H.Pedersen
In recent years it has become evident that the Antarctic continent offers remarkably good conditions for astronomical research. It seems justified to ask whether or not similar conditions exist anywhere in the northern hemisphere. We can only surmise that the Greenland ice cap presents those conditions, which most approach the Antarctic.
Over most of the ice cap, topographic conditions should bode for a laminar air-flow, one of the prerequisites for fine seeing. At Summit (72.6 N, 37.5 W) the ice reaches 3220 meters over the sea and winter temperatures drop below -60 C, favoring IR and microwave astronomy. Here, and at several locations within ~100 km weather monitoring has been done for several years, supported by ice core drilling projects. The registrations include basic data such as temperature, wind speed, wind direction, barometric pressure and humidity. We have studied data provided by Department of Geophysics (Copenhagen University) and american data (which can be retrieved by anonymous ftp from uwaaws.ssec.wisc.edu). Cloudiness was registered during the years 1963-70 at DYE 2 and 3, two radar installations in southern Greenland (this data, which is of meager quality, was supplied by the Danish Meteorological Institute). During the winter months, 45 - 55 percent of the time was registered as clear. Further north cloudiness is expected to be less.
During the coming two summers, a new drilling site will be established approximately 300 km north of Summit. Numerous C130 Hercules flights will establish the camp. This opportunity may be used to gather further meteorologial data, launch microthermal balloons, or to install a seeing monitor for operation during the winter season. This northern site is well removed from the auroral circle. Bibliography:
by: J. Forrer and M.W. Rotach " On the turbulence structure in the stable boundary layer over the Greenland Ice Sheet" in: Boundary Layer Meteorology Vol85: 111-136, 1997 See also:
-NASA detects rapid thinning of Greenland's coastal ice.
-Interactive Arctic Environmental Atlas.
AMAP: Arctic Monitoring and Assessment Programme