SSEC 2003 Highlights—More Information
SSEC Infrastructure and People
Auspicious BeginningsThe Scanning-HIS is flown on NASA’s high-altitude aircraft, the ER-2, in validation campaigns to test and calibrate the new AIRS instrument on NASA’s Aqua satellite. As is hoped, the two instruments show agreement in tenths of degrees K.
ASAP goals account for advanced capabilities of next generation satellite instruments. Areas of expertise include convection, product integration, satellite assimilation, cloud properties, data management, product integration, validation efforts, wind measurements, volcanic ash, and turbulence. Ozone and water vapor products will be produced as affected by turbulence.
Measurements of collocated skin temperature and surface air temperature were collected at all 3 ARM-CART sites, and on some ships. Relationships between the two temperatures are used to assign a skin temperature to each profile based on lowest level temperature.
This research involves the study of boundary layer convective cloud features using high-temporal resolution water vapor profiling data. The results utilize AERI data collected every 40 seconds by the AERIbago during the CRYSTAL experiment in 2002. This research represents the first use of this new, high temporal resolution data in boundary layer research. The premise behind this work is that convective cloud rolls induce water vapor perturbations (updraft=positive pert. (moistening), downdraft=negative pert. (drying)) that can be detected by the AERI instrument. Therefore, we calculated these perturbations within the boundary layer (at a 315 meter height) and performed a power spectrum analysis to assess their periodicity. We found that a spectral peak existed between 17–25 mins. We then analyzed the GOES-8 satellite imagery to determine the true periodicity of these rolls. In performing a geometric analysis using the satellite+sounding derived parameters above, we found that these rolls passed over the AERI instrument site every 23 mins. As you can see, this periodicity corresponded well with that derived from AERI data analysis. We performed an identical analysis using high-temporal resolution Raman LIDAR data (every minute) during IHOP and achieved similar results, thereby validating our hypothesis that we can infer the presence of boundary layer turbulent structures using water vapor profiling data. The publication, “Evidence for the Presence of Roll Structures in the Convective Boundary Layer using Thermodynamic Profiling Instruments,” submitted to the Journal of Geophysical Research, details the results of the study.
The CIMSS ASAP project is the first group to fully exploit all pertinent pieces of information from the GOES sounder into an automated, real-time algorithm to nowcast, or, make extremely short-term forecasts, of initial thunderstorm formation (i.e., convective initiation). The algorithm is unique in that satellite-derived winds are incorporated into the data processing. The winds make it possible to find the past locations of cumulus clouds (and their prior cloud-top temperatures), from which can be determined whether the clouds have exhibited rapid cloud-top cooling, which is the precursor sign of thunderstorm formation. The system has shown skill in numerous cases for forecasting thunderstorm formation only 30–45 minutes into the future. Satellite data are the only inputs, so it can be run over any part of the world that is covered by a geostationary satellite with similar specifications (resolution, spectral bands, etc.) to GOES. It is believed that this product can be very beneficial to aviation interests and the common operational forecaster, especially in locations where a radar network is not present (most of the world). (K. Bedka)
Few ozone features are this apparent during the height of summer, but on 23 July 2003, GOES-12 (eastern half of the image) resolved an ozone feature associated with a synoptic system. July and August typically show very uninteresting ozone fields as high pressure dominates. The summer of 2003, however, started with below normal temperatures and correspondingly high ozone concentrations persisted over the northern tier of states. The high temperature in Madison on this day was only in the mid-70s. (Chris Schmidt, Jun Li)
Rederivation is a method that uses the relative ratio of nadir observations coincident in time and space from two AVHRR instruments, thereby making the calibration of one AVHRR dependent on those of other AVHRRs.
Since about June 2002, SSEC’s Data Center has provided data for Honeywell’s WINN screen and software that pilots use in the cockpit. The Data Center began by providing cloud height measurements from global satellite data. In about June 2003, they added three more products: Winds Aloft, Global Turbulence, and Global Convection.
By December 1, 2003, roughly half The Schwerdtfeger Library’s document collection had been cataloged in MadCat. Of those, 75-80% are unique to this library. Most of the 4200 records added during 2003 required original cataloging.
The work is a collaboration of Unidata with Australia’s Bureau of Meteorology, the National Center for Atmospheric Research, the National Center for Supercomputing Applications, and others. The IDV is a new display and analysis tool based on VisAD, for 2D/3D visualization and next-generation, collaborative data analysis. Unidata is a program operated by the University Corporation for Atmospheric Research and sponsored by the National Science Foundation that enables universities to acquire and use meteorological and other data in teaching and research. SSEC, and Whittaker, have been involved in Unidata since the planning stages in the early 1980s.
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30 April 2004 TG