New Model Sheds Light on Mosquito Spread in a Changing Climate

A new study, published online in the British Ecological Society journal, Functional Ecology, uses an innovative model to predict the spread of human disease vectors in a changing climate. Warren Porter, at the University of Wisconsin-Madison, has developed a unique model, 'NicheMapper', which allows researchers to answer the question: "Where would a species with a particular set of properties best survive and function on the planet?" Uniquely, the model also allows an organisms potential for evolutionary change to be incorporated, allowing the researchers to examine a range of scenarios.

The study focused on the dengue fever vector, the mosquito Aedes aegypti, and on its distribution and abundance in Australia. At present, the mosquito is confined to areas around Queensland, however, by modelling the insect's life history traits, capacity to evolve and climate change scenarios, the researchers conclude that a warming climate will allow the mosquito to expand its range into several populated areas of the continent, over the next 40-years. These conclusions are also likely to apply to populations of the mosquito found elsewhere in the world.

The researchers found that onefactor limiting the ability of the mosquito to spread would be the availability of standing water in which to lay its eggs. Simple measures, such as covering pools and water tanks, could have a large effect in reducing the spread of the insect. However, NicheMapper also allowed the researchers to model the effects on the species' distribution if the mosquito evolved to develop eggs tolerant of dessication; observed in other closely related species. In this case, combined with climate change, the mosquito could spread far, and rapidly.

Warren Porter claims that NicheMapper can be used to model the spread of almost any species on the planet; for example mapping the likely pattern of spread of invasive species. He has developed a company, 'Animaps' to make the software available to the scientific and policy communities.

Better Habitat Networks in Europe Will Benefit People and Wildlife

Conservationists and policy makers are conscious that many species ranges' may shift because of climate change, in fact many species have already begun to do so, (although this wasn't detected convincingly in the recent Countryside Survey Report for the UK).

Recent research published in the British Ecological Society's Journal of Applied Ecology investigated the extent to which the Natura 2000 network is capable of supporting European species in the face of climate change.

The investigators analysed how well connected forest, wetland and grassland ecosystems are across NW Europe now, and how they might become as a result of climate change. They also looked at the extent to which habitat networks will be able to facilitate species' movement under a specific climate change model.

The findings suggest that protected areas currently suitable for many species, will no longer be able to support these species in the future. The available habitat for different species in the future will vary, for example available habitat for the black woodpecker Dryocopus martius, marsh warbler Acrocephalus palustris and meadow pipit Anthus pratensis is expected to be around 70%, whereas the agile frog Rana dalmatina and bittern Botaurus stellaris only 6-8%. Considerable range shifts were also predicted, for example the middle spotted woodpecker Dendrocopus medius is anticipated to become more abundant in Ireland, the Netherlands and Denmark, as habitat becomes less suitable in France.

The authors emphasise the need to strengthen connectivity between ecosystem networks on a large spatial scale. Given the uncertainty surrounding the frequency of extreme weather events, how representative the study species are and the impact of curbing emissions on climate change, the precautionary principle should be applied.

Thus European policy should aim to broadly meet the needs of as many species as possible by increasing connectivity, whilst considering ecosystem services such as water regulation and carbon fixation. For example increasing wetlands across Europe will offer ecosystem services in terms of winter flood and summer drought alleviation, whilst providing increased connectivity for wetland species such as the bittern.

The research highlights the need to consider wildlife conservation in the context of future climate and habitat change. Presently BRANCH (Biodiversity Requires Adaptation in North Western Europe under a Changing Climate) are helping to fill the policy gaps, by pushing for the integration of planning with biodiversity needs.

The journal article is available for purchase from Wiley Interscience.

Read more about Natura 2000 here.

Source: Vos, C.C., Berry, P., Opdam, P. Baveco, H., Nijhof, B., O'Hanley, J., Bell, C., and Kuipers, H. (2008). Adapting landscapes to climate change: examples of climate-proof ecosystem networks and priority adaption zones. Journal of Applied Ecology. 45: 1722-1731.

