Despite scorching July, 1.5C Paris climate limit not yet reached

Despite scorching July, 1.5C Paris climate limit not yet reached
By Julien Mivielle
Paris (AFP) Aug 10, 2023

The average global temperature in July, the hottest month in recorded history, was around 1.5 degrees Celsius warmer than in pre-industrial times.

The Paris Agreement set the ambitious target of limiting the world to a temperature increase of 1.5C, but last month's blistering heat does not mean this threshold has been breached -- the deal instead refers to change that takes place over decades.

- 1.5C occasionally exceeded -

The month of July was "estimated to have been around 1.5C warmer than the average for 1850-1900," the European Union's Copernicus Climate Change Service said on Tuesday.

It also confirmed that July was the hottest on record for any month.

But it is not the first time that the 1.5C threshold has been temporarily reached -- or even exceeded.

In December 2015, just as nations were convening in the French capital to negotiate the landmark Paris Agreement, the world experienced average global temperatures above 1.5C pre-industrial levels as the Pacific Ocean warming phenomenon El Nino neared its peak.

The limit was also reached or passed in the winter or early spring of 2016, 2020, and earlier this year.

With the first El Nino in four years just warming up, more records could fall in the coming years.

- Lower limit of Paris deal -

The Paris Agreement was signed in 2015 with the goal of holding the "the increase in the global average temperature to well below 2C above pre-industrial levels" and to pursue efforts "to limit the temperature increase to 1.5C above pre-industrial levels".

But just one hot month does not mean that the lower threshold has been breached.

"It must be stressed that the 1.5C and 2C limits set in the Paris Agreement are targets for the average temperature of the planet over the 20 or 30-year periods typically used to define climate," Copernicus said in a statement in June.

The World Meteorological Organization estimates there is a 66 percent chance that the annual average global temperature will temporarily exceed pre-industrial levels by more than 1.5C for at least a year between 2023-2027.

"This is not to say that in the next five years we would exceed the 1.5C level specified in the Paris Agreement because that agreement refers to long-term warming over many years," the WMO's director of climate services Chris Hewitt said in July.

"However, it is yet another wake-up call, or an early warning" he added.

- A 30-year average -

The Paris Agreement does not provide a precise definition for the temperatures it refers to, unlike the specific years given for the pre-industrial benchmark, but scientists have attempted to clear up any ambiguity.

In a 2018 IPCC special report, climate experts urged the world to aim for the lower limit rather than 2C to avoid major climate impacts, such as heatwaves, super hurricanes and destabilised ice caps.

They defined warming as "the increase in the 30-year global average" expressed relative to "the reference period 1850-1900."

"The 30-year timespan accounts for the effect of natural variability, which can cause global temperatures to fluctuate from one year to the next," the IPCC said.

In defining the pre-industrial timeframe, which refers to the period before the climate was altered by fossil fuels emitted by human activities, the scientists chose 1850-1900 because it was "the earliest period with near-global observations," it added.