Enlarge / A view of wildfires at Lebel-sur-Quevillon in Quebec, Canada on June 23, 2023. (credit: REDERIC CHOUINARD /SOPFEU / Handout/Anadolu Agency via Getty Images )

This article originally appeared on Inside Climate News , a nonprofit, independent news organization that covers climate, energy, and the environment. It is republished with permission. Sign up for their newsletter here .

June 2023 may be remembered as the start of a big change in the climate system, with many key global indicators flashing red warning lights amid signs that some systems are tipping toward a new state from which they may not recover.

Earth’s critical reflective polar ice caps are at their lowest extent on record in the satellite era, with the sea ice around Antarctica at a record-low extent by far, spurring worried scientists to share dramatic charts of the missing ice repeatedly. In the Arctic, the month ended with the Greenland Ice Sheet experiencing one of the largest June melt events ever recorded , and with scientists reporting that June 2023 was the hottest June ever measured, breaking the 2019 record by a “staggering” 0.16° Celsius.

Enlarge (credit: Damien Meyer/Getty Images)

Flying premium from San Francisco to Los Angeles, a common trip for some Californians, could generate 101 kilograms of carbon emissions, or perhaps 142 or even 366 kilograms—depending on what source you search online.

The wide range of estimates stems from what some climate experts view as a growing problem, with Google at the center. More people are trying to factor climate change impacts into life choices such as where to vacation or what to eat. Yet scientists are still debating how to accurately estimate the impacts of many activities, including flying or producing meat. While the math gets sorted out, some industries decry emissions estimates as unfair.

Google has led the way among Big Tech companies in trying to inform users about their potential carbon footprint when traveling, heating their homes, and, as of recently, making dinner. But airlines, cattle ranchers, and other industry groups are pushing back, saying Google’s nudges could hurt their sales. They have demanded—successfully, in the case of airlines—that the search giant rethink how it calculates and presents emissions data.