Posts Tagged ‘Little Ice Age’

The Little Ice Age was real and it was global

November 22, 2014

Global warmists like to pretend sometimes that the Little Ice Age and the Medieval Warm Period were not real or that they were just some local phenomena. The usually point to the lack of data from the southern hemisphere to support their claims. They certainly don’t like to admit that global cooling or warming events could have been caused by solar effects which were perhaps connected to the level of solar activity (as indicated by sunspots). New work at the University of Gloucestershire shows that not only was the Little Ice Age real but that it was present in both hemispheres. And that it was probably due to solar effects

AlphaGalileo reports:

UK researchers show Little Ice Age was global, wit.h implications for current Global Warming

Under embargo until 20 November 2014 00:01 GMT

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.”

Signs of global cooling accumulate while IPCC denies evidence and relies on models

November 2, 2014

Rational argument cannot penetrate faith.

Ask for evidence and you get model results. Ask for proof that the models are valid and you get hindcasts based on adjusted data. Ask for evidence of man-made emissions causing global warming and the answer is that it must be so for there is no other explanation. There isn’t if you don’t want to see it.

The IPCC believes that model results – even where the models are wrong – provide “conclusive” evidence of not just man-made global warming but that it is due to the emissions of carbon dioxide. It is politics not science. And the politics from India and China have ensured that the IPCC accepts fossil fuels till 2100!!!

For there is – in fact – no actual evidence in the form of data or measurements. There are only model results. There are only model forecasts where the track record shows that every IPCC forecast has been wrong. Fossil fuels – especially gas – will be around and will continue for many hundreds of years unless cheap fusion comes earlier.

Instead of real data showing support for the models, the evidence is accumulating that not only are the models wrong, but also that there are more indications that a global cooling is underway rather than global warming. Real measurements and real data show:

  1. that global temperatures have been stagnant for 18 years while carbon dioxide emissions have increased by 70% and carbon dioxide concentration has increased just under 15%,
  2. that therefore carbon dioxide concentration in the atmosphere has had no significant effect on global temperature,
  3. that the emissions and absorption of carbon dioxide from “natural” causes has an uncertainty of around 10%
  4. that man made carbon dioxide emissions make up less than 5% of all carbon dioxide emissions and their contribution to carbon dioxide concentration is of the order of 40% (assuming that there is no lag between accumulation of carbon dioxide in the atmosphere and absorption mechanisms from the atmosphere),
  5. that global temperatures actually show a small downward trend over the last 10 years,
  6. that global temperatures of the past have been corrupted by being adjusted or otherwise homogenised with the intent (conscious or unconscious) to cool the past,
  7. that man-made carbon dioxide emissions have been overestimated and in reality are much lower as a proportion of natural emission sources,
  8. that natural carbon dioxide absorption processes are larger than assumed,
  9. that Antarctic ice cover is at the highest levels ever recorded,
  10. that Arctic ice cover has returned to be within 1 SD of the long term 1980-2010 average,
  11. that the rate of sea-level rise is still at the same rate as the long-term recovery from the last glacial,
  12. that snow cover in the northern hemisphere is increasing
  13. that ice cover on the Great Lakes is increasing,
  14. that there is more forest cover now than when the alarmism began, and
  15. that polar bear numbers are healthy and increasing,

Add to this that a VEI5+ volcano eruption has not occurred since 1991 and is long overdue. It will most likely show up along the Pacific Ring of Fire or in Indonesia. Consider also that the Bárðarbunga  volcano in Iceland has been producing sulphur dioxide at a rate which in 9 weeks has pumped twice as much SO2 into the atmosphere than all of Europe does in a year. Bárðarbunga  volcano is far from VEI5+ levels and the eruption could continue for months. The SO2 emissions are not all reaching the stratosphere but will surely lead to increased cloud formation around sulphur aerosols and cloud levels will probably be high through at least next year. It becomes increasingly clear that further cooling effects are already in the “natural” pipeline of events. Some new glacier formation has been observed in the Scottish highlands. Some Alpine and Himalayan glaciers have started to increase and while others still decrease, the observation of increase where there has been none before is highly significant. The Great lakes have seen unprecedentedly high ice cover levels. Snow cover in the northern hemisphere is high and is lasting longer into spring than for some time.

But the models and the presuppositions and the misconceptions of the religious high priests cannot be easily denied by the faithful and have an inertia of their own. The IPCC  remains delusional and in denial about reality. It continues to play its global warming fiddle but it is badly out of tune and its alarmist cacophony is being overtaken by real events.

