Weekly Report on GOES-14 PLT Science Test

1
Weekly Report onGOES-14 PLT Science Test

• NOAA / NESDIS / STAR
• X. Wu, G. Rancic, F. Yu, M. Grotenhuis
• December 14, 2009

2
Initial Post-Launch Calibration ofGOES-14 Imager
Visible Channel by Moon

• Purpose
• Verify pre-launch calibration
• Establish benchmark for trending
• Method
• Vicarious calibration based on lunar
  observations.
• Data
• GOES-14 lunar observations on 08/10/2009.
• Analysis
• Lunar irradiances are calculated per Wu Yu
  (2006).
• ROLO predicted irradiances are obtained (courtesy
  of Dr. Tom Stone of USGS).

3
GOES-14 observed and ROLO model predicted lunar
irradiances and their ratios
3. The ratio is not constant, likely due to
angular dependence of scan mirror reflectance
that will be addressed separately.
2. The measured irradiance generally follows the
predicted trend.
1. The predicted lunar irradiance decreases with
the waning moon
4
Preliminary results

• The GOES-14 Imager visible channel appears 1
  brighter than predicted by the ROLO model.
• Well within the uncertainty of Lunar based
  post-lunch calibration (gt2).
• It has been observed for several AVHRRs that
  measurements are initially brighter then
  expected.
• Further evaluation by other vicarious calibration
  will follow.