Past climate in the north Atlantic: a new paper on old mud

by Jane Bunting (@DrMJBunting)

Almost twenty-five years ago, in the late Autumn of 1990, I travelled to Orkney with my supervisor Keith Bennett to collect the first sediment cores for my PhD research project. Results from analysis of one of the core sequences have just been published in the journal Quaternary Science Reviews (Whittington et al. 2015 - can be accessed here if you have a subscription, or email/tweet me).  This isn’t quite as bad as it sounds – I published my PhD findings from the site in 1994, focusing on what the pollen preserved in the sediments could tell us about the vegetation history of the islands since the last Ice Age (see here for Michelle's post on pollen analysis) – but rather reflects how long it can take to acquire data and write up collaborative research which is not supported by a single, comprehensive research grant, just by interested academics. 

Location of Orkney in the North Atlantic (bad screengrab from google maps)

Orkney is an archipelago situated to the north of mainland Scotland, and has a hyperoceanic climate (see map left: the google marker shows the location of Crudale Meadow, my study site, on the west of Mainland, the largest island). This means that the environment is very strongly affected by north Atlantic weather systems, and therefore that sediments accumulating in basins on the islands potentially contain a sensitive record of past climate oscillations. This latest paper focuses on the record of past climate, and particularly on abrupt changes in climate, recorded by sediments spanning the period from about 14000 years ago to about 8000 years ago. This covers the end of the last ice age and the beginning of the current warm period. 

Crudale Meadow is today a valley mire, a low point in the landscape supporting a waterlogged plant community of reeds, sedges and other fen species. However, coring down into the sediments showed that this wasn’t always the case. Under about two metres of tough, fibrous peat full of the preserved stems of the reeds and sedges, we found a pale cream-coloured mud, containing obvious fragments of shells. This was lime mud, which forms in shallow lakes and ponds when the water flowing in is alkaline – it’s closely related to the flaky stuff that clogs up kettles in a hard-water area. In Orkney, most former and present lakes deposit acidic muds with minimal carbonate content, but in some places the till left behind by the retreating glaciers contains lumps of chalk, which dissolve in rainwater filtering through the soil, raise its pH, and lead to the formation of lime mud through chemical reactions within the lakes and ponds. 

As a beginner pollen analyst, I was not very fond of those lime muds –they don’t preserve pollen as well as acidic lake muds – but for researchers looking to reconstruct the palaeoclimate of the North Atlantic they were actually very useful. This is because of a process called isotopic fractionation (click on this link for more information about isotopes and climate reconstruction). Oxygen naturally occurs in two forms, one lighter (oxygen-16) and one heavier (oxygen-18), and the ratio between these forms in the water that arrives through rainfall varies according to factors such as the source of the rain and the regional temperature. The carbonate part of the chemical structure of lime muds includes oxygen molecules from the lake water, and therefore locks in a record of the ratio of isotopes in the water. ‘Reading’ this record allows us to reconstruct past temperature, so when towards the end of my PhD I was asked to share my core with a larger team who had the capacity to carry out the analyses, I was interested to see what they’d find. We didn’t realise it would be quite such a long wait…

 The figure below is redrawn from the article, and summarises the reconstructed temperature trends. Looking from left to right, we’re moving back in time. The dashed black line shows a smoothed long term trend and the jagged blue line shows the underlying data. The blue boxes identify periods which are statistically unusually cold, and seem to reflect short-lived climate changes. 

Redrawn from Whittington et al. 2015. Oxygen isotope ratios from Crudale Meadow (see post for details)

Most of these can be found elsewhere in the North Atlantic, in sediment records and even in the Greenland ice cap record, but one is apparently not yet described from other records, and the record is one of the best demonstrations of abrupt events early in the current warm period yet found in Britain. By looking at the remains of molluscs preserved in the alkaline sediments, at the pollen record, and at other sedimentological evidence, we are also able to explore the extent to which these shorter climate episodes affected life in and around the basin.  Climate is the longer-term average of the weather, and in Orkney, you can often literally see changes in the weather blowing in across the sea. Locals say ‘if you don’t like the weather, wait half an hour’ or ‘there is one season a year, but four seasons a day’. Climate records like the one presented in this new paper show long term trends – the proportions of rain and sun, the mean of temperatures over multiple years, the natural variability of the complex and dynamic dance of atmosphere and ocean that creates climate and weather. Twenty five years is roughly equivalent to one sample in the results presented here, even if it seems a long time from a human perspective, or a publishing one!

