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 be between 2.5 and 4.7 degrees Celsius higher by 2100 compared with pre-industrial levels. In 2010, the Royal Society produced a summary report of current scientific evidence in 2010, which concluded that there is strong evidence that the warming of the earth over the last half century has been caused largely by human activity. 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 Celsius during this time.
Impacts on wildlife
The impact on wildlife of these changes may be profound. Even if changes happen at the lower end of the predicted range there will be losses (but also some gains) for habitats and species. However, if temperature changes surpass the higher end then we enter a whole new situation with potentially catastrophic impacts on ecosystems.
The IPCC has 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".
The England Biodiversity Strategy 2020, published in 2011, recognises that although, to date, climate change has had a relatively small impact on habitats and ecosystems that further climate change is unavoidable and impacts will become more significant. The strategy goes on to say that the effects of climate change on biodiversity are uncertain and may occur as sudden and unexpected step changes.
However, we do know that in the longer term, over a fifth (22%) of priority habitats are at high risk of direct impacts, including montane habitats, grazing marsh, saltmarsh and lakes. Many of these habitats are found in Norfolk. In addition, marine ecosystems are likely to be particularly seriously affected, particulalry as a result of ocean acidification due to rising CO2 levels”.
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 rises, 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.
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 reported in 2006 and 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. 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.
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. Although progress on the international scene has been disappointing, efforts are continuing to agree binding targets for control of emissions in order to ameliorate future climate change and hence impacts on biodiversity.
We believe that local action needs to take place alongside national and international action and we must both learn to adapt locally 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. NWT Living Landscape Initiative aims to make a strong contribution to this aim.
- 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.