Scientists and programmers at SSEC/CIMSS have been working with Hydra within McIDAS-V to augment its functionality, enabling it to view data from the Cross-Track Infrared Sounder (CrIS) on JPSS Satellites (Suomi-NPP, NOAA-20 and NOAA-21). How is this functionality accessed? After downloading the McIDAS-V package, and opening it, a user will need to configure User Preferences, as shown in the image below.

In the Preferences window, change the Toolbar Options so that ‘Show HYDRA GUI’ is included. That’s demonstrated in the toggle below. Highlight ‘Show HYDRA GUI’ on the left (under ‘Actions’), then click ‘Add’. Once this is done, as you’ll see below, there is a ‘Hydra’ GUI tab on the McIDAS-V front page, as shown here.

---

What kind of data are expected by the Hydra plug-in? You can order the data from NOAA’s CLASS System. At that website, before ordering, change the User Preferences, accessed from the left toolbar as shown below.

The User Preferences that Hydra expects are ‘Package Geolocation with JPSS Data Products’; Hydra needs this as ‘Yes’ because it expects data and geolocation data to be in the same file. Note that this is different from other software packages, such as Polar2Grid, that expect data files and geolocation files to be separate (albeit ultimately in the same directory). I did click ‘Yes’ on ‘Deaggregate JPSS Data Products’ but this did not appear to have an effect as I expected (which would be to put all granules in one file).

The data to order are shown here; under the ‘Please select a product to search’ drop-down menu, choose JPSS CrIS SDR Operational, (Note: SDR means Sensor Data Record) and either choose by times (I typically go to this website to find the series of times that I want) or location. For this example, I choose NOAA-20 data from 1240 to 1255 on 26 October 2024. (This website shows the swath from Greenland to the Aleutians). After ordering the data, you’ll get an email showing where the requested data are stored, as shown here. The file names at that include many granules. The file name structure shown below includes both the Geolocation information (‘GRCSO’) and the CRiS data (‘SCRIF’), as shown below. If you hadn’t specified ‘Package Geolocation with JPSS Data Products‘ under User Preferences, NOAA CLASS would return individual SCRIF and GCRSO files the Hydra (today) cannot interpret correctly.

---

Put all the files specified in the email into a local directory. You’re now ready to display them using Hydra, so click the Hydra icon in the McV window. When you do that, you’ll see the window appear (below) from which you can point to the directory where the data sits by selecting ‘File(s)’ under the ‘File’ tab.

After selecting all the files within the directory into which I placed the GCRSO-SCRIF files, and clicking ‘Open’, the Hydra window changed. Note that the swath of data overlays what you might have expected given the swath from the SSEC Polar Orbit Track website. Once the swath appears, click on ‘Display’ in this window.

‘Display’ will open another window that shows two probes and the swath. I moved the probe values, and resized the window, and the result is below. The CrIS spectra at the two points are shown — and you can drag the probe locations around the image and see how the spectra change in real time. In this case, the ‘warmer’ (‘cooler’) location’s spectrum is shown in white (cyan). The data in the lower image are CrIS data at wavenumber 902.25 (that is, 11.1 micrometers). That can be changed either by dragging the green line or by entering a value in the box at the bottom of the window.

The window below shows how things change when the green line is dragged to the right, and released. Wavenumber 1661.875 (that is, 6.02 micrometers) is shown in the large window now.

---

Now, under Tools there is a ‘Transect’ choice. If you choose that, a solid line will appear in the window, as shown below. I’ve moved it so it’s start/end points coincide with the two probe locations, and that is shown below.

The Wavenumber 1661.875 Brightness temperatures along that line are shown below. If you drag the endpoints of the transect line above, the transect displayed below will change in real time. If you click on that solid triangle in the center of the transect, you can drag the entire line, and you’ll also see the transect below changing in real time.

Other functionality available includes the creation of RGB imagery from CrIS data, and the creation scatterplots (and density plots) that compare two different channels on CrIS. Becoming familiar with wavenumber spectra is an important process given that a geostationary atmospheric sounder (GXS) is scheduled to fly on GeoXO, scheduled for launch in the mid-2030s. The version of McIDAS-V that includes the functionality described herein is available at the Daily Build link here. This daily build is created every day with all of the previous day’s programming changes.  Therefore, not everything has been fully tested. If you are prompted for a user/password: ‘mcv’ will work for both.

