This is what happens when a team of scientists looks at the world’s heat records over the past few years and comes up with some startling insights.
In their paper published in Nature Climate Change, researchers from Australia, China, Finland, India, Italy, Norway, South Africa and the United Kingdom look at temperature data from all over the world, and then compare them to records from the past five decades.
They found that the average global temperature over the last five decades has risen by 0.5C.
This, they argue, means that “the observed warming of the past 10 years is statistically indistinguishable from a warming of 0.7C”.
In other words, they found no clear evidence of a warming trend in the recent past, and they didn’t find any clear evidence that global temperatures have been on the rise since 2007.
This is a big deal.
If you look at what we see in the data, it’s very, very clear that we’re on track for a warming that is, on average, 0.3C, or 0.4F, or slightly higher than that.
And this is what we are talking about when we talk about “climate change”.
We’re not just seeing the effects of global warming, we’re seeing the full impact of it, says lead author Professor Alan Robock, from the University of Sydney’s School of Earth Sciences.
“We’re seeing a massive amount of warming, not just in the global climate system, but in the whole of the atmosphere,” he says.
So, if the world really is on track to reach a 0.9C temperature rise by 2100, then we’ve got a big problem on our hands, he says, adding that it would be “unfair to say that the world is on the brink of a new ice age”.
The paper also looks at temperature trends from different parts of the world over the next 10 years, which is also an indication that there are some important changes in the climate system that are still happening, the scientists write.
“The trend in global temperature during the last 5 years, for example, is 0.2C above the 1981–2010 average,” they say.
But the paper also looked at different parts in the world.
For example, in the US, temperatures were already above the 1951–1980 average in December.
So the paper is clear that “global warming is not slowing down”.
And there are other important results as well, they say, including “that, if all of the observed warming since 2007 is statistically similar to a cooling trend of 0,7C, the observed global warming since the late 20th century is statistically significant, and is not expected to decrease”.
Professor Robock says the paper provides “the clearest evidence of the potential impact of climate change on the global temperature record”.
“It’s really clear that the temperature is changing, and it’s going to continue to change, and if we don’t act now, we’ll see some serious consequences in the future,” he said.
The article is reproduced with permission and was first published on November 15, 2017.