The globe is set to pass a symbolic yet significant climate threshold in 2015 while careening into a new era of supercharged global warming, new data released Monday shows.

This year, global average surface temperatures are likely to reach 1 degree Celsius, or 1.8 degrees Fahrenheit, above preindustrial temperatures for the first time, according to the UK Met Office.

This puts the world halfway to the internationally agreed warming target of 2 degrees Celsius, or 3.6 degrees Fahrenheit.

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Other data, also released Monday, shows that 2016 will be the first year in all of human history when the amount of carbon dioxide in the air meets or exceeds 400 parts per million for the entire year. As of 2014, that annual figure was 397.7 parts per million, which is an astonishing increase of 143% from the level in the air prior to the industrial revolution, according to the World Meteorological Organization (WMO).

One degree makes a big difference

Based on data from January to September, the data kept by the Met Office and the Climate Research Unit at the University of East Anglia shows that 2015 global average temperatures are 1.02 degrees Celsius above preindustrial levels. (For preindustrial levels, the Met Office uses the period from 1850 to 1900, since global records in 1750 don't exist.)

This year is widely expected to be the world's warmest year on record, in part because of the warming influence of a strong El Niño event in the Pacific Ocean, which is adding more warming on top of the long-term manmade trend from greenhouse gas emissions.

"This is the first time we're set to reach the 1 degree Celsius marker, and it's clear that it is human influence driving our modern climate into uncharted territory," Stephen Belcher, director of the Met Office Hadley Center, said in a release.

Peter Stott, who leads the Met Office's climate monitoring and attribution unit, said not every year from now on will meet or eclipse the 1-degree Celsius warming mark, because of natural variability in the climate system.

"As the world continues to warm in the coming decades, however, we will see more and more years passing the 1 degree marker — eventually it will become the norm," Stott said.

The Met Office is one of four agencies in the world that maintain official global temperature records. Another of these groups, the National Oceanic and Atmospheric Administration (NOAA) in the U.S., corroborated the UK report on Monday.

Following @metoffice, GISTEMP 2015 anomaly is predicted to also be above 1ºC wrt pre-industrial for 1st time: pic.twitter.com/tyf5ug5kFB — Gavin Schmidt (@ClimateOfGavin) November 9, 2015

In addition, Gavin Schmidt, the director of NASA's Goddard Institute for Space Studies in New York, said via Twitter that its data shows the breaking of the 1 degree Celsius threshold this year as well.

Temperature rise toward the 1 degree Celsius threshold, seen in UK Met Office data. Image: Met Office

According to Jessica Blunden, a climate scientist at NOAA's National Centers for Environmental Information, told Mashable in an email that so far this year, global average temperatures are running at 1.05 degrees Celsius above the 19th century average.

The global average temperatures last year, which were the warmest year on record, fell short of the 1-degree milestone, Blunden added.

In the fast lane to 2 degrees?

According to the Met Office, the world has already emitted around two-thirds of the carbon dioxide it can put into the atmosphere to have a likely chance (more than 66% chance) of limiting warming to below 2 degrees Celsius.

World leaders will meet in Paris in early December for a major U.N. Climate Summit aimed at crafting a new global climate treaty that would limit emissions of greenhouse gases, but even the U.N. itself says that the new agreement is likely to be insufficient on its own of ensuring that warming doesn't exceed 2 degrees Celsius.

Image: Mashable/Bob Al-Greene

Various climate scientists say that warming beyond that point would set into motion inexorable changes in global ice sheets, thereby inundating coastal cities and small island nations from rising seas, and lead to species extinction, more damaging extreme weather events and a range of other harmful impacts.

Many of these impacts are already occurring, leading some scientists to conclude that we've already exceeded critical climate thresholds.

Illustrating the scope of the challenge for diplomats in Paris, the WMO report shows that between 1990 and 2014, a period that featured more than 20 international meetings to tackle climate change, the global warming influence from long-lived greenhouse gases such as carbon dioxide increased by 36%.

Global average surface temperatures compared to 1880-1900 levels from NOAA's database. Circle in upper right shows data for the January to September 2015 period.

“Every year we report a new record in greenhouse gas concentrations,” said WMO Secretary-General Michel Jarraud in a statement.

“Every year we say that time is running out. We have to act now to slash greenhouse gas emissions if we are to have a chance to keep the increase in temperatures to manageable levels,” he said.

During 2015, carbon dioxide levels reached and in some cases eclipsed the symbolic milestone of 400 parts per million, and the WMO expects 2016 to be the first year to have globally averaged carbon dioxide levels exceed 400 parts per million.

Amount of CO2 in the atmosphere during the past 800,000 years. Image: Scripps Institution of Oceanography/Mashable

“We will soon be living with globally averaged CO2 levels above 400 parts per million as a permanent reality,” Jarraud added. “Carbon dioxide remains in the atmosphere for hundreds of years and in the ocean for even longer. Past, present and future emissions will have a cumulative impact on both global warming and ocean acidification. The laws of physics are non-negotiable."

For comparison, the amount of carbon dioxide in the atmosphere at the start of the industrialized revolution was just 287 parts per million, the WMO says.

In fact, data going back 800,000 years shows that the levels of greenhouse gases in the air today is unprecedented in all of human history.