The perceptions of local fishermen towards a hotel managed marine reserve in Vietnam

Marine Protected Areas (MPAs) often fail to meet ecological, social or economic objectives due to lack of effective management by government institutions. Partly in response to this failure, a number of marine reserves managed by the private sector, Hotel Managed Marine Reserves (HMMRs), have recently been established. In this study, we investigate changes to the social and economic conditions faced by local fishermen, following the establishment of two small reserves adjacent to a hotel in Vietnam, as well as their perceptions of the reserves' ability to produce spillover. The findings are used to gauge management performance and effectiveness of the HMMRs. Two surveys with different survey designs, targeting fishermen with different fishing techniques, produced conflicting results. Fishermen mainly dependent on beach seining mostly opposed the HMMRs and the prospect of more protected areas being established. Fishermen using other fishing techniques were generally in favor of the HMMRs, welcoming more protection and confirming spillover of fish, including large food fishes.     

Single-Column Model Intercomparison for a Stably Stratified Atmospheric Boundary Layer

The parameterization of the stably stratified atmospheric boundary layer is a difficult issue, having a significant impact on medium-range weather forecasts and climate integrations. To pursue this further, a moderately stratified Arctic case is simulated by nineteen single-column turbulence schemes. Statistics from a large-eddy simulation intercomparison made for the same case by eleven different models are used as a guiding reference. The single-column parameterizations include research and operational schemes from major forecast and climate research centres. Results from first-order schemes, a large number of turbulence kinetic energy closures, and other models were used. There is a large spread in the results; in general, the operational schemes mix over a deeper layer than the research schemes, and the turbulence kinetic energy and other higher-order closures give results closer to the statistics obtained from the large-eddy simulations. The sensitivities of the schemes to the parameters of their turbulence closures are partially explored.     

Thermalization by synchrotron absorption in compact sources: electron and photon distributions

The high-energy continuum in Seyfert galaxies and galactic black hole candidates is likely to be produced by a thermal plasma. There are difficulties in understanding what can keep the plasma thermal, especially during fast variations of the emitted flux. Particle–particle collisions are too inefficient in hot and rarefied plasmas, and a faster process is called for. We show that cyclo-synchrotron absorption can be such a process: mildly relativistic electrons thermalize in a few synchrotron cooling times by emitting and absorbing cyclo-synchrotron photons. The resulting equilibrium function is Maxwellian at low energies, with a high-energy tail when Compton cooling is important. Assuming that electrons emit completely self-absorbed synchrotron radiation and at the same time Compton scatter their own cyclo-synchrotron radiation and ambient UV photons, we calculate the time-dependent behaviour of the electron distribution function, and the final radiation spectra. In some cases, the 2–10 keV spectra are found to be dominated by the thermal synchrotron self-Compton process rather than by thermal Comptonization of UV disc radiation.     

Postglacial land uplift patterns of south Sweden and the Baltic Sea region

Comparison of the land uplift pattern for the last 10,300 years, shown by studies of raised shorelines of the Baltic Ice Lake, with the pattern of present-day land uplift of Fennoscandia, shows that significant regional changes of uplift pattern have taken place. Some of these changes seem to be related to a halt in ice retreat during the Younger Dryas cold stage. It is also probable that some observed anomalies in the present uplift are not of glacio-isostatic origin, but are possibly related to structures in the lower lithosphere and upper mantle or large scale tectonics.     

Wave Flow Simulations Over Arctic Leads

We investigate the flow over Arctic leads using a mesoscale numerical model, typical of both summer and winter, under idealised conditions. We find that Arctic leads may be the source of standing atmospheric internal gravity waves during both seasons. The summertime wave may be compared with the wave generated by a small ridge, though with the phase reversed. The mechanism for exciting the wave is found to be the internal boundary layer developing due to horizontal variations in surface temperature and roughness length. During the more exploratory wintertime simulations, with substantial temperature difference between the lead and the ice surface, we find that secondary circulations and intermittent wave-breaking may occur. The effects of the lead appear far downstream.     

