In July, Google changed how its Flights tool calculates emissions to exclude all global warming impacts except CO2, understating flight emissions by nearly half (Justin Rowlatt/BBC)

Justin Rowlatt / BBC:
In July, Google changed how its Flights tool calculates emissions to exclude all global warming impacts except CO2, understating flight emissions by nearly half  —  The way Google calculates the climate impact of your flights has changed, the BBC has discovered.