# Can't get right temperature range after calculating land surface temperature

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08-20-2023 11:12 AM
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New Contributor II

Howdy! I've been trying to calculate the land surface temperature of Ghana by following exactly this post: https://www.gislounge.com/how-to-use-arcgis-pro-to-map-urban-heat-islands. I have used Band 4, Band 5 and Band 10 I downloaded from USGS. However, after using the following formulas and creating my LST outcome layer, I get weird extreme temperatures (61 to 91 degrees) and I don't understand why:

My formulas and values are:

1) Top of Atmosphere (TOA) = 0.00038*”B10.TIF”+0.1

2) Brightness Temperature (BT) = (1329.2405/Ln((799.0284/"TOA")+1))-273.15

K1_CONSTANT_BAND_10 = 799.0284

K2_CONSTANT_BAND_10 = 1329.2405, both from the metadata

3. NDVI = Float (band5-band4) / (band 5+band 4)

4. Proportional Vegetation (PV) = Square((“NDVI”+0.121068)/(0.459455+0.121068))

NDVI min is -0.121068

NDVI max is 0.459455, both from NDVI outcome layer

5. Error Correction / Emissivity (E) = 0.004* ”PV”+0.986

6. Land Surface Temperature (LST): (“BT”/(1+(0.00115*”BT”/1.4388)*Ln(“E”)))

By looking at the formulas above, could someone help poor me identify any issues? 🙁

I didn`t get any operation errors while running the different steps/formulas in the raster calculator, and have tried different things to correct that, including extract by mask tool as in this video where the guy got the same error: https://www.youtube.com/watch?v=EzavTBq-1wM&ab_channel=VikasGhadamode, but it didn't work for me.

Considerations: In the LST formula, I`m not sure if using 0.00115 is right, since I`m using Band 10. But I also tried to use 0.00106 as per below, but it wouldn't work either. Maybe there is a value wrong somewhere and I can't see it...

Band 10 TIRS 1 ---- 10.6 – 11.19

Band 11 TIRS 2 ---- 11.5 – 12.51

In case anyone is feeling super nice and wanna help me solve this mystery 😅, here's the link to download the files I'm using: https://we.tl/t-Pum2lyBqWU

Thank you so much - forever greatful 😎

Roger

Reference paper: Estimating Land Surface Temperature Using ArcGIS Any Help Contact Mr.Vikas Ghadamode--Vikasghadamode7@gmail.com WhatsApp Number= +918421031398 Special Thanks for What I am Using Software: https://amzn.to/3BO5IMF GIS BOOKS: https://amzn.to/3xmM333 Mic: https://amzn.to/3iYN77P HP ...
2 Replies
New Contributor

Hi Sturaro! Have you solved the issue? I am having the same problem with another city and the LST range seems very high.

New Contributor