Summer of 2023 was the hottest in two millennia, says study

A new study analyzing ancient tree rings reveals that last summer was the hottest in the past 2,000 years, with unprecedented warmth across the Northern Hemisphere.

Doyle Rice reports for USA Today.

In short:

• Tree rings indicate summer 2023 was 4 degrees warmer than the average from 1 to 1890.
• The study suggests that current warming trends surpass the goals of the 2015 Paris Agreement.
• High heat fueled severe weather events globally, from wildfires to intense heat waves and heavy rains.

Key quote:

“It’s true that the climate is always changing, but when you look at the long sweep of history, you can see just how dramatic recent global warming is.”

— Jan Esper, lead author, Johannes Gutenberg University

Why this matters:

Such unprecedented heat is a stark reminder of the urgent need to reduce greenhouse gas emissions to mitigate severe health impacts and prevent further climate-related disasters. Read more: Heat, air pollution and climate change … oh my! Was summer 2023 the new normal?