 

View from Yesnaby, looking west (photo M. Farrell 2007)

After a long, wet, muddy day in 1990 collecting sediment cores from Crudale, Keith and I drove a mile or so to the nearby cliffs at Yesnaby and ate a very late packed lunch watching the dusk settle over the rolling Atlantic, nothing but ocean between us and north America. At the time I had no idea that there was a record of 6000 years of the climate over that ocean in the core-box, just a hope that there was enough data for a chapter in a PhD. As I write this, a PhD student at Royal Holloway (Rhys Timms) is analysing a new core from another of my PhD sites, Quoyloo Meadow, using the remains of non-biting midges along with other methods to further investigate the climate changes at the end of the last ice age. I wonder what new techniques will have come along by 2040, another 25 years in the future? 



Bunting, M.J 1994.  Vegetation history of Orkney, Scotland: pollen records from two small basins in west Mainland.  New Phytologist 128 771-792
 
Whittington, G., Edwards, K.J., Zanchetta, G., Keen, D.H., Bunting, M.J., Fallick, A.E. and Bryant, C.L. (2015). Lateglacial and early Holocene climates of the Atlantic margins of Continental Europe: stable isotope, mollusc and pollen studies from Orkney, Scotland. Quaternary Science Reviews 122, 112-130

Guest post: EU- China Partnerships on Climate Change – Are They Effective?

by Professor David Gibbs, Department of Geography, Environment and Earth Sciences, University of Hull.

Later this year in December 2015, the next Climate Conference will be held in Paris. This will be the 21^st Conference of the Parties (COP) to the UN Framework Convention on Climate Change.  Once again, 196 governments will meet to try and agree a new climate change agreement for the coming years.  Previous meetings have been notable for their lack of agreement and for the fact that the world’s top two contributors to carbon emissions – the USA and China – have been opposed to action.  For China, the flip side to its increasing economic importance and role as the ‘workshop of the world’ - exporting consumer goods to Europe and the US - has been its growing contribution to world carbon emissions as domestic power demands have been met by opening new coal-fired power stations.  Not only has this led to international concern, but the resulting pollution and decline in air quality has led to concerns and protest within China itself. 

image from Asia-Europe foundation here

Recently, I’ve been working on a project funded by the British Academy and the Sino-British Fellowship Trust looking at how the European Union and Chinese government have been working together to address climate change.  Obviously the two are already connected in other areas – this is perhaps most evident in terms of economic and trade links.  China is now the EU’s second largest trading partner and fastest growing export market, while the EU is China’s biggest trading partner as well as the most important export destination.  The focus of my research though was not on the economic challenges to the West or even the global environmental consequences from China’s recent development, but in examining the two-way benefits that partnership between the EU and China could bring on climate change.  The EU sees itself as a world leader in action on emissions and has sought to work with China through negotiation and joint working.  As an EU official said to me – “involvement in climate change talks involves a lot of finger pointing and blaming which doesn't work with China - informal negotiations work much better than this”.  Through interviews with Chinese and EU officials and politicians in Beijing and Brussels, I was interested in seeing how climate change partnership policy and joint working has evolved.  In addition, I was also keen to examine whether the Partnership has served China’s domestic sustainable development agenda, as well as the EU’s ambitions for global leadership on climate change.

