Status for: Land Surface Temperature and Emissivity (MOD21)

 
General Accuracy Statement

Stage 2 validation has been achieved for the MYD21 Collection 6 LST&E products.

The MYD21 (MODIS-Aqua) Collection 6 (C6) LST&E products have been validated to Stage 2 status using a combination of Temperature and Radiance-based methods over a global set of sites in the USA, China, Spain, Portugal, and Southern Africa.

The results summarized in Table 1 and Figure 1 show that the MYD21 C6 LST products have an average root mean square error (RMSE) of 1.33 K with negligible bias and accuracies independent of land cover type. The heritage MYD11 C6 LST products have an average RMSE of 2.32 K and show large biases (3-5 K) over dryland regions due to an overestimation of emissivity in the longwave bands documented in several studies [Malakar et al., 2016; Li et al., 2020; Hulley and Cook, 2020]. The MYD21 C6 emissivity spectra had an average accuracy of 1.31% for all TIR bands (29, 31, 32) when compared to lab measured spectra at six pseudo-invariant sites shown in Figure 2.

The MOD21 (MODIS-Terra) LST&E products have yet be fully validated since they were affected by the band 29 crosstalk calibration issue apparent in C6, and were only produced up to 2005 as a result. This issue has been addressed in C6.1 with updated calibration coefficients and all MOD21 products are currently in reprocessing with expected release in Spring 2021.

LST Val MOD21 table
Table 1. A summary of MODIS MYD21 and MYD11 LST validation results of studies where the validation was performed
for both products simultaneously, i.e. one to one validation comparison with in-situ data

LST Val MOD21 table
Figure 1. Summary of LST validation of the MYD21 and MYD11 C6 products from 2002-2018 using a combination of
Temperature-based and Radiance-based validation methods at two water, two vegetated, and six pseudo-invariant sand dunes sites in the U.SA [1, 6].

LST Val MOD21 table
Figure 2. Emissivity spectra comparisons between the MOD21 and MOD11 products and lab measurements of sand
samples collected at six pseudo-invariant sand dune sites in the USA.

Details of MxD21 C6 LST&E validation practices can be found in the MxD21 ATBD here https://modis.gsfc.nasa.gov/data/dataprod/mod21.php and in Malakar et al. 2016.


Product status updated:  February 2021
Product version:  Collection 61
 
Supporting Studies:

Title: Temperature-Based and Radiance-Based Validation of the Collection 6 MYD11 and MYD21 Land Surface Temperature Products Over Barren Surfaces in Northwestern China
Author: Li, H., Li,R., Yang,Y., Cao,B., Bian,Z., Hu,T., Du,Y., Sun, L., and Liu, Q
Source: IEEE, 2021, 59(2)
View Abstract and Access Publication
 
Title: A Water Vapor Scaling Model for Improved Land Surface Temperature and Emissivity Separation of MODIS Thermal Infrared Data, Remote Sensing of Environment
Author: Malakar, N.K. and G. C. Hulley
Source: Remote Sensing of Environment, Volume 182, 252-264
View Abstract and Access Publication
 
Title: Test of the MODIS Land Surface Temperature and Emissivity Separation Algorithm With Ground Measurements Over a Rice Paddy
Author: Coll, C., Garcia-Santos, V., Niclos,R., and Caselle, V.
Source: IEEE, 2016, 54 (5)
View Abstract and Access Publication
 
Title: Thermal-based techniques for land cover change detection using a new dynamic MODIS multispectral emissivity product (MOD21)
Author: Hulley, G., S. Veraverbeke, S. Hook
Source: Rem. Sens. Environ, 140, p755-765
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Title: Validation of remotely sensed surface temperature over an oak woodland landscape - The problem of viewing and illumination geometries
Author: Ermida, S.L., Trigo, I. F., DaCamara, C. C., Gottsche, F. M., Olesen, F. S., and Hulley, G.
Source: Remote Sensing of Environment 148 (2014) 16-27
View Abstract and Access Publication
 
Title: Quantifying Uncertainties in Land Surface Temperature (LST) and Emissivity Retrievals from ASTER and MODIS Thermal Infrared Data
Author: Hulley, G. C., T. Hughes, and S. J. Hook
Source: J. Geophys. Res. Lett, 117, D23113, doi:10.1029/2012JD018506
View Abstract and Access Publication
 
Title: A radiance-based method for estimating uncertainties in the Atmospheric Infrared Sounder (AIRS) land surface temperature product
Author: Hulley, G. C., and S. J. Hook
Source: J. Geophys. Res. Lett, 117, D20117, doi:10.1029/2012JD019102
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Title: MODIS MOD21 Land Surface Temperature and Emissivity Algorithm Theoretical Basis Document
Author: Hulley, G., Hook, S., and Hughes, C.
Source: JPL Publication 12-17
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Title: Generating Consistent Land Surface Temperature and Emissivity Products Between ASTER and MODIS Data for Earth Science Research
Author: Hulley, G. C., and S. J. Hook
Source: IEEE Trans. Geos. Rem. Sens., DOI: 10.1109/TGRS.2010.2063034
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Title: Validation of the North American ASTER Land Surface Emissivity Database (NAALSED) version 2.0 using pseudo-invariant sand dune site
Author: Hulley, G. C., S. J. Hook, and A. M. Baldridge
Source: Remote Sens. Environ, 113, 2224-2233
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Title: Intercomparison of Versions 4, 4.1 and 5 of the MODIS Land Surface Temperature and Emissivity Products and Validation with Laboratory Measurements of Sand Samples from the Namib Desert, Namibia
Author: Hulley, G.C., Hook, S.J.
Source: Remote Sensing of Environment 113 (2009) 1313-1318
View Abstract and Access Publication