Streaming: Assumes viewing via a laptop using an external monitor. Streaming includes device use, data centre and network transmission estimates by the International Energy Agency. World average (2019) CO2/kwh for electricity is used.
Shipping: Assumes ground shipments via non-refrigerated heavy goods vehicle (diesel-powered), 100%-laden. Carbon factor for air shipments is adjusted to account for short-haul (<3,700km) and long-haul flights based on the shipping distance entered. (DEFRA, 2019)
Pre-production: Low-production recording assumes recorded interview via a Zoom-style platform where two individuals are using a laptop and external monitor set-up. High production recording assumes professional studio use with lighting and sound using a small crew, including some travel. (Albert, 2019)
Materials use: Lifecycle impacts of gifts and production materials are not included. (This is possible to add through a custom calculation.)
Footprint comparisons:
Latte: Carmen Nab, Mark Maslin (2020)
Hotel stay: Hotel Carbon Footprinting Tool (2019)
Flights, Driving: DEFRA (2019)
Home electricity: USEPA (2018)/IEA (2019)
U.S. resident: Our World In Data (2019)