Ross Island Meteorology Experiment (RIME) Workshop

 

Byrd Polar Research Center

 

The Ohio State University

 

September 11-13, 2001

 

 

Overview:

           

At the Antarctic Meteorology Workshop at Madison in June 1998, discussions were held to determine future directions for the Antarctic Meteorology Program within the National Science Foundation Office of Polar Programs.  Opinions were solicited from a number of U.S. and international scientists regarding the research direction for the next decade.  A document entitled Antarctica:  Barometer of Climate Change was prepared in late 1998 based on the comments received.  The document was circulated in hard copy form and is available on the web at http://www-brpc.mps.ohio-state.edu.  It was proposed that a first step toward a better understanding of the role of Antarctic meteorological processes in the global climate system was to undertake a major field study in the Ross Sea region, the Ross Island Meteorology Experiment (RIME).

 

As noted in the document, the Ross Island area is subject to a wide variety of stable boundary layer phenomena and is adjacent to the Ross Sea where intense air-sea exchange takes place in the large polynya located off the northwestern edge of the Ross Ice Shelf .  It was noted that a wide variety of air-ice-ocean interactions take place in the region surrounding Ross Island and strong topographic forcing is a notable characteristic of the area.  McMurdo Station on Ross Island, being the main logistics base for U.S. operations in Antarctica, is already surrounded by a detailed meteorological network.  The logistical importance of the Ross Sea sector to the U.S. Antarctic Program, the documented importance of meteorological processes in the region, and the complex topography (that provides a very different environment than the SHEBA project) make this an ideal location to conduct a detailed observational and modeling study.  It is hoped that through such a field study, higher quality forecasting support for U.S. operations at Ross Island will result.

 

 

Goals of RIME:

 

The goal of RIME is to better understand the meteorology of the Ross Sea region.  It has been documented that Antarctica plays an important role in the fluxes of mass, heat and momentum toward middle and low latitudes on time scales ranging from the synoptic to seasonal and beyond.  Before it is possible to accurately assess the role of the Antarctic on global climate, it is necessary to understand details of the local meteorology.  The Ross Sea sector is viewed as representative of processes and transports over the entire Antarctic continent.  An understanding of this critical area will be the first step in understanding the interaction of Antarctic processes in the global system.

 

The focus of RIME will be on time scales from less than a day to on the order of a week.  It is thought that topographic forcing will be the key process to be considered.  Improved understanding of Antarctic dynamics and heat balance on these time scales will enable correct representation in models of all types. Modeling will be an important element of the study.  It is the glue that binds all the elements below together, and links closely with weather forecasting.

 

 

Geographic Scope:

 

RIME will have a broad focus area extending from Wilkes Land on the west to West Antarctica on the east, and from the Ross Sea to the north to the South Pole.  It is anticipated that the effort will be international in scope.  Detailed focus areas include Ross Island (mainly U.S.), Terra Nova Bay (Italy, U.S., France), and possible the Dome C region (Italy, France).

 

 

Specific Research Topics:

 

1.      Process Oriented Research:

 

Unlike the case in much of the middle latitudes, the meteorology of the Ross Sea region is strongly governed by local topography.  Strong interaction between marine and continental environments takes place within the Ross Sea sector. A key component of RIME will be to study the topographic modification of the low-level wind, temperature and moisture fields associated with external forcing such as from cyclones. It will be important to define key situations that would not only test the robustness of the modeling efforts but also would be of significant logistical importance.  Special observing periods will be established to examine representative cases in detail.  Possible topics of study include mesoscale cyclogenesis, dynamics of katabatic winds near and beyond the end of the terrain slope, barrier wind generation, topographic modification of synoptic-scale cyclones, and adjustments between marine and continental environments.

 

 

2.  Mesoscale Modeling Research:

 

Modeling has become a key factor in improving the quality of forecasts.  Modeling also provides a means to conduct basic research into atmospheric processes.  The overall goal will be to improve the quality of model simulations for both operational and research purposes.  At the Antarctic Weather Forecasting Workshop at Columbus in May of 2000, a number of recommendations were proposed.  Among those include improvements in model parameterizations specific to Antarctica and incorporation of traditional and nonstandard data into model initialization strategies.  RIME will allow detailed model validation in the Ross Sea region.  Some possible topics of study will include parameterization development and testing, optimization of numerics to deal with steep slopes, model initialization, upper boundary conditions and effective assimilation of surface and satellite observations.  As part of the parameterization development and testing, attention will be given to moist processes such as cloud parameterization, cloud-radiation interactions, cloud formation, advection of moisture, fog formation, etc.  In addition, examination of the fluxes of heat, momentum and moisture in the stable boundary layer is important to ensure that the surface boundary layer is represented in a physically realistic manner.  Development of an operational Antarctic analysis system based on available data that would provide the "best" analyses for model initialization.  Of special interest would be incorporating the wide range of satellite observations into the model forecast system.

 

 

Measurement Issues:

 

To conduct a detailed field study such as RIME, a significant observational database is required.  To start, a basic set of year-round observations around Ross Island including all available AWS and radiosonde observations at McMurdo.  It may be necessary to redeploy certain AWS units to alternate locations for RIME.  In addition, acquisition of other measurement platforms will be required.  Examples may include a wind profiler or LIDAR at McMurdo, an instrumented tower with turbulent and radiative flux measurements and sub-surface temperatures.  For specific field campaigns, an airborne observing system, such as by helicopter, Twin Otter, Aerosonde, or NCAR C130.  It may be necessary to launch additional radiosondes in West Antarctica (Siple or Byrd) or Dome C for part of the study.  Throughout the study, integration of satellite observations will be critical.  Satellite product validation will be necessary.  Satellite-derived data sources offer a wide range of applications that need to be exploited.

 

 

Time Line:

 

RIME Science and Implementation Plan due at NSF by middle to end of October

2001

 

Proposals due June 1, 2002.

 

First field season, 2003-2004

 

Second field season, 2005-2006

 

Analysis through end of 2007 or so

 

 

 

Workshop Tentative Schedule

 

Tuesday, September 11:

 

morning:  presentations by participants on topics related to RIME (15 minutes max for each person)

 

afternoon (maybe mid afternoon):  discussion of where we are at, and what the goals of RIME should be, formulate list of research topics and sort participants into groups

 

Wednesday, September 12:

 

morning:  break into groups to discuss details of RIME components (Process Studies, Modeling Research and whatever else we come up with).  Key goals to be established from Tuesday afternoon, subgroups tasked with developing detailed outlines of how to achieve goals.

 

afternoon:  discussion of subgroup results, formation of writing groups, beginning of writing document

 

Thursday, September 13:

 

morning:  finish draft of document for each subgroup.

 

 

Extended Abstracts:

 

We will be preparing a preprint volume for the workshop. The deadline for receipt of extended abstracts of up to 6 pages in length is Friday August 31, 2001.  They should be prepared in MS Word with little or no formatting.  Tables should be in separate files, as should figures.  Figures should be jpeg or tif format, but not bitmap.  Please follow the AMS style for extended abstracts. Email your extended abstract to Ms. Lynn Everett (everett.2@osu.edu) with a copy to bromwich.1@osu.edu and monaghan@polarmet1.mps.ohio-state.edu.