Expressions of Intent for International Polar Year 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Arctic Mechanisms of Interaction Between the Surface and Atmosphere  (AMISA 2008)

Outline
The rapid shrinking of Arctic sea ice cover during the past few decades has enormous consequences for polar and global climate, as well as for human commercial activities. Understanding the processes contributing to this reduction is of primary concern, particularly in the light of the dramatic reduction in ice area during summer 2007. The AMISA (Arctic Mechanisms of Interaction between the Surface and Atmosphere) is a NASA-sponsored International Polar Year (IPY) project to understand the impact of the large-scale atmosphere on the surface energy budget (SEB) of the Arctic boundary layer (ABL) and sea ice melt and freeze processes. Tropospheric synoptic and mesoscale disturbances over the Arctic Ocean force large, transitory changes in the structure of the ABL and its SEB. These changes determine the near-surface air temperature and drive the thermodynamic and mass balance of sea ice. The thermal, kinematic, and cloud features associated with these disturbances modify the kinematic and thermodynamic structure of the ABL through both turbulent and radiative fluxes and changes in ABL clouds. These changes subsequently affect the SEB of the pack ice. Evidence exists that specific late spring and late summer disturbances trigger the onset and end of the melt season, respectively, suggesting the importance of these events for determining the length of the melt season. An observed increase in the Arctic melt season has been suggested as a major reason for the decrease in spatial extent and mass of Arctic pack ice. Understanding the processes linking atmospheric synoptic and mesoscale disturbances to ABL structure and SEB during the seasonal transition periods is crucial to understanding the mechanisms linking climate change to trends in pack ice extent. To understand the overall dynamics of the ice-atmosphere interaction process, accurate observations of Arctic sea ice cover and type along with meteorological conditions representative of mesoscale processes are required. NASA EOS sensors such as AMSR-E, AIRS/AMSU, and MODIS, can provide many of the necessary sea ice and meteorological observations, but cannot accurately measure ABL cloud and moisture content nor easily discriminate between summertime meltponds (which produce different radiative and turbulent fluxes) and leads. Moreover, summertime atmospheric clouds and moisture variations affect spaceborne measurements of sea ice by full occultation of MODIS and partial occultation of AMSR-E. A complete study of the ice-atmosphere interaction process thus requires satellite-based data augmented by regional-scale in situ data that can only be provided by airborne and ship-based sampling. To provide this required data we have integrated a ship-based meteorological campaign occurring during IPY on the Swedish ice breaker Oden with an airborne campaign using the NASA DC-8 aircraft. The aircraft measurements will include high resolution microwave imagery of sea ice using the Polarimetric Scanning Radiometer (PSR) system, discrimination of fresh water meltponds using an L-band radiometer, and direct sampling of thermodynamic and cloud variables over wide areas using in situ cloud probes, dropsondes, and radiometric profiling. The observations are occurring immediately south of the AMSR-E blind disk during August-September 2008 in the vicinity of the Oden. The uniqueness of AMISA will be to provide the first observations of summertime Arctic sea ice and atmospheric state variables with high enough spatial resolution and three-dimensional specificity to elucidate in detail the ice-atmosphere interaction processes that occur during freezeup. The observations will specifically be required to understand the impact of mesoscale and turbulent atmospheric processes on surface-energy transition-to-freezeup conditions and the impact of aerosols on Arctic cloud production, along with providing critical data required to improve the AMSR-E sea ice algorithm during summertime Arctic conditions. The simultaneous occurrence of the Oden IPY campaign and this proposed one represents a rare opportunity to combine extensive surface-based point measurements with spatial airborne measurements to validate and improve the capabilities of satellite remote sensing instruments and to address questions important for understanding recent changes in Arctic pack ice.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
In conjunction with the ASCOS IPY project, the AMISA project intends to advance the understanding of surface and atmospheric radiation and cloud and aerosol dynamical processes leading to Arctic sea ice freezeup. It also intends to improve satellite imaging of Arctic sea ice by improving satellite retrieval algorithms for sea ice concentration in the presence of clouds and meltponds.

What international collaboration is involved in this project?
AMISA is being closely coordinated with the ASCOS project. One of the AMISA Co-Is (Prof. Michael Tjernstrom) is also a PI on the ASCOS project.

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
The NASA DC-8 flights for AMISA will occur out of Kiruna, Sweden, and focus on observations over the Oden at ~87N, 0W. The area north of the Fram Strait and Svalbard enoute to the Oden will also be intensively sampled.

Approximate timeframe(s) for proposed field activities:
Arctic: 08/08            
Antarctic: n/a

Significant facilities will be required for this project:
All logistical support for AMISA is being provided by NASA, CU, and the participating institutions.

Will the project leave a legacy of infrastructure?
No, other than new instrumentation developed for use on the DC-8 during AMISA.

How is it envisaged that the required logistic support will be secured?

Has the project been "endorsed" at a national or international level?
Yes - AMISA is a U.S. NASA IPY project that has been formally and successfully proposed under a 2006 NASA call for IPY proposals.

PROJECT MANAGEMENT AND STRUCTURE

Is the project a short-term expansion (over the IPY 2007-2008 timeframe) of an existing plan, programme or initiative or is it a new autonomous proposal?


AMISA is being coordinated with ASCOS.

How will the project be organised and managed?
The project is organized and managed by NASA DFRC and the University of Colorado. Additional partners participating in AMISA include scientists from NASA, NOAA, the University of North Dakota, the University of Colorado/CIRES, the University of Leeds and the University of Stockholm, Sweden. Funding for this mission is provided by NASA.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
1) A combined meteorological/engineering seminar series at CU on remote sensing of the Arctic environment is being planned by the PI and Co-Is. 2) Regular status reports on AMISA flights with preliminary scientific findings are being generated and published on NASA and university web sites set up for AMISA.

What are the initial plans of the project to address data management issues (as outlined in the Framework document?
The University of Colorado will support a data server to make all AMISA accessible for the duration of the project (three years). Negotiations are occurring to have the AMISA data served by NSIDC after the end of the project.

How is it proposed to fund the project?
The AMISA project is funded by NASA, with instrument contributions from NOAA and the University of Colorado.

Is there additional information you wish to provide?
Currently, the most updated AMISA web site is at: http://www.nserc.und.edu/missions/AMISA.html

PROPOSER DETAILS

Prof. Albin Gasiewski
University of Colorado
Dept. of ECE/ Center for Environmental Technology
0425 UCB, Boulder, CO
80309-0425
USA

Tel: 303-492-9688
Mobile: no
Fax: 303-492-2758
Email:

Other project members and their affiliation