PLANS FOR THE GOES-R SERIES AND COMPARING THE ADVANCED BASELINE

IMAGER (ABI) TO METEOSAT-8

UW-Madison

James J Gurka, Gerald J Dittberner

NOAA/NESDIS/OSD

Timothy J. Schmit,

NOAA/NESDIS/ORA

Mathew M. Gunshor, Kris Karnauskas

Cooperative Institute for Meteorological Satellite Studies (CIMSS)

Madison, WI

June, 2004Prague

2

GOES Users’ Conference I&II Recommendations: Instruments

– Strong Endorsements for Improved:

• Spatial resolution

• Spatial coverage

• Temporal resolution

• Spectral resolution

• Radiometric accuracy

NOTIONAL BASELINE DISTRIBUTED SATELLITE

ARCHITECTURE

NOTIONAL BASELINE DISTRIBUTED SATELLITE

ARCHITECTURE

– Advanced Baseline Imager (ABI)

– Hyperspectral Environmental Suite (HES)

– Solar Imaging Suite (SIS)

– Space Environmental In-Situ Suite

– GOES Lightning Mapper (GLM)

A-SatABISISGLMservice

B-SatHESSEISSservices

A-SatABISISGLMservices

B-SatHESSEISSservices

WEST EAST

The Advanced Baseline Imager:

ABI Current

Spectral Coverage 16 bands 5 bands

Spatial resolution 0.64 m Visible 0.5 km Approx. 1 kmOther Visible/nearIR 1.0 km n/aBands (>2 m) 2 km Approx. 4 km

Spatial coverageFull disk 4 per hour Every 3 hoursCONUS 12 per hour ~4 per hour

Visible On-orbit calibration Yes NoLow-light imaging Yes No

ABI spatial coverage rate versus the current GOES Imager

ABI coverage in ~5 minutes Current GOES coverage in 5 minutes

There are two anticipated scan modes for the ABI:1) full disk images every 15 minutes + CONUS images every 5 minutes +

mesoscale. 2) Full disk every 5 minutes.

Future GOES Imager (ABI) Band

Wavelength Range (μm)

Central Wavelength

(μm) Sample Objective(s)

1 0.45-0.49 0.47 Daytime aerosol-over-land, Color imagery 2 0.59-0.69 0.64 Daytime clouds fog, insolation, winds 3 0.84-0.88 0.86 Daytime vegetation & aerosol-over-water, winds 4 1.365-1.395 1.38 Daytime cirrus cloud 5 1.58-1.64 1.61 Daytime cloud water, snow 6 2.235 - 2.285 2.26 Day land/cloud properties, particle size, vegetation 7 3.80-4.00 3.90 Sfc. & cloud/fog at night, fire 8 5.77-6.6 6.19 High-level atmospheric water vapor, winds, rainfall 9 6.75-7.15 6.95 Mid-level atmospheric water vapor, winds, rainfall

10 7.24-7.44 7.34 Lower-level water vapor, winds & SO2 11 8.3-8.7 8.5 Total water for stability, cloud phase, dust, SO2 12 9.42-9.8 9.61 Total ozone, turbulence, winds 13 10.1-10.6 10.35 Surface properties, low-level moisture & cloud 14 10.8-11.6 11.2 Total water for SST, clouds, rainfall 15 11.8-12.8 12.3 Total water & ash, SST 16 13.0-13.6 13.3 Air temp & cloud heights and amounts

Current GOES ImagersMODIS, Aircraft, etc

ABI Bands

MSG/AVHRR/Sounder(s)

Based on experience from:

7

HES Sounder Capabilities

– Coverage: near full disk/ 1 hr• 10 km footprint

– Useful information 65 deg. from Sat. Sub. Point

– 4 km footprint in Meso/Severe Wx mode

– Rapid Scan option• 1000 x 1000 km in 4 minutes

– Will detect temperature inversions

– Will provide information in cloudy areas• Cloud top characteristics

• Temperature and moisture information above cloud tops

0.625cm-1 1.25cm-1 2.5cm-1

0.625 cm-1 0.625 cm-1

0.6 cm-1 0.6 cm-1

CO2

(T)

Important lines for cloud emissivity and cloud type

Ozone “Traditional Side of

H2O absorption”

CO2 weak H2OCO N2O Temperature

Example 2

Example 1

IR Spectral Coverage (DS or SW/M)

5

HES

HES’

Targeted observations -- look where we need the information

UW/NOAA

Sounder Comparison (GOES-Current to HES-Req)

Coverage Rate CONUS/hr Sounding Disk/hr

Horizontal Resolution

- Sampling Distance 10 km 10 km

- Individual Sounding 30-50 km 10 km

Vertical resolution ~3 km 1 km

Accuracy

Temperature 2 deg. K 1 deg. K

Relative Humidity 20% 10%

Current Requirement

Moisture Weighting Functions

Pre

ssur

e (h

Pa)

Pre

ssur

e (h

Pa)

Advanced Sounder

GOES (18)

1000 1000

100 100

UW/CIMSS

High spectral resolution advanced sounder will have more and sharper weighting functions compared to current GOES

sounder. Retrievals will have better vertical resolution.

GOES LIGHTNING MAPPERGOES LIGHTNING MAPPER• New NOAA Instrument

– Severe Storm Warning Times – Lightning Danger Alerts– Disaster Team Response– Nitrogen Production

• Detects Total Strikes:In Cloud, Cloud To Cloud, And Cloud To Ground– Compliments Today’s Land Based

Systems That Only Measures Cloud To Ground (About 15% Of The Total Lightning)

• Increased Coverage Over Oceans And Lands– Currently No Ocean Coverage,

And– Limited Land Coverage In Dead

Zones

• Parameters– Hemispheric Or CONUS Coverage

– 10 Km Spatial Resolution (1 Km Goal)

EUMETSAT and all are to be congratulated on the successful MET-8 program to a more robust geostationary imager.

