Energy and policy providing for sustainable rural livelihoods in remote locations – The case of Cuba

Modern, small-scale renewable energy technology has the potential to enable and sustain rural livelihoods, particularly in developing countries remote locations without access to the grid. Yet, the provision of rural energy to isolated communities might not achieve the desired long-term result unless its development is part of wider national policy geared to sustainable development and social equity. This article shows how a combination of technology and policy targeted at the improvement of livelihoods in rural areas is the best solution for maximising the capacity of renewable energy to deliver services. It pinpoints the transforming processes and the institutions participating in the delivery of energy technology. This work draws on the Cuban experience of renewable energy technology, that country’s efforts to improve quality of life for remote populations, and its pledge to promote environmental sustainability. Using a sustainable livelihoods approach, the results of a survey in a rural community are analysed in the framework of existing assets and policies. The article describes how it is not only local users who benefit from a comprehensive technical, social and environmental energy approach. The same governmental administration that promotes such services has much to gain from technology that works well, benefits the poor in remote locations and protects the environment within its larger policy promoting sustainable and egalitarian society.     

Effects of changing solution chemistry on Fe/Fe isotope fractionation in aqueous Fe-Cl solutions

The range in ⁵⁶Fe/⁵⁴Fe isotopic compositions measured in naturally occurring iron-bearing species is greater than 5‰. Both theoretical modeling and experimental studies of equilibrium isotopic fractionation among iron-bearing species have shown that significant fractionations can be caused by differences in oxidation state (i.e., redox effects in the environment) as well as by bond partner and coordination number (i.e., nonredox effects due to speciation).To test the relative effects of redox vs. nonredox attributes on total Fe equilibrium isotopic fractionation, we measured changes, both experimentally and theoretically, in the isotopic composition of an Fe²⁺-Fe³⁺-Cl-H₂O solution as the chlorinity was varied. We made use of the unique solubility of FeCl₄⁻ in immiscible diethyl ether to create a separate spectator phase against which changes in the aqueous phase could be quantified. Our experiments showed a reduction in the redox isotopic fractionation between Fe²⁺- and Fe³⁺-bearing species from 3.4‰ at [Cl⁻] = 1.5 M to 2.4‰ at [Cl⁻] = 5.0 M, due to changes in speciation in the Fe-Cl solution. This experimental design was also used to demonstrate the attainment of isotopic equilibrium between the two phases, using a ⁵⁴Fe spike.To better understand speciation effects on redox fractionation, we created four new sets of ab initio models of the ferrous chloride complexes used in the experiments. These were combined with corresponding ab initio models for the ferric chloride complexes from previous work. At 20 °C, 1000 ln β (β = ⁵⁶Fe/⁵⁴Fe reduced partition function ratio relative to a dissociated Fe atom) values range from 6.39‰ to 5.42‰ for Fe(H₂O)₆²⁺, 5.98‰ to 5.34‰ for FeCl(H₂O)₅⁺, and 5.91‰ to 4.86‰ for FeCl₂(H₂O)₄, depending on the model. The theoretical models predict ferric-ferrous fractionation about half as large (depending on model) as the experimental results.Our results show (1) oxidation state is likely to be the dominant factor controlling equilibrium Fe isotope fractionation in solution and (2) nonredox attributes (such as ligands present in the aqueous solution, speciation and relative abundances, and ionic strength of the solution) can also have significant effects. Changes in the isotopic composition of an Fe-bearing solution will influence the resultant Fe isotopic signature of any precipitates.     

Iceberg discharge to the Chukchi shelf during the Younger Dryas

The extent of glaciation in northwestern Alaska, the source of sediment supply to the Chukchi shelf and slope, and the movement of sea ice and icebergs across the shelf during the last glacial maximum (LGM) remain poorly constrained. Here we present geophysical and geological data from the outer Chukchi margin that reveal a regionally extensive, heavily ice-scoured surface ∼ 5-8 m below the modern seafloor. Radiocarbon dating of this discrete event yields age estimates between 10,600 and 11,900 ¹⁴C yr BP, indicating the discharge event occurred during the Younger Dryas. Based on mineralogy of the ice-rafted debris, the icebergs appear to be sourced from the northwestern Alaskan margin, which places important constraints on the ice extent in northern Alaska during the LGM as well as existing circulation models for the region.     

