Imager and Sounder Radiance and Product Validations for the GOES-12 Science Test

I NTRODUCTION

The Geostationary Operational Environmental Satellite (GOES)-12 was launched on July 23, 2001, and positioned in geostationary orbit at 90ºW Following its launch, the National Oceanic and Atmospheric Administration (NOAA) and the National Environmental Satellite, Data, and Information Service (NESDIS) conducted a comprehensive 5-week Science Test from September 23 to October 27, 2001, integrated within the GOES-12 Post-Launch Test (PLT) schedule in collaboration with NASA This report focuses on the NOAA/NESDIS Science Test, which involved extensive system performance evaluations and operational testing of the satellite's instrumentation During the Science Test, GOES-12 operated in a specialized mode, conducting continuous imaging of the continental United States every 5 minutes, alongside various scan schedules for both the Imager and the Sounder.

Several goals were established for the GOES-12 Science Test:

The recent loss of the 12 µm Imager band-5, coupled with the introduction of the 13.3 µm band-6, significantly affects both existing and upcoming Imager products Additionally, a comparison of the Imager water vapor band-3 at 6.5 µm with the previous band-3 at 6.7 µm reveals important changes in data quality and application.

 Investigate and quantify/characterize the quality of the GOES-12 measurements This was accomplished by comparing GOES-12 data to measurements from other satellites and by performing noise and striping analyses.

The GOES-12 satellite generates and validates various Imager and Sounder products, including temperature and water vapor retrievals, total precipitable water, lifted index, cloud-top pressure, satellite-derived winds, sea surface temperatures, and analyses of biomass burning and volcanic ash Validation is achieved through comparisons with data from other satellites, as well as radiosondes and ground-based instruments, ensuring the accuracy and reliability of these atmospheric measurements.

 Investigate the utility of nearly continuous rapid scan Imager and Sounder imagery for improving severe weather forecasts.

The GOES-12 GVAR data stream and ancillary data have been archived for retrospective studies and are accessible on an internal network in McIDAS format The Regional and Mesoscale Meteorology (RAMM) team from NESDIS and CIRA has made the GOES-12 imagery available online through the RAMSDIS Online homepage, while image and product loops can also be found on the CIMSS web pages.

During the Science Test, data from the GOES-12 Imager and Sounder was archived at multiple locations, including CIRA at Colorado State University, SSEC at the University of Wisconsin, and the NESDIS Forecast Products Development Team (FPDT) The FPDT aimed to archive all ingested Imager and Sounder data along with ancillary information such as model data, hourly surface observations, and radiosonde data Both CIRA and SSEC successfully archived the complete GVAR data stream.

SATELLITE SCHEDULES AND SECTORS

During the GOES-12 Science Test, six schedules were developed, incorporating various predefined Imager and Sounder sectors based on input from participating research and development groups These schedules mirrored those used in the GOES-11 PLT (Daniels et al 2001) The NESDIS/Satellite Operations Control Center (SOCC) provided essential support, allowing for considerable flexibility in switching and activating these schedules This capability was crucial for capturing significant weather phenomena of different scales throughout the Science Test, as SOCC could activate a new schedule with just two hours' notice.

Table 2.1 summarizes the six schedules, highlighting that the default C1RAP schedule involved continuous 5-minute scans across the continental United States (CONUS), with the Sounder focusing on the East CONUS view Additionally, the C2SRSO schedule was designed to allow for limited activation of Super Rapid Scan Operations (SRSO) during the testing phase.

Table 2.1: Summary of Schedules/Sectors for the GOES-12 Science Test.

Time Interval Sector / Area Time Interval Sector / Area

Conus, Atlantic Hurricane, Pacific Hurricane, Central/

East conus, West conus, Gulf of Mexico, Tropical Pacific, Caribbean, Central/S America, Volcano, East limb, West limb

C2SRSO Continuous 1 min, plus 5 min conus every hour

C3 Continuous 5 Conus 9 min Colorado, Oklahoma, min or Hurricane 10, 11, or 12

C4 Continuous 8 min South America 1 hour South America

C5 Continuous emulation of GOES-east operations

GOES-east Continuous emulation of GOES-east operations

C6 Continuous 2 min, plus conus every hour

Gulf of Mexico 26-min sector every 30 min

During the Science Test period from September 23 to October 27, 2001, the GOES-12 schedule operated with full flexibility, as detailed in Table 2.2 However, there were a few initial days when the C1RAP schedule was implemented to accommodate Image Navigation and Registration (INR) specification testing.

Table 2.2: Daily Implementation of GOES-12 Science Test Schedules.

September 23 C1RAP conus East conus First Day of Science

September 24 C5 East conus GOES-8 Emulation

September 25 C1RAP conus East conus Pre-arranged tests

September 30 C1RAP conus East conus

October 01 C5 East conus GOES-8 Emulation

October 02 C5 East conus GOES-8 Emulation

October 03 C2SRSO at 15°N 110°W Tropical Pacific Tropical Storm Lorena

October 10 C5 C5 (East conus) GOES-8 Emulation October 11 C5 through 0543 UTC; then C2SRSO at 32°N 95°W

East conus Severe weather in Gulf

October 12 C2SRSO at 32°N 95°W through 0543 UTC; then C1RAP conus

East conus Severe weather in Gulf

October 13 C1RAP conus East conus Saturday

October 14 C1RAP conus East conus Sunday

October 15 C1RAP conus East conus TS Karen – Nova Scotia

October 16 C1RAP conus C1 East limb through 0600 UTC C1 West limb from

October 17 C5 C5 East conus Tranquil Weather

October 18 C1RAP conus C1 West limb through 0600 UTC C1 East limb from

October 19 C1RAP conus East conus Friday

October 20 C1RAP conus East conus Saturday

October 21 C1RAP conus East conus Sunday

October 22 C1 Pacific Hurricane East conus* *Pacific Hurricane request somehow did not make it

October 23 C3 conus C3 Oklahoma Rapid Sounder Scans over Oklahoma October 24 C2SRSO centered at 40°N/

East conus Severe weather in

Midwest October 25 C2SRSO centered at 48°N/

East conus Severe weather in New

England, Large Low north of Great Lakes, Lake Effect Snow

October 26 C1RAP conus East conus

October 27 C1RAP conus East conus Last Day of Science

CHANGES TO GOES-12 (AND SUCCESSIVE GOES) IMAGERS COMPARED

The differences between bands utilized by the two versions of the GOES Imager (Schmit et al.

Table 3.1 outlines the specifications of the Imager on GOES-8 through GOES-11, which features five bands, specifically bands 1 through 5 In contrast, the Imager on GOES-12 and subsequent GOES satellites includes bands 1 through 4, along with an additional band, band-6.

1 0.55 to 0.75 0.65 Cloud cover and surface features during the day

2 3.8 to 4.0 3.9 Low cloud/fog and fire detection

6.75 (GOES-8/11) 6.48 (GOES-12) Upper-level water vapor

4 10.2 to 11.2 10.7 Surface or cloud top temperature

5 11.5 to 12.5 12.0 (GOES-8/11) Surface or cloud top temperature and low-level water vapor

6 12.9 to 13.7 13.3 (GOES-12) CO2 band: Cloud detection

Changes to the GOES-12 Imager compared to previous GOES (8 through 11) include:

 A new band-6 at 13.3 μm at 8 km spatial (line) resolution at nadir This band replaces band-5 at 12.0 μm.

The water vapor band (band-3) is now enhanced with a spatial resolution of 4 km, an improvement over the previous 8 km resolution of current GOES satellites Additionally, both bands are captured at an over-sampled element resolution of 2.3 km Notably, the spectral response of the water vapor band has been slightly adjusted and broadened.