---

I am indebted to Bob Carp, SSEC, for his help in understanding the functionality of this software. Thanks are also due to Bill Line, CIRA, for asking for (and funding!) this expansion in functionality.

View only this post Read Less

The 1200 UTC sounding from Hilo HI (91285) was unavailable on 29 October 2024. (Here is the sounding from 0000 UTC). When such a failure happens, there is a backup: NUCAPS profiles show thermodynamic information that is retrieved from infrared and microwave information on NOAA-20, NOAA-21 and MetopC satellites, and a profile is usually available around 1200 UTC in Hawaii. The plot below shows available NUCAPS plots over Hawaii at 1144 UTC, 29 October. Note the yellow dot over Hilo; Yellow typically means the infrared retrieval failed to converge, and the profile information is therefore coming from microwave data. (Green points show profiles where the infrared solution converged to a solution.) The profile from the yellow point over Hilo is below.

The NUCAPS profile at Hilo, below, shows a relatively moist boundary layer, a strong inversion with a top near 750 mb, and relatively moist air between 300 and 500 mb. In the Sounding Availability plot above, profiles that did converge to a solution are located northwest of Hilo, just offshore of the Big Island, and to the east of Hilo. Those profiles are shown below. They show features similar to the profile at Hilo.

---

When fate interferes with your ability to view rawinsondes, NUCAPS can step in and help. A good practice is to compare the profiles when rawinsondes are present so you can better understand how they compare.

View only this post Read Less

The Storm Prediction Center’s Fire Weather Outlook, issued at 1700 UTC on 28 October (link), shown below, shows a critical weather day over portions of Oklahoma, Kansas and Texas. The forecast office in Norman, OK, noted the fire risk, Red Flag Warnings and Wind Advisories on its front page.

The Next Generation Fire System Alerts Dashboard monitors satellite imagery to detect the hot spots that indicate wildfires. A screen capture of the Alerts Dashboard is shown below (The Alerts Dashboard has been modified so only alerts in TX and OK are shown), with an alert shown for Logan County in OK, north of Oklahoma City OK. By clicking on the triangle, satellite data associated with alert can be accessed.

The satellite imagery revealed once a user clicks on ‘Satellite Imagery’ above is shown below. This shows the NGFS Microphysics RGB. In addition, the pixels where the fire has been detected are highlighted; the color of the pixel outline is a function of the estimated GOES-R derived Fire Radiative Power. The slider allows a user to move forward and backward in time to help conclude if action is required. Note also the button that says ‘Open in RealEarth’. That opens a RealEarth instance that includes all the NGFS fire products.

The RealEarth instance of NGFS, for the same time, is shown below.

The animation below shows Fire Temperature RGB and NGFS Microphysics RGB animations from 1721 to 1836 UTC. The fire detection in both RGBs shows up at 1746 UTC. High clouds mean it is a challenge to maintain the RGB signal, but the NGFS signal persists as high clouds move overhead.

CSPP Geosphere true-color imagery, below, shows a complicated scene. The moving high clouds make it difficult to identify — visually — any fire detections.

---

The CIMSS Prototype NGFS website is here.

View only this post Read Less

GOES-18 Airmass RGB imagery, above, from 1500-1820 UTC on 28 October, show light snow over much of central Alaska as a storm system moves into the state. Temperatures at 500 mb, below, derived from NUCAPS profiles (as shown in the toggle), show a tongue of warmer air positioned with the cloud feature (shown as white) in the RGB above. Temperatures in that warm(ish) tongue of air (bluish in the enhancement) are around -25 to -27^oC versus the Bering Sea (magenta in the enhancement) where they are around -35^oC. Temperatures at 850 mb over the Bering Sea (shown here with a color enhancement that ranges from -25^oC to +10^oC) are around -6^oC.

Snowfall Rates, estimated from ATMS on Suomi-NPP (from this site) show snow moving slowly north between 1324 and 1504 UTC over western Alaska.

Did your eye jump on the heavier Snowfall rates over southern Alaska? The region around Anchorage is in a Winter Storm Warning; 6-12″ is expected, more than the lighter values expected across the central part of the state.

View only this post Read Less