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The United States and others should consider adopting a different approach to estimating costs and benefits in light of uncertainty. In economic project analysis, the rate at which future benefits and costs are discounted relative to current values often determines whether a project passes the benefit-cost test. This is especially true of projects with long time horizons, such as those to reduce greenhouse gas (GHG) emissions. Whether the benefits of climate policies, which can last for centuries, outweigh the costs, many of which are borne today, is especially sensitive to the rate at which future benefits are discounted. This is also true of other policies, e.g., affecting nuclear waste disposal or the construction of long-lived infrastructure.

Bismuth thin films have been deposited using pulsed DC magnetron sputter deposition under four deposition conditions, combining powers of 50 and 100 W and argon gas pressures, 2 and 10 mTorr. Estimated deposition rates were between 0.08 and 3.5 nm s −1 . The films were examined using scanning electron microscopy, cross-sectioning using a focussed ion beam (FIB), X-ray diffraction and sheet resistance and Hall effect measurement. Room temperature deposition gave a predominant orientational texture of (111) rhombohedral. However, higher film thickness, low sputtering power, high sputtering gas pressure and deposition onto a heated substrate above 125 °C increase the fraction of (110) orientation. FIB cross-sectioning indicates that films deposited at room temperature have an irregular crystalline structure with voids, but those grown at 160 °C are denser with a better polycrystalline structure. Transport measurements indicate a dominance of conduction by electrons, with films deposited at room temperature having high sheet resistance, low sheet resistance being favoured by low sputtering pressure. Deposition at higher temperatures improves the conductivity but increases the Hall coefficient.

Title IV of the 1990 Clean Air Act Amendments (CAAA) established a market for transferable sulfur dioxide (SO2) emission allowances among electric utilities. This market offers firms facing high marginal abatement costs the opportunity to purchase the right to emit SO2from firms with lower costs, and this is expected to yield cost savings compared to a command‐and‐control approach to environmental regulation. This paper uses econometrically estimated marginal abatement cost functions for power plants affected by Title IV of the CAAA to evaluate the performance of the SO2allowance market. Specifically, we investigate whether the much‐heralded fall in the cost of abating SO2, compared to original estimates, can be attributed to allowance trading. We demonstrate that, for plants that use low‐sulfur coal to reduce SO2emissions, technical change and the fall in prices of low‐sulfur coal have lowered marginal abatement cost curves by over 50 percent since 1985. The flexibility to take advantage of these changes is the main source of cost reductions, rather than trading per se. In the long run, allowance trading may achieve cost savings of $700–$800 million per year compared to an “enlightened” command‐and‐control program characterized by a uniform emission rate standard. The cost savings would be twice as great if the alternative to trading were forced scrubbing. However, a comparison of potential cost savings in 1995 and 1996 with modeled costs of actual emissions suggests that most trading gains were unrealized in the first two years of the program.

While there is no question that population growth contributes to environmental degradation, its effects can be modified by economic growth and modern technology. As income grows, people will switch to energy sources other than firewood and will use modern agricultural techniques that reduce the demand for agricultural land. Similar effects are likely to be felt regarding pollution. As income grows, sanitation and waste-water treatment will improve, and pollution will be less of a problem at any level of population density. An important question for policy is whether, holding constant per capita income and other relevant factors, population pressures have a significant effect on environmental degradation. A first step is made toward providing such evidence. Specifically, an examination is made of the effect of population pressures on deforestation in 64 developing countries.

We propose a dedicated, ultra-deep spectroscopic survey in the near infrared (NIR), that will target a mass-limited sample of galaxies during two of the most fundamental epochs of cosmic evolution: the formation of the first galaxies (at z ≳ 6; cosmic dawn), and at the peak of galaxy formation activity (at redshift z ∼ 1–3; cosmic noon). By way of NIR observations (λ= 0.8–2μ m), it is possible to study the UV Lyman-α region in the former, and the optical rest-frame in the latter, allowing us to extract fundamental observables such as gas and stellar kinematics, chemical abundances, and ages, providing a unique legacy database covering these two crucial stages of cosmic evolution. The need to work in the NIR at extremely low flux levels makes a ground-based approach unfeasible due to atmospheric emission and absorption. Only with the largest facilities of the future (e.g. ELT) will be possible to observe a reduced set of targets, comprising at most of order thousands of galaxies. Likewise, from space, the small field of view of JWST and its use as a general purpose facility will yield a rather small set of high quality NIR spectra of distant galaxies (in the thousands, at best). Our project (codename Chronos) aims to produce ∼ 1 million high quality spectra, with a high S/N in the continuum, where information about the underlying stellar populations is encoded. The main science drivers are: The connection between the star formation history and the mass assembly history.The role of AGN and supernova feedback in shaping the formation histories of galaxies, with a quantitative estimate of quenching timescales.The formation of the first galaxies.The source of reionization.Evolution of the metallicity-mass relation, including [α/Fe] and individual abundances.Precision cosmology through detailed studies of the “baryon physics” of galaxy formation, probing the power spectrum over scales k ∼ 1 Mpc− 1.

