# Presentation: 012316

## Landsat-5 TM and Landsat-7 ETM+ Performance Update

**LDCM Science Team Meeting**
**January 9, 2007**
- Brian Markham
**Landsat Calibration Scientist, NASA/GSFC  Landsat Project Science Office**
**Brian.L.Markham@nasa.gov**
**301-614-6608**

## Landsat Calibration Team

**James Storey****2****, Ron Hayes****2**** , Mike Choate****2****, Raj Rengarajan****2**
**Pat Scaramuzza****2****, Gyanesh Chander****2****, Esad Micijevic****2**
** ****Rynn Lamb****2****,** **Julia Barsi****3****, Dave Landis****3**** **
** ****Dennis Helder****4****, John Schott****5****, Simon Hook****6****, Kurt Thome****7****, and teams**

**Landsat Calibration Team**

**1**** LPSO, NASA/GSFC, * retired 01/03/07**
**2**** SAIC/EROS****
**3**** LPSO, SSAI/GSFC**
** ****4**** Image Processing Lab, South Dakota State University**
**5**** Center for Imaging Science, Rochester Institute of Technology**
**6 ****NASA/Jet Propulsion Lab**
**7**** Remote Sensing Group, University of Arizona**
**** Worked performed under ****U.S. Geological Survey contract 03CRCN0001**

## Landsat-7 ETM+ Geometric and Spatial Update

- Band-to-Band registration typically 0.05 pixels or better in line and scan direction (excluding band 6)
- MTF @ Nyquist changing consistent with pre-launch model--band 4 slightly below specification of 0.275
- Geodetic accuracy improved to < 20 m RMS since March 2005 Gyro 3 depowering (approx 1/3 pre 3/2005 values)
- Bumper mode transition expected during summer 2007

## Slide 4

## Landsat-5 TM Geometry Update

- Landsat-5 TM operating in bumper mode since 2002
- Monthly parameter updates
- Best geometric performance if data are ordered at least 1 month after acquisition (predicted versus refined parameters)
- Fixed array operations have introduced more uncertainty in spacecraft pointing knowledge
- We see larger and more frequent step corrections in the on-board attitude estimates
- Symptom of star updates correcting accumulated attitude error
- New processing logic was added to detect and correct the step offsets in the quaternion data

## Slide 6

## Landsat-7 ETM+ Reflective Band Radiometry Update

- Relative detector-to-detector normalization, i.e., striping less than ± 0.1%
- Between-date detector gain stable to < 3% over mission life (< 0.5%/year)
- Absolute radiometric accuracy better than ± 5%
- Noise stable over mission life
- Small improvement with SLC-off
- Anomalous coherent noise gone with SLC-off
- SLC failure had no significant impact on L7 ETM+ reflective band radiometry- continues to be excellent

## Landsat-7 ETM+ Thermal Band Radiometry Update

- Relative detector-to-detector normalization, i.e., striping less than ± 0.1%
- No observable change in instrument responsivity
- Absolute radiometric accuracy better than 1K
- Noise stable over mission life

## BLUE/GREEN: JPL data

- PINK/BROWN: RIT data

- BLACK: Historical recently processed Tahoe data
- PURPLE: recent Salton Sea

## Landsat-5 TM Reflective Band Radiometry Update

- Within-band within-scene internal stability
- Scan-Correlated Shift (SCS) of up to 0.7 DN
- Correctable with scan line-by-scan line background subtraction
- Memory Effect of up to 4 DN
- Currently corrected in NLAPS processing
- Some banding and striping issues remain to be resolved
- Between-date stability
- Interference cycling from icing on B5 and B7
- Correctable with IC processing or LUT that includes interference cycling
- Radiometric calibration processing
- Uses Gain Calibration History stored in Look-Up Table
- Extracts and applies biases on a scan line by scan line basis
- Rescaled to Fixed Radiance Range (LMIN, LMAX)
- Recently obtained datasets from ESA indicate calibration history can be improved
**Revised calibration LUT release planned for 3/5/2007**

## Proposed updated calibration curve in pink, tied to 1999 ETM+ cross-cal

**Notes:**
Band 2, pink curve anchored to L5 absolute gain from 1999 ETM+ cross call;  2004-2005 cal as determined by UAZ.
Note excellent agreement with 1999 cross cal point: 0.4%
Precision in UAZ cal point ~1.5%
Precision in 1999 cross-cal point based on Teillet paper is also around 1.5%
Again, two independent calibration agree very well.
Same comments regarding first two years of life—IC data of questionable use, initial DS data points may suggest steeper decay (Helder’s hypothesis, no on else agrees with!)

## Landsat-5 TM Thermal Band Radiometric  Calibration Update

- Sensitivity reduced by up to 50% by icing build-up on cold focal plane window
- Correctable with Internal Calibrator
- Current ground measurements show some bias compared to internal calibrator calibrated imagery
- Bias by +0.092 W/m2 sr m (~0.65K at 300K) for data processed beginning 3/5/2005
- Radiometric Calibration on Scene-by-Scene Basis using the response to the Internal Calibrator
- Rescaled to Fixed Radiance Range (LMIN, LMAX)
- Absolute accuracy ±2%

## Slide 13