GWPF | 24 Nov 2014

UK Researchers Find Little Ice Age Was Global

Antarctica’s ice paradox has yet another puzzling layer. Not only is the amount of sea ice increasing each year, but an underwater robot now shows the ice is also much thicker than was previously thought, a new study reports. The discovery adds to the ongoing mystery of Antarctica’s expanding sea ice.  According to climate models, the region’s sea ice should be shrinking each year because of global warming. Instead, satellite observations show the ice is expanding, and the continent’s sea ice has set new records for the past three winters. –Becky Oskin, LiveScience, 24 November 2014

A team of UK researchers has shed new light on the climate of the Little Ice Age, and rekindled debate over the role of the sun in climate change. The new study, which involved detailed scientific examination of a peat bog in southern South America, indicates that the most extreme climate episodes of the Little Ice Age were felt not just in Europe and North America, which is well known, but apparently globally. These extreme times coincide with periods when it is known that the sun was unusually quiet. In the late 17th to mid-18th centuries it had very few sunspots—fewer even than during the run of recent cold winters in Europe, which other UK scientists have linked to a relatively quiet sun. —University of Gloucestershire, 18 November 2014

Some media outlets have been reporting that the oceans are starting to get warmer, and that it signals the end to the current hiatus in annual average global surface temperatures. 2014 is going to be warm, but how warm, and the year’s rank depends upon which data you use. I suspect that if 2014 does technically become the warmest year on record (in any one of the non-satellite data sets) then we will see dramatic headlines to that effect, even if the record is broken by a hundredth or a few thousandths of a degree. The real story will be that the so-called biggest puzzle in climate science – the global surface temperature standstill – then entering its 19th year. –David Whitehouse, Global Warming Policy Forum, 22 November 2014

1) Antarctic Ice Thicker Than Previously Thought, Study Finds – LiveScience, 24 November 2014

2) UK Researchers Find Little Ice Age Was Global, With Implications For Current Global Warming – University of Gloucestershire, 18 November 2014

3) David Whitehouse: Warm Ocean, Warm Year? – Global Warming Policy Forum, 22 November 2014

1) Antarctic Ice Thicker Than Previously Thought, Study Finds
LiveScience, 24 November 2014

Becky Oskin

Antarctica’s ice paradox has yet another puzzling layer. Not only is the amount of sea ice increasing each year, but an underwater robot now shows the ice is also much thicker than was previously thought, a new study reports.

The discovery adds to the ongoing mystery of Antarctica’s expanding sea ice.

According to climate models, the region’s sea ice should be shrinking each year because of global warming. Instead, satellite observations show the ice is expanding, and the continent’s sea ice has set new records for the past three winters. At the same time, Antarctica’s ice sheet (the glacial ice on land) is melting and retreating.

Measuring sea ice thickness is a crucial step in understanding what’s driving the growth of sea ice, said study co-author Ted Maksym, an oceanographer at the Woods Hole Oceanographic Institution in Massachusetts. Climate scientists need to know if the sea ice expansion also includes underwater thickening.

“If we don’t know how much ice is there is, we can’t validate the models we use to understand the global climate,” Maksym told Live Science. “It looks like there are significant areas of thick ice that are probably not accounted for.”

The findings were published today (Nov. 24) in the journal Nature Geoscience.

Like icebergs, much of Antarctica’s floating sea ice is underwater, hidden from satellites that track seasonal sea ice. And it’s difficult to take direct measurements from ships or drilling, because the thickest ice is also the hardest to reach, Maksym said.

The researchers were stuck aboard an icebreaker in 20-foot-thick (6 meters) pack ice for more than a week after taking advantage of a lead, or open water, that accessed thick ice, he said. “Obviously that carried some risk, and we were stuck until the wind changed direction again,” he said.

Full story

2) UK Researchers Find Little Ice Age Was Global, With Implications For Current Global Warming
University of Gloucestershire, 18 November 2014

A team of UK researchers has shed new light on the climate of the Little Ice Age, and rekindled debate over the role of the sun in climate change. The new study, which involved detailed scientific examination of a peat bog in southern South America, indicates that the most extreme climate episodes of the Little Ice Age were felt not just in Europe and North America, which is well known, but apparently globally. The research has implications for current concerns over ‘Global Warming’.