It may not be a glacial age that is starting but another Little Ice Age looks like it is on its way.

Little Ice Age was due to low solar irradiance

March 10, 2014

The Sun is the only real source of energy available at the surface of the earth (and any heat from nuclear reactions at the earth’s core is extremely small if not completely negligible). That the oceans have a much higher heat capacity than the atmosphere at the surface of the earth is obvious. It seems also fairly clear to me that it is the dynamics of ocean – atmosphere interactions which control climate and weather. And it is the oceans and long time scales which dominate climate while it is the atmospheric variations and short time scales which determine weather.

But the driver is always the Sun.

A new paper in Nature GeoScience “used seafloor sediments taken from south of Iceland to study changes in the warm surface ocean current. This was done by analysing the chemical composition of fossilised microorganisms that had once lived in the surface of the ocean. These measurements were then used to reconstruct the seawater temperature and the salinity of this key ocean current over the past 1000 years.”

The researchers found that ” low solar irradiance promotes the development of frequent and persistent atmospheric blocking events, in which a quasi-stationary high-pressure system in the eastern North Atlantic modifies the flow of the westerly winds. We conclude that this process could have contributed to the consecutive cold winters documented in Europe during the Little Ice Age.”

Paola Moffa-Sánchez, Andreas Born, Ian R. Hall, David J. R. Thornalley, Stephen Barker. Solar forcing of North Atlantic surface temperature and salinity over the past millenniumNature Geoscience, 2014; DOI: 10.1038/ngeo2094

AbstractThere were several centennial-scale fluctuations in the climate and oceanography of the North Atlantic region over the past 1,000 years, including a period of relative cooling from about AD 1450 to 1850 known as the Little Ice Age. These variations may be linked to changes in solar irradiance, amplified through feedbacks including the Atlantic meridional overturning circulation. Changes in the return limb of the Atlantic meridional overturning circulation are reflected in water properties at the base of the mixed layer south of Iceland. Here we reconstruct thermocline temperature and salinity in this region from AD 818 to 1780 using paired δ18O and Mg/Ca ratio measurements of foraminifer shells from a subdecadally resolved marine sediment core. The reconstructed centennial-scale variations in hydrography correlate with variability in total solar irradiance. We find a similar correlation in a simulation of climate over the past 1,000 years. We infer that the hydrographic changes probably reflect variability in the strength of the subpolar gyre associated with changes in atmospheric circulation. Specifically, in the simulation, low solar irradiance promotes the development of frequent and persistent atmospheric blocking events, in which a quasi-stationary high-pressure system in the eastern North Atlantic modifies the flow of the westerly winds. We conclude that this process could have contributed to the consecutive cold winters documented in Europe during the Little Ice Age.

Cardiff University Press Release:

Changes in the sun’s energy output may have led to marked natural climate change in Europe over the last 1000 years, according to researchers at Cardiff University. The study found that changes in the Sun’s activity can have a considerable impact on the ocean-atmospheric dynamics in the North Atlantic, with potential effects on regional climate.

Scientists studied seafloor sediments to determine how the temperature of the North Atlantic and its localised atmospheric circulation had altered. Warm surface waters flowing across the North Atlantic, an extension of the Gulf Stream, and warm westerly winds are responsible for the relatively mild climate of Europe, especially in winter. Slight changes in the transport of heat associated with these systems can lead to regional climate variability, and the study findings matched historic accounts of climate change, including the notoriously severe winters of the 16th and 18th centuries which pre-date global industrialisation.

The study found that changes in the Sun’s activity can have a considerable impact on the ocean-atmospheric dynamics in the North Atlantic, with potential effects on regional climate.

Predictions suggest a prolonged period of low sun activity over the next few decades ……..

Though their study has nothing whatever to do with global warming and any man-made effects they still feel it necessary to add this caveat (presumably because the reviewers, and the Journal, or both, insisted).

Predictions suggest a prolonged period of low sun activity over the next few decades, but any associated natural temperature changes will be much smaller than those created by human carbon dioxide emissions, say researchers.

The sun dances to its own tune with unexpectedly high activity in February

March 4, 2014

There is more we don’t know that we don’t know that we don’t know. (with apologies to Donald Rumsfeld).

While Solar Cycle 24 is still showing the lowest sunspot activity in 100 years, its activity during February was unexpectedly high.  And we don’t really know why.

SC24 Feb 2014 graphic NOAA data from informthpundits

SC24 Feb 2014 graphic NOAA data from informthepundits

The increased activity in February was certainly not expected but SC24 still remains at a very low activity level compared to recent Solar Cycles.

