Assessing Impacts of Climatic Change in Marginal Areas: The Search for an Appropriate Methodology

With the support of the UN Environmental Programme a major 2-year project is currently being initiated to investigate the impacts of short-term climatic variations and the likely long-term effects of CO2-induced climatic changes on agricultural output at the sensitive margins of food grains and livestock production. This paper sets the stage for the above-mentioned project. It reviews the notion of climate-related marginality, and proposes to measure the impact of climatic fluctuations on marginal areas by a temporal change in the level of risk of harvest failure and spatial shifts of crop pay-off boundaries. The practical usefulness of these measures is illustrated by several case examples from the US, Canada, and Northern Europe. Finally, the paper outlines the crop/climate simulation model, successfully applied for analysis of the effects of possible climatic changes on cereal yields in Northern England. Over the next two years it will be the aim of the IIASA project to further develop this methodology and to evaluate the impact on food production of possible changes in climate

Assessing the Impact of Climatic Change in Cold Regions

In September 1983 IIASA, together with the Austrian Government, the World Resources Institute and UNESCO, supported an International Study Conference on the Sensitivity of Ecosystems and Society to Climatic Change, which was cosponsored by the World Meteorological Organization, UNEP, and the International Council of Scientific Unions. The purpose of this meeting, which was attended by scientists from 17 countries, was to evaluate the impact of climatic fluctuations on the sensitive margins of agriculture and of natural terrestrial ecosystems. The emphasis was on climatic change that might result from increases in the amount of carbon dioxide in the atmosphere, but consideration was also given to past climatic fluctuations, both short- and long-term. This report is a summary of deliberations by participants in the workshop, of the observations that emerged, and of the recommendations made

Policy-Oriented Impact Assessment of Climatic Variations

IIASA organized a Task Force Meeting (held in late June 1986) to undertake a policy-oriented assessment of various climatic impacts. Among the questions addressed were: What are the main policy questions and research needs of this field? Is there a niche for IIASA to fill meaningfully over the next several years? If so, should the work be an independent entity within the current Environment Program or should it be absorbed within the framework of other projects? This report of the Task Force Meeting provides a focus not only for IIASA, but also for many other national and international bodies engaged in climate impact research. In particular, the idea of integrated regional assessments seems to have caught on, and this Research Report is likely to become a basic reference

The Effect of Climatic Variations on Agricultural Risk

The thesis of this paper is that impacts from climatic change can be evaluated effectively as changes in the frequency of short-term, anomalous climatic events. These can then be expressed as changes in the level of risk of impact from climatic extremes. To evaluate this approach, the risk of crop failure resulting from low levels of accumulated temperature is assessed for oats farming in southern Scotland. Annual accumulated temperatures are calculated for the 323-year long temperature record compiled by Manley for Central England. These are bridged across to southern Scotland and, by calculating mean levels of risk for different elevations, an average "risk surface" is constructed. 1-in-10 and 1-in-50 frequencies of crop failure are assumed to delineate a high-risk zone, which is mapped for the 323-year period by constructing isopleths of these risk levels. By re-drawing the risk isopleths for warm and cool 50-year periods, the geographical shift of the high-risk zone is delineated. The conclusion is that relatively recent and apparently minor climatic variations in the United Kingdom have in fact induced substantial spatial changes in levels of agricultural risk. An advantage of expressing climatic change as a change in agricultural risk, is that support programs for agriculture can be re-tuned to accommodate acceptable frequencies of impact by adjusting support levels to match new risk levels

Climate Change and World Agriculture

In 1990 the Intergovernmental Panel on Climate Change (IPCC) completed its report on the greenhouse effect. The IPCC had been set up under the auspices of the World Meteorological Organisation and the United Nations Environment Programme, to examine how climate and sea level might change, what might be the impact of these changes and what could be the most appropriate response to them. IPCC Working Groups tackled each of these three tasks. Working Group II (Impacts) concluded that greenhouse gas-induced changes of climate would have an important effect on agriculture, with the most severe negative impacts probably occurring in regions of high present-day vulnerability that are least able to adjust technologically to such effects. 1 The purpose of this book is to consider, in more detail than could be covered within the confines of the IPCC report on agriculture, the reasoning behind this conclusion, its implications for global food security and the most appropriate courses of action

The Sensitivity of Natural Ecosystems and Agriculture to Climatic Change

In September 1983, IIASA and UNEP, together with the Austrian Government, gave support to an International Study Conference on The Sensitivity of Ecosystems and Society to Climatic Change, which was attended by scientists from 17 countries. The conference was divided into two parallel workshops - on climate impacts in cold and in semiarid regions. This report brings together eight papers that ultimately arose from discussions in the "cold" workshop. In most cases they report the results of preliminary experiments relating to climatic change, and represent the outcome of a piece of "pilot" research by IIASA for UNEP to test the research methodology before applying it in a wider context. Of the variety of techniques and concepts applied, two deserve mention here. The first is the mapping of impact areas by the spatial shift of isopleths or boundaries. The second is the construction of a hierarchy of climate, impact, and economic models to trace the cascade of climate impacts through biophysical, economic, and social systems. This report marks the completion of IIASA's pilot study. The full research project, funded jointly by UNEP and IIASA, is now being implemented in 12 case studies through a collaborative network of 70 scientists. Its purpose is to evaluate the impact of climatic change and variability on food production in climate-sensitive areas, and to consider appropriate policies of mitigation