Table 3.2: GOES Imager spatial resolution characteristics.

(GOES-8/11 values are from Menzel and Purdom 1994)

The first full-disk visible image from the GOES-12 Imager was captured on August 17, 2001, at 1800 UTC and is available for viewing at SSEC The full spatial resolution data demonstrated good integrity Comparisons of GOES-12 images with those from GOES-8 and GOES-10 revealed noticeable degradation in the visible bands of the older Imagers and Sounders.

Figure 4.1: The first visible image from the GOES-12 Imager occurred on 17 August 2001 at

One of the first full-disk infrared images from the GOES-12 Imager occurred on 17 September

On January 1, 2001, at 1800 UTC, full-disk images were captured in the infrared window band (band-4, 10.7 μm) and the water vapor band (band-3, 6.5 μm), as illustrated in Figures 4.2 and 4.3 For further details, these images are available at http://www.ssec.wisc.edu/data/goes12/.

Figure 4.3: GOES-12 full-disk image for the water vapor band (band-3, 6.5 μm).

On August 30, 2001, at 1631 UTC, the first visible band image from the GOES-12 Sounder was captured, showcasing its capabilities This image can be compared to a similar visible image from the GOES-8 satellite taken around the same time, providing insights into advancements in satellite imagery For a visual comparison, visit the following link: http://cimss.ssec.wisc.edu/goes/g12_report/G12SOUNDERVIS_30AUG01_TITLE.jpg.

The degradation of the GOES-8 Sounder is evident, while the visible data from GOES-12 has not yet been normalized, resulting in noticeable striping in its images Nevertheless, the GOES-12 image exhibits significantly brighter visuals compared to the GOES-8 image.

The spectral response functions for the GOES-I/M series Imagers are available at the NOAA website, specifically at http://www.oso.noaa.gov/goes/goes-calibration/goes-imager-srfs.htm, and are illustrated in Figure 4.4 For detailed information on GOES calibration, refer to the study by Weinreb et al (1997).

The locations of the four GOES-12 Imager infrared spectral response functions are illustrated in Figure 4.4, overlaying a high-resolution spectrum of Earth-emitted radiation This spectrum clearly shows absorption features attributed to key gases such as carbon dioxide (CO2) and water vapor (H2O), along with other atmospheric constituents.

The spectral response functions for the GOES-I/M series Imagers can be accessed at the NOAA website, providing essential data for understanding the 18 infrared bands of the GOES-12 Sounder For detailed information and visual representation, visit http://www.oso.noaa.gov/goes/goes-calibration/goes-sounder-srfs.htm.

The GOES-12 Sounder IR average spectral response functions are illustrated in Figure 4.5, overlaying a high-resolution spectrum of Earth-emitted radiation The spectral bands cover a range of central wavenumbers from 680 cm⁻¹ (14.7 μm) to 2667 cm⁻¹ (3.75 μm), as detailed by Menzel et al (1998).

Band noise estimates for the GOES-12 Imager and Sounder instruments were calculated using two methods: one involved determining the variance of radiance values in a space look scene, while the other utilized spatial structure analysis as outlined by Hillger and Vonder Haar in 1988 Both methods produced nearly identical band noise estimates, which are detailed below.

The Imager's full-disk images provided valuable space views, enabling the determination of noise values Notably, preliminary noise values for the GOES-12 Imager, recorded on November 5, 2001, at 2100 UTC, were comparable to those of the GOES-11, as outlined in Table 4.1, indicating similar performance between the two systems.

Table 4.1: Preliminary Noise Estimates for GOES-12 for 5 November 2001 at 2100 UTC

Compared to Preliminary Noise Values for GOES-11.

Noise estimation is conducted through spatial structure analysis on a 50-line by 100-element segment of image data This analysis involves comparing adjacent Fields-Of-View (FOVs) to identify the random components of the signal present in the images The study utilized 15-minute imagery from GOES-12 over a six-hour period on November 26, 2001, from 0915 UTC to 1515 UTC The findings for GOES-12 are detailed in Table 4.2, alongside comparable data for GOES-11.

Table 4.2: GOES-12 Imager Noise Compared to GOES-11.

(GVAR count, 10-bit, 0-1023) (K @ 300 K, except band-3

GOES-12 noise is compared to the rest of the GOES series (GOES-8 through GOES-11) inTable 4.3 GOES-12 noise levels compare well with those from the other satellites.

Table 4.3: Summary of the noise (in temperature units) for GOES-8 through GOES-12

Imager bands The specification (SPEC) noise values are also listed.

GOES-12 GOES-11 GOES-10 GOES-9 GOES-8 SPEC

6 13.3 0.19 No band No band No band No band 0.32

The GOES-12 Sounder sectors, which include space views, enable the assessment of noise values through the scattering of radiance values in uniform space Preliminary data from October 19 at 1316 UTC indicates that GOES-12 meets specifications for most bands Figure 4.6 illustrates a line plot comparing noise values of GOES-8 and GOES-12 to SPECS, highlighting the enhancement in shortwave and longwave infrared performance Additionally, the signal-to-noise ratios of GOES-12, measured in radiance units, align favorably with those of other satellites.

Figure 4.6: GOES-12 Sounder noise values (in radiance units) compared to those from GOES-8. The specification noise values for the GOES Sounder bands are also included for comparison purposes.

Structure analysis was performed on half-hourly space-view measurements acquired over a 24-h period: 16 October 2001 [Julian day 289] 1816 UTC through 17 October 2001 [Julian day 290]

1716 UTC East-limb, west-limb, and limb-average values are presented and compared toCIMSS analysis values in Table 4.4.

Table 4.4: GOES-12 Sounder Noise Levels.

Analysis 13-bit GVAR counts (0-8191) (mW/(m 2 ãsrãcm -1 ))

Table 4.5: Summary of the noise for GOES-8 through GOES-12 Sounder bands The specification (SPEC) values are also listed.

4.4 Imager Detector-to-Detector Striping

Striping analysis involves comparing the mean values of each detector over a large image area of 480 x 640 pixels This study utilized 15-minute imagery collected over a 6-hour period on November 26, 2001, from 0915 UTC to 1515 UTC The differences presented in Table 4.6 reflect the average values for each detector against the overall image average, which represents the midpoint between the two detector averages Consequently, the actual striping observed between the infrared band detectors of the Imager is double the values indicated For reference, equivalent values for GOES-11 are also provided.

Table 4.6: GOES-12 Imager Striping Compared to GOES-11.

6 13.3 One detector only No band

F IRST I MAGES

Visible

The first complete visible image from the GOES-12 Imager was captured on August 17, 2001, at 1800 UTC, showcasing good data integrity at full spatial resolution This image, available at SSEC, can be viewed online Comparisons of GOES-12 images with those from GOES-8 and GOES-10 revealed noticeable degradation in the visible bands of the older instruments.

Figure 4.1: The first visible image from the GOES-12 Imager occurred on 17 August 2001 at

Infrared

One of the first full-disk infrared images from the GOES-12 Imager occurred on 17 September

On January 1, 2001, at 1800 UTC, full-disk images were captured in the infrared window band (band-4, 10.7 μm) and the water vapor band (band-3, 6.5 μm), as illustrated in Figures 4.2 and 4.3 For additional details, these images are accessible online at http://www.ssec.wisc.edu/data/goes12/.

Figure 4.3: GOES-12 full-disk image for the water vapor band (band-3, 6.5 μm).

Sounder

On August 30, 2001, at 1631 UTC, the first visible band image from the GOES-12 Sounder was captured, marking a significant milestone in satellite imagery This image can be compared to a similar visible image from GOES-8 taken around the same time, showcasing advancements in meteorological observation technology For a visual comparison, visit the link: http://cimss.ssec.wisc.edu/goes/g12_report/G12SOUNDERVIS_30AUG01_TITLE.jpg.

