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Satellite remote sensing is providing a systematic, synoptic framework for advancing scientific knowledge of the Earth as a complex system of geophysical phenomena that, directly and through interacting processes, often lead to natural hazards. Improved and integrated measurements along with numerical modeling are enabling a greater understanding of where and when a particular hazard event is most likely to occur and result in significant socioeconomic impact. Geospatial information products derived from this research increasingly are addressing the operational requirements of decision support systems used by policy makers, emergency managers and responders from international and federal to regional, state and local jurisdictions. This forms the basis for comprehensive risk assessments and better-informed mitigation planning, disaster assessment and response prioritization. Space-based geodetic measurements of the solid Earth with the Global Positioning System, for example, combined with ground-based seismological measurements, are yielding the principal data for modeling lithospheric processes and for accurately estimating the distribution of potentially damaging strong ground motions which is critical for earthquake engineering applications. Moreover, integrated with interferometric synthetic aperture radar, these measurements provide spatially continuous observations of deformation with sub-centimeter accuracy. Seismic and in situ monitoring, geodetic measurements, high-resolution digital elevation models (e.g. from InSAR, Lidar and digital photogrammetry) and imaging spectroscopy (e.g. using ASTER, MODIS and Hyperion) are contributing significantly to volcanic hazard risk assessment, with the potential to aid land use planning in developing countries where the impact of volcanic hazards to populations and lifelines is continually increasing. Remotely sensed data play an integral role in reconstructing the recent history of the land surface and in predicting hazards due to flood and landslide events. Satellite data are addressing diverse observational requirements that are imposed by the need for surface, subsurface and hydrologic characterization, including the delineation of flood and landslide zones for risk assessments. Short- and long-term sea-level change and the impact of ocean-atmosphere processes on the coastal land environment, through flooding, erosion and storm surge for example, define further requirements for hazard monitoring and mitigation planning. The continued development and application of a broad spectrum of satellite remote sensing systems and attendant data management infrastructure will contribute needed baseline and time series data, as part of an integrated global observation strategy that includes airborne and in situ measurements of the solid Earth. Multi-hazard modeling capabilities, in turn, will result in more accurate forecasting and visualizations for improving the decision support tools and systems used by the international disaster management community.

A controlled laboratory experiment was carried out to investigate growth-dependent otolith increment formation in herring larvae under constant and variable feeding regimes. Larvae of Norwegian spring-spawning herring were reared at 88C for 46 days using nominal prey densities of 40 (low) or 1200 (high) prey l ˇ1 . Two groups of larvae were offered constant prey levels throughout the experiment (high or low), whereas the prey levels in two other groups were temporarily increased or decreased. All groups were marked twice with alizarin complexone immersion when prey levels were changed (day 18 and day 32 post hatching). Overall survival in the experiment ranged from 36 to 51%, and daily growth in length ranged from 0.02 to 0.4 mm per day. Average daily otolith growth (sagitta) in the low-prey-density group was below 0.2 mm per day, and the apparent increment formation rate was significantly below 1 per day. The high-prey-density group had an increment deposition rate of about 1 per day after the first marking, and these increments averaged 1.1 mm in width. The alizarin marking confirmed that otolith growth responded to increased prey densities and larval growth within a few days, but the response to deteriorating feeding conditions was slower. The apparent increment deposition rate was below 1 per day during the inter-mark period at average otolith growth rates of less than 1 mm per day. In the present study the increment deposition rate was correlated both with larval growth and larval size. The otolith growth pattern confirmed that there was a high correlation between larval size at sampling and previous larval size both within and between groups (rs>0.6 after 4 weeks). The ratios of otolith sizes at different ages within individual larvae could be used to identify groups of larvae and to a large extent also individual larvae originating from different prey regimes. # 2000 Elsevier Science B.V. All rights reserved.

In face-to-face surveys interviewers play a crucial role in making contact with and gaining cooperation from sample units. While some analyses investigate the influence of interviewers on nonresponse, they are typically restricted to single-country studies. However, interviewer training, contacting and cooperation strategies as well as survey climates may differ across countries. Combining call-record data from the European Social Survey (ESS) with data from a detailed interviewer questionnaire on attitudes and doorstep behavior we find systematic country differences in nonresponse processes, which can in part be explained by differences in interviewer characteristics, such as contacting strategies and avowed doorstep behavior.