Using plot level data, we estimate a bivariate probit model to explain land clearing and the siting of protected areas in North Thailand in 1986. The model suggests that protected areas (national parks and wildlife sanctuaries together) did not reduce the likelihood of forest clearing; however, wildlife sanctuaries may have reduced the probability of deforestation. Road building, by reducing impedance-weighted distance to market, has promoted clearing, especially near the forest fringe. We simulate the impact of further road building to show where road building is likely to have greatest impact and where it is likely to threaten protected areas.

Euclid is the next ESA mission devoted to cosmology. It aims at observing most of the extragalactic sky, studying both gravitational lensing and clustering over ~15,000 square degrees. The mission is expected to be launched in year 2020 and to last six years. The sheer amount of data of different kinds, the variety of (un)known systematic effects and the complexity of measures require efforts both in sophisticated simulations and techniques of data analysis. We review the mission main characteristics, some aspects of the the survey and highlight some of the areas of interest to this meeting.

The ESA space astrometry mission Gaia will measure the positions, parallaxes and proper motions of the 1 billion brightest stars on the sky. Expected accuracies are in the 7–25 μas range down to 15 mag and sub-mas accuracies at the faint limit (20 mag). The astrometric data are complemented by low-resolution spectrophotometric data in the 330–1000 nm wavelength range and, for the brighter stars, radial velocity measurements. The scientific case covers an extremely wide range of topics in galactic and stellar astrophysics, solar system and exoplanet science, as well as the establishment of a very accurate, dense and faint optical reference frame. With a planned launch around 2012 and an (extended) operational lifetime of 6 years, final results are expected around 2021. We give a brief overview of the science goals of Gaia, the overall project organisation, expected performance, and some key technical features and challenges.

Benefit-cost analysis can play an important role in legislative and regulatory policy debates on protecting and improving health, safety, and the natural environment. Although formal benefit-cost analysis should not be viewed as either necessary or sufficient for designing sensible public policy, it can provide an exceptionally useful framework for consistently organizing disparate information, and in this way, it can greatly improve the process and, hence, the outcome of policy analysis. If properly done, benefit-cost analysis can be of great help to agencies participating in the development of environmental, health, and safety regulations, and it can likewise be useful in evaluating agency decision-making and in shaping statutes.

Our comprehension of the history of star formation at \\(z>3\\) relies on rest-frame UV observations, yet this selection misses the most dusty and massive sources, yielding an incomplete census at early times. Infrared facilities such as Spitzer and the James Webb Space Telescope have revealed a hidden population at \\(z=3\\)-\\(6\\) with extreme red colours, named HIEROs (HST-to-IRAC extremely red objects), identified by the criterion \\(H_E-ch2>2.25\\). Recently, Euclid Early Release Observations (ERO) have made it possible to further study such objects by comparing Euclid data with ancillary Spitzer/IRAC imaging. We investigate a \\(232\\) arcmin\\(^2\\) area in the Perseus field using VIS and NISP photometry, complemented by the four Spitzer channels and ground-based MegaCam bands (\\(u\\), \\(g\\), \\(r\\), \\( H\\), \\(i\\), \\(z\\)). Applying the colour cut yields \\(121\\) HIEROs; after removing globular clusters, brown dwarfs, and unreliable cases through visual inspection of multiband cutouts, we obtain a final sample of \\(42\\) robust HIEROs. Photometric redshifts and physical properties are estimated with the SED-fitting code Bagpipes. From the resulting \\(z_phot\\) and \\(M_*\\) values, we compute the galaxy stellar mass function at \\(3.5

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