Convective Available Potential Energy (CAPE) as derived from the GOES-East and GOES-West Sounders
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A look at the Convective Available Potential Energy (CAPE) as derived from the GOES-East and GOES-West Sounders is provided each hour. This is a new experimental feature in the suite of DPI displays. Recall that the nominal GOES Sounder field-of-view (fov) is 10 km at the satellite sub-point. Spatial averaging over a 3x3 fov box is currently employed to increase the signal-to-noise. This image is derived from the full physical retrieval algorithm.
However, please note that this image is a "pseudo" DPI, having been re-created after the fact in a image format from the CAPE values available from the 3x3 retrievals, along with use of the 11um window channel (for those areas where no retrievals were made). The CAPE product displayed is an atmospheric stability parameter for a given vertical thermodynamic profile, which indicates the amount of positive (buoyant) energy available to an idealized parcel, ascending from the Level of Free Convection (LFC) to the Equilibrium Level (EL). The larger the value (or the "positive-energy area" under the parcel curve on a thermodynamic diagram), the more unstable would the atmosphere be. A CAPE of 1500 J/kg would indicate a modestly unstable airmass. The values are color-coded with brown/beige>blue>yellow at the more stable end while red>magenta/purple would indicate considerably more potential instability. (Note that transitions between colors beige/blue/yellow/red/magenta occur at CAPE values of 1000, 2000, 3000, and 4000 J/kg respectively). This enhancement table is experimental and suggestions for improvement are welcome. A time sequence of the images remains the best way to monitor stability trends.