Increase In Tropical Rainfall May Be Greater Than Predicted

Research published this week in Science suggests that an increase in tropical rainfall events, due to climate change, could be greater than predicted by models to date.

A team of researchers from the UK and the US analysed satellite data from 1988 - 2004, to assess how changes in temperature and atmospheric moisture affect the rainfall in the tropics. They found that the frequency of heavy rain is strongly associated with increasing temperature - in agreement with current climate models - but that these incidences are set to increase with temperature at a faster rate than so far predicted.

The researchers suggest that previous climate models, operating at a lower resolution, may miss localised heavy rainfall events, picked up by this model. They also suggest that future models should build in projections of how the atmosphere is going to respond to warming: as the atmospheric circulation alters, this will shift the distribution of rainfall events around the globe.

Allen R.P., Soden B.J. Atmospheric Warming and the Amplification of Precipitation Extremes. Science DOI: 10.1126/science.1160787

BES Facilitates 'Knowledge Transfer' Between Science and Policy

The BES, together with Defra, Natural England, the Countryside Council for Wales and the Woodland Trust, today held a workshop in Reading to explore the use of models, experiments and other techniques in assessing the possible future impacts of climate change on biodiversity and ecosystem services. Participants were drawn from both science and policy. The morning began with an exploration of the policy context surrounding biodiversity conservation in the UK, followed by a presentation on the science to policy relationship. One key point here was the need to understand that policy does not proceed in a linear way but that multiple factors, aside from scientific evidence, including anecdote and lobbying activities, public perception and the media, all act to influence how policy is produced.

A series of scientific presentations then explored means to project the direct and indirect impacts on climate change. It was clear from the presentation on the 'indirect impacts' that models linking socioeconomic factors to changes in biodiversity need further development. Finally, participants received a presentation from Alex Harvey, UK Climate Impacts Programme, on the forthcoming UKCIP08 scenarios, expected in November this year. UKCIP08 should provide a broader range of emissions scenarios for use by the community, along with a greater consideration of socioeconomic factors.

The main themes to emerge from the afternoon session, break-out groups to consider the morning's issues in more depth, were: the need for greater integration across Europe of the biodiversity monitoring activities already being taken; the need for investment in gathering greater basic data about individual species, their interactions and how this effects ecosystem response to climate change; and the need for greater knowledge transfer between scientists and policy-makers, in both directions. One specific issue highlighted was the limited funding available to allow methodologies developed to study the responses of a small number of species to climate change or other environmental factors, to be 'rolled out' and applied more widely across species.

To close the day there was a commitment from Defra to review the day's findings and use these in developing the Department's research programmes. The information would also be fed into other research funders, including into the Living With Environmental Change initiative, and into the devolved administrations. The BES looks forward to continuing to work with Defra and others to facilitate knowledge exchange between science and policy as this develops.

The full report of the workshop will be produced in due course and will be published on the BES's website.

Parliamentary Links Day: Science in an Uncertain World

Yesterday, the BES policy team attended the Parliamentary Links Day today at Portcullis House, Westminster, hosted by the Royal Society for Chemistry.

Politicians and leading scientists gave talks throughout the day, followed by the opportunity to interact with them afterwards at the reception.

Speakers included Dr Brian Iddon CChem FRSC MP Member Commons Select Committee on Innovation, Universities, Science and Skills; Rt Hon John Denham MP, Secratary State for Innovation, Universities and Skills, former and present chief scientific Advisors Professor Sir David King and Dr Bob Crawford, and Professor Rosemary Hails of the Institute of Biology and CEH. Numerous politicians and representatives from NGOs were amongst the audience too, including Rt. Hon Tony Benn and Rt. Hon Kenneth Clarke.