The GOES-8 Sounder shows noticeable degradation, while the GOES-12 visible data has not been normalized, resulting in striping in its images Nevertheless, the GOES-12 image appears significantly brighter compared to the GOES-8 image.

S PECTRAL R ESPONSE F UNCTIONS

Imager

The spectral response functions for the GOES-I/M series Imagers are available at the NOAA website, where they are illustrated in Figure 4.4 For additional details on GOES calibration, refer to the work of Weinreb et al (1997).

The locations of the four GOES-12 Imager IR spectral response functions are depicted in Figure 4.4, overlaying a high-resolution spectrum emitted by the Earth This spectrum clearly shows absorption features attributed to carbon dioxide (CO2), water vapor (H2O), and various other gases.

Sounder

The spectral response functions for the GOES-I/M series Imagers are accessible at the NOAA website, specifically at http://www.oso.noaa.gov/goes/goes-calibration/goes-sounder-srfs.htm This resource includes the locations of the 18 infrared bands of the GOES-12 Sounder, providing essential information for users.

The GOES-12 Sounder infrared average spectral response functions are depicted in Figure 4.5, overlaying a high-resolution spectrum of Earth-emitted radiation The spectral bands cover central wavenumbers from 680 cm⁻¹ (14.7 μm) to 2667 cm⁻¹ (3.75 μm), as detailed by Menzel et al (1998).

R ANDOM N OISE E STIMATES

Imager

Full-disk images from the Imager offered valuable space views, enabling the assessment of noise values The initial noise values for the GOES-12 Imager, recorded on November 5, 2001, at 2100 UTC, were comparable to those of GOES-11, as illustrated in Table 4.1.

Table 4.1: Preliminary Noise Estimates for GOES-12 for 5 November 2001 at 2100 UTC

Compared to Preliminary Noise Values for GOES-11.

Noise estimation is conducted through spatial structure analysis on a 50-line by 100-element segment of image data This analysis involves comparing adjacent Fields-Of-View (FOVs) to identify the random components of the signal present in the images The study utilized 15-minute GOES-12 imagery collected over a 6-hour timeframe on November 26, 2001, from 0915 UTC to 1515 UTC The findings for GOES-12 are detailed in Table 4.2, alongside comparative values for GOES-11.

Table 4.2: GOES-12 Imager Noise Compared to GOES-11.

(GVAR count, 10-bit, 0-1023) (K @ 300 K, except band-3

Table 4.3: Summary of the noise (in temperature units) for GOES-8 through GOES-12

Imager bands The specification (SPEC) noise values are also listed.

6 13.3 0.19 No band No band No band No band 0.32

Sounder

The special sectors of the GOES-12 Sounder, which include space views, enable the assessment of noise values through the scattering of radiance values in uniform space Preliminary data from October 19 at 1316 UTC indicates that GOES-12 meets specifications for most bands A comparison of noise values between GOES-8 and GOES-12, illustrated in Figure 4.6, shows significant improvement in both shortwave and longwave infrared measurements Additionally, the signal-to-noise ratios of GOES-12, expressed in radiance units, align favorably with those from other satellites.

Figure 4.6: GOES-12 Sounder noise values (in radiance units) compared to those from GOES-8. The specification noise values for the GOES Sounder bands are also included for comparison purposes.

Structure analysis was performed on half-hourly space-view measurements acquired over a 24-h period: 16 October 2001 [Julian day 289] 1816 UTC through 17 October 2001 [Julian day 290]

1716 UTC East-limb, west-limb, and limb-average values are presented and compared toCIMSS analysis values in Table 4.4.

Table 4.4: GOES-12 Sounder Noise Levels.

Analysis 13-bit GVAR counts (0-8191) (mW/(m 2 ãsrãcm -1 ))

Table 4.5: Summary of the noise for GOES-8 through GOES-12 Sounder bands The specification (SPEC) values are also listed.

I MAGER D ETECTOR - TO -D ETECTOR S TRIPING

Striping is assessed by comparing the mean values of each detector over a large image area of 480 x 640 pixels This analysis covers 15-minute imagery collected over a 6-hour period on 26 November 2001, from 0915 UTC to 1515 UTC The differences presented in Table 4.6 reflect the average values for each detector compared to the overall image average, which represents the midpoint between the two detector averages Consequently, the striping observed between the infrared bands of the Imager is effectively double the values indicated For reference, equivalent values for GOES-11 are also provided.

Table 4.6: GOES-12 Imager Striping Compared to GOES-11.

6 13.3 One detector only No band

I MAGER - TO -I MAGER C OMPARISON

On November 5, 2001, at 1805 UTC, GOES-12 was synchronized with the GOES-10 schedule, demonstrating a strong correlation in brightness temperatures at the midpoint between the two satellites (0ºN, 112.5ºW) Table 4.7 indicates a band-3 difference of 2.3 K, attributed to the variations in spectral response functions When these differences are considered, the brightness temperature discrepancies align closely For more details, visit the provided link.

Table 4.7: Imager-to-Imager Comparison Between GOES-12 and GOES-10.

I MAGER - TO -P OLAR -O RBITER C OMPARISONS

During the checkout period, NOAA-15 HIRS and AVHRR data were analyzed alongside GOES-12 data, focusing on infrared (IR) window and water vapor (WV) band measurements collected within 30 minutes of polar-orbiter overpass time A total of 21 comparisons for NOAA-15 in the IR window and 22 in the WV band were conducted, revealing that GOES-12 was approximately 0.3 K colder than NOAA-15 HIRS in the IR window and slightly colder by less than 0.1 K compared to NOAA-15 AVHRR In the WV band, GOES-12 was 0.1 K colder than NOAA-15 HIRS These findings align with previous comparisons of GOES-8 and GOES-10 data, with the exception of the WV band results, which may reflect differences between the new GOES-12 WV band and older GOES WV bands, warranting further investigation as GOES-12 becomes operational.

Table 4.8: Comparison of GOES-12 to NOAA-15 AVHRR and HIRS for the IR window and water vapor (WV) bands.

Comparison (satellites and band) Mean of Absolute

GOES-12 minus NOAA-15 HIRS IR window 0.64 -0.29 0.72

GOES-12 minus NOAA-15 HIRS water vapor (WV) 0.77 -0.12 1.08

C ALIBRATION

Bias Mode (Sounder)

There was a change to the GOES-12 Sounder calibration bias mode (from Mode 1 to Mode 2) on

On 11 October 2001, banding was observed in bands 12 and 15 of the Sounder, particularly around 0400 UTC, due to varying infrared calibration bias factors linked to the temperatures of optical components This banding, which differs from line-to-line striping, was mitigated by switching to Calibration Bias Mode 2, which allows for more frequent calculations of bias factors based on the correlation with optics temperature variations A comparison of band-12 data at 0346 UTC on 11, 12, and 13 October showed a noticeable reduction in striping after the switch, although the complete elimination of banding did not occur until 13 October, as the optics temperature used for regression was not updated until 12 October.

Figure 4.7: GOES-12 Sounder band-12 both before and after the bias mode change Note there is less "banding" by 13 October 2001.

