Mineralogical composition of atmospheric airborne particulates

A massive increase in public concern in the last 20 years about the health effects of atmospheric airborne particulates has caused a surge in research activities and has led to ever more stringent government air-quality standards.     

Book reviews

Books Reviewed in this article:
Seismic Velocity Analysis and the Convolutional Model E. A. Robinson (ed.), Reidel, Dordrecht, 1983 320 pp., ISBN 0 939 634637, Dfl. 155, $46 (cloth)
Migration of Geophysical Data E. A. Robinson (ed.), Reidel, Dordrecht, 1983 208 pp., ISBN 0 934 634149, 1130 Dfl.     

Kill the lake? kill the proposal: accommodating First Nations’ environmental values as a first step on the road to wellness

In recent years, a buoyant global market for minerals has led to renewed interest in the mining sector as a means of generating economic growth in resource producing areas of developed nations. The development of new operations, however, raises concerns around the impacts of mining activities on the environment, health and traditional ways of life of Indigenous peoples. Using the proposed expansion of the Kemess mine in northern British Columbia as a case study, this paper examines two First Nations’ perspectives regarding the regulatory process through which environmental values may be validated and protected, and seeks to understand how these First Nations’ environmental values and perceptions of risk are connected to health and well-being. Sixteen key informant interviews were carried out and thematically analyzed through political ecology and environmental justice frameworks. The paper argues that accommodating First Nations’ environmental values and perceptions of risks is a necessary first step to reclaim health and well-being in politically marginalized settings.     

The palaeomagnetism of outcropping oceanic crust on Macquarie Island

Macquarie Island offers a rare opportunity to investigate outcropping ocean crust. In this study, palaeomagnetic samples were collected from 32 sites. After frequency demagnetization, 15 of these sites were found to be stable. Stable sites were from lavas, dykes, and gabbros, representing different depths of formation in the oceanic crust.

A successful bedding correction, assuming a simple model for the oceanic crust, was applied to the directions of magnetization. The former assumed dykes were injected vertically, lavas laid down horizontally, and gabbros layered horizontally. However, the palaeomagnetic poles from the centre and south of the island were not conformable at their 95 percent confidence levels. To remedy this, a structural correction was then applied to sites from the south of the island, where the average strike of dykes is 55° different from that in the centre of the island, which parallels regional seafloor‐spreading anomalies. This correction involved rotation around a vertical axis, which could not be accounted for in a simple bedding correction. When the average strike of the dykes was brought into parallelism with that of the regional seafloor‐spreading anomalies (and presumably that of the fossil spreading ridge), the result was to bring the palaeomagnetic poles from the centre and the south of the island into conformity.

The final pole for Macquarie Island was found to be consistent with a pole of similar age from the Australian Continent. This is consistent with Macquarie Island being formed as part of the Indian plate.

The magnetic properties of the rocks are consistent with seafloor‐spreading anomalies originating from the lavas, with a possible deeper contribution from the gabbros. The dolerite dykes which are palaeomagnetically stable appear to have natural remanent magnetizations (NRM) which are too low to contribute significantly to seafloor‐spreading anomalies.     

Hurricane preparedness and planning in coastal public school districts in the United States

One hundred school districts were surveyed along the Atlantic and Gulf of Mexico coasts from North Carolina to Texas. Nearly all had recent experience with a tropical storm or hurricane and had hurricane plans in place. About half teach hurricane preparedness to students and 85 % train staff members in hurricane preparedness. Sources of information about cyclone threats were the National Hurricane Center (91 %), local television news (74 %), The Weather Channel (67 %), and the internet (67 %). Only 36 % would cancel classes for a hurricane warning but 89 % would cancel classes for a mandatory evacuation. Most districts (75 %) would use schools as storm shelters, and 92 % would use school busses to assist in community evacuations. Districts with a higher percentage of Hispanic population provided hurricane information in Spanish. Larger school districts were less likely to cancel classes in the middle of the day for a storm threat. Districts with higher home values were less likely to use school busses for evacuations, and smaller school districts were less likely to provide schools as storm shelters. There were no other significant associations between hurricane preparedness of the districts and district demographic variables of poverty, percent black, percent Hispanic, population, district size, or median home values.     

