Scientists say heat waves are becoming more common, and this June set major records.
The National Centers for Environmental Information said there have been 13 consecutive months of record-warm temperatures around the world. The organization said temperatures were above average for much of the world.
Sea surface temperatures also hit record-warm levels for the 15th consecutive month.
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June's global surface temperature was 1.89 degrees above the 20th-century average of 59.9 degrees Fahrenheit, making it the warmest June on record, NOAA reported.
The Cleveland Clinic said research shows heat can create cognitive issues and problems with mental health.
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The body produces the stress hormone cortisol to cope with the stress excessive heat puts on the body, which can lead to anxiety and stress. It's unclear if extreme heat can be the cause of mental health issues, but it can exacerbate already existing mental health problems, experts say.
The best thing to do during hot months is to find ways to cool back down, research shows.