Granite Geek: Weather extremes are here to stay and are just going to get more extreme
|Published: 09-06-2023 4:00 PM
It’s not really accurate to say that we’re seeing a “new normal” in the current hot spell – Tuesday’s high of 92 degrees was a record for Sept. 5 in Concord – because when you’re talking about weather it’s getting harder and harder to say what’s normal.
“Our new normal is all over the place,” said Mary Stampone, a UNH professor who is the state climatologist. “That’s what climate change does. You’re adding energy into the system. That energy is bumping up the hottest temperatures but also putting more energy into the weather systems. We’re seeing a lot more variability: heavier rain, more intense drought, and lots of ups and down in between.”
Globally, the three months of June through August were the hottest on record – a full degree Fahrenheit above the long-term average, a huge variation for the planet as a whole – but New Hampshire mostly dodged that bullet. July was quite hot here but no record and August was cooler than average, which makes it harder to adjust to the current hot spell. (We’re not yet in an official heat wave, defined as three days in a row above 90 degrees, although we may hit that by Thursday.)
We’ve also been wet, as farmers can attest. Although total precipitation is not a record it has been high: July and August saw 10.15 inches of rain in Concord, a full 45% above the long-term average. That’s why we have not seen the wildfire problem that has scorched Canada and parts of the American West. The state has rated our wildfire risk as “low” all summer long, which is unusual.
Such variability is an increasing factor in the climate-changed world, Stampone noted. Extremes are becoming more extreme and for obvious reasons.
“What we’re seeing with heat, especially in other regions, that is way outside of normal ranges. If you see it in terms of the bell curve, these are such an outlier that normal weather fluctuations don’t explain it,” Stampone said. “It’s climate change. It’s alarming.”
So while this week’s heat may not be a record for Concord, it is a reminder.
“We need to remind ourselves there is still time to avoid the worst impacts. We’re seeing it now but if we don’t mitigate greenhouse gases, it’s going to get worse,” said Stampone.]]>