SpeakUp! – The effects of temperature and altitude on speech and articulation

Funded by: Free University of Bozen, Faculty of Education​

Project duration: 2018 – 2020​


The aim of this project is to study the effect of environmental factors such as temperature, humidity, pressure, or oxygen level on speech.

Many aspects of speech are determined by physiological characteristics (e.g. size of vocal tract, age), but there are also situational factors, such as different kinds of stress (e.g. background noise, cognitive work load, emotion). One of the less studied factors that might induce stress and affect speech are environmental factors like temperature, humidity or atmospheric pressure. Some studies have looked at the effect of humidity and temperature on vocal fold activity in terms of phonation threshold pressure or phonatory effort which can be related to voice quality.

However, less is known how these factors affect supraglottal articulation and general speech patterns. For example, cooling of muscles through exposure to cold air affects physical performance, particularly fast movements, which might consequently affect the ability to control lip, jaw or even tongue movement. Speakers might also adapt their articulation patterns to prevent too much cold or dry air to enter the vocal tract and affect the vocal folds.

Although not much is known about the direct effect of environmental factors on speech, several studies have drawn connections between geographic or climatic factors and phonological inventories of languages based on typological information obtained in data bases, claiming that over a course of time some environments might be more likely to give rise to certain phonologic features.

The project will explore how speakers react to different environmental factors by analyzing acoustic and articulatory data and contribute to the existing research on mechanisms responsible for language variation.

Project Members

Alessandro Vietti

Lia Saki Bučar Shigemori


Bučar Shigemori, L. S. and Vietti, Alessandro 2019. Acoustic analysis of Italian singleton/geminate stop production in two ambient temperature conditions. In Sasha Calhoun, Paola Escudero, Marija Tabain & Paul Warren (eds.) Proceedings of the 19th International Congress of Phonetic Sciences, Melbourne, Australia 2019 (pp. 3676-3680). Canberra, Australia: Australasian Speech Science and Technology Association Inc. [PDF]