Scan-Mirror Emissivity Coefficients (Sounder and Imager)

On 11 October 2001 SOCC installed a new set of scan-mirror emissivity coefficients (Weinreb et al 1997) in the GOES-12 calibration for both the Imager and the Sounder These coefficients are used in the algorithm that corrects for the east-west scan-angle dependence of the emissivity (and reflectance) of the Imager and Sounder scan mirrors Earlier, the GOES-12 calibration had used emissivity coefficients calculated from a previous GOES The new coefficients were specific to GOES-12, as they were derived from on-orbit GOES-12 data A before and after plot shows how the change was verified by comparing space-looks on the west and east side of two images The "before" (red) line is from 11 October 2001 at 1415 UTC (see Figure 4.8) The

On October 11, 2001, at 14:45 UTC, the analysis of the blue line indicates a significant enhancement in the imagery, particularly noticeable in Imager band-6 The y-axis, representing radiance, is adjusted to focus on the space-view, while the earth-view pixels are scaled off the y-axis in the center of the x-axis, highlighting the improvements in the after image.

The comparison of spatial views on the west and east sides of two images, illustrated in Figure 4.8, highlights the improved alignment after the installation of a new set of scan-mirror emissivity coefficients The red line represents the conditions before correction, while the blue line indicates the enhanced agreement following the adjustments.

Imager-to-Imager Comparison

The Imager-to-Imager comparison utilizes GOES-08/10/12 data collected every half hour from 2345 UTC on November 11, 2001, to 2315 UTC on November 16, 2001, chosen for its comprehensive data coverage over five consecutive days, spanning from 0ºN to 40ºN to include both land and sea The analysis reveals that GOES-8 consistently records lower albedo measurements compared to GOES-12, while GOES-10 shows variable results; some measurements align with GOES-12 while others are significantly lower This discrepancy is attributed to the interplay of solar angle and topography, where GOES-12 captures the illuminated side of mountains when the sun is east of 90ºW, resulting in higher albedo readings, whereas GOES-10 views the darker side Conversely, when the sun is west of 135ºW, GOES-10's measurements increase The pronounced scatter in albedo measurements is particularly evident for land targets, unlike the GOES-8 data, which shows less variability due to the proximity of the satellites and the relatively flat terrain in the comparison region.

The scatter plot in Figure 4.9(a) illustrates the reflectance of GOES-8 (*) and GOES-10 () in relation to GOES-12 reflectance, with GOES-10 samples categorized into morning (red +) and afternoon (blue +) groups Reflectance values represent the arithmetic mean of pixel reflectance within the comparison area A dashed 45-degree reference line is included, while thin solid lines denote least-squares regression lines, indicating the sensitivity of operational GOES satellites compared to GOES-12.

To reduce data scatter, the analysis focuses on the local noon of the target, dividing each of the five targets, spanning 40° in the north-south dimension, into 20 segments of 2° each to enhance sample size The results, illustrated in Figure 4.9(b), indicate a significant reduction in scatter for GOES-10 compared to Figure 4.9(a), while the slopes for both GOES-8 and GOES-10 remain notably consistent This consistency is also observed in land-only and sea-only targets, although those results are not depicted.

Figure 4.9(b): Similar to Figure 4.9(a), but limited to local noon cases only See text for details.

In November 2001, the visible band sensitivity of GOES-8 was approximately 59% of that of GOES-12, while its sensitivity was about 77% compared to GOES-10 These findings are illustrated in Figure 4.9(c), alongside data from earlier intercomparison studies If the Spectral Response Function (SRF) for the visible bands of these satellites had been identical, the sensitivities would have been optimal prior to launch, maintained a constant level shortly after, and subsequently experienced exponential degradation.

Figure 4.9(c): Visible band sensitivity of operational satellites relative to a recently commissioned satellite.

Figure 4.9(d): GOES Imagers (8/9/10/11/12) visible band spectral response functions An AVIRIS (Airborne Visible InfraRed Imaging Spectrometer) spectra (dark blue line) is also shown to demonstrate the transition zone near 0.72 àm.

The infrared bands must be accurately calibrated to avoid systematic bias among the Imagers, although the spectral response function of the water vapor band (6.5 µm) on GOES-12 is intentionally distinct from those on GOES-8/11, leading to significant variations in brightness temperature This adjustment was necessary to capture more signal from the smaller field of view (FOV) (Schmit et al 2001) As illustrated in Table 4.9, there are notable mean brightness temperature differences between the GOES-12 Imager and the GOES-8/10 Imagers for bands 2-4, confirming these expectations.

Table 4.9: Mean brightness temperature difference (K) between the GOES-12 Imager and the GOES-8 and 10 Imagers for the IR bands.

Imager band Ocean Land Ocean and Land

Time series of the brightness temperature differences are plotted in Figure 4.10 to examine the consistency of the overall agreement or difference between GOES-12 and GOES-8 and GOES-

10 In Figure 4.10(a & b), a distinctive pattern of daily variation is apparent for the 3.9 àm band,especially for the GOES-12/10 comparison and, to a lesser degree, for the 11 àm band of theGOES-12/10 comparison This can be explained by the same mechanism that causes the daily variation of GOES-12/10 visible band difference [Figure 4.9(a)] Inspection of the time series(Figure 4.10(a)) indicates that the GOES-12 and GOES-8 brightness temperature difference is small and stable for the 11 and the 3.9 àm bands (at night) The difference for the 6.5 / 6.7 àm band is large (due to the differing SRF) but stable For GOES-12 and GOES-10, no such conclusion can be convincingly drawn, largely because the two satellites were located sufficiently far apart that they viewed the same earth target through significantly different atmospheres and with different insolation conditions.

Figure 4.10(a): Brightness temperature difference [(GOES-12) – (GOES-8)] during the period of comparison The brightness temperatures are arithmetic means of individual pixel values within the area of comparison.

Figure 4.10(b): Same as Figure 4.10(a), but for GOES-12 – GOES-10.

Figure 4.10(c & d) presents ocean scenes, revealing minimal differences in the GOES-12/8 comparisons compared to Figure 4.10(a & c) For the GOES-12/10, the 6.5 / 6.7 µm band shows little change due to its weak dependence on the earth's surface However, daily variations in the 3.9 µm band differences are significantly reduced, with the 11 µm band variations nearly disappearing Despite this, the GOES-12/10 ocean-only daily variation, including the nighttime 3.9 µm band, exhibits larger amplitude fluctuations compared to the GOES-12/8 variations shown in Figure 4.10(a & c).

Another feature (or the lack thereof) confirmed by Figure 4.10(c & d) is that, unlike GOES-11,there is no unexplained variation at local midnight for GOES-12.

Figure 4.10(c): Same as Figure 4.10(a), but over ocean only.

Figure 4.10(d): Same as Figure 4.10(b), but over ocean only.

Histograms of the brightness temperature differences are presented in Figures 4.11(a) and4.11(b) They show no dependence of the differences on scene temperature.

The histograms of GOES-12/08 brightness temperatures for the comparison region during one night reveal consistent agreement in the 3.9 and 11 µm bands Additionally, a notable difference is observed in the 6.5/6.7 µm bands, which remains persistent across all brightness temperature measurements.

Figure 4.11(b): Same as Figure 4.11(a), but for GOES-12/10.

Imager-to-Sounder Comparison

Between 11 and 16 November 2001, when the Imager-to-Imager comparison was made, the GOES-12 Imager was also synchronized with Sounder, making the Imager-to-Sounder comparison more valid In this comparison, the results of which are reported in Table 4.10, Imager band-1 is compared with Sounder band-19; Imager band-4 is compared with Sounder band 8; Imager band-6 is compared with Sounder band-5; Imager band-2 is compared with the mean of Sounder bands 17 and 18; and Imager band-3 is compared with the mean of Sounder bands 11 and 12 In addition, the time series of these differences are plotted in Figure 4.12.

Table 4.10: Mean difference between the GOES-12 Imager and Sounder No correction for the different spectral response functions was applied.