Through looking at the UN’s Clean Development Mechanism (CDM) it appeared that the EU and China by working together initially stolen a march over other players, especially the USA.  The CDM allowed developed countries to offset emissions through investment in CO₂ mitigation projects and developing countries to receive payment for voluntary efforts to reduce emissions. As a developing country, China has not so far had specific quantitative targets for CO₂ reductions, but needs to promote the CDM in cooperation with western industrialised countries.  The EU and China were leading stakeholders in CDM – China was the dominant host country, whilst member states of the EU collectively became the leading investing parties for CDM projects. By default, CDM projects served as a new opportunity for further developing EU-China relations in which both sides would gain. The benefits were not simply in terms of reducing carbon emissions.  Interviews with EU officials in both China and Brussels showed that an important outcome for them has been the development of greater trust and the opportunity for policy learning.  For EU officials, China's involvement in CDM had made it much easier to start the debate between the two sides around climate change issues. Thus engagement with the CDM by Chinese policy makers and businesses has led to growth of climate change know-how in China. In particular, the CDM has helped China make the step towards seeing how these types of market instruments could work and this has formed the basis of joint working on developing China’s Emissions Trading Scheme, informed by EU experiences.  The people I spoke to emphasised that this has to be a genuine two-way process – Chinese officials will be involved in dialogue and discussion with their EU counterparts, but (understandably) are not keen on being told what they should do in policy terms or how to do it.

Despite these initial successes, it appears to be an uphill struggle for the objectives of the EU-China Partnership on Climate Change to be achieved. On the one hand, the extent to which the CDM can be used as a new market tool contributing to China’s sustainable development and low carbon growth by generating additional renewable energy is very limited.  While CDM wind farms have mushroomed in the remote regions of China such as Inner Mongolia, and the north-eastern and north-western provinces, these are thousands of kilometres away from the economic heartland and power demands of the export-producing eastern and south-eastern regions. In the absence of an advanced and efficient grid infrastructure, long-distance transport of electricity leads to significant loss of energy and due to the limitations of storage technologies, electricity produced by wind farms in remote areas cannot be stored locally and this makes it difficult for grid operators to cope with the uneven pattern of energy supply.

The initial enthusiasm of the EU to become a world leader in climate change may therefore not prove viable in the long run and we can question how effective the EU approach of dialogue and ‘soft power’ has been.  Despite their past differences, in November 2014 China and the US signed a bi-lateral agreement to reduce their greenhouse gas emissions which suggests that despite all the years of informal efforts by the EU, it has been less effective than the US in encouraging China to take action.  Not only have the US and China agreed to reduce their own emissions, but their agreement may break the deadlock that has affected previous climate talks.  In their common mission of searching for low carbon growth whilst mitigating climate change, the EU and China will continue to be constrained by their own vested interests, which have been responsible for diluting their partnership.  China’s further rise as an industrial and economic power, which is beyond doubt, will pose new challenges to its already troubled trade relations in the renewable energy market. However, the reality of policy and political disunity within the EU dictates that member states will not hesitate to explore the China market with regard to their own domestic interests and agendas. In the future it is likely that ‘partnerships’, rather than ‘partnership’, will prevail so far as EU-China relations are concerned.

 


This blog post is cross-posted from the British Academy blog, here.

David can be contacted by email at d.c.gibbs@hull.ac.uk, and you can find out more about his work from his university web page here.

Five amazing extinct creatures that aren't dinosaurs

By Charlotte Stephenson, Department of Geography, Environment and Earth Sciences, University of Hull

The release of Jurassic World has reignited our love for palaeontology. Many of us share a longing to understand the dinosaurs that roamed the Earth long before we arrived. But palaeontology is a discipline much broader than this.
Dinosaurs dominated the land for 135 million years, but what happened during the rest of the Earth’s 4.6 billion-year history? The role of palaeontologists past and present has been to unravel the mysteries of life on Earth, and in doing so they’ve found a lot more than just dinosaur bones.

