1. Ice-Based Observatories network in the Arctic Ocean Andrey Proshutinsky, Woods Hole Oceanographic Institution NOAA Arctic Science Priorities Workshop, February 2-3 2005, Silver Spring, MD THEMES:  NOAA activities for the second half of the IPY period  NOAA activities in response to the Arctic Climate Impact Assessment MOTIVATION:  -The Arctic Ocean is high priority target for a diverse set of scientific investigations including key topics such as global climate change, life in extreme environments, navigation, and energy resources.  - The Arctic remains very poorly sampled in comparison to the temperate latitudes. This observational gap represents a critical shortcoming of the envisioned “global” observing system as the Arctic may be the source of major fresh water anomalies that intermittently appear in the subpolar North Atlantic and cause profound changes in the climate system.

2. Proposed Activity: Proposed Activity: Support development and operation of an Ice-Based Observatories network in the Arctic Ocean Major recommendations were formulated by two international workshops supported by NSF:  Instrumentation for Arctic Ocean Exploration, October 16-18, 2002, Moss Landing, CA  Arctic Observing Based on Ice-Tethered Platforms, June 28-30, 2004, Woods Hole, MA NOAA Arctic Science Priorities Workshop, February 2-3 2005, Silver Spring, MD

3. The basic requirements are: ✔ Observation and real-time reporting, with high vertical resolution and high accuracy, of an interdisciplinary suite of parameters from the near-surface atmosphere, sea-ice, and upper ocean for multiple years; ✔ Ease of deployment from landed aircraft and helicopters in addition to deployment by icebreaker; ✔ Modest cost, allowing them to be deployed in large numbers; THE CONCEPT: Ice-based observatories are automated, drifting, ice-based sensor systems providing comprehensive data from the Arctic environment and incorporating the multidisciplinary needs of biological, chemical and physical oceanography, as well as different aspects of atmospheric and sea-ice studies. The basic requirements are: ✔ Observation and real-time reporting, with high vertical resolution and high accuracy, of an interdisciplinary suite of parameters from the near-surface atmosphere, sea-ice, and upper ocean for multiple years; ✔ Ease of deployment from landed aircraft and helicopters in addition to deployment by icebreaker; ✔ Modest cost, allowing them to be deployed in large numbers;

4. Distinguishing features of the IBO concept  The IBO represents and satisfies the multidisciplinary needs of Arctic oceanic climate system covering each of the biological, atmospheric, cryospheric and oceanic regimes;  The IBO provides simultaneous, high vertical resolution data over sea-ice (near surface atmospheric boundary layer), under sea-ice (upper 800m ocean layer), and within sea-ice;  An array of IBOs is envisioned and, similar to IABP array, will allow coverage of more than 40% of the Arctic Basin area;  The IBO reports in near-real time, and data from IBO are openly available via the internet;  The IBO provides communication and data exchange capabilities among different observing systems

5. Proof of concept: IBO prototypes in the field At least four prototypes versions of oceanic observing systems are already operating in the Arctic: At least four prototypes versions of oceanic observing systems are already operating in the Arctic:  IABP buoy array accompanied by Ice Mass Balance (IMB) buoys;  JAMSTEC J-CAD buoy in combination with IMB buoys;  WHOI’s Ice-Tethered Profiler (ITP) in combination with IMB buoy;  North Pole Environmental Observatory (NPEO; which includes Arctic Ocean Flux Buoys (AOFB), J-CADs and IMB buoys.

6. The Mechanics  - Practical, cost-effective and proven IBO designs presently exist, can be readily extended to provide interdisciplinary observations, and should be implemented expeditiously as part of a coordinated Arctic observing system.  - It is envisioned to deploy and operate an array of 30-40 IBOs. This new source of atmospheric, sea ice, and oceanic data from all seasons and from multiple years will increase knowledge of the state and variability of the Arctic by an unprecedented amount.  The publicly available data from the proposed IBOs will provide the basis for both process studies and model validation/assimilation research, work that will ultimately lead to better understanding of the Arctic's role in global climate change.  - Once fully implemented, an array of IBOs will complement bottom anchored, drifting float, and/or alternative ice-mounted measurement systems.

7. Ice-tethered profiler – key element