Due to Met-8’s improved spectral, temporal and spatial data, Met-8 can be used to help prepare for the next generation U.S. geostationary imager.

If Met-8 is to be to for risk reduction activities for the Advanced Baseline Imager (ABI), then the similarities and differences of the data must be characterized.

Do to the varying center and spectral widths, some ABI/MET-8 bands are very similar, while others less so.

Parameter

Current GOES Imager

MET-8 Future GOES (ABI) Imager

Comments

Visible bands 1 2+1 3 Cloud cover, plant health and surface

features during the day

Near IR bands 0 1 3 Cirrus clouds, Low cloud/fog and fire

detection

Infrared bands 4 8 10 Upper-level water vapor, clouds, SO2,

SST, etc Total number

of bands 5 12 16

Coverage Rate 25 minutes for

full disk 15 minutes for

full disk

Approximately 5 minutes for full

disk

Noise (at 300K) in the IR window

0.15K - 0.10K

No correction has been made for the larger (approximately four times) of the current GOES imager compared to that

of the ABI Spatial

resolutions of the infrared

bands

4-8 km

3 km (with over-sampling)

2 km At the sub-satellite point

Low-light imaging

No No Yes

Comparing the GOES Imager, MET-8 and the ABI

The ABI visible and near-IR bands have many uses.

Visible and near-IR channels on the ABI

Visible and near-IR channels on the ABI

The current GOES has only one visible band.Haze

Cloud

sV

eg.

Cirrus

Part.

size

Snow

, Pha

se

AVIRIS spectra

While there are differences, there are also many similarities for the spectral bands on MET-8 and the Advanced Baseline Imager (ABI). Both the MET-8 and ABI have many more bands than the current operational imagers.

Weighting Functions for the IR channels on the ABI

Weighting functions for the standard atmosphere at a local zenith angle of 40 degrees.

Forward model calculations for the U.S. standard atmosphere (clear-sky) at nadir view comparing the ABI and MET-8

ABI/Met-8 Central wavelength (um)

3.9 3.9

6.19 6.27

6.95

7.34 7.35

8.5 8.7

9.61 9.67

10.35

11.2 10.76

12.3 11.9

13.3 13.3

ABI (K) 286.5 235.4 243.4 254.4 284.5 259.9 286.5 286.9 284.7 269.0 Met-8 (K) 283.9 235.8 254.4 284.3 260.8 286.3 285.6 267.6 ABI-Met-8 (K)

2.6 -0.4 - 0.0 0.2 -0.9 - 0.6 -0.9 1.4

These brightness temperature differences are not errors, just differences due to varying spectral widths and centers that should be understood.

ABI v. MSG – Visible, near-IR

Comparing the impact of spectral response differences for the 0.8 m, and 1.61 m bands from the Advanced Baseline Imager and the Meteostat Second Generation (MET-8) satellites is accomplished for the visilble bands by convolving the various spectral response functions with high spectral resolution AVIRIS (aircraft) data.

Below is a spectral plot of a clear and cloudy scene over the SCAR-B scene. 

ABI v. MSG – Visible, near-IR

The 0.6 and 1.6 m bands are very similar, while the 0.8 m band is more different between the two instruments due to the differing center wavelength.

ABI v. MSG – 0.8 m

ABI v. MSG – 1.6 m

MSG v. current GOES Imager – 4 m

AIRS data cannot be used to simulate the MSG 4 m band due to the wide spectral region coved by the MSG extends beyond the data for AIRS. So, a calculated spectra was used.

GOES-12 BT: 288.3K MSG BT: 284.5K GOES-MSG: 3.8K

GOES-12 and MSG 3.9 m SRF and night-time spectra.

ABI v. MSG – Some IR bands

Comparing the impact of spectral response differences for (some of) the IR from the Advanced Baseline Imager and the Meteostat Second Generation (MET-8) satellites can be accomplished by convolving the various spectral response functions with high spectral resolution AIRS (NASA satellite) data.

Below is a sample of a SRF at one AIRS spectra in the IR window region. 

Some bands can not be processed due to spectral gaps in the AIRS coverage. Of course the AIRS is coarser spatial resolution compared to the MET-8 or what ABI will be.

Below is a sample simulated from AIRS for the MET-8 IR window region.  This case is from March 19, 2004 at approximately 1:30 UTC.

11 um image

Some of these differences may be due to spectral gaps in the AIRS data.

7.3 m difference

Some of the difference between the convolved AIRS and forward calculations may be due to the amount of ozone

9.6 m difference

11 m difference

Fairly small differences

12 m difference

Fairly small differences—largest in warmer (clear) regions

13 m difference

Fairly large differences due to the varying spectral widths

Met-8 data -- displayed at SSEC

Summary

- Met-8 is leading the way with an advanced multi-spectral geostationary operational imager. Met-8 data will be used to prepare for the ABI.

- ABI and Met-8 have a number of similar bands, although due to spectral response differences, care must be taken when comparing the various bands.

- Some ABI/MET-8 bands are expected to be more similar (0.6, 7.35 and 8.7 m)

- While other ABI/MET-8 bands are expected to be somewhat different (0.8, 3.9 and 13.3 m)

- We look forward to the continuous nature of the high-spectral IASI instrument so more of the ABI bands can be simulated due to the removal of various spectral gaps.