Visible 3.9 àm 6.5 / 6.7 àm 11 àm 13.3 àm

The differences observed in the first three bands may stem from variations in spectral response, while the discrepancies in the last two bands are minimal Notably, the differences between the Imager and Sounder are strikingly similar to those between the Imager and other Imagers, potentially indicating that the GOES-12 Imager is less well-calibrated than the GOES-12 Sounder and the GOES-08/10 Imagers Additionally, a clear diurnal variation in these differences is evident, especially in the 6.5/6.7 and 11 µm bands, with minimum values occurring closer to satellite midnight, which is one hour later than local midnight, likely due to calibration uncertainties.

Figure 4.12 illustrates the variations in brightness temperatures for the IR bands of the GOES-12 Imager and Sounder, as well as the percent albedo for the visible band, plotted over time It is important to note that no adjustments were made for the differing spectral response functions in this analysis.

Figure 4.13: Comparison of GOES-12 Sounder and Imager to GOES-8 Sounder for the 13.3 m band The boxes correspond to regions noted in the tables below.

Forward radiative transfer model calculations for a clear-sky standard atmosphere show theGOES-12 Imager 13.3 m band will have a slightly higher (1.5 K) mean brightness temperature than the Sounder band-5 (Schmit et al 2001).

Sounder-to-Sounder Comparison

A preliminary animated comparison is accessible at [CIMSS](http://cimss.ssec.wisc.edu/goes/g12_report/anis/anigsare.html), showcasing remapped imagery from 19 bands of both the GOES-12 and GOES-8 Sounders, captured at 2046 UTC on September 20.

The CIMSS GOES-12 webpage provides access to additional time periods for satellite data analysis There is significant overlap in coverage between the satellites, although noticeable differences exist The data from the GOES-12 Sounder is less noisy compared to that from GOES-8, and the visible data from GOES-12 appears brighter These variations in observed radiances stem from known differences in the spectral response functions of the two satellites.

Another Sounder radiance comparison, from late in the GOES-12 Science Test at 1846 UTC on

On October 20, 2001, the imagery from the GOES-12 and GOES-8 Sounders was re-mapped to a common Mercator projection, showcasing favorable coverage overlap between the satellites The 19 spectral bands are displayed in a multi-panel format, with Band-1 in the upper left corner and the subsequent bands arranged across rows and down columns, focusing on the central and eastern United States A uniform color enhancement is applied to the 18 infrared bands, while the visible Band-19 is represented in shades of gray Despite a reasonable match in patterns and overall ranges, notable differences emerge, particularly with the GOES-12 Sounder data appearing significantly less noisy compared to the GOES-8 data.

Figure 4.14: All 19 bands from both the GOES-8 (top) and GOES-12 (bottom) Sounders at

To quantify the differences in brightness temperatures between the GOES-8 and GOES-12 Sounders, a comparison was conducted across all 18 infrared bands during a nighttime period The analysis utilized operational spectral response functions for both satellites, focusing on values with similar look angles Results indicate that the brightness temperatures from GOES-12 closely align with those from GOES-8 for the majority of bands However, notable discrepancies of 2 K and -6 K were observed in bands 2 and 15, likely attributed to uncertainties in the spectral response functions of GOES-8.

Figure 4.15: Brightness temperature differences between the GOES-12 and GOES-8 Sounders.

PRODUCT VALIDATION

A number of products were generated with data from the GOES-12 instruments and then compared to products generated from other satellites or ground-based measurements.

T OTAL P RECIPITABLE W ATER (TPW) FROM S OUNDER

Figure 5.1 displays total precipitable water (TPW) retrievals for GOES-8 and GOES-12 over the same area at approximately 1846 UTC on October 20, 2001, using clear radiances in a 3x3 FOV scene The TPW retrievals show a strong qualitative agreement between GOES-8 and GOES-12, which also aligns reasonably well with the radiosonde measurements plotted on the images.

Figure 5.1: GOES-8 (left) and GOES-12 (right) retrieved total precipitable water (TPW) from the Sounder displayed as an image The data are from 1846 UTC on 20 October 2001.

The GOES-12 and GOES-8 Sounder images share identical start scan line times; however, their individual measurements differ due to varying scan sector widths Additionally, the satellites' distinct orbital locations result in co-located fields-of-view being observed through different atmospheric paths These factors contribute to the observed differences in Total Precipitable Water (TPW) between the two satellites.

From October 28 to December 17, 2001, GOES-8 and GOES-12 Total Precipitable Water (TPW) retrievals were compared with radiosonde measurements at 0000 UTC and 1200 UTC daily The retrievals were required to be within 50 km and 60 minutes of each other, as well as in proximity to radiosonde observations Statistical analyses were conducted to assess the accuracy of retrieved TPW against the first guess from the Eta model forecast, with results detailed in Table 5.1 It is important to note that the retrievals utilized radiance bias correction coefficients from GOES-10, and all retrievals were based on 3x3 Field of View (FOV) data, ensuring at least four clear FOVs per retrieval, resulting in a total of 3,229 comparisons.

Table 5.1: GOES-8 and GOES-12 Retrieval/RAOB Co-location Statistics.

Statistic GOES-8 GOES-12 Guess Radiosonde

The GOES-12 Sounder water vapor retrievals exhibit greater similarity to radiosonde measurements compared to those from GOES-8 This improvement in retrieval quality is likely attributed to the lower noise levels present in the GOES-12 Sounder radiances.

Hourly TPW values retrieved from GOES-12 were matched in both time and location with ground-based TPW measurements obtained from a microwave radiometer at the Cloud and Radiation Testbed (CART) site in Lamont, OK, for subsequent analysis.

L IFTED I NDEX (LI) FROM S OUNDER

The lifted index (LI) is derived from temperature and water vapor profiles obtained from clear radiances within a 3x3 field of view (FOV) scene (Ma et al 1999) Figure 5.2 illustrates the retrievals of the lifted index for GOES-8 and GOES-12, presented as an image.

Figure 5.2: GOES-8 (left) and GOES-12 (right) retrieved Lifted Index (LI) from the Sounder displayed as an image The data are from 1846 UTC on 20 October 2001.

C LOUD P ARAMETERS

The integration of the 13 àm band on the GOES-12 Imager enables near full-disk cloud product generation, enhancing the accuracy of Effective Cloud Amount (ECA) calculations compared to previous GOES-8 through GOES-11 Imagers This advancement facilitates more frequent and timely Satellite Cloud Products (SCP), supporting the Automated Surface Observing System (ASOS) while providing comprehensive near full-disk coverage.

On October 20, 2001, at 1846 UTC, a comparison of cloud-top pressure products from GOES-8 and GOES-12 Sounder revealed significant similarities, as illustrated in Figure 5.3 Prior to the GOES-12 Science Test, additional comparisons indicated strong correlation between the cloud-top pressure products derived from the GOES-12 Imager and Sounder, as shown in Figures 5.4 and 5.5 Overall, the results demonstrated a reliable agreement between the Imager-based product and those generated from the complete set of GOES Sounder bands.

Figure 5.3: GOES-8 (left) and GOES-12 (right) retrieved cloud-top pressure from the Sounder displayed as an image The data are from 1846 UTC on 20 October 2001.

Figure 5.4: GOES-12 cloud-top pressure from the Imager from 1445 UTC on 25 September2001.

Figure 5.5: GOES-12 cloud-top pressure from the Sounder from 1446 UTC on 25 September2001.

S ATELLITE W INDS

Comparison of CO 2 Heights and H 2 O Intercept Heights

The GOES-12 satellite employs CO2 slicing and H2O intercept algorithms to determine heights for semi-transparent or sub-pixel cloud tracers, applying both methods to each tracer When both techniques successfully yield a cloud height for a specific tracer, a comparative analysis of the derived heights is conducted Results from this analysis, which includes approximately 1,000 targets, are detailed in Table 5.3, dated 29 November 2001.

