# QSSI (QGIS summer simmer index) calculator plugin: an open-source tool for thermal comfort analysis in gis applications

## TL;DR

The QSSI plugin for QGIS helps map summer thermal stress in urban areas, showing that most residents in Adana face high heat risks.

## Contribution

The QSSI plugin integrates the Summer Simmer Index into QGIS for direct spatial thermal stress analysis.

## Key findings

- Over 80% of Adana's urban population is exposed to high thermal stress during summer.
- The plugin enables spatially explicit bioclimatic stress mapping within QGIS.
- The tool supports climate adaptation and urban heat management decisions.

## Abstract

Thermal stress, driven by the combined influence of high temperature and humidity, has become a critical public health concern in rapidly urbanizing Mediterranean cities. This study introduces the QGIS Summer Simmer Index (QSSI) Calculator, an open source plugin developed in Python and Qt Designer to provide fast and reproducible mapping of summer thermal stress. The tool integrates the Summer Simmer Index (SSI) directly into the QGIS environment, enabling users to generate spatially explicit bioclimatic stress maps without relying on external modeling platforms. Adana was selected as the pilot area due to its prolonged hot and humid summer conditions. The results indicate that more than 80% of the urban population is exposed to Hot or Very Hot SSI classes during the summer season, highlighting significant risks for nearly 1.8 million residents. These findings demonstrate the plugin’s value as a practical spatial decision support tool for climate adaptation and urban heat management. Future versions will incorporate additional environmental variables to improve model detail and broaden applicability.

The online version contains supplementary material available at 10.1007/s00484-026-03180-x.