So Los Angeles residents have done a good job on their way to meeting California Governor Jerry Brown’s 20 percent water reduction mandate by next year.

There’s one small problem, point out University of Southern California researchers in the Los Angeles Times. These drought-friendly plants and turf alternatives might be making the city hotter.

As we all know, turf and trees help provide shade from the sun and give off moisture to cool the air. The USC report reveals that if the city had no lawns, it would be 3.4 degrees hotter at mid-day. This could add to climate change-related temperature hikes.

The positive news from this study is that the nighttime cooling effect of gravel and low-water vegetation is so strong because they reflect more cool air at night than turf, that it might cancel out the overall environmental warming.

But since most people are active and outside during daylight hours, this doesn’t help the city’s initiative encouraging commuters to bike and walk instead of drive to battle climate change.