? Can you tell me what the difference is?

Question#3: The pictures you have taken are great. With the light reflecting off the snow are you using a filter?

Tue, 06/07/2011 - 17:01

Jim Pottinger

Hi Philips family! It's great to hear from you! Here are the answers to your questions:
1) Each year, Dr. Steffen conducts a north and south traverse of Greenland to check on each AWS. Within that traverse he has specific items that need to be done at each AWS. For example, this year we installed four new data loggers out of the ten stations. The time to install a new data logger can be three to four hours, so as the stations continue to function, they need updated data loggers. Other stations that get high rates of snow accumulation might need to be raised in order to stay above the annual snow fall. Or, we may not get to the station due to weather and will need to return next year. For example, the GITS AWS was a station we had to abort due to poor visibility.
2) The antennas you saw are actually satellite antennas. The white pipe is used to communicate with the polar orbiting ARGOS satellite. The other antenna is used to communicate with the geostationary GOES satellite. The AWS stations that communicate with the GOES satellite use the circular GPS antenna, mounted on one of the lower arms, you are probably familiar with.
3) Thank you for the complement on my pictures! I am using a handheld compact Samsung with no modifications, it's just the way light reflects in the Arctic. It's truly amazing! One of the coolest things I noticed is the optical illusion I get when looking out at the horizon. It looks like I am in a giant bowl, the distant horizon looks like it curves upward. This is due to refraction.
Thanks for your questions and I look forward to seeing you all back in PA!
Sincerely,
Jim Pottinger