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This paper examines the impact of climate change on primary crops grown in Africa. An innovative approach is presented that bridges the gap between agro-economic and traditional Ricardian models. We label it a ‘structural Ricardian model’. It first captures the type of crop a farmer will select and then examines the conditional net revenue of that crop. The model is estimated using a sample of over 5000 farmers across 11 countries in Africa. The analysis finds that farmers shift the crops they plant to match the climate they face. Studies that fail to account for crop switching will overestimate the damages from climate change and underestimate the benefits.

On May 7, 2010, a letter signed by 255 members of the US National Academy of Sciences deplored attacks on both science and scientists who researched climate science or related fields. The assaults in the letter rely on two main components. First, statements contradict the preponderance of scientific evidence without a comparable body of evidence to the contrary. Second, as the size of the Intergovernmental Panel on Climate Change (IPCC) reports grows, so does the probability of minor errors. Scientists and their organization should not have to spend the majority of their time defending their work, instead of working on their primary mission of conducting scientific research.

The oleaginous yeast Lipomyces starkeyi is interesting for industrial-scale production of biodiesel. Here it is reported that this yeast is able to digest unsaccharified, soluble potato starch. In these experiments, the cultivation time of Lipomyces starkeyi was reduced to half of the previously reported values. The effect of C:N molar ratio was studied on growth and lipid content of L. starkeyi in media containing glucose or potato starch as C-source. At a C:N molar ratio of 61.2 in glucose medium, the lipid content was measured at 30 % of the dry matter. It was established that the cellular lipid content increased with increasing C:N molar ratio, but the cell yield decreased. In a pH-controlled 1-litre agitated and aerated bioreactor, batch cultivation on glucose resulted in 23 % lipids in cells on dry mass basis (dm), cell yield of 0.25 g/g glucose, and lipid yield of 0.06 g/g glucose. Under the same operating conditions, fed-batch cultivation with discrete glucose additions resulted in 27 % lipids, cell yield of 0.28 g/g glucose, and lipid yield of 0.08 g/g glucose. On soluble but unsaccharified sweet potato starch, cell yield was 0.41 g/g glucose equivalent, lipid yield 0.16 g/g glucose equivalent, and lipid content in cells 40 %. The major fatty acids in the cells were C16:0 and C18:1 (accounting for 85–90 % by mass of the total lipids) with the rest being C16:1 and C18:0. All of these are valuable lipids for biodiesel production. Based on these results, wastes and wastewater from food industry and sewage sludge could serve as sources for the production of biodiesel. Kvasac Lipomyces starkeyi je zanimljiv za industrijsku proizvodnju biodizela, a dokazano je da može preraditi topljivi škrob iz krumpira. Stoga je uzgojen u pokusu, i to za upola kraće vrijeme nego u usporedbi s prethodnim ispitivanjima. Na podlozi je s glukozom ili škrobom iz krumpira, kao izvorima ugljika, ispitan utjecaj molarnog omjera C:N na rast L. starkeyi i udio lipida u kvascu. Udio je lipida u podlozi s glukozom, pri omjeru n(C):n(N)=61,2, iznosio 30 % suhe tvari. Utvrđeno je da se povećanjem C:N omjera povećava udio lipida u stanici, a smanjuje prinos stanica. Šaržnim su uzgojem na glukozi u bioreaktoru s miješalicom i prozračivanjem, volumena 1 L, te uz kontrolu pH-vrijednosti, dobivene ove vrijednosti: udio lipida u stanici od 23 % (na bazi suhe tvari), prinos stanica od 0,25 g suhe tvari/g glukoze i prinos lipida od 0,06 g/g glukoze. U istim je uvjetima šaržnim uzgojem s pritokom glukoze u malim obrocima dobiveno 27 % lipida, te postignut prinos stanica od 0,28 g suhe tvari/g glukoze i prinos lipida od 0,08 g/g glukoze. Uzgojem na podlozi s topljivim škrobom iz slatkog krumpira dobiven je prinos stanica od 0,41 g suhe tvari/g ekvivalenta glukoze, prinos lipida od 0,16 g/g ekvivalenta glukoze, te udio lipida u stanicama od 40 %. U stanicama su prevladavale C16:0 i C18:1 masne kiseline (85-90 % mase ukupnih lipida), a ostatak su bile C16:1 i C18:0 masne kiseline. Svi se ti lipidi mogu koristiti za proizvodnju biodizela. Rezultati upućuju na to da su otpad i otpadne vode iz prehrambene industrije te kanalizacijski mulj dobre sirovine za proizvodnju biodizela.

This paper tries to identify under which conditions voluntary certification could be an answer to the governance of sustainability at global level. The study addresses the case of biofuel sustainability certification in Brazil and the role of the EU Directive on biofuels. The case study has permitted to identify and analyze some of these factors as the degree of dependence from foreign market, the policy environment, the structure of the supply chain, the benefits and costs associated to certification as well as some unintended consequences. The research has been conducted through a case study in the state of Sao Paolo (Brazil).

