A regional seminar for 200 people accounts for about 15 to 40 tCO2e, and a national conference with 500 to 800 participants for 80 to 200 tCO2e. A trade show with several thousand visitors can reach 400 to 1,500 tCO2e. An international conference dominated by flights exceeds 500 tCO2e, sometimes 2,500 tCO2e, and a public festival lies between 2,000 and 15,000 tCO2e depending on the share of local attendees. The footprint per participant varies by a factor of 10 between a local seminar and an international conference, almost entirely because of transport.
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