The joint Industry/DOE Workshop on the Interactions of Climate and Energy was designed to bring the providers of climate information and services together with users and representatives of the oil, gas, coal, and electric utility sectors of the U.S. energy industry. Primary discussion topics included current uses of climate data, the perceived impacts of climatic anomalies on the energy sector, ways to improve the uses of climate data, and recommendations for future research by the climate community. This opportunity for such interaction generated a universal agreement among the participants that more frequent exchanges between the providers and users of climate information be planned and that better communication between the providers and users of climate data and services be established. The workshop proceedings, which is being published by the Department of Energy, presents studies on the application of existing data to the diagnosis of the climatic component in energy supply and demand and the short-term prediction of regional scale energy requirements. Staff members of the National Oceanic and Atmospheric Administration's (NOAA) National Climate Data Center (NCDC) and Climate Analysis Center (CAC) review the currently available climate data and services. Four panel reports identify and enumerate the impacts of climate on each of the segments of the energy industry and offer recommendations for improvements, further research, and, in some cases, concepts for practical demonstrations of immediate potential value to the pertinent energy sector. The panel findings and the presentations of the invited speakers contain several common themes: the need for improved data formats, the significant potential benefits of increased lead time for the seasonal climate forecast, and the necessity for improved accuracy in the forecasts of monthly and seasonal means and extremes of temperature and precipitation. Workshop participants fully recognized the difficulty of making “real” progress on some of these commonly stated objectives; however, they also recognized that the benefits of striving to achieve these goals may, indeed, be sufficiently great to justify the quest for progress through focused research efforts.

The anomalous groundwater mound and resulting flow regime associated with the Aardvark underground nuclear explosion have been examined. The initial anomalous groundwater mound was estimated to be about 200 m high and 250 m in radius with a central depression. The major mechanism for mound development was probably compaction of nearly saturated rock surrounding the explosion. Results of the calculations indicate that water first flowed into the collapsed zone, then radially outward with early velocities approximately 200 times preshot flow velocities. After about 400 days the magnitude of the anomalous flow had declined to or below the magnitude of the preshot groundwater flow rates. Ideally ‘traced tagged’ water particles initially near the edge of the collapsed zone are estimated to have moved outward about 6.2 m during the first 100 days after the explosion. It is shown that the anomalous mound does not significantly increase the migration of radionuclides from this explosion environment.

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An accidental atmospheric release of plutonium dioxide particles from a nuclear facility may result in deposition of a major fraction of the particles within a few km downwind. Estimates of plume depletion as a function of distance were computed using the atmospheric-diffusion particle-in-cell code. This code is capable of estimating the atmospheric transport, diffusion, gravitational settling, and dry deposition of the PuO, particles within a three-dimensional grid under conditions of boundary layer, stratified shear flow. The calculations show the effect on plume depletion of varying the source height, the particle size, and the type of vegetation. Pasquill F stability was chosen for applicability to nuclear facility safety analyses. The fraction of activity remaining in the plume at a given distance increases with source height and is inversely affected by surface roughness. For submicrometer particles emitted at a height of 10m, the fraction remaining airborne at 30 km downwind is about 0.5 over agricultural land covered with low growing, densely planted leafy vegetables and only 0.2 over brushland. Because of their large gravitational settling velocities, essentially all particles greater than 5 pm emitted at a 10-m height are deposited within 5 km of the facility. As the source height is increased, the effect of varying the type of vegetation becomes minimal. Hence, for a 100-m source height, the fraction of submicrometer-size particles remaining airborne is roughly 0.9 at 30 km over agricultural land as well as brushland and about 0.25 of the 5-pm particles are still airborne at 30 km.

A simple two‐dimensional model is developed of cratering physics for high‐explosive sources in alluvium during the surface gas‐acceleration phase of excavation. The required initial conditions for the model are knowledge of the earth's free‐surface topography and motion at the time the surface gas acceleration begins (tG) and knowledge of the cavity pressure and volume. At tG the overburden material—that material between the cavity and the earth's free surface—is assumed to be homogeneous, incompressible fluid. At this time the cavity is approximated as follows: (a) the radius of the lower hemisphere is calculated by a one‐dimensional hydrodynamic plastic‐elastic model of the response of a geologic medium to an explosive source, and (b) the cavity configuration above the shot horizon is calculated from mass conservation of the overburden material and the calculated free‐surface topography at the time tG. In the model, the upper cavity surface is subdivided into elemental surface areas, and mass zones are defined which subtend these elemental surface areas. Newton's second law of motion with a simple phenomenological frictional force (calibrated on the Scooter event) is applied to each mass element. The cavity gas is assumed to behave adiabatically. The physical laws, assumptions, and initial conditions cited above provide a basis for the numerical simulation of the cavity evolution, mound development, and formation of the lip through up‐thrust during the surface gas‐acceleration phase of excavation. With the development of a calibrated numerical simulation model of excavation processes during the surface gas‐acceleration phase, it is appropriate to explore the use of the model for estimating the apparent crater radii and depth for 0.5‐kt high‐explosive sources at various emplacement depths. Assuming a reasonable angle of repose for alluvium (45°), we have prepared estimates of the apparent crater radii for scaled depth of burst from about 10 to 65 m/kt1/3.4. These estimated crater radii compare very favorably with the observed (scaled) crater radii for high explosives in alluvium. The apparent (scaled) crater depths, for certain types of craters, are also calculated. Perhaps the most significant contribution of the study is the development of a physical model for calculating the time history of the mound, the lip formation, and the cavity geometry during the surface gas‐acceleration phase of cratering.