Climate Impact Analysis in Cold Regions

Among the many factors influencing agricultural and forest productivity worldwide, the effects of weather and climate are of considerable importance. Anomalous fluctuations of climate, particularly thermal conditions, can have a marked effect in high latitude regions where activities are already constrained by low temperatures and a short growing season. Moreover, a consideration of possible future climatic changes (e.g. those that may result from increased concentrations of atmospheric carbon dioxide) adds a further dimension to the problem of assessing the regional sensitivity of crop production to climate. In many regions, the impacts of a climatic event extend well beyond the direct, physical response of crops. For instance, the resulting changes in crop production may affect farm incomes, regional food-based industries, employment and prices, with the ripple-effects filtering through to other sectors of an economy and society. This paper outlines a methodology for assessing the sensitivity of crop productivity to climate and shows how this may be elaborated to include a consideration of the economic and social implications of crop productivity changes. The approach uses a hierarchy of models, each one representing a stage in the cascade of responses induced by an anomalous climatic event. In particular, three sets of models are identified - of climatic changes, of climate impacts on potential and actual yield, and of the down-stream economic and social effects of these. By considering a range of credible future climatic scenarios, it is possible to produce estimates of impact and to examine a range of adjustments that might be of interest to the agricultural planner or decision-maker. The methodology is being tested in ten countries as part of a two year IIASA/UNEP research project

Climate Change and World Food Security: A New Assessment

Building on previous work, quantitative estimates of climate change impacts on global food production have been made for the UK Hadley Centre's HadCM2 greenhouse gas only ensemble experiment and the more recent HadCM3 experiment (Hume et al., 1999). The consequences for world food prices and the number of people at risk of hunger as defined by the Food and Agriculture Organization (FAO, 1998) have also been assessed. Climate change is expected to increase yields at high and mid-latitudes, and lead to decreases at lower latitudes. This pattern becomes more pronounced as time progresses. The food system may be expected to accommodate such regional variations at the global level, with production, prices and the risk of hunger being relatively unaffected by the additional stress of climate change. By the 2080s the additional number of people at risk of hunger due to climate change is about 80 million (+/- 10 million depending on which of the four HadCM2 ensemble members are selected). However, some regions (particularly the arid and sub-humid tropics) will be adversely affected. A particular example is Africa, which is expected to experience marked reduction in yield, decreases in production, and increases in the risk of hunger as a result of climate change. The continent can expect to have between 55 and 65 million extra people at risk of hunger by the 2080s under the HadCM2 climate scenario. Under the HadCM3 climate scenario, the effect is even more severe, producing an estimated additional 70+ million people at risk of hunger in Africa

Travel, tourism, climate change and behavioral change: travelers’ perspectives from a developing country, Nigeria

While studies have examined people's understanding of climate change and its relationship to tourism, these focus largely on developed country populations. Much future tourism growth will come from developing countries following economic development; often countries where climate change will be strongly felt. Do tourists from developing countries have the same knowledge gaps about travel, tourism, and climate change as in the developed world? Will behavioral change policies be successful in encouraging more environmentally friendly approaches to climate change and tourism in developing countries? This paper presents findings from 20 in-depth interviews with active Nigerian tourists, analyzing their understanding of climate change, the links known, or not, between their travel and climate change, and their willingness to change their tourism patterns. Understanding of climate change was limited and there was conceptual confusion. Participants did not view their own travel as a cause of climate change and many were embedded in air travel practice. Participants were unwilling to change their tourism patterns to reduce their contribution to climate change. Significant structural barriers limit low carbon tourism travel in Nigeria (and other developing countries), including reliability, availability safety, and speed. Behavioral change will be difficult to achieve

Can forest management based on natural disturbances maintain ecological resilience?

Given the increasingly global stresses on forests, many ecologists argue that managers must maintain ecological resilience: the capacity of ecosystems to absorb disturbances without undergoing fundamental change. In this review we ask: Can the emerging paradigm of natural-disturbance-based management (NDBM) maintain ecological resilience in managed forests? Applying resilience theory requires careful articulation of the ecosystem state under consideration, the disturbances and stresses that affect the persistence of possible alternative states, and the spatial and temporal scales of management relevance. Implementing NDBM while maintaining resilience means recognizing that (i) biodiversity is important for long-term ecosystem persistence, (ii) natural disturbances play a critical role as a generator of structural and compositional heterogeneity at multiple scales, and (iii) traditional management tends to produce forests more homogeneous than those disturbed naturally and increases the likelihood of unexpected catastrophic change by constraining variation of key environmental processes. NDBM may maintain resilience if silvicultural strategies retain the structures and processes that perpetuate desired states while reducing those that enhance resilience of undesirable states. Such strategies require an understanding of harvesting impacts on slow ecosystem processes, such as seed-bank or nutrient dynamics, which in the long term can lead to ecological surprises by altering the forest's capacity to reorganize after disturbance