Data shows Las Vegas hot streak made five times more likely due to climate change

LAS VEGAS (KTNV) — We all know it gets hot here in Las Vegas, but this recent weather has taken that heat to a new level.

On Sunday, when the thermometer at Harry Reid hit 120 degrees, it shattered an all-time temperature record of 117. Beyond that, daily high records fell Sunday, Monday and Tuesday amid this hot streak.

To learn more about what’s fueling these extreme temperatures, I spoke with Climate Central Meteorologist Shel Winkley, who said it's possible to measure how much climate plays a role.

"It is summer time. You are in the desert so you do expect hot temperatures. But look at the all time record that happened on Sunday. Right? That's not a normality," Winkley said. “In a weather pattern with big, intense, high pressure like this, it would have been hot because it's Las Vegas. But we know that the extreme temperatures and the record temperatures that are being felt have been made at least five times more likely due to human-induced climate change."

A tool called the Climate Shift Index reflects this figure. The data analysis, which you can access here, is based on the ratio of the local frequency of a particular daily temperature in the current climate to the estimated frequency in a climate without known fossil fuel emissions.

“So what we do is we take 22 different climate models and we'll work it two ways. One, we'll run it with the historical greenhouse gas emissions 22 times over to get a frequency. And then, we'll run it 22 times over without adding those carbon emissions, the historical carbon emissions, and what we can do is we can take a ratio against the 30-year average to understand how much of this is human caused and how much of this is just weather."

Winkley said that the index shows the latest record-breaking temperatures in Las Vegas would be highly unlikely without the historic influence of greenhouse gases.

“So what we know from pre-industrial times, we've added about 50% more carbon, CO2, to the atmosphere and we've added about 160% as much methane to the atmosphere and those are greenhouse gases. So what they do is, like a greenhouse, they trap in the heat that gets absorbed into the earth from the sun's rays. Carbon is a natural element of our atmosphere, but we're adding an exceptional amount that the earth can't regulate."

NASA Visualization Studio

This year, not only are cities like Las Vegas breaking all-time records, but other things like ocean temperatures and the earth’s surface are trending hotter.

“Yes. It is supposed to be hot [in the] summer time, but this is exceptional heat driven by climate change and that if this isn't the future that we want to continue, then we need to start curbing the pollution and figuring out ways to get back to a more suitable climate for us," Winkley said.