The results of experimental studies for the spatiotemporal structures of cloudiness emission in the LWIR (long-wave infrared) range using thermal imaging equipment are presented. Video streams with a minimum frequency of 50 Hz lasting more than 40 minutes, representing a sequence of digital thermal images for the sky fixed area, were used as initial data. In the process of studying, the spatiotemporal structures of cloudiness emission, time intervals (correlation radii) were estimated, the cross-correlation coefficients between frames of video streams being decreased from 1 to 0.5 during them. It has been established that for weather situations characterized by the cumulus cloudiness amount presence of (1–3) points, (4–6) points, and (7–9) points, the correlation radii are (45–75) s, (3–4) min and (5–6) min, respectively. For other types of atmospheric background (with altocumulus, cumulonimbus cloudiness and clear sky), the correlation radius exceeded the video recording time, i.e. such weather situations have a low rate of complete renewal for the cloudiness form.
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• LWIR range
• cross-correlation coefficient
• spatial structure of emission
• cloud atmosphere