The economic value of delaying adaptation to sea-level rise: An application to coastal properties in Connecticut

The magnitude and frequency of coastal storms are expected to increase with rising global sea levels, which necessitates evaluating coastal flood adaptation measures. This study examines an important issue in the context of coastal flood protection, namely, the decision when to adopt protection measures. For any given coastal region, our benefit-cost framework allows us to determine the optimal timing of initiating protection that maximizes expected net benefits. We present an application of this framework to a coastal area in Connecticut. Our results suggest that the optimal timing of adopting protection may vary across different census blocks within the study area. We find that using a relatively low discount rate in the benefit-cost analysis implies greater heterogeneity in the timing decisions and earlier overall adoption, whereas, with higher discount rates, the timing decisions are reduced to a choice between early protection and no protection at all. If possible negative environmental and aesthetic impacts of sea barriers are taken into account, delaying protection would become more desirable, with the extent of delay being sensitive to the relative magnitude of one-time costs (e.g., loss of ocean view and recreational opportunities) vs. continuous costs (e.g., shoreline erosion and loss of wetlands).     

Measurement of Solar and Cosmic Radiation during Spaceflight

The external platform of the International Space Station (ISS) will provide aunique opportunity for exobiological studies under space conditions, e.g., spacevacuum, solar UV radiation, cosmic radiation, and temperature extremes. In orderto facilitate this research, ESA is developing the EXPOSE facility to be attachedto the External Pallet of the truss structure of the ISS. The experiment is plannedfor a duration of 18 months during the ISS early utilization period. Experimentson the ``Responses of Organisms to the Space Environment (ROSE)' will studythe survival of spores from bacteria, fungi, ferns, etc., under space conditions andthus investigate whether life could potentially survive extended travel through space.In parallel to the exposure of the biological material, the charged particle and solarextraterrestrial radiation will be measured with a multichannel dosimeter. Thisinstrument is based on two separate developments. The dosimeter which determinessolar radiation in four channels is based on the ground-based ELDONET (Europeanlight dosimeter network) instrument which has been developed to measure solar UVand visible radiation in three channels. The other part of the instrument is based on a256 channel dosimeter of cosmic radiation which was developed and used on theRussian space station Mir. A final miniature prototype has been developed to fit thespace available. The instrument incorporates the latest technologies such as SurfaceMounted Devices (SMDs), switchable amplifiers, as well as on-board microprocessorcontrol. Several software packages have been developed to record the solar visible andUV, and charged particle, radiations, to display them in graphical form and to store them for future analysis. All recorded data will be made available to the public via the Internet.     

New results on radiation effects on human health

Humans are exposed to ionizing radiation all the time, and it is known that it can induce a variety of harmful biological effects. Consequently, it is necessary to quantitatively assess the level of exposure to this radiation as the basis for estimating risks due to ionization radiation. During the Work Package 2400 of the COST-724/WG-2 action, a number of spacecraft and aircraft experiments have been performed with both active and passive detectors. A large data base has been created. In this contribution we would like to stress the results obtained and their importance in three particular directions: (i) Simultaneous investigation of galactic cosmic rays on aircraft and on the International Space Station (ISS); (ii) Onboard spacecraft neutron contribution as estimated on the basis of the comparison of results measured with MDU/Liulin equipment onboard ISS, foton capsule and a commercial aircraft flying at subsonic altitudes; (iii) Complex analysis of the results of long term measurements onboard a Czech Airlines aircraft. The results obtained are presented, analyzed, and discussed, and their complementary nature is underlined. The contribution represents a version of the Final Report of the Work Package 2400 of the COST-724/WG-2: Radiation Environment of the Earth.     

Pb isotope evidence for contaminant-metal dispersal in an international river system: The lower Danube catchment,Eastern Europe

Lead isotope signatures (²⁰⁷Pb/²⁰⁶Pb, ²⁰⁸Pb/²⁰⁶Pb, ²⁰⁸Pb/²⁰⁴Pb, ²⁰⁶Pb/²⁰⁴Pb), determined by magnetic sector ICP-MS in river channel sediment, metal ores and mine waste, have been used as geochemical tracers to quantify the delivery and dispersal of sediment-associated metals in the lower Danube River catchment. Due to a diverse geology and range of ore-body ages, Pb isotope signatures in ore-bodies within the lower Danube River catchment show considerable variation, even within individual metallogenic zones. It is also possible to discriminate between the Pb isotopic signatures in mine waste and river sediment within river systems draining individual ore bodies. Lead isotopic data, along with multi-element data; were used to establish the provenance of river sediments and quantify sedimentary contributions to mining-affected tributaries and to the Danube River. Data indicate that mining-affected tributaries in Serbia and Bulgaria contribute up to 30% of the river channel sediment load of the lower Danube River. Quantifying relative sediment contributions from mining-affected tributaries enables spatial patterns in sediment-associated metal and As concentrations to be interpreted in terms of key contaminant sources. Combining geochemical survey data with that regarding the provenance of contaminated sediments can therefore be used to identify foci for remediation and environmental management strategies.