Campaign : Fall 1997 SCM IOP

1997.09.15 - 1997.10.05

Lead Scientist : David Randall

Data Availability

The fall 1997 SCM IOP was conducted from 1500 UTC on September 15, 1997, to 0300 UTC October 6, 1997. During this time, 817 soundings were launched that reported data. This represents 99.0 percent of the potential 825 soundings flown (165 3-hourly launch opportunities at five sites) during the IOP. Of the successful launches, 799 soundings (or 96.8 percent) of the maximum possible) ascended above 10 km.

The statistics of soundings by launch site were as follows:

Launch Successful Ascents Missing

Site Launches above 10 km Soundings

CF 159 (96.3%) 154 (93.3%) 6 **

B1 165 (100%) 161 (97.6%) 0

B4 164 (99.4%) 159 (96.3%) 1

B5 164 (99.4%) 161 (97.6%) 1

B6 165 (100%) 164 (99.4%) 0

** Note: One missing sounding due to NCAR Formvar ice replicator sonde launch on September 26.

The percentage of successful launches and soundings ascending above 10 km was outstanding, and provides a high level of sampling that characterizes the atmospheric state in the column. These data will be used in objective analyses to provide atmospheric forcing terms for SCMs.

Of particular interest to the ARM SCM researchers is the wealth of supporting data from the other IOPs conducted during this time, especially the Cloud IOP. The detailed data sets will provide an unprecedented opportunity to evaluate details of the GCM parameterizations being tested.

For data sets, see below.

Summary

The mission goal for the SCM IOP is 21 consecutive days of successful Rawinsonde launches from three Boundary Sites. There may be periods during the 21 day operation where a single, or multiple sites experience brief to extended conditions when launches are not possible. Through coordination between the Site Program Manager, Site Scientist, and Site Operations Manager, the following shut down and restart criteria have been established:

A. A single site failure which will result in the loss of 4 or more consecutive sonde launches is the threshold for stopping the IOP at the BF sites. Conditions which may produce this condition include severe weather (winter storm), electric power loss, and Rawinsonde equipment failure.

Should this condition become imminent, an emergency coordination meeting will be called between the Site Program Manager and the Site Operations Manager to discuss the situation and make the decision to shut down the exercise. After the decision is made, Site Operations will notify all sites of the shut down. All IOP activity and Temporary Site Operator Personnel will be placed in a stop work status. Continuous coordination between the Site Program Manager and the Site Operations Manager will result in the decision to re-start or terminate the SCM IOP.

B. Should the Central Facility experience or be forecasted to experience any shut down exceeding 12 consecutive hours, the SCM IOP will also be shut down. Emergency coordination between the Site Program Manager and the Site Operations Manager will assess and determine the potential for re-start or if the outage is severe, the decision to terminate the IOP. Upon making the decision for IOP shut down, Site Operations will notify all site personnel. All SCM IOP activity and Temporary Site Operator personnel will be placed in a stop work status until the decision is made to re-start or terminate the IOP.

C. If the shut down is an emergency condition situation, every effort will be made to gracefully shut down the affected facility. However, the safety of personnel takes precedence and if the shut down requires immediate evacuation, the graceful shut down may not be possible. The responsible site operators will return to the site after the danger condition passes, and effect a graceful shut down of the site.

D. Should the SCM IOP be temporarily stopped, and the decision is made to restart the exercise, Site Operations at all BF sites will commence with the start of the next scheduled work shift (i.e., if the shut down is for 24 hours, and starts in the middle of the evening shift, the restart would occur with the start of the mid shift the following day.

Description

Goals: The focus of the Single Column Model (SCM) IOP is to develop and test physical parameterizations relating to the understanding of clouds and radiative transfer extracted from General Circulation Models (GCMs) or other large scale models. Specific issues include:

  • Providing detailed temporal characterization of winds, temperature, and moisture within the atmospheric column over the SGP CART Site
  • Providing, as boundary conditions, the advective tendencies and vertical velocities that are the dynamic forcing normally calculated with a GCM

Additional Information

Management Structure: SCM IOP Chief Scientists: Dave Randall, Colorado State University Office phone: (303) 491-8474 E-mail: randall@redfish.atmos.colostate.edu

ARM DSIT Representative: Ric Cederwall, Lawrence Livermore National Laboratory Office phone: (510) 422-6831 E-mail: rcederwall@llnl.gov

Data Single Point of Contact: Participants: Principle Investigator: - Dave Randall, Colorado State University Instrument/System: - CART BBSS Research Participants: - none

Campaign Data Sets

Campaign Participant Data Set Archived Data
Cederwall, Richard ncdc-synop-maps Order Data
Jakob, Christian European Centre for Medium Range Forecasting Order Data
Randall, David scm-forcing Order Data