| RAMMB CIRA 4th Quarter Report |
|---|
July August September 2008 |
Work on the“Kyrill” continues. This storm produced widespread wind damage over Germany and surrounding location. This storm occurred in mid January 2007. A simulation of the event was conducted with RAMS and WRF. Synthetic GOES-R ABI imagery was produced from both models. Last quarter, we obtained the community radiative transfer model, version 1.1. With the help of Paul van Delst, we can now obtain optical depths that are specific to a wide variety of satellites. In particular, we can produce synthetic Meteosat-8 imagery for this storm. (L. Grasso, D. Zupanski, M. Zupanski, I. Jankov, M. Sengputa, and R. Brummer)
The 3-4 april 2007 MCS case over the southeast United States was run again. This time the model was initialized at 00 Z 3 April 2007 as opposed to 12 Z 3 April 2007. This was done since the run initialized at 12 Z produced unfavorable results. The new run has produced better results. (L. Grasso)
As a first step at producing synthetic GOES-R ABI imagery at 0.47 µm, we approximated surface albedoes at this wavelength by reducing surface emmissivity values at 3.9 µm. The test was conducted at one time from the 23 October 2008 fire simulation. As a comparison, one synthetic image at 3.9 µm took about twenty minutes with fifteen processors; one synthetic image at 0.47 µm took 46 hours with fifteen processors. (L. Grasso and M. Sengupta)
Collaboration continues between CIRA in Fort Collins and Boulder. Efforts continue with the production of synthetic GOES-R ABI imagery from the WRF model. In addition, Isidora is helping me compile the wrf_v3.0. (L. Grasso and I. Jankov)
GOES-10 imagery over South America was analyzed for volcanic ash from the Chaitén volcano (42.5°S, 72.39°W, 962 m elevation) in Southern Chile. The last major eruption occurred on 6 May 2008. Figure 1 contains various image combinations over a small but still active ash plume on 30 June 2008 at 2028 UTC. The image differences were generated by Principal Component Image (PCI) analysis, with the lower-right panel representing the longwave split-window (10.7 and 12.0 μm) difference, which is known to be one of the better image combinations to show ash plumes. PCIs are being used to assess which band combinations/differences are the best at detecting the ash plume. These efforts at volcanic ash detection are a continuation of hazards-related GOES-R Risk Reduction activities at CIRA. There is a potential GOES-R product in that the 12.0 μm band has been removed from the last three satellites in the current-GOES series and will not appear again until the first satellites in the GOES-R series. GOES-10 (and GOES-11) still contain the split-window bands to generate this difference product. Work will continue by applying RGB (3-color) analysis to the image differences to generate a product that highlights the ash plume. The GOES-10 imagery for this product was supplied by Tim Schmit at NOAA/NESDIS/ASPB, because the low angle of GOES-10 as viewed at the CIRA ground station in Colorado causes some of the data to be noisier than data collected in Wisconsin. (D. Hillger)
Figure 1: A four-panel display of Principal Component Images (PCIs) generated from all 5 bands of GOES-10 over the Chaitén volcano in southern Chile. The image was taken at 2028 UTC on 30 June 2008. The upper-left panel is a weighted-mean of all five GOES-10 bands, and the lower-right panel, which shows the ash plume best (spreading out to the northwest from the location of the volcano, marked by a red arrow and volcano name), is primarily a longwave split-window (10.7 and 12.0 μm) difference, constituting a very small portion of the signal in the 5 GOES bands. The other panels show image features mainly associated with clouds.
McIDAS code has been written to convert Meteosat Second Generation (MSG) data collected at the CIRA ground station into McIDAS format. The CIRA data is currently stored in XPIF 2-byte binary files, with the resulting format being McIDAS AREA files. The translation code will be made available to anyone who has access to the CIRA MSG archive. The code allows MSG data to be available to more users at CIRA. MSG contains several spectral bands that are similar to those that will be available on GOES-R ABI. (D. Hillger, S. Kidder)