Publication Type

Journal Article

Version

acceptedVersion

Publication Date

4-2020

Abstract

Land surface temperatures (LST) in urban landscapes are typically more heterogeneous than can be monitored by the spatial resolution of satellite-based thermal infrared sensors. Thermal sharpening (TS) methods permit the disaggregation of LST based on finer-grained multispectral information, but there is continued debate over which spectral indices are most appropriate for urban TS, and how they should be configured in a predictive regression framework. In this study, we evaluate the stability of various TS kernels with respect to LST at different spatial (Landsat 8) and diurnal (MODIS) scales, and present a new TS method, global regression for urban thermal sharpening (SGRUTS), based on these findings. Of the spectral indices examined, the normalized difference built-up index (NDBI) and the normalized multi-band drought index (NMDI) were the most spatially stable for Landsat 8 and MODIS overall. Kernel performance varied diurnally, with the index-based impervious surface index (IBI) and broadband α selected for 1030 h, NDBI and NMDI selected for 1330 h, and IBI and NMDI selected for 2230 h and 130 h, respectively. Over a range of field-validated metrics, the SGRUTS scheme comprising a two-factor interaction between NDBI and NMDI was competitive with the best alternative TS models compared. This SGRUTS model is essentially a refinement of the Enhanced Physical Method for urban applications in terms of kernel selection and configuration, and has interpretative advantages over more complex statistical schemes.

Keywords

Impervious surface, Normalized differences, Regression method, Spatial resolution, Statistical scheme, Thermal infrared sensors, Urban applications, Urban land surface temperature

Discipline

Environmental Sciences | Political Science | Urban Studies and Planning

Research Areas

Political Science

Publication

International Journal of Remote Sensing

Volume

41

Issue

8

First Page

2986

Last Page

3009

ISSN

0143-1161

Identifier

10.1080/01431161.2019.1697009

Publisher

Taylor & Francis

Copyright Owner and License

Authors

Additional URL

https://doi.org/10.1080/01431161.2019.1697009

Share

COinS