Antarctic Temperature Trends
By Paul Homewood
David correctly points out that RSS satellite temperatures only cover as far south as 70S, whereas UAH go to 85S. This could explain part of the difference between the two datasets.
So, it is worth looking at what the trends have been in Antarctica, using UAH figures.
http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc_lt_5.6.txt
As can be seen, there were two major cooling episodes, centred around 1993/94 and 1999/2000, since which temperatures have recovered back to the levels of the 1980’s. Indeed the 120-Month running average is still not as high as it was in 1990.
This long term average has also been stable since 2011, implying that there has been little change since 2001.
Meanwhile, down at the pole itself, nothing much seems to be happening either, according to GISS.
http://data.giss.nasa.gov/cgi-bin/gistemp/show_station.cgi?id=700890090000&dt=1&ds=12
Finally, let’s check out the SST’s for the Southern Ocean, from Bob Tisdale’s website.
http://bobtisdale.wordpress.com/2014/05/05/april-2014-sea-surface-temperature-sst-anomaly-update/
All the evidence points in the same direction – there has been no warming in or around Antarctica since 1979. On the contrary, if there is any trend, it is to a cooler climate.
Trackbacks
- Antarctica: No Warming Since 1979 | The Global Warming Policy Foundation (GWPF)
- Weekly Climate and Energy News Roundup | Watts Up With That?
Comments are closed.
NOT A LOT OF PEOPLE KNOW THAT 
Hi Paul
Many thanks for your as always interesting info.
The oceans rule our climate, the SH has four times more ocean than land, so you provide good advice to keep a weather eye on the southern oceans:-
Question from a confused layman; very roughly, it seems 16 cubic kilometres of sea water at 3C is required to convert 1 cubic kilometre of ice to water at 0.01C. The result is about 17 cubic kilometres of cold slightly less salty water. The density ensures this water will remain at the surface for a while. Now, if Southern Ocean SST is decreasing, would this not indicate an INCREASE in the volume of ice melt?
If everything else was stable, that would be a possible explanation. To determine if that is the case or not one would have to know the increase/loss of total ice mass, the direction, size and impact of currents, amount of upwelling of colder ocean bottom waters, force and direction of wind currents, multi-year trend of cloud cover and also (I am assuming) some indication of strength and consistency of solar radiation. A lot of variables. A plot of annual temperatures is a crude device. It indicates direction, but not cause. Same could be said of land temperatures of course, except that land temperatures are confused by the preponderance of temperature measuring stations in North America and Europe, and the obvious impact of the urban heat island effect.
Thanks for the response Paul. Nothing is ever simple. (sigh) But I keep trying :-), How about one good thermometer in a large desert. A record of the night time MINIMUMS over a few decades should indicate if the world is warming or cooling.
That is an interesting idea.
Pick a location that is more or less stable and free of immediate human influences. A land form with low atmospheric moisture content, so all you are measuring is residual land temperature after giving up the maximum heat content during the night hours and thereby avoiding concurrent solar heating. And track trends from more or less latitudinaly comparable locations around the globe, in both the northern and southern hemispheres.
I understand the southern hemisphere is problematical, but if you used Australia, South Africa and Argentina in the south and central China, Algeria and the American south-west in the north, you might be able to claim analogous conditions. Forty years of night time minimums might be interesting to see. Forty years might avoid what seem to be 30 year cycles in temperature swings.
In 2012 I asked for comments fro RSS on the difference in coverage between RSS and UAH at the South Pole and received the following reply:
“For TLT, over the south pole, we concluded that too much (as much as 30-40%)
of the signal comes from the surface, not the atmosphere. Much of the ice sheet is
above 3000 meters, so there is not enough atmosphere left to get a good
measurement for TLT. Or, if you look at the figure on the website for the weighting function
for TLT, imagine the the surface sitting 3000 meters high in that diagram.
For TMT, which peaks high in the atmosphere, much more of
the signal comes from the atmosphere for regions where the surface of the
earth is at high altitude.
UAH covers everywhere, though the information right at the poles is extrapolated
because the satellites never measure there.”
Of course GISS, HC4 and NOAA all have their own methods, which I think go a long way to explaining differences in the Monthly SH and Global temperature anomalies.
@Paul Stevens. I had a three year contract in the Namib Desert some forty years ago. Not having much to do I tried learning astronomy. It was a big surprise finding out how cold it got in the early hours of a clear night. No big problem. Just dig a shallow trench in the sand and lie down. Lot of warmth in the sand about six inches down. (always check for little biters first!) Also hearing the surface of nearby rocks cracking off as the outer skin shrunk in the cold was fascinating back then. I’d love to go back and do some measurements. Anyway, I’ve never been able to believe in ‘back radiation’ and AGW because of my experiences in the desert. Are you aware the Romans used to make ice in the deserts 2000 years ago?
I expect ice in the desert would be definite proof of “Climate Change” :-). Fascinating. Did they use evaporative cooling? Hardly seems like you could get that much energy out using simple evaporation.
According to the following recent paper in Nature the last glaciation in West Antarctica may have been ended by a decrease in sea ice following an increase in insolation (no involvement of CO2!). With sea ice now increasing could we be heading for another ice age?
http://www.nature.com/nature/journal/v500/n7463/full/nature12376.html
Plenty of scientists are saying we are possibly on the brink of a significant cooling phase of this particular inter-glacial.
In the recent series “Britain’s Most Extreme Weather”, Alex Beresford said that the next ice age was due but that it might be delayed/reduced by “global warming”.
I would have thought that would be a “good thing”!
This layman has been unable to find any ‘science’ explaining how ‘global warming’ actually works. I can use science to explain how ‘green house gasses’ cool the atmosphere. I think the real indicator of an approaching ‘ice age’ is the rate of winter snow melt in the Northern Hemisphere. The longer the snow lasts the shorter the food growing period and the cooler the summers.
Interesting, considering we have just been through the warm phase of the PDO.
Reflection from excess sea ice will cause positive feedback resulting in Snowball Earth by the end of the decade. It’s obvious.
I think its more complicated than that. Ice is a very good heat insulator, so more ice may mean less heat loss. Polar regions have net heat loss, net gain near the Equator.
Well it’s just turned 2017 and UAH now show a slight warming for Antarctica (the continent). Their latest version of the lower trop data handily has the decadal trends at the bottom of the data table. SoPol Land has a slight warming trend of 0.07C/decade.
http://www.nsstc.uah.edu/data/msu/v6.0/tlt/uahncdc_lt_6.0.txt