New research challenges the idea put forward in the most recent
IPCC report that there has been a so called "slowdown" in surface
warming recently, saying temperature rise in the last decade and a
half may be nothing unusual after all.
The paper - which is an updated look at one the major
temperature data sets the IPCC uses - suggests the rate of surface
warming since 1997 is more than twice previously thought. But
scientists tell us when you look a bit closer at the new data and
the IPCC's numbers, the two aren't inconsistent.
IPCC on the "slowdown"
A big discussion
point surrounding the latest climate report from the
Intergovernmental Panel on Climate Change (IPCC) is how surface
temperatures - that's the air above the land and oceans - have been
rising relatively slowly over the past decade and a half.
The IPCC report put the rate of warming between 1998 and 2012
0.05 degrees Celsius per decade. That's quite a lot slower
than the average of 0.12 degrees per decade since 1951.
In the report, this is given as an example of how natural
climate variability can cause temperatures to rise faster or slower
than than the long term average from one decade to the next.
new paper, just published in the journal Quarterly Journal of
the Royal Meteorological Society, takes a fresh look at one of the
main datasets the IPCC uses, the Met Office's HadCrut4 temperature
The authors say correcting for well-known gaps in the dataset -
to do with how much of the globe it covers - brings the rate of
warming since 1997 up to 0.12 degrees Celsius. In other words,
right in line with the decadal average.