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DNB Terrain CorrectionSlide Fire, AZ

Part 2William Straka III

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Background

• IDPS Mx8.4 was implemented on 22 May, 2014 starting with the ~14:40 GMT observation time.

• One of the key features is Terrain Correction is implemented for the Day Night Band– The TC latitude/longitudes are variables in the GDNBO files and not a separate

file.– This means thermal, NIR and DNB emissive sources should now match up in all

regions

• NDE provided test case over Iceland as so users could adjust their scripts/code accordingly. We wish to acknowledge their help in this– The nightly McIDAS-V was ready before (21 May 2014) the TC navigation was

available within the GDNBO files.

Test case

• Test case is the Slide Fire in Arizona– Cases from 24-26 May are shown– 24 May 2014 is near nadir, others progress to the

left of the scan• Arrow is located at roughly an edge in the the

M13 band (terrain corrected) and in the same place for all images for a given time stamp

• Some slides have animations, so use slide show

24 May 2014, 0914ZM13 – 3.9mm

Slide

24 May 2014, 0914ZM10 – 1.6mm

24 May 2014, 0914ZDNB – NonTC

24 May 2014, 0914ZDNB –Terrain Corrected

24 May 2014, 0914ZDNB non-TC, M10, M13

24 May 2014, 0914ZDNB_TC, M10, M13

25 May 2014, 0855ZM13 – 3.9mm

Slide

25 May 2014, 0855ZM10 – 1.6mm

24 May 2014, 0914ZDNB – NonTC

25 May 2014, 0855ZDNB –Terrain Corrected

25 May 2014, 0855ZDNB non-TC, M10, M13

25 May 2014, 0855ZDNB_TC, M10, M13

26 May 2014, 0835ZM13 – 3.9mm

Slide

26 May 2014, 0835ZM10 – 1.6mm

26 May 2014, 0835ZDNB – NonTC

26 May 2014, 0835ZDNB –Terrain Corrected

26 May 2014, 0835ZDNB non-TC, M10, M13

26 May 2014, 0835ZDNB_TC, M10, M13

Observations

• All three scenes are cloud free

• As can be seen the non-terrain corrected geolocated DNB image of Slide Fire is clearly shifted from the M10 and M13, both which are terrain corrected, hot spots to varying degrees

• The terrain corrected DNB geolocation shifts the fire inline with the hot spots indicated in the M10 and M13 band data

Conclusions

• These three cases show the amount of variation in the non-terrain corrected data, depending on what part of the scan the fire is located.– Largest shift is when it is on the edge of scane.

• It appears that the Terrain Corrected navigation correctly shifts fires in-line with thermal observations.

• Based on this, McIDAS-V 1.5 beta appears to correctly use the terrain corrected navigation, if it is available. – In addition it is backward compatible to data without the TC navigation.