We review the literature regarding the aggregation of benefit value estimates for non-market goods. Two case studies are presented through which we develop an approach to aggregation which applies the spatial analytic capabilities of a geographical information system to combine geo-referenced physical, census and survey data to estimate a spatially sensitive valuation function. These case studies show that the common reliance upon political jurisdictions and the use of sample mean values within the aggregation process are liable to lead to significant errors in resultant values. We also highlight the fact that for resources with use values then we should expect overall values to reduce with increasing distance from such sites, but that changes in the choice of welfare measure will determine whether such 'distance decay' is to be expected within values stated by those who are presently non-users. The paper concludes by providing recommendations for future improvements to the methodology.

Extractive activities targeting a wide range of nontimber forest products ( NTFPs ) are ubiquitous in tropical forests, yet the extent of structurally intact forests in a given region affected by this form of cryptic disturbance is poorly documented. We conducted a basin‐wide geographic information system analysis of the nonmotorized accessibility of Amazonian NTFP extraction and estimated the proportion of the Amazon drainage basin within Brazil ( 3.74 million km 2 ) that can be accessed on foot from the nearest navigable river or functional road. We use a long‐term series of standardized line‐transect vertebrate censuses conducted throughout the region to illustrate the effects of physical accessibility on wildlife densities in terms of hunting pressure as a function of distance from the nearest point of access. Population abundance in large‐bodied, prime‐target species preferred by game hunters tended to increase at greater distances from the access matrix, whereas small‐bodied species ignored by hunters usually showed the reverse trend. In addition, we estimated the proportion of presumably inviolate core areas within nature, extractive, and indigenous reserves of Brazilian Amazonia that are prohibitively remote and unlikely to be overhunted; for instance, only 1.16% of the basin‐wide area is strictly protected on paper and is reasonably safe from extractive activities targeted to game vertebrates and other valuable NTFPs. Finally, we discuss the concept of truly undisturbed wildlands in the last major tropical forest regions by distinguishing potentially overharvested areas from those that remain largely or entirely pristine and that maintain viable populations of a full complement of harvest‐sensitive species.

Background:Globally, pollen allergy is a major public health problem, but a fundamental unknown is the likely impact of climate change. To our knowledge, this is the first study to quantify the consequences of climate change upon pollen allergy in humans.Objectives:We produced quantitative estimates of the potential impact of climate change upon pollen allergy in humans, focusing upon common ragweed (Ambrosia artemisiifolia) in Europe.Methods:A process-based model estimated the change in ragweed’s range under climate change. A second model simulated current and future ragweed pollen levels. These findings were translated into health burdens using a dose–response curve generated from a systematic review and from current and future population data. Models considered two different suites of regional climate/pollen models, two greenhouse gas emissions scenarios [Representative Concentration Pathways (RCPs) 4.5 and 8.5], and three different plant invasion scenarios.Results:Our primary estimates indicated that sensitization to ragweed will more than double in Europe, from 33 to 77 million people, by 2041–2060. According to our projections, sensitization will increase in countries with an existing ragweed problem (e.g., Hungary, the Balkans), but the greatest proportional increases will occur where sensitization is uncommon (e.g., Germany, Poland, France). Higher pollen concentrations and a longer pollen season may also increase the severity of symptoms. Our model projections were driven predominantly by changes in climate (66%) but were also influenced by current trends in the spread of this invasive plant species. Assumptions about the rate at which ragweed spreads throughout Europe had a large influence upon the results.Conclusions:Our quantitative estimates indicate that ragweed pollen allergy will become a common health problem across Europe, expanding into areas where it is currently uncommon. Control of ragweed spread may be an important adaptation strategy in response to climate change.Citation:Lake IR, Jones NR, Agnew M, Goodess CM, Giorgi F, Hamaoui-Laguel L, Semenov MA, Solomon F, Storkey J, Vautard R, Epstein MM. 2017. Climate change and future pollen allergy in Europe. Environ Health Perspect 125:385–391; http://dx.doi.org/10.1289/EHP173

BackgroundThere is much uncertainty about the future impact of climate change on vector-borne diseases. Such uncertainty reflects the difficulties in modelling the complex interactions between disease, climatic and socioeconomic determinants. We used a comprehensive panel dataset from Mexico covering 23 years of province-specific dengue reports across nine climatic regions to estimate the impact of weather on dengue, accounting for the effects of non-climatic factors.Methods and FindingsUsing a Generalized Additive Model, we estimated statistically significant effects of weather and access to piped water on dengue. The effects of weather were highly nonlinear. Minimum temperature (Tmin) had almost no effect on dengue incidence below 5°C, but Tmin values above 18°C showed a rapidly increasing effect. Maximum temperature above 20°C also showed an increasing effect on dengue incidence with a peak around 32°C, after which the effect declined. There is also an increasing effect of precipitation as it rose to about 550 mm, beyond which such effect declines. Rising access to piped water was related to increasing dengue incidence. We used our model estimations to project the potential impact of climate change on dengue incidence under three emission scenarios by 2030, 2050, and 2080. An increase of up to 40% in dengue incidence by 2080 was estimated under climate change while holding the other driving factors constant.ConclusionsOur results indicate that weather significantly influences dengue incidence in Mexico and that such relationships are highly nonlinear. These findings highlight the importance of using flexible model specifications when analysing weather–health interactions. Climate change may contribute to an increase in dengue incidence. Rising access to piped water may aggravate dengue incidence if it leads to increased domestic water storage. Climate change may therefore influence the success or failure of future efforts against dengue.

Background: Anthropogenic climate change will affect global food production, with uncertain consequences for human health in developed countries.Objectives: We investigated the potential impact of climate change on food security (nutrition and food safety) and the implications for human health in developed countries.Methods: Expert input and structured literature searches were conducted and synthesized to produce overall assessments of the likely impacts of climate change on global food production and recommendations for future research and policy changes.Results: Increasing food prices may lower the nutritional quality of dietary intakes, exacerbate obesity, and amplify health inequalities. Altered conditions for food production may result in emerging pathogens, new crop and livestock species, and altered use of pesticides and veterinary medicines, and affect the main transfer mechanisms through which contaminants move from the environment into food. All these have implications for food safety and the nutritional content of food. Climate change mitigation may increase consumption of foods whose production reduces greenhouse gas emissions. Impacts may include reduced red meat consumption (with positive effects on saturated fat, but negative impacts on zinc and iron intake) and reduced winter fruit and vegetable consumption. Developed countries have complex structures in place that may be used to adapt to the food safety consequences of climate change, although their effectiveness will vary between countries, and the ability to respond to nutritional challenges is less certain.Conclusions: Climate change will have notable impacts upon nutrition and food safety in developed countries, but further research is necessary to accurately quantify these impacts. Uncertainty about future impacts, coupled with evidence that climate change may lead to more variable food quality, emphasizes the need to maintain and strengthen existing structures and policies to regulate food production, monitor food quality and safety, and respond to nutritional and safety issues that arise.