> For the complete documentation index, see [llms.txt](https://cbe-berkeley.gitbook.io/clima/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cbe-berkeley.gitbook.io/clima/documentation/tabs-explained/outdoor-comfort.md). # Outdoor Comfort The **Outdoor Comfort** tab shows an overview of the perceived environmental condition based on the UTCI model. The [Universal Thermal Climate Index](http://www.utci.org/index.php) (UTCI), introduced in 1994, aims to be the measure of human physiological reaction to the atmospheric environment.

Graphical scheme of the UTCI calculation methodology

It considers: * dry bulb temperature * mean radiant temperature * wind speed * relative humidity to calculate a reference environmental temperature causing strain when compared to an individual's response to the real environment. It is based on [Fiala et al](https://link.springer.com/article/10.1007/s00484-011-0424-7).'s multi-node model of thermo-regulation. The [UTCI equivalent temperature](https://doi.org/10.1016/j.wace.2018.01.004) is a function of the above parameters, which are combined in a multinode thermo-physiological model that takes into account clothing insulation and metabolic rate. From this a[Universal Thermal Climate Index](http://www.utci.org/index.php) (UTCI) of perceived thermal stress is derived. **Clima** allows the user to visualize the annual UTCI equivalent temperature as heatmap under various environmental conditions.

Example: UTCI perceived temperature annual heatmap in 'Sun and Wind' conditions for Rome, ITA

The UTCI temperature can be converted in a scale assessing thermal stress, displayed by **Clima** in a heatmap graph.

Example: UTCI heat stress index heatmap in 'Sun and Wind' conditions for Rome, ITA

### Video Tutorial Learn more about the Outdoor Comfort tab by watching the following video. {% embed url="" %}