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Reducing the impacts from climate change requires people to make decisions that may prompt substantial changes in their lives. One possible way to help them is with personalized decision aids. Here we describe a method for evaluating such aids, in terms of how they affect users’ understanding of their situation, defined in terms of their (a) knowledge, (b) consistency of preferences, and (c) active mastery of the material. Our method provides a simple way to evaluate the usability of climate-change decision aids, and to address concerns that the choice of display could bias users’ attitudes. We demonstrate it with the Surging Seas Risk Finder, a decision aid focused on coastal flooding (http://sealevel.climatecentral.org/).  相似文献   
23.
Agricultural soils are a major source of atmospheric nitrous oxide (N2O), a potent greenhouse gas (GHG). Because N2O emissions strongly depend on soil type, climate, and crop management, their inventory requires the combination of biophysical and economic modeling, to simulate farmers’ behavior. Here, we coupled a biophysical soil-crop model, CERES-EGC, with an economic farm type supply model, AROPAj, at the regional scale in northern France. Response curves of N2O emissions to fertilizer nitrogen (Nf) inputs were generated with CERES-EGC, and linearized to obtain emission factors. The latter ranged from 0.001 to 0.0225 kg N2O-N kg???1 Nf, depending on soil and crop type, compared to the fixed 0.0125 value of the IPCC guidelines. The modeled emission factors were fed into the economic model AROPAj which relates farm-level GHG emissions to production factors. This resulted in a N2O efflux 20% lower than with the default IPCC method. The costs of abating GHG emissions from agriculture were calculated using a first-best tax on GHG emissions, and a second-best tax on their presumed factors (livestock size and fertilizer inputs). The first-best taxation was relatively efficient, achieving an 8% reduction with a tax of 11 €/ t-CO2-equivalent, compared to 68 €/t-CO2 eq for the same target with the second-best scheme.  相似文献   
24.
Geophysical monitoring and evaluation of coastal plain aquifers   总被引:1,自引:0,他引:1  
We use time domain electromagnetic (TDEM) soundings to monitor ground water conditions beneath the coastal plain in eastern North Carolina. The TDEM method measures the earth's response to an induced electromagnetic field. The resulting signal is converted, through a complex inversion process, to apparent resistivity values, which can be directly correlated to borehole resistivity logs. TDEM soundings are used to map the interface between fresh and salt water within coastal aquifers, and estimate depth to basement when siting new monitoring wells. Focused TDEM surveys have identified areas of salt water encroachment caused by high volumes of discharge from local supply wells. Electromagnetic sounding, when used in tandem with the state's network of monitoring wells, is an accurate and inexpensive tool for evaluating fresh water/salt water relationships on both local and regional scales within coastal plain aquifers.  相似文献   
25.
Mineralogy and Petrology - The history of staurolite (1792-present) demonstrates how long it takes for superseded teachings to be discarded in favor of new results, witness the long estrangement of...  相似文献   
26.
Performing long-term pump tests, single-well aquifer tests and long-term ground water monitoring were, in the past, considered costly and labor-intensive tasks. However, because of recent advances in portable data acquisition systems, these field tests can be performed in a relatively cost-effective and efficient manner. Certain data acquisition systems (DAS) have unique options available. Recently developed and commonly used computers are the Envirolab®, the Paroscientific®, and the In-Situ®. The use of implementing DAS in ground water field studies has proved to be successful when compared to the many disadvantages of performing those tasks manually. Successful acquisition of aquifer characterization data using computerized methods is highly dependent on the implementation of proper field programming and operational procedures. In order to provide high qualify and meaningful data, the field operator must be familiar with proper equipment implementation and programming instructions. Once familiar with these procedures, the use of DAS in the field provides a cost-effective and efficient tool for aquifer testing.  相似文献   
27.
VIRGO: Experiment for helioseismology and solar irradiance monitoring   总被引:1,自引:0,他引:1  
The scientific objective of the VIRGO experiment (Variability of solar IRradiance and Gravity Oscillations) is to determine the characteristics of pressure and internal gravity oscillations by observing irradiance and radiance variations, to measure the solar total and spectral irradiance and to quantify their variability over periods of days to the duration of the mission. With these data helioseismological methods can be used to probe the solar interior. Certain characteristics of convection and its interaction with magnetic fields, related to, for example, activity, will be studied from the results of the irradiance monitoring and from the comparison of amplitudes and phases of the oscillations as manifest in brightness from VIRGO, in velocity from GOLF, and in both velocity and continuum intensity from SOI/MDI. The VIRGO experiment contains two different active-cavity radiometers for monitoring the solar constant, two three-channel sunphotometers (SPM) for the measurement of the spectral irradiance at 402, 500 and 862 nm, and a low-resolution imager (LOI) with 12 pixels, for the measurement of the radiance distribution over the solar disk at 500 um. In this paper the scientific objectives of VIRGO are presented, the instruments and the data acquisition and control system are described in detail, and their measured performance is given.died 13 October 1994  相似文献   
28.
Communities of chemosynthetic fauna that depend on seeping oil and gas have been found in the Gulf of Mexico at approximately 45 sites between 88°W and 95°W and between the 350 and 2,200 m isobaths. Investigations suggest that the number of sites and the range of occurrence will increase with additional exploration. The dominant fauna consist of species within four groups: tube worms, seep mussels, epibenthic clams, and infaunal clams. These species co-occur to some degree, but tend to form assemblages dominated by a single group. Community development is closely coupled to the geological and geochemical processes of seepage.  相似文献   
29.
Thongs  Gabrielle 《Natural Hazards》2019,98(2):593-619
Natural Hazards - Flooding disasters are frequent and devastating events in Trinidad. Moderate amounts of precipitation burst riverbanks in central business districts, cities, and towns within the...  相似文献   
30.
Water temperatures in mountain streams are likely to rise under future climate change, with negative impacts on ecosystems and water quality. However, it is difficult to predict which streams are most vulnerable due to sparse historical records of mountain stream temperatures as well as complex interactions between snowpack, groundwater, streamflow and water temperature. Minimum flow volumes are a potentially useful proxy for stream temperature, since daily streamflow records are much more common. We confirmed that there is a strong inverse relationship between annual low flows and peak water temperature using observed data from unimpaired streams throughout the montane regions of the United States' west coast. We then used linear models to explore the relationships between snowpack, potential evapotranspiration and other climate-related variables with annual low flow volumes and peak water temperatures. We also incorporated previous years' flow volumes into these models to account for groundwater carryover from year to year. We found that annual peak snowpack water storage is a strong predictor of summer low flows in the more arid watersheds studied. This relationship is mediated by atmospheric water demand and carryover subsurface water storage from previous years, such that multi-year droughts with high evapotranspiration lead to especially low flow volumes. We conclude that watershed management to help retain snow and increase baseflows may help counteract some of the streamflow temperature rises expected from a warming climate, especially in arid watersheds.  相似文献   
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