The length of the “pause”, “hiatus”, slowdown”, or “plateau”, whatever you wish to call it, is of great interest to sceptics and mainstream climate scientists alike, although Global Warming Enthusiasts such as John Cook try to pretend it doesn’t exist and/or is not important.
In this post I am showing the length of time during which the linear trend of temperatures is less than +0.01C per 100 years- i.e. zero or negative. I use the UAH version 6 data to April 2015 which has been recently released, for various regions of the globe. University of Alabama (Huntsville) data are derived from satellite radiosonde data for the lower troposphere. These represent how the bulk of the atmosphere is behaving.
I am well aware of the criticism that commencing the trend calculation near the 1997-1998 El Nino may distort the trend, so these calculations merely show how far in the past we can go to find a zero or negative trend. (In a future post I intend to exclude the big lump of data around this period for an alternative look at trends.) In several of these plots there is very little discernible bulge around 1997-1998 at all, so I consider the trends are valid.
Firstly, how long is the pause globally?
Fig. 1: Global data with zero trend (less than +0.01C/100 years) (Click to enlarge)
This includes the 1997-98 El Nino which may distort the trend calculation. However, see several plots below which don’t show this effect.
Fig. 2: North Polar (60 degrees North to 90 degrees North)
Despite claims to the contrary, during this admittedly short period the Arctic has not been warming.
Fig. 3: Northern Hemisphere (Equator to 90 Degrees North)
Only slightly shorter than for the whole globe. Trend= +0.007C/100 years.
Fig. 4: Southern Hemisphere (Equator to 90 degrees South)
This includes three years before the 1997-98 El Nino. The trend is +0.006C/100 years.
Fig. 5: Tropics (20 degrees North to 20 degrees South)
The tropics include the Tropical Pacific where ENSO events are identified, and the pause extends well before the super El Nino.
Now you’ve heard that Antarctic sea ice is expanding to new records, but of course this is due to, variously, stronger katabatic winds and/or melt water filling the gaps and freezing over- all due to global warming naturally. But you may have a suspicion that the Antarctic region is not actually warming as much as global warming enthusiasts would have you believe. Has there been a pause in Antarctica?
Fig. 6: South Polar region (below 60 degrees South)
Now that’s a Pause!
I also checked pause length for Australia and the USA.
Fig. 7: Australia
There does not appear to be an unusually large spike during 1997-98.
What about our North American cousins?
Fig. 8: Contiguous USA
The effects of the 1997-98 El Nino do not have a large influence here either.
Note to Global Warming Enthusiasts: The Pause is real! Build a bridge and get over it!