Google Flights Changes to Emissions Calculations Stir Controversy

If you are searching Google Flights to decide on a New York to London roundtrip in mid-September, and you want to book the flight with the lowest nasty impact to climate change, you might opt for a Virgin Atlantic, Air France-Delta-KLM trip because its CO2 emissions are estimated to be 26 percent lower than what's typical for the route while the JetBlue flights might exceed the routine climate wallop by 14 percent.

However, your choice could potentially be wrong from a climate change perspective because earlier this summer Google stopped including the impact of contrails — those ice cloud trails behind the aircraft that trap heat but look pretty as jets disappear from view across the skies. Scientists say that the adverse environmental impact and global warming affects of contrails may be just as great, if not greater, than CO2 emissions.

Google eliminated contrail data from its emissions calculations after engaging with academics who counseled that the science of measuring the contrail impact from specific flights isn't precise. And the adverse impact impact of contrails can vary widely depending on whether it's a dayt