Issue 94

May/June 2007

Contents

news

Unique decorated jet lozenge from Suffolk matches Stonehenge gold

Heritage white paper praised: but who will pay for it?

Classic jadeite axe may leave UK

What was Roman interest in Silbury Hill?

New dates

In Brief & Phase 2

features

Ringed with the wrecks of slave ships: The Atlantic slave trade
Buy, sell, trade, drown. Jane Webster asks what archaeology can bring to the story

Churches face East, don't they?
Church alignments. Do churches face sunrise on saints' days? Ian Hinton surveys

Excavating Dover's Medieval seasfarers
Keith Parfitt and Barry Corke discover a fishing community

on the web

Recommended websites
Online glossaries and the CBA's Community Archaeology Forum wiki (CAF)

letters

Views and responses

CBA correspondent

Campaigns, comment and communications from the CBA
Adapting archaeology: Gill Chitty looks at climate change and archaeology in the UK

ISSN 1357-4442

Editor Mike Pitts

CBA correspondent

Adapting archaeology

Gill Chitty looks at climate change and archaeology in the UK

Campaigns, comment and communications from the CBA

In York, where the CBA has its offices, there has been no doubt about the effects of climate change during the last year. The flood barriers and sandbags have been up along the river Ouse for days at a time. But of course it is not just increased flooding to which archaeological sites and historic buildings are vulnerable.

Many other effects of climate change are generally well known now. Paradoxically there will be hotter, drier summers, with increasingly intense episodes of heavy rainfall. Extreme weather events will become more common – damaging buildings, bringingd down trees, causing landslides and inundation. After adjusting for land movements, the average sea level around the uk is rising steadily: it is about 10cm higher today than in 1900 and intensified by storm surges. Research for the UK Climate Impacts Programme shows sea level could rise by 80cm by the end of this century (www.ukcip.org.uk). In 2008 UKCIP will present more detailed information than ever before for understanding climate change here. But from what we know already there are clear indications about the scale and pace of change.

Archaeological losses already caused by coastal erosion and storm damage are self-evidently serious. There are major programmes of archaeological survey and recording in progress all around the UK, in the coastal and intertidal zone and in the seas. These will inform shoreline management plans. Other changes are more complex and it will take time to plan how to manage them. The impact on soil quality and erosion will be significant, and critical for archaeology when vegetation cover is weakened by drought or overgrazing. Uplands, which contain some of the best preserved prehistoric landscapes, are particularly sensitive. In the Lake District, which enjoys the heaviest rainfall in England, research shows an increase in areas of bare soil from 4% in 1970 to 8% in 2000. Prehistoric upland landscapes are also vulnerable to migration of vegetation, such as bracken and scrub, to higher altitudes as temperatures and growing seasons increase.

It is not all bad news. Peat bogs are valuable carbon sinks and their conservation will become a priority, making a significant contribution to managing carbon. There is, we are told, more carbon in UK peat soils than the woodlands of Britain and France combined. Decaying peat is a significant source of greenhouse gases, so good peatland management makes good sense for the global environment, while safeguarding an important archaeological resource.

The effects of increased cycles of drought and flooding will alter the conditions for archaeological preservation. Increases in extreme wetting and drying episodes are likely to be as damaging for the structural stability and fabric of historic buildings as they are for buried sites. The EC "Noah's Ark" research project is mapping the vulnerability of cultural heritage to climate change in Europe and its report will be published in June. Its preliminary findings are sobering and now available online (noahsark.isac.cnr.it).

The direct impacts of climate change have been acknowledged for some years but the indirect effects are increasingly a challenge too. For archaeology these will be due largely to changes in land use, as we becomes less reliant on fossil fuels and manage flood risks and changing coastlines. There will also be pressure to adapt historic buildings for energy efficiency.

Farming is adapting to extended growing seasons and new markets for biomass and bioenergy crops. Whatever happens to the agricultural economy has a big effect on the historic environment – 70% of the UK's land area is under farm management. It may revitalise, as favourable climatic conditions extend northwards and droughtstricken European producers are unable to supply demand. Monoculture for bioenergy could transform the landscape; a return to intensive arable farming would have an obvious impact on rural archaeology. On the other hand, as DEFRA suggests, farming could become "a net environmental contributor, with subsidy tied to delivering environmental public goods" which could include beneficial management of archaeological sites.

So how are we responding to this to safeguard archaeology? Much is already being invested in improving understanding of the threatened intertidal and coastal zone and in researching effects on in situ preservation. Off-shore development for wind and tide energy is a large growth area, demanding new techniques and approaches. Clearly there will need to be more preparedness for rapid response to sudden episodes of damage and erosion. We also need to pool and focus new research. There could be more joint-working in partnership with the wider environmental sector and sharing of experience to understand better the implications of changes and successful steps to minimise impacts. As a contribution to this, the CBA is organising a day conference in July, with a followup session at the Institute of Field Archaeologists' conference in April 2008.

It is the sheer scale and speed at which the changes may take place that will be the biggest challenge. The "polluter pays" principle has served archaeology well, but in the case of climate change it seems clear that the "polluter" is global carbon emission. Who pays for that? We can expect that resources will continue to be found to mitigate the losses of the most important sites and buildings and to "hold the line" in some significant places. The real cost may well be the unrecorded loss of a myriad of more common-place sites and historic places. There could surely be an important role here for local communities and groups?

In Scotland, the "Shorewatch" project, managed by SCAPE (Scottish Coastal Archaeology and the Problem of Erosion), is a great example of how professional archaeologists have come together with local archaeological groups and their communities, in this case to meet the challenge of Scotland's fast eroding coastline (www.shorewatch.co.uk). Similar projects are running in other parts of the UK, with local groups monitoring and recording sites or doing routine maintenance to keep them in good condition.

Climate change may be the greatest opportunity for collaboration across the archaeological community we have ever had. There is huge scope for local participation in observing, recording and off-setting the impacts over the next generation. To be honest, this may be the only way that we can deal with the scale of the challenge.

Adapting Archaeology: Foresight for Climate Change, a day conference held jointly by the CBA and UCL's Centre for Sustainable Heritage, is at the British Academy, London on July 10. See the CBA's conservation pages for more information on all of these issues: www.britarch.ac.uk/conserve/index.html. Take part in SCAPE's photographic competition to raise awareness about climate change and archaeology in Scotland: www.scapetrust.org/ctc. For Inter-governmental Panel on Climate Change see www.ipcc.ch. Gill Chitty is the CBA's Head of Conservation

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