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Ethics and intentional climate change 总被引:2,自引:0,他引:2
Dale Jamieson 《Climatic change》1996,33(3):323-336
In recent years the idea of geoengineering climate has begun to attract increasing attention. Although there was some discussion of manipulating regional climates throughout the 1970s and 1980s, the discussion was largely dormant. What has reawakened the conversation is the possibility that Earth may be undergoing a greenhouse-induced global warming, and the paucity of serious measures that have been taken to prevent it.In this paper I assess the ethical acceptability of ICC, based on my impressions of the conversation that is now taking place. Rather than offering a dispassionate analysis, I argue for a point of view. I propose a set of conditions that must be satisfied for an ICC project to be morally permissible and conclude that these conditions are not now satisfied. However, research on ICC should go forward so long as certain other conditions are met. I do not intend this to be the last word on the subject, but rather the first word. My hope is that others will be stimulated to think through the ethics of ICC. 相似文献
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A total of four vertical electrical soundings were conducted in a layered andesitic rock aquifer known in places to yield ground water with total dissolved solids (TDS) in excess of 2,000 milligrams per liter (mg/L). The objective of the soundings was to locate zones of moderate to high permeability but with acceptable chemical quality.
The resistivity of a geologic unit is a function that includes the quantity of total dissolved solids in the interstitial water and the distribution of the water within the unit. Thus, the resistivity of most granular soils and rocks is controlled more by porosity, water content and water quality than by the conductivity of the matrix materials.
The electrical data delimited a drill site where it was believed that ground water of acceptable chemical quality could be expected. Completion and test pumping of two exploration wells confirmed the electrical sounding results.
The first test well drilled prior to the survey yielded only small amounts of ground water with total dissolved solids in excess of 2,000 mg/L. The second exploration well drilled at the site as a result of the electrical study yielded in excess of 100 gallons per minute of ground water with total dissolved solids of 830 mg/L. 相似文献
The resistivity of a geologic unit is a function that includes the quantity of total dissolved solids in the interstitial water and the distribution of the water within the unit. Thus, the resistivity of most granular soils and rocks is controlled more by porosity, water content and water quality than by the conductivity of the matrix materials.
The electrical data delimited a drill site where it was believed that ground water of acceptable chemical quality could be expected. Completion and test pumping of two exploration wells confirmed the electrical sounding results.
The first test well drilled prior to the survey yielded only small amounts of ground water with total dissolved solids in excess of 2,000 mg/L. The second exploration well drilled at the site as a result of the electrical study yielded in excess of 100 gallons per minute of ground water with total dissolved solids of 830 mg/L. 相似文献
97.
Approximately 28,475 m3 of muddy sediments were dredged from a shoal in a South Carolina estuarine system and released near the surface at a nearby site having high tidal current velocities. Effects at the dredged sites included decreased macrofaunal abundance and changes in species composition. These effects appeared to be short term, with substantial recovery occurring within 3 months. Rapid recovery was primarily attributed to immigration through slumping of channel wall sediments similar to those dredged. Detrimental effects on benthic macrofauna in the area of open water disposal were minimal. Most differences noted in community structure between collection dates were attributed to sampling and seasonal variability. The absence of a major longterm disruption to the benthos in the disposal area was probably due to (1) strong tidal currents, which rapidly dispersed the moderate amount of mud sediments released; (2) surface disposal, permitting wider dispersal; and (3) disposal during late autumn, a period of low faunal recruitment. 相似文献
98.
The Galilean satellite eclipse technique for measuring the aerosol distribution in the upper Jovian atmosphere is described and applied using 30 color observations of the 13 May 1972 eclipse of Ganymede obtained with the 5-m Hale telescope. This event probes the South Temperate Zone. The observed aerosol lies above the visible cloud tops, is very tenuous and varies with altitude, increasing rapidly with downward passage through the tropopause. The aerosol extinction coefficient, κa (λ1.05 μm), is ~1.1 × 10?9 cm?1 in the lower stratosphere and ~1.1 × 10?8 cm?1 at the tropopause. The 1σ uncertainty in these values does not exceed 50% The observations require some aerosol above the tropopause but do not clearly determine its structure. The present analysis emphasizes an extended haze distribution, but the alternate possibility is not excluded that the stratospheric aerosol resides in a thin layer. The aerosol extinction increases with decreasing wavelength and indicates the particle radius to be ?0.2 μm. Larger radii are impossible. These overall results confirm Axel's (1972) suggestion of a small quantity of dust above the Jovian cloud tops and the optical depths are consistent with those required to explain the low uv albedo. 相似文献
99.
We report new visual and 20-μm photometry obtained when Hektor was seen nearly along its rotation axis. The visual amplitude was near its minimum, only 0.06 mag, confirming the Dunlap-Gehrels (1969) rotation model. The new observations confirm and refine the large size and low albedo assigned by Cruikshank (1977) from observations of the opposite rotation pole. The albedo of this pole is found to be pv = 0.022 ± 0.003, overlapping the uncertainty of Cruikshank's 0.03 value for the opposite pole. The low albedo makes Hektor roughly three times bigger than estimates of a few years ago. The light variations are interpreted as due to elongated shape. If this is correct, Hektor is both the largest and most elongated known Trojan, as well as being the most elongated known asteroid of its size. From considerations of Trojans' peculiar properties, we propose that Hektor is a somewhat dumbbell shaped object roughly 150 × 300 km in size, resulting from partial coalescence of two primitive spheroidal planetesimals during a relatively low-speed collision in the Trojan Lagrangian cloud, with energy too low for complete disruption. Calculations supporting this model indicate that Trojans may be less altered by collisions than belt asteroids. Observations in 1979 and 1980 can help test this model. A note added on July 17, 1978 relates our result to recent evidence of possible binary asteroid pairs, which may also arise from early low-velocity asteroid-asteroid interactions. 相似文献
100.
Heidi E. Kretser Elliot Dale Leslie Karasin Liba Pejchar Sarah E. Reed 《社会与自然资源》2019,32(9):1021-1039
Conservation Development (CD) is a land-use tool to reduce the impacts of development on natural resources, yetthe use of CD is highly variable. We used a collaborative conservation model to examine factors influencing adoption and implementation to improve the future application of CD. We interviewed 2–3 individuals including planners, board members, and developers (n?=?46) from 16 rural communities in the intermountain west and northeast U.S. Motivations to preserve rural character or comply with state statutes drove adoption. Greater capacity such as outside expertise, model regulations, and iterative revisions of ordinances was associated with stronger ordinances. Adoption processes including ample dialog across diverse constituents, especially those overseeing subdivision development, facilitated higher rates of implementation. Concerns over open space management, lack of successful CD examples, and inexperience with CD posed barriers to implementation. Understanding social context revealed the strengths and shortcomings of CD and provided guidance for strategically engaging communities in private lands conservation. 相似文献