Introduction: our plan
Functioning Ice Mass Balance
buoys as of 1 September 2008. The buoys were deployed in conjunction with
the NPEO, the BGEO, and DAMOCLES. The magenta circles denote possible
locations for new buoy deployments.
One key element of our deployment plan is to continue our long-term partnerships with the North Pole Environmental Observatory (NPEO) [Morison et al., 2002] and the Beaufort Gyre Environmental Observatory (BGEO). The NPEO has been operating since 2000 and has a team of several different investigators regularly deploying instruments including an IMB, an ice-tethered ocean profiler, an ocean flux sensor, a meteorological station, and a sea floor mooring. The Beaufort Gyre is hypothesized to be a flywheel of the Arctic Ocean circulation [Proshutinsky et al., 2002] i) regulating variability of sea ice drift, thickness and concentration; ii) accumulating and releasing freshwater and heat; and iii) interacting with the Greenland Sea Gyre to promote decadal variability of the Arctic climate. Beginning in 2003 the IMBs have been deployed at the BGEO with an ice-tethered ocean profiler and an ocean flux sensor,.We recognize the importance of international collaborations in building a Sustainable Arctic Observing Network. Towards this end, we will also continue our established collaboration with the European Union scientists involved with Developing Arctic Modelling and Observing Capabilities for Long-term Environmental Studies (DAMOCLES) project. Our ongoing AON-IPY project has been fully integrated with DAMOCLES, with 10 IMBs having been deployed as an element of the extensive DAMOCLES atmosphere-ice-ocean observing array.
Specific site locations for the moorings are
determined using ice thickness distributions generated by sea ice dynamics
models. New sites are located to take advantage of existing measurement
sites and activities and historical data records, including the
Pole Environmental Observatory, the
Arctic Buoy Program, and the SCICEX cruises. The eventual goal is a comprehensive,
sustainable Arctic-wide network of autonmous
The ice thickness is monitored with a
combination of moored
ice-profiling sonars (IPS) and drifting
ice mass balance buoys (IMB). Model estimates of the basin-wide mean annual
ice thickness are used to guide deployment of the moored
ice-profiling sonars (IPS). Currently we are
using the Polar Science Center Pan-Arctic Ice-Ocean Modeling and
Assimilation System (PIOMAS)
model, operated by Jinlun Zhang. PIOMAS is a coupled ice/ocean model with a
spatial resolution of 40 km, driven by NCEP/NCAR reanalysis surface air
pressure and air temperature field.
Early results from the model (see plot on right) suggest that data from an IPS site in the Chukchi Sea, north of Barrow, Alaska, coupled with results from an existing IPS site at the North Pole could explain 90% of the variance of the basin-wide, annual mean thickness. This compares to a maximum total variance of 72% at a single point not far removed from the North Pole.