Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera

Ground-based cloud detection at nighttime is achieved by using cameras, lidars, and ceilometers. Despite these numerous instruments gathering cloud data, there is still an acknowledged scarcity of information on quantified local cloud cover, especially at nighttime. In this study, a digital camera i...

Full description

Saved in:
Bibliographic Details
Main Authors: Gacal, Glenn Franco Barroso, Antioquia, Carlo, Lagrosas, Nofel
Format: text
Published: Archīum Ateneo 2016
Subjects:
Online Access:https://archium.ateneo.edu/manila-observatory/5
https://pubmed.ncbi.nlm.nih.gov/27505386/
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Ateneo De Manila University
id ph-ateneo-arc.manila-observatory-1005
record_format eprints
spelling ph-ateneo-arc.manila-observatory-10052022-05-06T07:34:13Z Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera Gacal, Glenn Franco Barroso Antioquia, Carlo Lagrosas, Nofel Ground-based cloud detection at nighttime is achieved by using cameras, lidars, and ceilometers. Despite these numerous instruments gathering cloud data, there is still an acknowledged scarcity of information on quantified local cloud cover, especially at nighttime. In this study, a digital camera is used to continuously collect images near the sky zenith at nighttime in an urban environment. An algorithm is developed to analyze pixel values of images of nighttime clouds. A minimum threshold pixel value of 17 is assigned to determine cloud occurrence. The algorithm uses temporal averaging to estimate the cloud fraction based on the results within the limited field of view. The analysis of the data from the months of January, February, and March 2015 shows that cloud occurrence is low during the months with relatively lower minimum temperature (January and February), while cloud occurrence during the warmer month (March) increases. 2016-01-01T08:00:00Z text https://archium.ateneo.edu/manila-observatory/5 https://pubmed.ncbi.nlm.nih.gov/27505386/ SOSE Affiliate: Manila Observatory Archīum Ateneo Oceanography and Atmospheric Sciences and Meteorology
institution Ateneo De Manila University
building Ateneo De Manila University Library
continent Asia
country Philippines
Philippines
content_provider Ateneo De Manila University Library
collection archium.Ateneo Institutional Repository
topic Oceanography and Atmospheric Sciences and Meteorology
spellingShingle Oceanography and Atmospheric Sciences and Meteorology
Gacal, Glenn Franco Barroso
Antioquia, Carlo
Lagrosas, Nofel
Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera
description Ground-based cloud detection at nighttime is achieved by using cameras, lidars, and ceilometers. Despite these numerous instruments gathering cloud data, there is still an acknowledged scarcity of information on quantified local cloud cover, especially at nighttime. In this study, a digital camera is used to continuously collect images near the sky zenith at nighttime in an urban environment. An algorithm is developed to analyze pixel values of images of nighttime clouds. A minimum threshold pixel value of 17 is assigned to determine cloud occurrence. The algorithm uses temporal averaging to estimate the cloud fraction based on the results within the limited field of view. The analysis of the data from the months of January, February, and March 2015 shows that cloud occurrence is low during the months with relatively lower minimum temperature (January and February), while cloud occurrence during the warmer month (March) increases.
format text
author Gacal, Glenn Franco Barroso
Antioquia, Carlo
Lagrosas, Nofel
author_facet Gacal, Glenn Franco Barroso
Antioquia, Carlo
Lagrosas, Nofel
author_sort Gacal, Glenn Franco Barroso
title Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera
title_short Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera
title_full Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera
title_fullStr Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera
title_full_unstemmed Ground-Based Detection of Nighttime Clouds Above Manila Observatory (14.64°N, 121.07°E) Using a Digital Camera
title_sort ground-based detection of nighttime clouds above manila observatory (14.64°n, 121.07°e) using a digital camera
publisher Archīum Ateneo
publishDate 2016
url https://archium.ateneo.edu/manila-observatory/5
https://pubmed.ncbi.nlm.nih.gov/27505386/
_version_ 1733052866860417024