Urban meteorological modelling for nuclear emergency preparedness

The main objectives of the current EU project “Integrated Systems for Forecasting Urban Meteorology, Air Pollution and Population Exposure” (FUMAPEX) are the improvement of meteorological forecasts for urban areas, the connection of numerical weather prediction (NWP) models to urban air pollution and population dose models, the building of improved urban air quality information and forecasting systems, and their application in cities in various European climates. In addition to the forecast of the worst air-pollution episodes in large cities, the potential use of improved weather forecasts for nuclear emergency management in urban areas, in case of hazardous releases from nuclear accidents or terror acts, is considered. Such use of NWP data is tested for the Copenhagen metropolitan area and the Øresund region.The Danish Meteorological Institute (DMI) is running an experimental version of the HIRLAM NWP model over Zealand including the Copenhagen metropolitan area with a horizontal resolution of 1.4 km, thus approaching the city-scale. This involves 1-km resolution physiographic data with implications for the urban surface parameters, e.g. surface fluxes, roughness length and albedo. For the city of Copenhagen, the enhanced high-resolution NWP forecasting will be provided to demonstrate the improved dispersion forecasting capabilities of the Danish nuclear emergency preparedness decision–support system, the Accident Reporting and Guidance Operational System (ARGOS), used by the Danish Emergency Management Agency (DEMA).Recently, ARGOS has been extended with a capability of real-time calculation of regional-scale atmospheric dispersion of radioactive material from accidental releases. This is effectuated through on-line interfacing with the Danish Emergency Response Model of the Atmosphere (DERMA), which is run at DMI. For local-scale modelling of atmospheric dispersion, ARGOS utilises the Local-Scale Model Chain (LSMC), which makes use of high-resolution DMI-HIRLAM NWP model data provided to DEMA by DMI four times a day under operational surveillance and covering Denmark and surroundings. The integration of DERMA in ARGOS is effectuated through automated on-line digital communication and exchange of data. The calculations are carried out in parallel for each NWP model to which DMI has access, thereby providing a mini-ensemble of dispersion forecasts for the emergency management.     

Swidden agriculture in a protected area: the Matsigenka native communities of Manu National Park, Peru

In this study, we investigate whether traditional swidden agriculture on nutrient-poor tropical soils can sustainably support a growing indigenous population within Manu National Park, Peru. Based on interviews with 50 Matsigenka farmers, as well as GPS mapping and field visits, we established the location and size of all 124 swidden gardens cultivated in 2000 and 2001. Using a GIS-based soil map of Manu Park, we identify the total extent of potential arable land (1) throughout the park zones currently available for Matsigenka habitation, and (2) within the vicinity of the two study communities. Taking into account current per capita garden size, cultivation and fallow practices, we calculate the maximum human carrying capacity of swidden agriculture for (1) all available park zones and (2) the immediate vicinity of the two current communities. Even given the second, highly limited scenario, the sustainable human carrying capacity is estimated to be 2,138 individuals, which is far higher than the current population of about 420 people. Thus, arable land does not appear to be a limiting factor for the growth of the indigenous population in Manu Park at the current time. Other possible limiting factors for population growth are identified and discussed. We conclude that a conservation policy of population stabilization around the current settlements is viable in that it will not result in reduced resource availability over the next few decades, and that the challenge is to identify and mitigate the forces causing population fissioning and spread. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.     

Characteristics of Filoviridae: Marburg and Ebola Viruses

Filoviruses are enveloped, nonsegmented negative-stranded RNA viruses. The two species, Marburg and Ebola virus, are serologically, biochemically, and genetically distinct. Marburg virus was first isolated during an outbreak in Europe in 1967, and Ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern Sudan and northern Zaire. Although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filoviruses still remains a mystery.     

Environmental geology: A hazard in its own right?

Environmental geology and its more restricted counterpart, urban geology, are defined. Their development since the early 1970s is assessed with respect to needed research in the fields of natural hazards and disasters. Some pitfalls of the environmental geology approach to hazards are pointed out, and it is suggested that the subject would benefit from certain alterations in its aims and scope: principally towards a closer identification with the similar field of natural hazards.     

Use and interaction of navigation strategies in regionalized environments

In this work, three experiments are reported that studied the use and interaction of navigation strategies both during the learning of a virtual environment and during subsequent route planning tasks. Special interest concerned the role of regions within the environments. Results from Experiment 1 suggest that the regions are perceived and encoded in spatial memory very early during the process of learning an environment. During navigation such regional information could be used to overcome missing or imprecise spatial information on the detailed level. Experiments 2 and 3 studied the use and interaction of route planning strategies that are applied after an environment has been learned. Results suggest (i) that human route planning takes into account region-connectivity and is not based on place-connectivity alone, (ii) that route planning takes into account the distribution of multiple target locations and (iii) that route planning takes into account the complexity of alternative paths.     

ESTIMATING THE DEMAND FOR IRRIGATION WATER IN THE CENTRAL VALLEY OF CALIFORNIA1

ABSTRACT: This paper computes estimates of the demand for surface irrigation water directly from disaggregated profit functions for fields in the San Joaquin Valley of California. It finds that treating delivered surface water and pumped ground water as separate, imperfectly substitutable inputs to production matters a great deal. We find substantial ranges of inelastic demand for delivered water, and thresholds across which demand then becomes highly elastic. The results imply that moves toward freer water markets could lead to large quantities reallocated from agriculture to urban uses in the Western U.S., but would require large price increases and would induce extensive ground water mining and major changes in cropping patterns. While these results are dependent on our particular model and simplifying assumptions, evidence exists that they may be robust.     

Application of recombinant gene technology for production of polyhydroxyalkanoic acids: Biosynthesis of poly(4-hydroxybutyric acid) homopolyester

Screening of a large number of bacteria revealed several strains, which utilize 1,4-butanediol and/or 4-hydroxybutyric acid (4HB) as a carbon source for growth and for synthesis of polyhydroxyalkanoic acids (PHA) containing 4HB as one constituent among others (mostly 3-hydroxybutyric acid). However, none of the wild-type strains investigated in this study was able to produce a homopolyester consisting solely of 4HB. Only several poly(3-hydroxybutyric acid)-leaky mutants ofAlcaligenes eutrophus strain JMP222 synthesized poly(4HB) homopolyester, which amounted to approximately 10% (w/w) of the cellular dry matter. If the PHA synthase structural gene ofA. eutrophus strain H16 was expressed in these mutants, the amount of poly(4HB) was increased to approximately 30% (w/w). The occurrence of poly(4HB) was demonstrated by gas chromatographic as well as¹H and¹³C nuclear magnetic resonance spectroscopic analysis.Paper presented at the Bio/Environmentally Degradable Polymer Society—Second National Meeting, August 19–21, 1993, Chicago, Illinois.     

A COMPARISON OF METHODS OF ESTIMATING MEAN WATERSHED SLOPE1

ABSTRACT: Ten topographic analysis methods were employed to estimate watershed mean slopes for 13 small forested watersheds (32 to 131 mi²) in East Texas. Of the ten methods employed, the mean slope curve is the most accurate but also the most tedious and laborious one. The method can be simplified by measuring only the lengths of five contours and the areas between these contours within the watershed with little loss of its accuracy. Watershed slopes estimated by the contour length method, the grid contour method, the systematic slope sampling method, and the simplified contour length method are satisfactory for general purposes and relatively simple. The watershed circumference-stream length method, the length-width axis method, the Justin method, and the regression plane method are not suitable for estimating watershed slopes in East Texas without modification.