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Welcome to the British Irish Council (BIC) website for
“Scenarios of climate change for islands within the BIC region”

At the first British-Irish Council Summit it was agreed that the UK Government would take responsibility for advancing work on the Environment and agreed to take forward work on a number of specific areas of interest to Members. This included the establishment of a subgroup on climate change impacts and adaptation which was set up to:

• Exchange national information on the impacts of climate change and adaptation between the BIC member countries.

• Co-operate on areas of mutual interest, with the view to developing a fuller understanding and greater awareness within and between the BIC countries of the vulnerability to climate change and how they might adapt.

A key output of the group’s activities are the BIC Climate Change Scenarios. These will help improve our understanding of the impacts of climate change in the different BIC administrations (particularly the islands), so that we can be in a better position to prepare to adapt to its consequences. The BIC Scenarios were produced by the Met Office Hadley Centre.

Click here to read the press release.

Overview of Climate Change

Global climate is changing, and it is likely that most of the change seen over the last 50 years is due to emissions of greenhouse gases from human activity, such as carbon dioxide from the burning of fossil fuels. Emissions in the future are projected to increase, changing climate still further. Not only will temperatures rise, but there will be changes in patterns of precipitation (rain and snow) which will be both positive and negative, depending on location and season, and in many other quantities such as cloud and soil moisture.

Further Information

Intergovernmental Panel on Climate Change

Hadley Centre for Climate Prediction and Research

Why do we need Scenarios?

These changes have the potential to affect many areas of society, through their impact on agriculture, natural ecosystems, water resources, flooding, health, infrastructure, etc. The UN Framework Convention on Climate Change was agreed in 1992, with the aim of protecting the earth's climate, and subsequent negotiations resulted in the Kyoto Protocol, wherein developed countries agreed to mitigate the problem by reducing their greenhouse gas emissions. Although this will act to slow down climate change, its effect will initially be quite small, and it is becoming increasingly clear that we will also have to adapt to change. To do this, we require scenarios of future climate; these are plausible, self-consistent, states of climate for future periods. Climate change scenarios are the changes between current, or recent, climate and a scenario of future climate. Using climate change scenarios, adaptation can be planned well in advance, so that damages and costs can be minimised, and perhaps some potential benefits realised.

In April 2002, the UK Climate Impacts Programme published scenarios of climate change over the UK. However, even at the 50km resolution of the UKCIP02 scenarios, some of the major islands around the coast of the UK and Ireland could not be represented because they are smaller than this resolution, and hence their climate change could not be simulated. The UK government offered to prepare, on behalf of BIC, climate change scenarios that included the BIC island administrations. The Met Office Hadley Centre developed and ran a new regional climate model at 25km to predict changes over the Channel Isles, the Isle of Man, the Western Isles, the Orkney Islands and the Shetland Isles. Island climate change data from these model experiments are available from this website, and further details are available in the report "Scenarios of climate change for islands within the BIC region" (pdf version downloadable from this website), or email your BIC contact point (details below) to obtain a hard copy.

BIC contacts

States of Jersey
States of Guernsey
National Assembly for Wales
Defra, England
Department of the Environment, Heritage and Local Government, Ireland
Isle of Man Government
Department of the Environment, Northern Ireland
Scottish Executive

Summary of BIC Scenarios Results

• Global average temperatures have risen by about 0.7ºC over the last 100 years. It is likely that the rise over the past 50 years is mainly caused by fossil fuel burning.

• Temperatures on Jersey, Guernsey and the Isle of Man have also risen, particularly over the past few decades

• Global climate models predict a rise in global annual average temperatures, between 1990 and 2100, of 1.5 to 5.8ºC, taking into account both the range of future emissions projections developed by IPCC and a range of different climate models

• This report focusses on how climate change could affect islands within the BIC region. Following on from the UKCIP02 climate change scenarios, which do not have sufficient resolution to show the BIC islands, a version of the Hadley Centre regional climate model has been developed at a resolution of 25km which can resolve the Channel Islands, Isle of Man, Western Isles, Orkney Islands and Shetland Isles.

• Changes in summer and winter average temperature and precipitation between a recent climate (1961-1990), and the 2080s (2071-2100), for a Medium-High scenario of future emissions, are shown below. Warming is greatest in the south and less in the north and west; greater in summer and less in winter; ranging from 3.8ºC in the Channel Islands in summer to 1.4ºC in the Western Isles in winter. Annual mean change in precipitation is small for all the islands, but this is made up of large increases in winter and decreases in summer, and larger changes in the south than in the north. Changes are greatest in the Channel Islands, ranging from -45% in summer to +24% in winter. Snow is predicted to decrease by 70% over the Isle of Man to almost 100% in the Channel Isles. Mean winter wind speeds are predicted to increase by 8-10% for the Channel Islands, but confidence in this is very low. Changes in other quantities, and for other time periods and emissions scenarios, are given in the report.

• The values shown above all stem from the Hadley Centre climate models, with a Medium-High Emissions scenario. It is not possible to show results from a range of regional climate models, because there are no others which resolve the BIC islands. However, in the report we make the best estimate we can of the range of model uncertainty by using results from global models. Changes under other future emissions scenarios are estimated by scaling the Medium-High climate model predictions.

• The frequency of hot summer days in the Channel Isles and Isle of Man is expected to increase 4 to 5 fold by the 2080s under Medium-High Emissions scenario, with a 70-85% reduction in frosts. Days of heavy precipitation are expected to increase by 30-50% in winter, but decrease 40-50% in summer.

• Sea level is expected to increase by between 9cm and 69cm by the 2080s; this range takes into account uncertainties due to future emissions and due to modelling. When the effect of land movement is added, the net rise varies from 14-74cm in the Channel Islands to 9-69cm in Orkney Islands and Shetland Isles. With a sea level rise of 30cm, the change in height of the 50-year storm surge is predicted to be small for the Isle of Man and up to 0.5 metres higher for the Channel Islands.

• The North Atlantic ocean circulation, which includes the Gulf Stream, is predicted to decrease in strength by about 20% over the next 100 years, but not to switch off. Predictions above take account of reduced heating due to these Gulf Stream changes.

• The report also provides summary information about changes in climate over Ireland, based on the previously published UKCIP02 report; a recently published report from the Environmental Protection Agency in Ireland covers these in more detail.

• Although these scenarios show changes over the BIC islands for the first time, and are therefore a clear step forward, many uncertainties are attached to them. For decisions involving large investments it is recommended that these uncertainties are explored in more detail.