Table 5.3: CO 2 slicing and H 2 O intercept cloud tracer height statistics using GOES-12 data on 29 November 2001.

Mean cloud-top pressure (hPa)

Scatter with respect to mean (hPa)

Root Mean Square Deviation (hPa) with respect to:

The CO2 height assignment in the atmosphere is approximately 31 hPa lower than the corresponding H2O intercept height, a finding consistent with Nieman et al (1993), which reported CO2 heights about 30 hPa lower using GOES-7 VAS data The standard deviation for cloud heights relative to mean heights is 68 hPa for CO2 and 88 hPa for H2O, with a root mean square difference of 83 hPa between the two height assignment methods.

Verification of Winds: Assigned CO 2 Heights and H 2 O Intercept Heights

Two distinct sets of GOES-12 winds were produced, utilizing the CO2 slicing technique (SFOV-histogram approach) for the first set and the H2O intercept technique for the second Both wind sets were aligned with the same radiosonde data, enabling a comparative analysis of the verification statistics for each method Verification statistics are detailed in Table 5.4.

Table 5.4 presents a comparison of wind difference statistics at high altitudes (100-400 hPa) using GOES-12 IR data The first column details the statistics derived from the CO2 slicing algorithm, while the second column outlines the statistics obtained through the H2O intercept method.

The statistics indicate consistent quality across different height assignments, with only a minor decrease in RMS and mean vector difference for the CO2 winds However, these winds also display a slightly greater speed bias, highlighting the need for further investigation to better understand these discrepancies.

GOES-12 Imager findings indicate that both the H2O/IR window intercept method and the CO2 slicing technique yield comparable results for determining the heights of semi-transparent cloud elements However, the infrared window band technique tends to underestimate the altitude of these clouds by at least 100 hPa, performing accurately only in denser, more opaque cloud formations (Schreiner and Menzel 2002).

C LEAR S KY B RIGHTNESS T EMPERATURE (CSBT)

A sample image of the GOES-12 Imager Clear Sky Brightness Temperature (CSBT) cloud mask is presented in Figure 5.8 Unlike other instruments, the GOES-12 Imager lacks the 12 µm band, which is advantageous for cloud detection The CSBT plays a crucial role in initializing global numerical models.

S EA S URFACE T EMPERATURE

SST Algorithm Development

Since January 2002, an initial radiative transfer model (RTM) GOES-12 algorithm, featuring minimal cloud corrections and basic sun glint adjustments, has been operational alongside the GOES-8/10 SST algorithms This algorithm was initially tested using GOES-12 data from November 2001, but it later revealed calibration and registration offsets that were not identified until after the algorithm's development.

The study utilized the current GOES-12 algorithm, applying it to GOES-8 operational data while excluding the 12 µm channel, resulting in simulated GOES-12 data The match-up data base (MDB) spans from September 12, 2002, to June 1, 2003, and has undergone offline quality checks The findings of this research are presented in Table 5.5.

Table 5.5: Simulated GOES-12 results using simulated GOES-12 data

The form of the GOES-12 initial algorithm is

The equation a0 + a1*secZ-1 + a2*T3.9 + a3*T3.9*secZ-1 + a4*T11 + a5*T11*secZ-1 is established through regression analysis of simulated clear-sky brightness temperatures utilizing the MODTRAN radiative transfer model This model effectively addresses the bias caused by scattered solar radiation in the 3.9 µm channel.

(4) delta-SST = b0 + sec (SolZenAng)*sec (SatZenAng)*b1.

The scatter plots for day and night are shown in Figure 5.10.

Figure 5.10a: Simulated GOES-12 SST vs buoy SST for day and night.

Figure 5.10b: Simulated GOES-12 SST vs buoy SST day

Figure 5.10c: Simulated GOES-12 SST vs buoy SST

The GOES-12 algorithm is being integrated into operational use in collaboration with the University of Edinburgh, focusing on the implementation of advanced methods for cloud clearing, aerosol correction, and mitigation of sun glint contamination.

F IRE D ETECTION

Basic fire detection primarily utilizes 3.9 µm (band-2) data from the GOES Imager, which is essential for locating fires and estimating their sub-pixel size and temperature The effectiveness of detecting and characterizing fires is influenced by the upper limit of brightness temperature in the 3.9 µm band, as saturation temperature can restrict the number of detectable fires Higher saturation temperatures enhance the ability to identify and estimate fire size and temperature, while low saturation temperatures may hinder the differentiation of fires from hot backgrounds when observed brightness temperatures reach or exceed saturation levels.

GOES-12 shares a similar saturation temperature of approximately 336 K with GOES-8, but their sub-satellite points differ, with GOES-8 located at the equator and 75°W, while GOES-12 was at 90°W during the Science Test This leads to variations in brightness temperature for fire pixels in Brazil's Mato Grosso region, where GOES-8 tends to saturate more frequently than GOES-12 A comparison of three active fire locations at 1745 UTC on October 2, 2001, revealed good agreement in the location and number of fire pixels, despite a 15º difference in satellite view angles Differences in clear-sky non-fire pixels were generally less than 2 K In the first example, intense fire activity saturated both satellites, with GOES-8 capturing a broader impact due to its viewing geometry The second example showed that the fire was hot enough to saturate the GOES-8 3.9 µm band but not GOES-12 In the third example, both instruments saturated, highlighting significant pixel differences likely caused by variations in view angle and fire intensity.

A comparison of brightness temperatures from GOES-10 and GOES-12 was conducted for a hotspot in California, highlighting the importance of elevated saturation brightness temperatures in the shortwave infrared window of the GOES Imager The two satellites had a nearly 9° difference in viewing angles, with GOES-10 observing from the west and GOES-12 from the east, affecting their atmospheric perspectives While the background brightness temperatures around the fires were typically within 2 K, GOES-12 did not show an immediate increase in brightness temperature at the western edge of the fire pixels, likely due to its larger zenith angle GOES-10 saturated at 321.5 K, whereas GOES-12 saturated at 336.3 K, indicating that the lower saturation brightness temperature of GOES-10 complicates fire detection in the Western U.S and limits the ability to assess sub-pixel fire activity in most North American wildfires.

Preliminary indications are that GOES-12 is performing comparably to GOES-8 and much better than GOES-10 insofar as fire detection is concerned.

The Biomass Burning team at CIMSS generates fire products for GOES-10/12, which monitor wildfires across North and South America These valuable data can be accessed on the Wildfire Automated Biomass Burning Algorithm page However, increased cloud contamination can result in a higher likelihood of false ash detection, as detailed in the study by Hillger and Clark (2002).

The evaluation of GOES-8 Sounder data for two weak-to-moderate eruptions aimed to assess the potential negative impacts of losing the 12 µm Split Window IR (SWIR) band Comparisons of Principal Component Images (PCIs) with and without the SWIR were conducted using both subjective pattern recognition techniques and an objective "false alarm" parameter (Ellrod 2001) During daylight, the quality of infrared detection showed minimal differences without the SWIR, likely due to the reflectance peak of silicate ash at 3.9 µm, particularly when the ash cloud was opaque, which limited the effectiveness of the Split Window technique However, at night, ash detection capabilities significantly declined due to increased ambiguity with clouds and surface features This degradation could lead to occasional increases in analyzed ash coverage for aviation safety, resulting in longer route diversions Nonetheless, analysts can utilize image animation to effectively track volcanic ash clouds and approximate their locations.

Major volcanic eruptions can produce persistent ash clouds, which may become difficult to track, particularly when obscured by extensive high-altitude cirrus clouds.