Climate sceptics and believers of Global Warming have long argued about whether the Little Ice Age (from c. early 15th to 19th Centuries) was global, its causes, and how much influence the sun has had on global climate, both during the Little Ice Age and in recent decades. This new study helps clarify those debates.

The team of researchers, from the Universities of Gloucestershire, Aberdeen and Plymouth, conducted studies on past climate through detailed laboratory examination of peat from a bog near Ushuaia, Tierra del Fuego. They used exactly the same laboratory methods as have been developed for peat bogs in Europe. Two principal techniques were used to reconstruct past climates over the past 3000 years: at close intervals throughout a vertical column of peat, the researchers investigated the degree of peat decomposition, which is directly related to climate, and also examined the peat matrix to reveal the changing amounts of different plants that previously grew on the bog.

The data show that the most extreme cold phases of the Little Ice Age—in the mid-15th and then again in the early 18th centuries—were synchronous in Europe and South America. There is one stark difference: while in continental north-west Europe, bogs became wetter, in Tierra del Fuego, the bog became drier—in both cases probably a result of a dramatic equator-ward shift of moisture-bearing winds.

These extreme times coincide with periods when it is known that the sun was unusually quiet. In the late 17th to mid-18th centuries it had very few sunspots—fewer even than during the run of recent cold winters in Europe, which other UK scientists have linked to a relatively quiet sun.

Professor Frank Chambers, Head of the University of Gloucestershire’s Centre for Environmental Change and Quaternary Research, who led the writing of the Fast-Track Research Report, said:

“Both sceptics and adherents of Global Warming might draw succour from this work. Our study is significant because, while there are various different estimates for the start and end of the Little Ice Age in different regions of the world, our data show that the most extreme phases occurred at the same time in both the Northern and Southern Hemispheres. These extreme episodes were abrupt global events. They were probably related to sudden, equator-ward shifts of the Westerlies in the Southern Hemisphere, and the Atlantic depression tracks in the Northern Hemisphere. The same shifts seem to have happened abruptly before, such as c. 2800 years ago, when the same synchronous but opposite response is shown in bogs in Northwest Europe compared with southern South America.

“It seems that the sun’s quiescence was responsible for the most extreme phases of the Little Ice Age, implying that solar variability sometimes plays a significant role in climate change. A change in solar activity may also, for example, have contributed to the post Little Ice Age rise in global temperatures in the first half of the 20th Century. However, solar variability alone cannot explain the post-1970 global temperature trends, especially the global temperature rise in the last three decades of the 20th Century, which has been attributed by the Inter-Governmental Panel on Climate Change (IPCC) to increased concentrations of greenhouse gases in the atmosphere.”

Professor Chambers concluded: “I must stress that our research findings are only interpretable for the period from 3000 years ago to the end of the Little Ice Age. That is the period upon which our research is focused. However, in light of our substantiation of the effects of ‘grand solar minima’ upon past global climates, it could be speculated that the current pausing of ‘Global Warming’, which is frequently referenced by those sceptical of climate projections by the IPCC, might relate at least in part to a countervailing effect of reduced solar activity, as shown in the recent sunspot cycle.”

3) David Whitehouse: Warm Ocean, Warm Year?
Global Warming Policy Forum, 22 November 2014

Some media outlets have been reporting that the oceans are starting to get warmer, and that it signals the end to the current hiatus in annual average global surface temperatures.

Mother Nature Network says the pace of ocean warming is speeding up. “Earth’s ocean surface has been hotter in 2014 than any previous year on record, according to a new analysis by scientists at the University of Hawaii-Manoa. This suggests the recent slowdown in Earth’s long-term temperature rise — sometimes called a “hiatus” — may be coming to an ominous end.”

Responding to Climate Change includes the quote,  “Hottest ever ocean temperatures signal end to warming pause.” It also adds: But as to whether the global warming pause was over in terms of atmospheric temperatures, Met Office climate scientist Richard Betts said it was too early to say. “Even if this year ends up with a record global average surface temperatures, which is possible, that would just be one year. We’d need more than that,” he told RTCC. Betts added: “‘Has the pause ended?’ will be an important research question for some years.”

The origin of these reports was a statement made by Axel Timmermann of the University of Hawaii that temperatures in the Pacific are even greater than that during the 1998 El Nino. Timmermann suggests that this is the end of the 14-year pause in ocean surface warming. He says in April 2014 it picked up again.

