Mapping Land Surface Temperature (LST) using Landsat-8 Imagery in ArcMAP
Land Surface Temperature (LST) refers to the temperature of the Earth’s surface as measured from above. It’s a crucial parameter in understanding the Earth’s energy balance and is utilized in various fields such as climate modeling, agriculture, urban planning, and environmental monitoring. [1]
LST is influenced by several factors including solar radiation, land cover type, soil moisture, and human activities. It’s typically measured using remote sensing techniques, primarily from satellites equipped with thermal infrared sensors. These sensors detect emitted thermal radiation from the Earth’s surface, allowing for the calculation of LST. [2]
LST helps in monitoring temperature variations across different regions anda times, and assessing the impact of human activities on the environment.
In this tutorial, we are going to estimating LST using Landsat 8 imagery.
Below are the formulas used to determine land surface temperature in Landsat-8.
- Top of Atmospheric (TOA) Spectral Radiance
2. Calculating top of atmosphere Brightness-temperature
3. Calculating NDVI — NDVI is used to quantify vegetation greenness and is useful in understanding vegetation density and assessing changes in plant health. NDVI is calculated as a ratio between the red (R) and near infrared (NIR) values in traditional fashion. In landsat-8, NIR values is in Band 5 and R values is in Band 4.
4. Calculating Proportion of Vegetation (PV)
5. Calculating Land Surface Emissivity (E)
6. Calculating Land Surface Temperature
Practice creating LST with Landsat 8 images in ArcMap
First of all download landsat-8 from https://earthexplorer.usgs.gov/. In this tutorial i use landsat-8 collection 2 level-1 with product id “LC08_L1TP_114064_20231016_20231102_02_T1” which located in South Sulawesi, Indonesia (path 114 — row 64).
After download the imagery, extract data in one folder. Open the metadata file, for mine it called LC08_L1TP_114064_20231016_20231102_02_T1_MTL.txt
Note down some important information regarding Band 10 which we will later use in calculations — look at TOA Spectral radiance and BT formula.
RADIANCE_MULT_BAND_10 = 3.3420E-04
RADIANCE_ADD_BAND_10 = 0.10000
K1_CONSTANT_BAND_10 = 774.8853
K2_CONSTANT_BAND_10 = 1321.0789
Load Band 10 into ArcMap software.
Now we have to calculating Top of Atmospheric (TOA) Spectral Radiance.
In the Arc Toolbox menu, select spatial analyst tools, Map Algebra, then select Raster Calculator.
In the Raster Calculator, write:
(0.000342*”LC08_L1TP_114064_20231016_20231102_02_T1_B10.TIF”)+0.1–0.29
Don’t forget to specify the folder location and output file name. I name it TOA_Radiance.TIF . After that, click Ok.
If you are confused, look again at the TOA spectral radiance calculation formula.
The result is shown below.
Now, we have to calculating top of atmosphere Brightness-temperature.
In the Arc Toolbox menu, select spatial analyst tools, Map Algebra, then select Raster Calculator.
In the Raster Calculator, write:
(1321.0789 / Ln ((774.8853/”TOA_Radiance.TIF”)+1))-273.15
Specify the folder location and output file name. I name it BT.TIF . After that, click Ok.
Next step is calculating NDVI so we have to load band 4 and band 5 data to Arc Map.
After both files loaded, rename them to make it easier.
Rename files:
LC08_L1TP_114064_20231016_20231102_02_T1_B5.TIF > Band 5 LC08_L1TP_114064_20231016_20231102_02_T1_B4.TIF -> Band 4
To calculate NDVI open Raster Calculator. In Raster Calculator write:
(Float(“BAND 5” — “BAND 4”)) / (Float(“BAND 5” + “BAND 4”))
Specify the folder location and output file name. I name it NDVI.TIF click Ok.
Pay attention to the formula for Calculating Proportion of Vegetation. We need the max and min values of NDVI. So don’t forget to note both. For mine, the maximum value is 0.620826 and minimum is -0.469875
To calculate Proportion of Vegetation (PV), open raster calculation and write:
Square((“NDVI.TIF”+0.469875) / (0.620826 + 0.469875))
Specify the folder location and output file name. I name it PV.TIF click Ok.
Now, we have to calculate the land surface emissivity from proportion vegetation value. Open raster calculation and write:
0.004 * “PV.TIF” + 0.986
Specify the folder location and output file name. I name it Emissivity.TIF click Ok.
And the last step is to calculate Land Surface Temperature (LST). Open raster calculation, and write:
“BT.TIF” / (1 + (10.895 * “BT.TIF” ) / 14388 * Ln (“Emissivity.TIF”))
The result is shown below.
Then i open the area of interest (AOI) called Tallo Watershed. After that I cut the LST calculation results according to the AOI.
The last step is layout your LST Map!
If you pay attention, the LST value is quite high — above 35 degrees Celsius, this is most likely due to the influence of the El Nino phenomenon.
Hope this tutorial help you! Thanks you!
Reference:
[1] Kumar, Ajay & Nirala, Bikaram & Roushan, Rupesh. (2023). Literature Survey for Land Surface Temperature Using Parameters that Include the Normalised Differential Vegetation Index and the Impervious Surface Area. 2. 20–26. 10.5281/zenodo.8238736.
[2] He, Juelin & Zhao, Wei & Li, Ainong & Wen, Fengping & Yu, Daijun. (2018). The impact of the terrain effect on land surface temperature variation based on Landsat-8 observations in mountainous areas. International Journal of Remote Sensing. 40. 1–20. 10.1080/01431161.2018.1466082.
[3] Eboy OV, Kemarau RA. Study Variability of the Land Surface Temperature of Land Cover during El Niño Southern Oscillation (ENSO) in a Tropical City. Sustainability. 2023; 15(11):8886. https://doi.org/10.3390/su15118886
[3]USGS (2019) Landsat 8 (L8) Data Users Handbook. LDSD-1574, Version 5.0. 114 p.
https://www.usgs.gov/landsat-missions/landsat-8-data-users-handbook
[4] Avdan, Uğur and Gordana Jovanovska. “Algorithm for Automated Mapping of Land Surface Temperature Using LANDSAT 8 Satellite Data.” J. Sensors 2016 (2016): 1480307:1–1480307:8.
[5]Landsat 8 OLI and TIRS Calibration Notices https://www.usgs.gov/landsat-missions/landsat-8-oli-and-tirs-calibration-notices
