This dataset includes the lifetimes of polluted cloud tracks identified from geostationary MSG SEVIRI satellite data.

Additional information
Jorma Rahu jorma.rahu@ut.ee
Velle Toll velle.toll@ut.ee

This work is funded by the Estonian Research Council personal research funding grants PSG202 and PRG1726.
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DATASET
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The dataset contains the datetime and location information for the identified polluted cloud tracks. 
For each location geographical latitude and longitude is given. All tracks have been hand-logged
at various industrial sites and cities in Eastern Europe.
Both start and end times with calculated total lifetime are presented. Also the cloud conditions
for when tracks appear and dissapear are described.

The dataset can be used to study the lifetime of polluted cloud tracks.

Creators: Jorma Rahu, Velle Toll
Organisation: University of Tartu
Rights-holder: University of Tartu
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TERMS OF USE
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Copyright 2023 University of Tartu. 
This dataset is licensed by the rights-holder under a Creative Commons Attribution 4.0 International Licence: https://creativecommons.org/licenses/by/4.0/.
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CONTENTS
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The file Lifetime_data.csv contains the full data-set.
Columns in the file are as follows:
Date of polluted cloud track occurence, Day-of-Year, track location (city name), location coordinates (lat-lon),
track start timestamp, track end timestamp, calculated track lifetime, track start conditions, track end condition.

Track_start_condition options and meanings:
0	Tracks appear within 15 minutes when suitable clouds appear
1	Tracks appear when suitable clouds are already present for at least 30 minutes
2	Track appear directly after upper layer clouds pass
	
Track_end_condition options and meanings:
0	Suitable clouds present, track dissapears
1	Cloudcover dissapears completely
2	Track visibility hindered by upper layer clouds
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METHODS and PROCESSING
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Polluted cloud tracks were initially identified using near-infrared composite MODIS Terra satellite 
images from National Aeronautics and Space Administration (NASA) Global Imagery Browse Services.
For the dates where visible cloud tracks were seen, we manually processed higher temporal resolution
geostationary MSG SEVIRI satellite images to find the exact timestamps the tracks become visible and
when they dissapear. From these timestamps the lifetime can be calculated for every single track case.
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