A closer look at the data, Fig 1, shows that the unusual warm is confined to the North Pacific. This suggests local effects like changing wind strengths pooling warm surface water in one particular location, a quite different effect from global warming.

Fig 1. Click on image to enlarge.

Timmerman says a shift in summer trade winds played a key role, allowing nearly a decade’s worth of stored heat to escape from the tropical Western Pacific. “Record-breaking greenhouse gas concentrations and anomalously weak North Pacific summer trade winds, which usually cool the ocean surface, have contributed further to the rise in sea surface temperatures,” Timmerman says. “The warm temperatures now extend in a wide swath from just north of Papua New Guinea to the Gulf of Alaska.”

So this effect is short-term and localised, something some of the media reports missed.

Also note the overall ocean warming started in 1910 which is curiously at the same time that sea level rise changed its gradient due to unknown factors which certainly do not include any anthropogenic influence, see Fig 1a.

Fig 1a. Click on image to enlarge.

The story did not get widespread coverage. Unlike the prospect of 2014 being the warmest year in the instrumental temperature record.

Is 2014 on track to be the warmest year?

It is going to be warm, but how warm, and the year’s rank depends upon which data you use.

According to the National Climatic Data Center (NCDC) the ocean surface temperature for October 2014 was globally the highest on record with a temperature anomaly of 0.62 deg C. Despite the land temperature for October being the 5th warmest the land-ocean temperature was the highest on record at 0.74 deg C.

So let’s look at year to October sea surface temperatures in their database, Fig 2. You will see that it is nothing particularly special. We are dealing with statistically insignificant variations of 0.05 deg C inside an error of at least 0.1 deg C. The trend for January-October between 2001-2014 is 0.01 deg C per decade with an error of 0.15 deg C per decade, i.e. there is no trend.

Fig 2. Click on image to enlarge.

The NCDC has a year-to-date graph, Fig 3, (such a representation of this data set was first used by the GWPF) showing that only in September was 2014 warmer than 2010.

Fig 3. Click on image to enlarge.

They also produce a prediction for the remaining two months, Fig 4, suggesting that 2014 will probably be the warmest year on record, probably by 0.01 or 0.02 deg C which is of course statistically insignificant. Why does the NCDC not put error bars on these graphs – most unscientific.

Fig 4. Click on image to enlarge.

The “warmest year on record” story will, by the years end, certainly sort out responsible journalists and commentators from those who just seek headlines. Expect to see a lot of headlines mentioning the warmest ever year and rather few of the surface temperature hiatus continues, which is the only conclusion that can be drawn from the data.

But will 2014 be the warmest year in other databases?

Consider Nasa Giss which essentially uses the same data as the NCDC but processes it in a different way. In Giss the year to October has an average temperature anomaly of 66 which is the same as that of 2005 and 2010. November and December 2014 must have an average of 67 to make 2014 the warmest year by just a statistically insignificant 0.01 degrees.

Since 2001 only one year, 2006, has had November and December both above 66. Of all the Novembers and Decembers since 2001 only 10 out of 26 have had temperature anomalies above 66, and the last December to achieve this was in 2006 and only twice since 2001. Because about half of Novembers since 2001 have had a temperature anomaly above 66 it is likely that the status of warmest ever year in Giss will not be decided by December not being exceptionally warm but by not being exceptionally cold. Thus at the end of the year Giss data will confirm that the global surface temperature hiatus continues.

Note that in Giss October ties for the warmest month with 2005, although this is really grubbing around in the noise for meaningless comparisons.

HadCrut4 is showing 2014 as a record year but only by 0.004 deg C which is superfluous. This will change with the inclusion of data from October, November and December. By year’s end HadCrut4 will also confirm that the temperature hiatus continues.

Satellite data tell a different story. RSS global data show that 2014 will be cooler than 2010, 2007, 2005, 2003, 2002 and 1998 (2014 will be over 0.02 deg cooler than 2010). By year’s end 2014 will probably be about the sixth warmest year.

UAH data shows that currently 2014 ranks 3rd and is likely to remain so by year’s end. There is no chance whatsoever that the satellite datasets will show 2014 to be a record year.

I suspect that if 2014 does technically become the warmest year on record (in any one of the non-satellite data sets) then we will see dramatic headlines to that effect, even if the record is broken by a hundredth or a few thousandths of a degree. The real story will be that the so-called biggest puzzle in climate science – the global surface temperature standstill – then entering its 19th year.