The IR band on GOES-12 effectively differentiates ash from cirrus clouds, but struggles with low-level water droplet clouds and certain surface features As illustrated in Figure 5.11, the scatter plot displays Brightness Temperature Differences (BTDs) ranging from 11 µm to 13.3 µm from the GOES-8 Sounder, specifically for an ash cloud originating from Popocatepetl volcano on the night of January 23, 2001 Notably, significant variations in BTDs exist between cirrus and ash at specific IR temperatures, facilitating their distinction.

Figure 5.11: Scatter plot of Brightness Temperature Differences (BTDs) from the GOES-8Sounder for an ash cloud from Popocatepetl volcano on 23 January 2001 at 0420 UTC (night).

On October 9, 2001, during the GOES-12 Science Test, the volcanic ash detection capability was evaluated following a small ash emission from Popocatepetl, located near Mexico City A comparison was made between a PCI using the 3.9 µm, 11 µm, and 12 µm infrared bands from GOES-8 and a similar image utilizing the 3.9 µm, 11 µm, and 13.3 µm bands from GOES-12.

At 1445 UTC, the small ash cloud is clearly visible in both the GOES-8 and GOES-12 images, with GOES-8 offering superior contrast However, the GOES-12 image seems to underestimate the ash cloud's area coverage, particularly without data from the 12.0 µm band Consequently, while analysts can still detect and track volcanic ash clouds using GOES-12, the effectiveness of this capability will be diminished, especially during nighttime.

A Principal Component Image (PCI) was created using the 3.9 µm, 11 µm, and 12 µm infrared bands from the GOES-8 satellite and compared to a similar image generated from the 3.9 µm, 11 µm, and 13.3 µm bands from the GOES-12 satellite at 1445 UTC.

6.1 Update of Albedo Software for GOES-12

The software to generate both the shortwave albedo and day/night visible/shortwave albedo

The UTC covers the entire event, including the pre-storm conditions and all tornado reports For a detailed satellite interpretation of the event, please visit the following link: http://www.cira.colostate.edu/ramm/picoday/011010/011010.html.

6.3 NASA E-Theatre Premiere of GOES-12 Science Test 1-minute Imagery

The collaboration between NOAA/CIRA and the NASA Visualization and Analysis Laboratory has produced a High Definition Television (HDTV) version of the 1-minute imagery sequence from 9 October 2001, showcasing an anaglyph stereo view of tornadic thunderstorms in Kansas and Nebraska This stunning imagery was presented to enthusiastic audiences at two sold-out IMAX screenings at the Science Museum of Minnesota in St Paul, MN Additionally, NASA has requested further GOES-12 imagery, specifically including 4 km water vapor examples related to the tornadic storm event For more information, visit the NASA E-theatre Web page at http://etheater.gsfc.nasa.gov/index.html.

The success of the GOES-12 Science Test was significantly attributed to the contributions of various individuals, including Don Hillger, Gary Wade, and Tom Renkevins, who played key roles in daily coordination meetings to optimize the GOES-12 schedule for capturing relevant weather events Special acknowledgment is given to Gordon Moiles, Tina Baucom, and the entire GOES support team at SOCC for their efforts in establishing diverse schedules and sectors during the test, enabling the observation of various weather phenomena across different time and spatial scales Additionally, Pierre Leborgne from Meteo France contributed the simulation-based GOES-12 SST formula utilized in the analysis.

Anderson, G.P and Co-authors, 1999: MODTRAN4: Radiative Transfer Modeling for Remote Sensing Optics in Atmospheric Propagation and Adaptive Systems III, 3866, 2-10.

Daniels, J.M., T.J Schmit, and D.W Hillger, 2001: GOES-11 Imager and Sounder Radiance and Product Validations for the GOES-11 Science Test, NOAA Technical Report NESDIS 103, (August), 49 pp.

Ellrod, G.P., 2001: Loss of the 12.0 m “Split Window” Band on GOES-M: Impacts on Volcanic Ash Detection, 11 th Conf Sat Meteor Ocean., 15-18 October, Madison WI, 61-64.

Hillger, D.W., 2002: Changes in the GOES-12 Imager, CIRA Newsletter, 17, spring, 13-14.

Hillger, D.W., and J.D Clark, 2002: Principal Component Image analysis of MODIS for volcanic ash, Part-2: Simulations of current GOES and GOES-M Imagers, J Appl Meteor., 41, 1003-1010

Hillger, D.W., and T.H Vonder Haar, 1988: Estimating Noise Levels of Remotely Sensed Measurements from Satellites Using Spatial Structure Analysis J Atmos Oceanic Technol., 5, 206-214.

Ma, Xia L., T.J Schmit, and W.L Smith, 1999: A nonlinear physical retrieval algorithm—its application to the GOES-8/9 Sounder J Appl Meteor., 38, 501513.

Menzel, W P., and J F W Purdom, 1994: Introducing GOES-I: The first of a new generation of Geostationary Operational Environmental Satellites Bull Amer Meteor Soc., 75, 757-781.

Menzel, W.P., W.L Smith, and T.R Stewart, 1983: Improved cloud motion vector and altitude assignment using VAS J Climate Appl Meteor., 22, 377-384.

Menzel, W.P., F.C Holt, T.J Schmit, R.M Aune, G.S Wade, D.G Gray, and A.J Schreiner, 1998: Application of GOES-8/9 Soundings to weather forecasting and nowcasting Bull Amer. Meteor Soc., 79, 2059-2078.

Nieman, S., J Schmetz, and W.P Menzel, 1993: A comparison of several techniques to assign heights to cloud tracers, J Appl Meteor., 32, 1559-1568.

Schmetz, J., and K Holmlund, 1992: Operational cloud motion winds from Meteosat and the use of cirrus clouds as tracers Adv Space Res., 12, 95-104.

Schmit, T.J., E.M Prins, A.J Schreiner, and J.J Gurka, 2001: Introducing the GOES-M Imager.

Schmit, T.J., W.F Feltz, W.P Menzel, J Jung, A.P Noel, J.N Heil, J.P Nelson III, G.S Wade,2002: Validation and Use of GOES Sounder Moisture Information Wea Forecasting, 17, 139-154.

Schreiner, A.J and W.P Menzel, 2002: Comparison of Three Cloud Height Techniques using GOES-12 Imager Data Reprints, 6th Int Winds Workshop, Madison WI.

Weinreb, M.P., M Jamison, N Fulton, Y Chen, J.X Johnson, J Bremer, C Smith, and

J Baucom, 1997: Operational calibration of Geostationary Operational Environmental

Satellite-8 and -9 Imagers and Sounders App Opt., 36, 6895-6904.

Appendix A provides a collection of valuable websites related to the GOES-12 Science Test For schedules, visit the GOES-12 Science Test schedules page at CIRA To explore the contributions to the test results, check the RAMMT/CIRA results page Learn about the testing philosophy by accessing the dedicated page on GOES-12 For live imagery during the test period, the RAMSDIS OnLine (ROL) platform is available Current GOES-12 imagery can be found on the CIRA website, along with a JPEG archive of GOES-12 images Additionally, the CIRA Satellite page offers further insights into the satellite's operations.

Interpretation Discussion of GOES-12 Super Rapid Scan Operations (SRSO) during the 9 October 2001 Great Plains tornado event http://www.cira.colostate.edu/RAMM/PICODAY/011119/011119.html CIRA Satellite

The GOES-12 Imager underwent significant changes, including the loss of the 12µm band (channel 5) and the addition of the 13.3µm band (channel 6), which broadens the water vapor band to enhance data quality These modifications allow for better temperature and moisture retrievals, improved cloud-top pressure measurements, and more accurate sea surface temperature assessments The GOES-12 science test aims to investigate these enhancements by comparing its data with other satellites and analyzing the impact of the new spectral bands on product quality, ultimately improving meteorological observations and analyses.