SC21 - SC24 from solen.info

SC21 – SC24 from solen.info

It is a little too early to see if the similarities with Solar Cycles 5 and 6 (during the time of the Dalton Minimum) will hold up and lead us into another Little Ice Age. Or whether this Landscheidt Minimum will just lead to a 30 year cooling period without quite producing a Little Ice Age.

Interesting times.

The Sun will continue to dance to its own tune and we will make believe that we know what it is doing.

But we ignore the Sun at our peril.

China to industrialise desalination of sea-ice

January 16, 2014

During an ice age as water gets trapped in expanding ice, the entire water cycle stabilises at much lower rates of flux than during an inter-glacial period. Evaporation (due to absorption of solar energy) is the primary force which drives the water cycle. During an ice age, rates of evaporation will decrease sharply, precipitation will reduce and the flow of fresh water through rivers and streams back into the seas will reduce as a consequence. Sea levels would drop by up to 150 m from current levels and while currently submerged land will be exposed, desertification of many regions will also take place.

One of the technologies that will be necessary at such a time will be for the extraction of fresh water from sea ice.

Bohai Bay China

Bohai Bay China

The Bohai Rim is one of the water-scarce regions in China. But every winter, more than 1 billion m3 of sea ice formed in the sea, about 40% of which distributes within 10 km offshore and is expected to be exploited and utilized as source of freshwater.

They may not be expecting a return to full glacial conditions anytime soon, but perhaps the Chinese are already preparing for another Little Ice Age and the fresh water availability reduction that will undoubtedly cause.

Xinhua reports:

China will soon begin production of large amounts of fresh water through the desalination of sea ice, according university research team and a Chinese company on Tuesday. A research team from Beijing Normal University signed a sea ice desalination technology transfer agreement with Beijing Huahaideyuan Technology Co. Ltd on Tuesday.

The company is expected to be able to produce at least 1 billion cubic meters of fresh water annually by 2023, said Yu Jian, executive president of the company. The salinity of sea ice is between 0.4 percent to 0.8 percent, much lower than that of sea water, which stands at about 2.8 percent to 3.1 percent, said Professor Gu Wei, head of the research team.

The research team has mastered the basic principles and technology of sea ice desalination and developed the equipment to be used in the process, including an ice-breaking platform and an ice-gatherer, he said. The salinity of sea ice water after desalination is 0.1 percent, which meets the national standard. The water can be used in agriculture, by industry and for drinking, he said.

The cost of desalination is expected to fall to 4 yuan per tonne, he said.

China’s sea ice desalination program started in 1996 when Shi Peijun, a professor from Beijing Normal University, realized that low saline ice could ease the water shortage around the Pan-Bohai Bay area in north China, after desalination. The program has received a total of 29.72 million yuan (4.88 million U.S. dollars) from various government departments in the past 18 years.

In winter in high-latitude oceans, there is a great amount of sea ice, which is being recognized as a new resource of fresh water by scientists.

One cold wave is not proof of Global Cooling, but ….

January 9, 2014


One cold wave is not proof of Global Cooling,

Even if polar ice is now steadily increasing,

But a quiescent Sun is in another Minimum,

And AGW theory suffers a diverticulum,

For Climate Change is changing to a Cooling from a Warming.

From CBN News:

Global Cooling: Is an Ice Age Coming?

The fact that Arctic ice is growing may not be the good news that it seems to be. There are signs that the Earth is entering a very unpleasant cooling period. Sunspot activity remains very low.

“The sun has been very unusual for almost 15 years now,” Jens Pedersen, senior scientist at the Denmark’s Technical University, said.

Pedersen said the sun recently reached solar maximum and that there should be a lot of sunspot activity, but there isn’t.

“We have to go back 100 years to find a solar maximum that was as weak as the one we are in right now,” he told CBN News. “And the recent solar minimum…one has to go back 200 years to find one that was as weak.”

The last time the sun was this quiet, North America and Europe suffered through a weather event from the 1600s to the 1800s known as “Little Ice Age,” when the Thames River in London regularly froze solid, and North America saw terrible winters. Crops failed and people starved.

Pedersen said climate scientists know the Earth stopped warming 15 years ago. But the United Nations Intergovernmental Panel on Climate Change, of which Pedersen is an expert reviewer, suppressed a recent report from its own scientists that the U.N.’s climate model has been proven wrong.