Research and Development

John Denham, Secretary of State for Innovation, Universities and Skills, led the proceedings citing a doubling in the research budget in the last two years and the UK's leadership in scientific output - second only to the USA. Mr Denham ranked the energy programme as the chief scientific priority for the UK with Aging research and security coming second and third. The Living With Environmental Change programme was mentioned, being particularly topical since food supply, energy security and terrorism present challenging and uncertain prospects.

Climate Change

Sir David King put forward a compelling and urgent case for the reduction of carbon emissions globally, in light of a projected 2-3 degrees centigrade rise in global temperatures. Historically, some important global and local environmental issues have been identified by scientists, leading to policy change resulting in positive outcomes. These include London smog, addressed by the banning of coal fires in 1963, and global ban on CFC use in refrigerators and aerosols resulting in 'rebuilding' of the ozone layer. In this sense, Sir David King believes that, with global ratification of binding reduction in greenhouse gas emissions, through 'decarbonisation' of the global economy, the negative consequences of climate change can be abated.

Questions led by the British Psychological Society prompted Sir David to reiterate the need for government cabinets to really take on board the idea of decarbonising the economy. The need for a frameshift in national psychology, in that as a society we must stop idolising celebrity over-consumption, is imperative.

Ecosystems Approach

Professor Rosie Hails focused on the need for an ecosystems-based approach to valuing biodiversity in future development proposals, given society's dependence on nature's goods and services for food, materials and environmental regulation. This approach is also in accordance with the guidelines of the Millenium Ecosystem Assessment and the UNEP-Global Outlook-4 ProfessorHails called for an end to the extensive bureaucracy associated with GM crops applications on the basis of scientifically unvalidated safety and environmental concerns. Particular emphasis was made on the need for regulation that is proportional to benefits and risks, rather than sentiment.

Overall, the day presented the opportunity to both meet high profile scientists and key politicians as well as ascertain the hot scientific topics scientists are hoping politicians and policy-makers will act upon.

Soil Biodiversity Integral to Carbon Cycling

The respiration of soil is a key function in the carbon cycle, moving carbon from the ground to the atmosphere.

Peatland across Northern Europe occupies somewhere in the region of 3.5 million km2 and holds one third of the world's soil carbon. These areas are under pressure from increased agricultural activity, which accelerates the net loss of carbon dioxide. Theory and practice suggests that afforestation will result in net carbon uptake and reduce carbon loss to the atmosphere from soil respiration. Although soils are thought to act as a sink for carbon, land-use change such as agriculture alters the way that carbon dioxide is emitted.

Currently tree plantations are believed to be a worthwhile mitigation technique against climate change. However, in a research paper published in Soil Biology and Biochemistry, researchers found that previous agriculture on afforested land led to higher soil respiration than undisturbed areas, up to decades after afforestation.

At present, European legislation is placing an emphasis on the role of afforestation in combating climate change. This research suggests that further work is required into the effects of climate change on soil biodiversity and the subsequent effect on the carbon cycle.

BES members and readers of the blog are invited to discuss this article.

Modelling the Health Impacts of Climate Change

A new report suggests that more needs to be done to adapt systems models to adequately reflect the dangers posed to human health by climate change.

Most research on the impacts of climate change has focused on the environmental consequences, rather than the health impacts. The Intergovernmental Panel on Climate Change (IPCC) predict that it is very likely that climate change will increase threats to human health. Direct impacts are posed by an increase in the incidence of extreme temperature and weather events, whilst indirect effects could be the increase in infectious disease, for example malaria, caused by warmer temperatures and changes in the hydrologic cycle.

Modelling the health impacts of, for example, malaria, and how this may change under climate change scenarios, is complex, due to the range of factors which can affect the geographic range of the vector, such as drug resistance and economic development. The report suggests that new models should better account for these drivers and develop country-specific projections of risk.

The priorities of healthcare funders are identified as one of the key factors limiting development of these models. To date, healthcare funders have had little interest in developing interdisciplinary models - for example modelling the interaction between land-use and climate change on human health.