"Overnight lows are a big concern, warm overnight lows that just don't let your body cool off are more directly correlated with heat-related mortality,” said Lauren Casey, meteorologist of Climate Central.“It uses a lot of statistical methods so basically like very fancy science to determine if and to what extent human-caused climate changes altered the likelihood of daily temperatures,” said Casey.
The scale runs from negative five, meaning less likely an impact, to positive five, which is more likely an impact, or zero which means no impact from climate change. The concern for Phoenix this summer was the consistent CSI score of positive 3 and 4 during our overnight for several months. “When the numbers go in the positive direction because a CSI of 3 means that climate change made those temperatures. Now take that same air mass and put it 50 or 60 years ago that temperatures wouldn't be as warm as what you are experiencing today because of the influence of human-driven climate change,” said Casey.
Heat-related illnesses, decreased air quality and an increase in energy bills are all affected by this. “This warming trend is only going to continue unless we curb our reliance on fossil fuels, we need to bend back that trend,” said Casey.“We need to expand early warning systems and heat action plans we need to invest in long-term adaptation measures to deal with the heat and warming we have already been experiencing and plan for more warming in the future,” said Casey.