“In particular one of the issues has been why global warming has stopped during the last 15 years, and climate scientists were very frank that the climate models do not match the climate we observe,” Pedersen said.

But politicians removed that embarrassing finding from the final draft.  It’s as if the alleged danger from climate change can’t be wrong because it is now too important.

It has become a political movement, a cash cow for climate scientists and environmental groups, and a way for world leaders to control economies and people.

“It’s a political agenda,” Dan Gainor, vice president of business and culture at the Media Research Center, said. “When you look at what the government will be able to do with climate change, it gives them (access) into every aspect of our lives.” ….. 

Related: https://ktwop.wordpress.com/tag/landscheidt-minimum/

Ice Age must be imminent: UK government predicts no cooling for “several centuries”

November 1, 2013

We are in a global cooling cycle and this may be a:

  1. a regular c. 30 year warming/cooling cycle influenced heavily by the multi-decadal ocean cycles, or
  2. another Little Ice Age – dominated by the solar sunspot cycles –  with the current Landscheidt Minimum comparable to the Dalton or the Maunder Minimum, or
  3. the ending of this interglacial  with a gradual return to glacial condition.

If anything can ensure that we are in for another Ice Age it must be this rather inane statement by the UK Parliamentary Under-Secretary of State, Department of Energy and Climate Change (Baroness Verma) when answering a question in the House of Lords:

All of the climate models and policy-relevant pathways of future greenhouse gas and aerosol emissions considered in the Intergovernmental Panel on Climate Change’s (IPCC) recent Fifth Assessment Report show a long-term global increase in temperature during the 21st century is expected. In all cases, the warming from increasing greenhouse gases significantly exceeds any cooling from atmospheric aerosols. Other effects such as solar changes and volcanic activity are likely to have only a minor impact over this timescale.

With regard to future glaciation the timescales are very long. Changes in the Earth’s orbit are considered to have driven the glacial cycles that have occurred every 100,000 years approximately, during the past one million years. The British Antarctic Survey has advised that the Earth is about halfway through the current interglacial period and the onset of the next glaciation is not expected for around 10,000 years at least. Although a future extensive glaciation would have huge geopolitical consequences, the transition into such a state would be slow, allowing for adaptation over many generations.

The slow changes in the Earth’s orbit are not, however, expected to cause any net global cooling over the next several centuries, which will be dominated by a warming global climate due to greenhouse gas emissions.

Baroness Verma’s faith in the IPCC and her religious adherence to global warming orthodoxy is touching. But the only thing we can be absolutely certain about is that the UK Government and Baroness Verma have surely got it wrong. In fact, the propensity of Baroness Verma to get (all) things wrong would suggest that glaciation has already started.

Probability of Maunder-like minimum increases

October 28, 2013

I have been of the opinion for some time now that the current Landscheidt Minimum that we are in has a reasonable probability of reaching Dalton Minimum conditions and even developing into a Maunder-like minimum. The Landscheidt Minimum has yet to be officially named. It seems increasingly probable that we are in for some 20 – 30 years of  global cooling. This has not been the view of the global warming enthusiasts who don’t  much believe in the Sun. But now some heavy-weight opinions are also giving more credence to the possibility of a Maunder-like Minimum. We have currently reached solar maximum in Solar Cycle 24 and SC24 and the coming SC25 are comparable to SC’s 4,5 and 6 which corresponded with the Dalton Minimum. Note that the numbering system for Solar Cycles only starts after the Maunder Minimum.

Paul Hudson has been talking to Professor Mike Lockwood:

It’s known by climatologists as the ‘Little Ice Age’, a period in the 1600s when harsh winters across the UK and Europe were often severe. The severe cold went hand in hand with an exceptionally inactive sun, and was called the Maunder solar minimum. 

Now a leading scientist from Reading University has told me that the current rate of decline in solar activity is such that there’s a real risk of seeing a return of such conditions. I’ve been to see Professor Mike Lockwood to take a look at the work he has been conducting into the possible link between solar activity and climate patterns. 

According to Professor Lockwood the late 20th century was a period when the sun was unusually active and a so called ‘grand maximum’ occurred around 1985. Since then the sun has been getting quieter. By looking back at certain isotopes in ice cores, he has been able to determine how active the sun has been over thousands of years. 

