Advertisement

Supported by

Guest Essay

By Gavin Schmidt and Zeke Hausfather

Dr. Schmidt is a climate scientist in New York City. Dr. Hausfather is the climate research lead at Stripe and a research scientist at Berkeley Earth.

The earth has been exceptionally warm of late, with every month from June 2023 until this past September breaking records. It has been considerably hotter even than climate scientists expected. Average temperatures during the past 12 months have even been above the goal set by the Paris climate agreement: to keep global warming below 1.5 degrees Celsius over preindustrial levels.

We know human activities are largely responsible for the long-term temperature increases, as well as sea level rise, increases in extreme rainfall and other consequences of a rapidly changing climate. Yet the unusual jump in global temperatures starting in mid-2023 appears to be higher than our models predicted (even as they generally remain within the expected range).

Jan 2023

Jul

Jan 2024

Jul

0.8

1.2

1.4

1.6

1.8°C above preindustrial average

Average global temperature

In Sept. 2023, the observed temperature was 0.5°C higher than the previous monthly record

Record-breaking months

Projected temperature range

Source: NASA Goddard Institute for Space Studies

Note: The projected range is based on the long-term temperatures trends combined with a three-month lag from the ocean temperatures in the tropical Pacific

While there have been many partial hypotheses — new low-sulfur fuel standards for marine shipping, an unusual volcanic eruption in 2022, lower Chinese aerosol emissions and El Niño perhaps behaving differently than in the recent past — we remain far from a consensus explanation even more than a year after we first noticed the anomalies. And that makes us........

© The New York Times