The simulation of Arctic clouds and their influence on the winter surface temperature in present-day climate in the CMIP3 multi-model dataset

We investigate the influence of clouds on the surface energy budget and surface temperature in the sea-ice covered parts of the ocean north of the Arctic circle in present-day climate in nine global climate models participating in the Coupled Model Intercomparison Project phase 3, CMIP3. Monthly mean simulated surface skin temperature, radiative fluxes and cloud parameters are evaluated using retrievals from the extended AVHHR Polar Pathfinder (APP-x) product. We analyzed the annual cycle but the main focus is on the winter, in which large parts of the region experience polar night. We find a smaller across-model spread as well as better agreement with observations during summer than during winter in the simulated climatological annual cycles of total cloudiness and surface skin temperature. The across-model spread in liquid and ice water paths is substantial during the whole year. These results qualitatively agree with earlier studies on the present-day Arctic climate in GCMs. The climatological ensemble model mean annual cycle of surface cloud forcing shows good agreement with observations in summer. However, during winter the insulating effect of clouds tends to be underestimated in models. During winter, most of the models as well as the observations show higher monthly mean total cloud fractions, associated with larger positive surface cloud forcing. Most models also show good correlation between the surface cloud forcing and the vertically integrated ice and liquid cloud condensate. The wintertime ensemble model mean total cloud fraction (69%) shows excellent agreement with observations. The across-model spread in the winter mean cloudiness is substantial (36?C94%) however and several models significantly underestimate the cloud liquid water content. If the two models not showing any relationship between cloudiness and surface cloud forcing are disregarded, a tentative across-model relation exists, in such a way that models that simulate large winter mean cloudiness also show larger surface cloud forcing. Even though the across-model spread in wintertime surface cloud forcing is large, no clear relation to the surface temperature is found. This indicates that other processes, not explicitly cloud related, are important for the simulated across-model spread in surface temperature.     

ComparativeP-postlabeling analysis of DNA Adducts in Perch (Perca fluviatilis) from unpolluted and polluted areas in Swedish coastal waters

Perch (Perca fluviatilis), were sampled from unpolluted and polluted areas in Swedish coastal waters. The level of aromatic/hydrophobic DNA adducts in liver tissue was analyzed using the nucleas P1 version of the³²P-post-labeling assay. The level of total adducts measured in the individual fish from polluted areas was between 6 and 22 nmol of adducts/mol of nucleotides, and in the fish from the reference area between 0.2 and 0.6 nmol of adducts/mol of nucleotides.     

Estimation of winter leaf area index and sky view fraction for snow modelling in boreal coniferous forests: consequences on snow mass and energy balance

Leaf area index (LAI) and canopy coverage are important parameters when modelling snow process in coniferous forests, controlling interception and transmitting radiation. Estimates of LAI and sky view factor show large variability depending on the estimation method used, and it is not clear how this is reflected in the calculated snow processes beneath the canopy. In this study, the winter LAI and sky view fraction were estimated using different optical and biomass‐based approximations in several boreal coniferous forest stands in Fennoscandia with different stand density, age and site latitude. The biomass‐based estimate of LAI derived from forest inventory data was close to the values derived from the optical measurements at most sites, suggesting that forest inventory data can be used as input to snow hydrological modelling. Heterogeneity of tree species and site fertility, as well as edge effects between different forest compartments, caused differences in the LAI estimates at some sites. A snow energy and mass balance model (SNOWPACK) was applied to detect how the differences in the estimated values of the winter LAI and sky view fraction were reflected in simulated snow processes. In the simulations, an increase in LAI and a decrease in sky view fraction changed the snow surface energy balance by decreasing shortwave radiation input and increasing longwave radiation input. Changes in LAI and sky view fraction affected directly snow accumulation through altered throughfall fraction and indirectly snowmelt through the changed surface energy balance. Changes in LAI and sky view fraction had a greater impact on mean incoming radiation beneath the canopy than on other energy fluxes. Snowmelt was affected more than snow accumulation. The effect of canopy parameters on evaporation loss from intercepted snow was comparable with the effect of variation in governing meteorological variables such as precipitation intensity and air temperature. Copyright © 2012 John Wiley & Sons, Ltd.