Appendix B: Acronyms Used in this Report

ASOS Automated Surface Observing System

ASPT Advanced Satellite Products Team

AVHRR Advanced Very High Resolution Radiometer

AVIRIS Airborne Visible InfraRed Imaging Spectrometer

CART Cloud And Radiation Testbed

CICS Cooperative Institute for Climate Studies

CIMSS Cooperative Institute for Meteorological Satellite Studies CIRA Cooperative Institute for Research in the Atmosphere CONUS Continental United States

CSBT Clear Sky Brightness Temperature

FPDT Forecast Products Development Team

GOES Geostationary Operational Environmental Satellite GVAR GOES Variable (data format)

McIDAS Man-Computer Interactive Data Access System

MDB Match-up Data Base

MODIS Moderate Resolution Imaging Spectroradiometer

NASA National Aeronautics and Space Administration

NESDIS National Environmental Satellite, Data, and Information Service

NOAA National Oceanic and Atmospheric Administration

ORA Office of Research and Applications

ORAD Ocean Research and Applications Division

OSDPD Office of Satellite Data Processing and Distribution

OSO Office of Satellite Operations

PLOD Pressure-Layer Optical Depth

RAMMT Regional and Mesoscale Meteorology Team

RAMSDIS RAMM Advanced Meteorological Satellite Demonstration and Interpretation

RTTOVS Real Time TIROS Operational Vertical Sounder

SFOV Single Field Of View

SIT Soundings and Instrument Team

U PDATE OF A LBEDO S OFTWARE FOR GOES-12

The software to generate both the shortwave albedo and day/night visible/shortwave albedo

The UTC timeline encompasses the entire event, from the pre-storm conditions to the duration of all tornado reports For a detailed satellite interpretation of this event, please visit the following link: http://www.cira.colostate.edu/ramm/picoday/011010/011010.html.

6.3 NASA E-Theatre Premiere of GOES-12 Science Test 1-minute Imagery

The collaboration between NOAA/CIRA and the NASA Visualization and Analysis Laboratory has produced a high-definition television (HDTV) version of a 1-minute imagery sequence from 9 October 2001, showcasing an anaglyph stereo view of tornadic thunderstorms in Kansas and Nebraska This captivating imagery was featured in sold-out IMAX screenings at the Science Museum of Minnesota in St Paul, MN Additionally, NASA has requested further GOES-12 imagery, specifically 4 km water vapor examples related to the tornadic storm event For more details, visit the NASA E-theatre Web page at http://etheater.gsfc.nasa.gov/index.html.

The success of the GOES-12 Science Test was greatly influenced by numerous contributors, including Don Hillger, Gary Wade, and Tom Renkevins, who actively participated in daily coordination meetings to decide the optimal GOES-12 schedule for capturing significant weather events Special recognition is given to Gordon Moiles, Tina Baucom, and the entire GOES support team at SOCC for their efforts in coordinating the various GOES-12 schedules and sectors utilized during the test These schedules enabled the collection of diverse weather events across different time and spatial scales Additionally, Pierre Leborgne from Meteo France contributed the simulation-based GOES-12 SST formula used in the analysis.

Appendix A provides a list of valuable websites related to the GOES-12 Science Test For schedules of the GOES-12 Science Test, visit the CIRA RAMM site at [test schedules](http://www.cira.colostate.edu/ramm/goesm/test_schedules.htm) To explore the contributions to the test results, check out [test results](http://www.cira.colostate.edu/ramm/goesm/test_results.htm) For insights into the testing philosophy, refer to [testing philosophy and goals](http://www.cira.colostate.edu/ramm/goesm/testing_philosophy_goals.htm) Access live GOES-12 Science Test imagery through RAMSDIS OnLine at [ROL](http://www.cira.colostate.edu/RAMM/rmsdsol/goes12main.html) and view current imagery at [CIRA GOES-12 current imagery](http://www.cira.colostate.edu/Special/CurrWx/wxgoes12.htm) Additionally, the CIRA GOES-12 JPEG archive can be found at [jpeg archive](http://www.cira.colostate.edu/Infrastructure/Internet/GOES12Over.htm), and for satellite information, visit [CIRA Satellite](http://www.cira.colostate.edu/ramm/PICODAY/011010/011010.html).

The GOES-12 Imager has undergone significant changes, including the loss of the 12µm band (channel 5) and the introduction of a new 13.3µm band (channel 6), which broadens the water vapor band to enhance data quality These modifications aim to improve the accuracy of meteorological products such as temperature/moisture retrievals and cloud-top pressure measurements The Science Test for GOES-12 is designed to assess the quality of its data by comparing it with other satellites, and the results are expected to show better resolution and clarity in water vapor imagery Preliminary indications suggest that GOES-12 will perform comparably to previous models, particularly in fire detection capabilities.

NASA E-T HEATRE P REMIERE OF GOES-12 S CIENCE T EST 1- MINUTE I MAGERY

The collaboration between NOAA/CIRA and the NASA Visualization and Analysis Laboratory has produced a High Definition Television (HDTV) version of a 1-minute imagery sequence from 9 October 2001, showcasing an anaglyph stereo view of tornadic thunderstorms in Kansas and Nebraska This stunning imagery was presented to enthusiastic audiences at the Science Museum of Minnesota's IMAX theatre Additionally, NASA has requested further GOES-12 imagery, specifically 4 km water vapor examples related to the tornadic storm event For more details, visit the NASA E-theatre Web page at http://etheater.gsfc.nasa.gov/index.html.

The success of the GOES-12 Science Test was significantly influenced by numerous contributors, whose names are featured on the report's cover Key participants, including Don Hillger, Gary Wade, and Tom Renkevins, played vital roles in daily coordination meetings, making crucial decisions on the implementation of GOES-12 schedules to effectively capture daily weather events Special acknowledgment goes to Gordon Moiles, Tina Baucom, and the entire GOES support team at SOCC for their efforts in coordinating and establishing various GOES-12 schedules and sectors during the Science Test These schedules enabled the observation of diverse weather events across different time and spatial scales Additionally, Pierre Leborgne from Meteo France contributed the simulation-based GOES-12 SST formula utilized in Section 4.5.

Appendix A provides valuable resources related to the GOES-12 Science Test, including schedules, results, and testing philosophy For test schedules, visit [GOES-12 Science Test schedules](http://www.cira.colostate.edu/ramm/goesm/test_schedules.htm) Explore RAMMT/CIRA's contributions to the results at [test results](http://www.cira.colostate.edu/ramm/goesm/test_results.htm) and learn about the testing philosophy at [testing philosophy](http://www.cira.colostate.edu/ramm/goesm/testing_philosophy_goals.htm) Access live GOES-12 Science Test imagery through [RAMSDIS OnLine](http://www.cira.colostate.edu/RAMM/rmsdsol/goes12main.html) and view current imagery at [CIRA GOES-12 current imagery](http://www.cira.colostate.edu/Special/CurrWx/wxgoes12.htm) For archived JPEG images, check out [CIRA GOES-12 jpeg archive](http://www.cira.colostate.edu/Infrastructure/Internet/GOES12Over.htm) and find more satellite information at [CIRA Satellite](http://www.cira.colostate.edu/ramm/PICODAY/011010/011010.html).

The GOES-12 Imager has undergone two significant changes: the loss of the 12µm band (channel 5) and the addition of the 13.3µm band (channel 6), which broadens the water vapor band to 6.5µm These modifications enhance the quality and accuracy of satellite data, as the new bands allow for improved measurements of atmospheric conditions The GOES-12 science test aims to investigate data quality, produce real-time products, and assess the impact of these changes on current and new Imager products Preliminary results indicate that GOES-12 performs comparably to GOES-8 and significantly better than GOES-10 in fire detection capabilities.

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