Following analysis of the data, Professor Lockwood believes solar activity is now falling more rapidly than at any time in the last 10,000 years. He found 24 different occasions in the last 10,000 years when the sun was in exactly the same state as it is now – and the present decline is faster than any of those 24. Based on his findings he’s raised the risk of a new Maunder minimum from less than 10% just a few years ago to 25-30%. And a repeat of the Dalton solar minimum which occurred in the early 1800s, which also had its fair share of cold winters and poor summers, is, according to him, ‘more likely than not’ to happen. He believes that we are already beginning to see a change in our climate – witness the colder winters and poor summers of recent years – and that over the next few decades there could be a slide to a new Maunder minimum. 

It’s worth stressing that not every winter would be severe; nor would every summer be poor. But harsh winters and unsettled summers would become more frequent. 

Professor Lockwood doesn’t hold back in his description of the potential impacts such a scenario would have in the UK. He says such a change to our climate could have profound implications for energy policy and our transport infrastructure. Although the biggest impact of such solar driven change would be regional, like here in the UK and across Europe, there would be global implications too. ……… 

Recent solar activity (Wikipedia) showing the Maunder and Dalton minima

2013 was a “good” year for the cryosphere – but could it be the beginning of the end of this interglacial?

October 8, 2013

According to the NSIDC – which is an important part of orthodox officialdom – 2013 was a better year for the cryosphere since:

“This summer, Arctic sea ice loss was held in check by relatively cool and stormy conditions. As a result, 2013 saw substantially more ice at summer’s end, compared to last year’s record low extent. The Greenland Ice Sheet also showed less extensive surface melt than in 2012. Meanwhile, in the Antarctic, sea ice reached the highest extent recorded in the satellite record”.

What makes for “good” or “bad” depends upon what the fears are. If global warming is the fear then – as the NSIDC states – it was a good year. But if a cooling cycle or even a coming ice age is the fear then the increasing ice extent, the short summer, the extended winter last year and the increased snow cover in the Northern Hemisphere are all just early warning signs of what is to come.

We don’t know if we are in:

  1. a run-away global warming period (as the global warming orthodoxy will have us believe), or
  2. a series of global warming and cooling cycles, each about 20 – 30 years long and responding to the decadal ocean cycles, or
  3. the beginning of the end of this interglacial (which is overdue).

The global warming pause of the last 17 – 18 years suggests that “run-away” global warming is unlikely. The slight decrease in global temperatures over the last 7 – 8 years is not conclusive but is also evidence that the effect of increasing carbon dioxide on global temperature is far from certain. Even if it exists it is very small  and is clearly not yet properly understood. Catastrophe scenarios may attract funding but reduce the credibility of the doom-sayers.

If we are just in a regular cooling cycle then the increasing ice level is nothing to be afraid of. Even if 2 or 3 decades of cooling give us another Little Ice Age, it will be followed by a warming cycle. It will not necessarily mean the start of the end of the current interglacial. But it will mean 20 – 30 years of cooling and the increased use of fossil fuels will be required. Fracking and methane hydrate recovery from the deep sea will be needed along with the continued – and increased – mining of coal. Wind and solar energy can play their little part in the niches that they are suitable for. Nuclear energy will have to make a come-back.

But if the Earth is now responding – by mechanisms unknown – to the Milankovitch cycles – and has started its many thousands year journey into glacial conditions, then we would be well served by developing the strategies and technologies for prospering in such times. We will gradually lose habitat in the North to growing ice sheets but we will gain new habitat as the sea level sinks. But these changes will take place over many generations (50 – 100) and we will have time to adapt. One lost generation – as the last 20 years of global warming hysteria will be – will be of little consequence. Humans have lived and prospered through glacial conditions before and will again. One big difference will be the availability of affordable and abundant energy which gives us the ability – not to stop the advance of the ice sheets – but to be able to continue to access resources and minerals under the ice sheets. We may even have colonies living on top of the shallower ice sheets. But there will also be new opportunities. The increase of habitat as the sea levels drop (by upto 150m) will be in exceptionally fertile areas for food production. Mineral and energy resources currently under the sea will become even more accessible. As with the last glacial period it will probably be a period in which human ingenuity is challenged and innovation will flourish.

The coming of a new glacial period will be no catastrophic change. We will have plenty of time to adapt. And in the 1,000 or 2,000 years it will take to establish glacial conditions, humans will probably have found new frontiers and established new colonies in space. And in 50 or 100 generation humans will continue to evolve. The humans coming out of the next glacial will not be quite like us.

Little Ice Age could well have resulted from reduced solar activity

October 4, 2013

This paper is particularly interesting because the senior author, Thomas Stocker, is the Vice-Chair of the IPCC and presented the summary of AR5 at the Press Conference last week!!