Biogeochemical sampling for mineral exploration in arid terrains: Tanami Gold Province,Australia

Vegetation sampling is an effective mineral exploration technique in areas of transported cover in the Tanami Gold Province where other techniques have been of limited success. This research tests the ability of plants to show signatures of mineralisation as well as the optimum scale of sampling for first-pass mineral exploration surveys. The semi-arid Tanami Gold Province in northern Australia encompasses nearly 160,000 km² and is a highly prospective yet under-explored region due to transported cover masking mineralisation. Various dominant plant species were sampled along transects across four sites of Au mineralisation in the Tanami (Larranganni, Hyperion, Coyote and Titania). Snappy gum (Eucalyptus brevifolia) gave a geobotanical (plant distribution) and lithological (S and Zn) signature of an underlying geological structure known to host Au mineralisation at the Coyote Prospect. Soft spinifex (Triodia pungens) provided an Au, As, ± Zn, ± S, and ± Ce expression of buried Au mineralisation at Coyote and Titania. At the Hyperion prospect, mineralisation is located at the contact between granite and dolerite, and biogeochemical signatures from snappy gum and dogwood (Acacia coriacea) show elevated ± Au, Ce, S and Zn that corresponded to the contact. Biogeochemistry is able to determine the location of mineralisation at each site, except at Hyperion where the sample density was too low. It is able to identify underlying substrate differences, however, background knowledge relating to regolith, geology, hydrology and geophysics are important in aiding the interpretation of the elemental data. It was found that having too few samples (at Hyperion) there was insufficient useful information for mineral exploration. Grid coverage of an area (at Titania) provided information on mineralisation and groundwater dispersion plumes; however, in this case a single transect over the same area would have been sufficient for a first-pass mineral exploration survey.     

The Solar Optical Telescope for the Hinode Mission: An Overview

The Solar Optical Telescope (SOT) aboard the Hinode satellite (formerly called Solar-B) consists of the Optical Telescope Assembly (OTA) and the Focal Plane Package (FPP). The OTA is a 50-cm diffraction-limited Gregorian telescope, and the FPP includes the narrowband filtergraph (NFI) and the broadband filtergraph (BFI), plus the Stokes Spectro-Polarimeter (SP). The SOT provides unprecedented high-resolution photometric and vector magnetic images of the photosphere and chromosphere with a very stable point spread function and is equipped with an image-stabilization system with performance better than 0.01 arcsec rms. Together with the other two instruments on Hinode (the X-Ray Telescope (XRT) and the EUV Imaging Spectrometer (EIS)), the SOT is poised to address many fundamental questions about solar magnetohydrodynamics. This paper provides an overview; the details of the instrument are presented in a series of companion papers. M. Otsubo is a former NAOJ staff scientist.     

Acoustic Radius Measurements from MDI and GONG

We study the temporal autocorrelation function (ACF) of global solar oscillations. It is well known that the “large frequency separation” is proportional to the solar acoustic radius. We analyze the ACF of MDI and GONG spherical-harmonic-coefficient time series for degrees ?=0?3. Acoustic radius measurements obtained from the first dominant peak locations of the ACF show a significant anticorrelation with solar cycle. This technique can be a useful tool to search for stellar activity.     

Helioseismic ring analysis of CME source regions

We apply the ring diagram technique to source regions of halo coronal mass ejections (CMEs) to study changes in acoustic mode parameters before, during, and after the onset of CMEs. We find that CME regions associated with a low value of magnetic flux have line widths smaller than the quiet regions, implying a longer life-time for the oscillation modes. We suggest that this criterion may be used to forecast the active regions which may trigger CMEs.     

The distribution and utility of sea‐level indicators in Eurasian sub‐Arctic salt marshes (White Sea,Russia)

In support of efforts to reconstruct relative sea level (RSL), we investigated the utility of foraminifera, diatoms and bulk‐sediment geochemistry (δ¹³C, C:N and parameters measured by Rock‐Eval pyrolysis) as sea‐level indicators in Eurasian sub‐Arctic salt marshes. At three salt marshes (<15 km apart) in Dvina Bay (White Sea, Russia), we collected surface sediment samples along transects from subtidal to Taiga forest environments. Foraminifera at all sites formed bipartite assemblages, where elevations below mean high higher water (MHHW) were dominated by Miliammina spp. and elevations between MHHW and the highest occurrence of foraminifera were dominated by Jadammina macrescens and Balticammina pseudomacrescens. Five high‐diversity groups of diatoms were identified and they displayed pronounced variability amongst the study sites. Bulk‐sediment geochemistry recognized two groups (clastic‐dominated environments below MHHW and organic‐rich environments above MHHW). As one group included subtidal elevations and the other included supratidal elevations, we conclude that the measured geochemical parameters are not stand‐alone sea‐level indicators. Core JT2012 captured a regressive sediment succession of clastic, tidal‐flat sediment overlain by salt‐marsh organic silt and freshwater peat. The salt‐marsh sediment accumulated at 2804±52 years before present and preserved foraminifera (Jadammina macrescens and Balticammina pseudomacrescens) with good analogy to modern assemblages indicating that RSL was +2.60±0.47 m at this time. Diatoms confirm that marine influence decreased through time, but the lack of analogy between modern and core assemblages limited their utility as sea‐level indicators. Geochemical parameters also indicate a reduction in marine influence through time. We conclude that RSL reconstructions derived from salt‐marsh sediment preserved beneath Eurasian sub‐Arctic peatlands can provide valuable insight into the spatio‐temporal evolution of the Fennoscandian and Eurasian ice sheets.