Title :
The diurnal cycle of temperature and wind velocity and animal low-frequency calls
Author :
Garstang, Michael
Author_Institution :
Dept. of Environ. Sci., Virginia Univ., Charlottesville, VA
Abstract :
The effect of changes in near-surface atmospheric thermal stratification and wind velocity over a daily 24-h cycle upon the transmission of low-frequency animal calls is shown. The area ensonified changes from 30 km2 during the day to over 300 km2 in the early evening. The role of thermal stratification and fluctuations in wind velocity in governing these changes in transmission is discussed. Intranocturnal changes in the thermal and velocity fields of the atmosphere interrupt the optimum nighttime conditions with periods of poor acoustic conditions.
Keywords :
acoustic wave propagation; atmospheric acoustics; atmospheric boundary layer; atmospheric temperature; bioacoustics; Africa; Etosha National Park; Namibia; acoustic propagation; acoustics; animal call; animal calls; atmosphere; bioacoustics; boundary layer; diurnal cycle; diurnal variation; elephant; fluctuations; infrasound; intranocturnal changes; large mammal; low frequency sound; near-surface; night; nighttime; nocturnal atmosphere; temperature; thermal stratification; thermal structure; transmission; vocal communication; vocalisation; wind; wind velocity; Animals; Atmosphere; Auditory system; Ear; Fluctuations; Frequency; Pressure measurement; Temperature; Uncertainty; Wind speed;
Conference_Titel :
Geoscience and Remote Sensing Symposium, 2002. IGARSS '02. 2002 IEEE International
Print_ISBN :
0-7803-7536-X
DOI :
10.1109/IGARSS.2002.1025712
