Climate Change

This page describes the impacts of climate change on wildlife in Norfolk, how this may impact on the work of Norfolk Wildlife Trust and what steps NWT needs to take to deal with this issue.

Climate Research Background

The UN Intergovernmental Panel on Climate Change (IPCC) believes that global average temperatures will rise by between 1.4 and 5.8 degrees Centigrade over the current century. The IPCC concluded recently that there is now strong evidence that most of the warming over the last 50 years is attributable to human activities. Whatever the cause, we will need to respond to the effects of climate change.

In the UK the Climate Impacts Programme has predicted the likely temperature rise in the UK over the next 80 years based on low to high emission scenarios for greenhouse gases. These scenarios correspond to temperature rises of between 2 and 4 degrees Centigrade during this time.

In February 2005 the UK government sponsored a major conference on Avoiding Dangerous Climate Change, where research evidence was presented from many scientific disciplines all pointing to the severe and potentially catastrophic impacts on ecosystems throughout the world unless urgent action is taken to control emissions of greenhouse gases.

Impacts on wildlife

The impact on wildlife of these changes may be profound. At a recent conference on Biodiversity and Climate Change at the University of East Anglia, experts agreed that if changes happen at the lower end of the predicted range there will be losses (but also some gains) for habitats and species but existing ecosystems are liable to be able to cope. However, if temperature changes surpass the higher end (which new forecasts are likely to predict) then we enter a whole new situation with potentially catastrophic impacts on ecosystems.

The IPCC recently concluded "the collective evidence indicates that there is a high confidence that recent regional changes in temperature have already had discernible impacts on many physical and biological systems". English Nature's position statement on climate change says that "there is clear evidence to show that plants and animals including those characteristic of the English countryside and our seas are being affected by climate change". Climate change is an important driving mechanism for altering the distribution of species and, therefore, the species composition of habitats.

Furthermore these changes will take place in fragmented landscapes (such as those found in East Anglia) where much of our wildlife is restricted to small, isolated habitats surrounded by an intensively farmed landscape. Even if our climate were to remain stable these species would have difficulty surviving in such conditions but with climate change their future survival is more problematical.

The MONARCH Project has attempted to predict the effects of climate change in detail on a selected number of species. One of the areas this project has focussed on is southeast England. The project looked at the predicted impact of both temperature and rainfall changes on species distribution. In south east England there is likely to be substantially less water available in summer period leading to desiccation of wetland habitats. As a result, wet heaths, coastal dune slacks drought-prone acid grassland and some chalk grassland species could be adversely affected by this lower water availability. Wet heaths may revert to dry heath leading to loss of species such as cross-leaved heath. Pools on dune slacks are likely to disappear earlier in the year, which may have an adverse impact on the rare natterjack toad. However, there is likely to be little impact on another important amphibian in Norfolk, the great crested newt.

Although birds can cope more easily with changing climate by shifting their distribution, changes elsewhere may still have impacts on migrating and wintering species. Numbers of snow buntings over-wintering on the Norfolk coast may decline if conditions become less severe further north. However, conditions in East Anglia are likely to become more suitable for a number of species such as yellow wagtail and nightingale (which is currently in a slight decline). In addition there has been a recent increase in southern species of dragonflies colonising this country and this process of northerly movement of mobile species is likely to continue.

Increases in sea level as a result of thermal expansion of the oceans will encourage erosion of saltmarsh, sand dune and other coastal habitats. As sea levels rise the high tide line moves higher up the beach resulting in coastal squeeze, whereby coastal habitats are squeezed against the shoreline. This results in reduced area of habitat and also threatens coastal defences that currently protect freshwater habitats. The impact of sea level rise is already being felt at Norfolk Wildlife Trust nature reserves at Cley and Holme.

Choices

The changes described above have already been set in motion as result of past increases in greenhouse gases. They are happening now and will happen whatever steps are taken to control present emissions. However, most climate scientists believe that there is an opportunity to limit impacts if the world takes steps to cut down on emissions of greenhouse gases. The targets currently being adopted by many European countries if adopted and achieved more widely could just fulfil this objective.

As a result we must both learn to adapt to anticipated climate change and take whatever steps we can to move towards reducing future greenhouse gas emissions.

What is Norfolk Wildlife Trust doing?

For NWT this means planning for changes that we know will occur, playing our part in reducing our impacts and educating and persuading others of the importance of meeting low greenhouse gas emission targets. We will:

• Manage our nature reserves to take account of climate change. Our conservation priorities may change as new species colonise sites. At Cley and Salthouse we already have to face up to this challenge.
• Actively encourage the reduction of habitat fragmentation and the large-scale creation of habitats to help wildlife to adapt to climate change. The creation of an ecological network is a key objective of the trust's corporate plan.
• Educate others concerning the impacts of climate change on wildlife and encourage others to take steps to reduce the scale of their impact.
• Advocate environmentally sustainable development policy measures and cultural changes to reduce long-term emissions of greenhouse gases. This may include supporting renewable energy and alternatives to car based transport systems.
• Ensure that the Trust's own activities result in a reduction in greenhouse gas emissions. The Trust is developing an environmental policy and action plan to help achieve this.