1. The spiky-backed ocean dweller

Right side up? Natural Math/flickr, CC BY-SA

Hallucigenia was discovered when a 508 million year old fossil was found in 1911 in the world-famous Burgess Shale fossil site in Canada. Since then, our understanding of this ocean-dwelling creature has changed dramatically.
Its age means it falls into the geological Cambrian period, a pivotal moment for all life on Earth when complex lifeforms started to rapidly evolve. When originally described, Hallucigenia was first thought to have walked along the ocean floor on spiny legs and used tentacles on its back to catch food. Palaeontologists also argued over which end was its head.
But when a similar fossil was found in China, Hallucigenia was re-examined. Palaeontologists then discovered that its “legs” were actually protective spines on its back, and the tentacles formed two rows on its underside enabling it to “walk”. Researchers are still debating many of the features of Hallucigenia today, more than 100 years after it was discovered.

2. (Almost) the first fish out of water

Best foot forward Nobu Tamura, CC BY-SA

100 million years on from Hallucigenia, aquatic habitats were thriving, but life on land was still in its earliest stages. Tiktaalik, part fish, part four-legged animal, is believed to be the first creature to develop characteristics that would help animals move out of the water and on to land.
It had gills, fins and scales like a fish, but also evolved features such as a flexible neck and a reptile-like head and lungs, beneficial for life on the ground. Fossils also show Tiktaalik had long fins that acted as legs, meaning it could “walk” along riverbeds as well as swim.

3. The giant Scottish scorpion

Sting in the tail Nobu Tamura, CC BY

Pulmonoscorpius kirktonensis, a 70cm-long scorpion, lived in what we now know as Scotland 340 million years ago. At a length greater than that of the average pet cat, this terrifying creature used its tail to catch and kill its prey.
Pulmonoscorpius also had unusually large eyes compared to its modern relatives, so most likely hunted during daylight hours. Scorpions shed their skin as they grow, so fossils of both the skin and the animal itself have been found.

4. The spiral-lipped shark

Giving some lip Dmitry Bogdanov, CC BY-SA

Helicoprion, a shark-like fish alive during the Permian (290 million years ago), had a rather unique dental structure. With a face that baffled palaeontologists for years, this creature had a lower jaw made up of a spiral of teeth, known as a tooth-whorl.
Modern sharks are able to lose and replace their teeth, but Helicoprion kept them all, with older teeth hidden within the inner layers of the tooth-whorl. When it caught its prey (most likely relatives of the squid), it would close its mouth and rotate its tooth-whorl to shred its catch.

5. A tiny, drunk horse

Gone to that big horsey ring in the sky Daderot

The Messel Oil Shale, once a volcanic lake in Germany, has plenty to offer the world of palaeontology. Eurohippus messelensis, was a miniature horse (the size of a modern day fox) originally thought to have died from eating fermented berries and in a drunken stupor, fallen into the lake. It’s now believed the 47 million year old horse actually died from inhaling toxic gas occasionally released from the depths of the lake.
But the misfortune continues, as it was later discovered that the horse was pregnant. Palaeontologists used high-resolution microscopes to identify the bones of a foal within the adult Eurohippus, improving our understanding of foetal development in these animals.
Palaeontology is a career firmly seated on many childhood wish-lists alongside movie stars and astronauts, and rightly so. But it’s important to remember there’s a lot more to palaeontology than the dinosaurs. This list is just the start.


Charlotte Stephenson is PhD candidate, palaeoenvironments & palaeobotany at University of Hull.

This article was originally published on The Conversation. Read the original article.

Five incredible old English homes built by women

by Briony McDonagh (@BrionyMcDonagh)

The initials ‘ES’ on the parapets are those of Elizabeth Talbot, who built Hardwick Hall. adteasdale, CC BY-SA

We tend to think of the landowners, architects and builders of the past as men, just as we do its politicians, rulers and artists. Women rarely get a look in. But research is uncovering more and more historical examples of women who played a leading role in society, politics or the arts – and the public, it seems, are fascinated. Take Amanda Vickery’s recent series on The Story of Women and Art for example, or the idea that Bach’s wife composed some of his finest works.

Likewise, my ongoing AHRC-funded research project on 'Elite women and the agricultural landscape' is revealing that women owned far more land than was once thought – and this despite the fact that before the late 19th century the law made it difficult for married women to own property of any sort. As a result, we’re also recognising that women played a far greater role in designing, commissioning and building country houses, gardens and parklands than was once imagined.