During the industrialization era in the U.S., most waterways in urban areas were buried underground. Daylighting, the process of resurfacing and restoring buried aquatic systems, has grown as a planning practice. This practice can bring to communities environmental, economic, and social benefits—making cities more sustainable and livable. City Creek in Salt Lake City will be used as a case study of a future daylighting project in Euclid, a minority and low income neighborhood. In particular, this paper will highlight planning and locally-driven efforts to raise awareness among residents on the importance of conserving and restoring stream ecosystems. The article will discuss what community members involved in a visioning process would like to see in the development of a much-needed recreational trail and why it matters that City Creek becomes a vital community asset. Ultimately, this paper seeks to empower communities to plan and implement daylighting projects at the local level. UPLanD - Journal of Urban Planning, Landscape & environmental Design, Vol 2, No 3: BLUE

Over the past two decades dam removal has emerged as a viable tool for ecological restoration of riverine landscapes, partially as a result of changing societal values toward the ecological trade-offs associated with dammed rivers. Dam condition, purpose and ownership are key factors that determine the legal and political processes that lead to dam removal in most cases. In the United States removals of small, privately owned dams are most common, although the most high-profile removals are associated with large hydropower dams subject to a federal relicensing process. Scholars cite this legal process for periodic re-evaluation of hydroelectric dams as an important window of opportunity for institutionalising adaptive environmental governance toward the renegotiation of social and ecological values associated with rivers. It is clear, however, that this policy process alone is not sufficient to facilitate large-scale dam removal and larger transitions toward adaptive governance. In this paper we review several high-profile cases of dam relicensing and removal in the Pacific Northwest region of the US to better understand the combination of factors that couple with dam relicensing policy to present a window of opportunity for adaptive governance and social-ecological restoration. Examples from the Pacific Northwest reveal patterns suggesting the critical role of endangered species, Native American tribes, local politics and economics in determining the future of large hydropower dams in the United States.

Using a combination of dynamical and statistical downscaling techniques, we projected mid-21stcentury warming in the Los Angeles region at 2-km (1.2-mile) resolution. To account for uncertainty associated with the trajectory of future greenhouse gas emissions and other factors affecting the planet's energy balance, we examined projections for both "business-as-usual" (RCP8.5) and "mitigation" (RCP2.6) emissions scenarios of the Fifth Coupled Model Intercomparison Project. To account for the considerable uncertainty associated with choice of global climate model, we downscaled results for all available global models. For the business-as-usual scenario, we find that by the mid-21stcentury, the most likely warming is roughly 4.6°F averaged over the region's land areas, with a 95% confidence that the warming lies between 1.7 and 7.5°F. The high resolution of the projections reveals a pronounced spatial pattern in the warming: High elevations and inland areas separated from the coast by at least one mountain complex warm 20 to 50% more than the areas near the coast or within the Los Angeles basin. This warming pattern is especially apparent in summertime. The summertime warming contrast between the inland and coastal zones has a large effect on the most likely expected number of extremely hot days per year. Coastal locations and areas within the Los Angeles basin see roughly two to three times the number of extremely hot days, while high elevations and inland areas typically experience approximately three to five times the number of extremely hot days. Under the mitigation emissions scenario, the most likely warming and increase in heat extremes are somewhat smaller. However, the majority of the warming seen in the business-as-usual scenario still occurs at all locations in the most likely case under the mitigation scenario, and heat extremes still increase significantly. Therefore adaptation to a changing climate over the next few decades is likely to be inevitable in the Los Angeles region.

The developers of the Paharpur Business Center (PBC) and Software Technology Incubator Park in New Delhi, India offer an environmentally sustainable building with a strong emphasis on energy conservation, waste minimization and superior indoor air quality (IAQ). To achieve the IAQ goal, the building utilizes a series of air cleaning technologies for treating the air entering the building. These technologies include an initial water wash followed by ultraviolet light treatment and biolfiltration using a greenhouse located on the roof and numerous plants distributed throughout the building. Even with the extensive treatment of makeup air and room air in the PBC, a recent study found that the concentrations of common volatile organic compounds and aldehydes appear to rise incrementally as the air passes through the building from the supply to the exhaust. This finding highlights the need to consider the minimization of chemical sources in buildings in combination with the use of advanced air cleaning technologies when seeking to achieve superior IAQ. The goal of this project was to identify potential source materials for indoor chemicals in the PBC. Samples of building materials, including wood paneling (polished and unpolished), drywall, and plastic from a hydroponic drum that was part of the air cleaning system, were collected from the building for testing. All materials were collected from the PBC building and shipped to the Lawrence Berkeley National Laboratory (LBNL) for testing. The materials were pre-conditioned for two different time periods before measuring material and chemical specific emission factors for a range of VOCs and Aldehydes. Of the six materials tested, we found that the highest emitter of formaldehyde was new plywood paneling. Although polish and paint contribute to some VOC emissions, the main influence of the polish was in altering the capacity of the surface to accumulate formaldehyde. Neither the new nor aged polish contributed significantly to formaldehyde emissions. The VOC emission stream (excluding formaldehyde) was composed of up to 18 different chemicals and the total VOC emissions ranged in magnitude from 7 mu g/m2/h (old wood with old polish) to >500 mu g/m2/h (painted drywall). The formaldehyde emissions from drywall and old wood with either new or old polish were ~;;15 mu g/m2/h while the new wood material emitted >100 mu g/m2/h. However, when the projected surface area of each material in the building was considered, the new wood, old wood and painted drywall material all contributed substantially to the indoor formaldehyde loading while the coatings contributed primarily to the VOCs.