It is very strange then that the IPCC is so nonchalant about solar effects. In any event whatever the various climate models say, the Landscheidt Minimum is here and global cooling will continue for the next two decades or so. As The Register puts it.
” There’s been criticism for the Intergovernmental Panel on Climate Change (IPCC) over its latest AR5 report from many quarters for many reasons. But today there’s new research focusing on one particular aspect of that criticism.The particular part of the IPCC’s science in question is its accounting for the effects of changes in the Sun on the climate of planet Earth. Many climatologists have long sought to suggest that the effects of solar variability are minor, certainly when compared to those of human-driven CO2 emissions. Others, however, while admitting that the Sun changes only a very little over human timescales, think that it might be an important factor. This matters because solar physicists think that the Sun is about to enter a “grand minimum”, a prolonged period of low activity. 
The current 11-year peak in solar action is the weakest seen for a long time, and it may presage a lengthy quiet period. Previously, historical records suggest that such periods have been accompanied by chilly conditions on Earth – perhaps to the point where a coming minimum might counteract or even render irrelevant humanity’s carbon emissions. The “Little Ice Age” seen from the 15th to the 19th centuries is often mentioned in this context.
Lehner, Flavio, Andreas Born, Christoph C. Raible, Thomas F. Stocker, 2013: Amplified Inception of European Little Ice Age by Sea Ice–Ocean–Atmosphere Feedbacks.  J. Climate26, 7586–7602.
doi: http://dx.doi.org/10.1175/JCLI-D-12-00690.1
The University of Berne press release writes:
The study that was realized at the OCCR shows that volcanic eruptions and reduced solar radiation caused global cooling between the thirteenth and the fifteenth centuries. The resulting accelerated formation of sea ice in the Northern Seas triggered a positive feedback process that shaped the Little Ice Age. The winter weather in Europe is largely governed by the so-called North Atlantic Oscillation (NAO). ……. Until now, the NAO was believed to be jointly responsible for the cooling in the early fifteenth century along with volcanic eruptions and weakened solar radiation. The subsequent Little Ice Age continued into the nineteenth century. Now, however, Bernese climate researchers Flavio Lehner, Andreas Born, Christoph Raible and Thomas Stocker reveal that the Little Ice Age was also able to take its course without the influence of the NAO, driven purely by the consequences of strong and frequent volcanic eruptions at the time, a reduced solar radiation, or both together.
Using simulations on the CSCS supercomputer “Monte Rosa”, the climate researchers searched for a feedback process that was capable of triggering the Little Ice Age.
….. For the scientists, the fact that all the slightly altered, realistic simulations and the synthetic ice simulation yielded consistent results is solid proof that the Little Ice Age was primarily governed by external triggers. Volcanic activity and less solar radiation initially caused an increase in sea-ice formation independently of atmospheric circulation. Due to the cooling, the mean sea level pressure gradually increased over the Barents Sea, which enabled the cold air to reach Europe. “However, this pressure response is clearly a delayed reaction of the atmosphere to the preceding processes in the ocean,” says Raible.
Abstract: The inception of the Little Ice Age (~1400–1700 AD) is believed to have been driven by an interplay of external forcing and climate system internal variability. While the hemispheric signal seems to have been dominated by solar irradiance and volcanic eruptions, the understanding of mechanisms shaping the climate on a continental scale is less robust. In an ensemble of transient model simulations and a new type of sensitivity experiments with artificial sea ice growth, the authors identify a sea ice–ocean–atmosphere feedback mechanism that amplifies the Little Ice Age cooling in the North Atlantic–European region and produces the temperature pattern suggested by paleoclimatic reconstructions. Initiated by increasing negative forcing, the Arctic sea ice substantially expands at the beginning of the Little Ice Age. The excess of sea ice is exported to the subpolar North Atlantic, where it melts, thereby weakening convection of the ocean. Consequently, northward ocean heat transport is reduced, reinforcing the expansion of the sea ice and the cooling of the Northern Hemisphere. In the Nordic Seas, sea surface height anomalies cause the oceanic recirculation to strengthen at the expense of the warm Barents Sea inflow, thereby further reinforcing sea ice growth. The absent ocean–atmosphere heat flux in the Barents Sea results in an amplified cooling over Northern Europe. The positive nature of this feedback mechanism enables sea ice to remain in an expanded state for decades up to a century, favoring sustained cold periods over Europe such as the Little Ice Age. Support for the feedback mechanism comes from recent proxy reconstructions around the Nordic Seas

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