The nature of surviving historical sources means that women’s contributions are often poorly recorded, but there are exceptions – and we’re uncovering ever more of them. So as the National Trust and English Heritage open their properties to the public for the summer, why not pop along and visit a country house where the influence of a woman in its past is plain to see? Here are a few suggestions to get you going.

 

Temple Newsam

This vast Tudor/Jacobean house stands in grounds near Leeds that were landscaped by Capability Brown. Originally built for Thomas, Lord Darcy (who came to a grizzly end after rebelling against Henry VIII), the house was remodelled in the late 18th century by Frances Ingram, Viscountess Irwin, a highly involved female patron.

Her whopping £60,000 dowry – worth more than £7m in today’s money – had been used to fund improvements to the house and grounds in her husband’s lifetime, but it was only after his death that she was really bitten by the building bug. As a widow, she demolished and rebuilt the entire south wing “for the sole pleasure in building [it] up again” – as she put it – and redecorated much of the rest of the house.

Temple Newsam. theracephotographer, CC BY-SA

 

 

Weston Park

Weston Park is a Palladian-style mansion in Staffordshire largely designed and built by Lady Elizabeth Wilbraham in the 1670s. Weston was her childhood home and while her husband was the legal owner, Wilbraham seems to have retained considerable control of the property during her marriage. We know she was heavily involved in both the design of the new hall and the financial management of the building work, and she’s often hailed as the architect of the house.

 

 

A la Ronde

An unusual 16-sided house near Exmouth, A la Ronde was designed by cousins Jane and Mary Parminter in the 1790s. Somewhat unusually for women at the time, the Parminters had spent nearly a decade travelling in Europe and were apparently inspired by a visit to the octagonal chapel of San Vitale at Ravenna (Italy). The Exmouth property was small and there was no tenanted agricultural land, but the cousins also designed and built a chapel, almshouses and school in the grounds just as much wealthier women did on their estates.

A la Ronde. charliedave, CC BY

Hardwick Hall

Built by Elizabeth Talbot, countess of Shrewsbury (better known as Bess of Hardwick) Hardwick Hall is perhaps the most well-known country house in Britain built by a female landowner. Bess was born into a minor gentry family in Derbyshire, but was a woman of great ambition: she married four times, and the property left to her by her four dead husbands eventually made her the richest woman in England.

She oversaw the building of Chatsworth Hall from about 1550 onwards, and later built not one, but two, grand houses at Hardwick. Soon after finishing the Old Hall in 1591, she began to build the adjacent New Hall, a vast house known for its glittering glass façade and unusual floor plan. Visitors should look out for Bess’s initials “ES”, highlighted for posterity in parapets of the towers and elsewhere in the house.

 

 

Belvoir Castle

Elizabeth Manners, fifth duchess of Rutland, was credited by contemporaries both as the driving force behind the rebuilding of Belvoir Castle in the 1820s and the principal manager of the family’s Leicestershire estate. As one friend noted at the duchess’s death in 1825, the duke “did nothing for himself, and his estates, his horses, his family, everything was under her rule”.

While it’s unclear how far this was a fair assessment of the duke’s contribution, the duchess certainly oversaw landscaping works to the castle grounds and took an active interest in the agricultural aspects of the property, including designing a model farm. She also made improvements to Cheveley Park (Suffolk) in the early 1800s, oversaw the building works at York House on the Mall for her lover the Duke of York and drew up designs for a new palace for George IV.

The list of such houses is growing. So, while undoubtedly disadvantaged both by the law and by societal expectations of their gender, the wives, widows and single women of the past could – and did – build grand country houses. Not all female landowners had access to the money and resources necessary to re-build or significantly extend their country residence of course, but others re-planned gardens and parklands or improved the large agricultural estates which lay beyond the park boundaries. In doing so, these women and others like them had a far greater impact on the landscapes of early modern and Georgian England than history has so far acknowledged.

Briony McDonagh is Lecturer in Human Geography at University of Hull.

An earlier version of this article was published on The Conversation. Read the original article.