The value of bioenergy in low stabilization scenarios: an assessment using REMIND-MAgPIE

This study investigates the use of bioenergy for achieving stringent climate stabilization targets and it analyzes the economic drivers behind the choice of bioenergy technologies. We apply the integrated assessment framework REMIND-MAgPIE to show that bioenergy, particularly if combined with carbon capture and storage (CCS) is a crucial mitigation option with high deployment levels and high technology value. If CCS is available, bioenergy is exclusively used with CCS. We find that the ability of bioenergy to provide negative emissions gives rise to a strong nexus between biomass prices and carbon prices. Ambitious climate policy could result in bioenergy prices of 70 $/GJ (or even 430 $/GJ if bioenergy potential is limited to 100 EJ/year), which indicates a strong demand for bioenergy. For low stabilization scenarios with BECCS availability, we find that the carbon value of biomass tends to exceed its pure energy value. Therefore, the driving factor behind investments into bioenergy conversion capacities for electricity and hydrogen production are the revenues generated from negative emissions, rather than from energy production. However, in REMIND modern bioenergy is predominantly used to produce low-carbon fuels, since the transport sector has significantly fewer low-carbon alternatives to biofuels than the power sector. Since negative emissions increase the amount of permissible emissions from fossil fuels, given a climate target, bioenergy acts as a complement to fossils rather than a substitute. This makes the short-term and long-term deployment of fossil fuels dependent on the long-term availability of BECCS.     

Unpredictable Outcomes in Forestry—Governance Institutions in Practice

Community forest management in the Amazon has been subject to institutional changes because of a shift from government to governance. Although these changes aim to create opportunities for local communities, the effectiveness of new institutions remains arbitrary. In particular, the unpredictability of legislative outcomes—as one of the institutional changes—evokes discussion on how local people respond to new institutions. This article analyzes the effects of forest institutions at the local level. By using the concept of institutional bricolage, the article argues that institutions in practice work differently than intended.     

Assessing the worldwide developments of national spatial data clearinghouses

Many countries have spent considerable resources over the past few years debating optimal national spatial data infrastructures. One of the (main) elements of these infrastructures is the national spatial data clearinghouse, which facilitates access to required spatial data and provides complementary services. With this in mind, in April 2000, 2001, 2002 and December 2000, 2001, 2002, a web survey was carried out to assess systematically the developments of these national clearinghouses worldwide. Regarding the development in the number of implementations, it can be considered a worldwide success. However, of concern are the declining trends in use, management and content. One of the main reasons for these negative trends could be the dissatisfaction of the spatial data community with the functional capability of current clearinghouses. The functional capabilities of clearinghouses should likely be changed from a data-oriented to a user and application-oriented focus. This is in accord with the objectives of the second generation of spatial data infrastructures. The main factors, therefore, that will have positive impacts on developments in this field are the inclusion of web services, stability of funding and creation of user-friendly interfaces.     

The role of sub‐national government and the private sector in future spatial data infrastructures

A Spatial Data Infrastructure (SDI) facilitates and coordinates the exchange and sharing of spatial data between stakeholders in the spatial data community. With this objective in mind, countries throughout the world are developing SDIs to manage and utilize their spatial data assets more effectively. These countries are developing SDIs to assist in various kinds of decision‐making at different levels of government jurisdictions that have an important impact within their national boundaries. However, current research shows that SDI is understood and described differently by stakeholders from different disciplines and different jurisdictional levels. Therefore, in many cases, SDI initiatives remain very much an innovation, even among practitioners. There are still uncertainties regarding the benefits and identities of SDIs, particularly in connection with how they evolve over time to meet user needs. This paper reviews and assesses the development of SDIs throughout the world over the past 15 years and the leadership role of national governments in SDI creation. This assessment is based on the SDI activities of various jurisdictions including Asia‐Pacific, Australia, North America, and Europe, and research into the worldwide effects of spatial information clearing houses. This assessment includes a discussion on emerging trends in SDI development, with particular reference to the increasingly important role played by sub‐national governments and the private sector within the framework of SDI development. The paper concludes with a discussion of the implications for future SDI development, including the delivery of a virtual world that has a particular focus on facilitating decision‐making at a community level within a national context.     

An assessment of hydrothermal alteration in the Santiaguito lava dome complex, Guatemala: implications for dome collapse hazards

A combination of field mapping, geochemistry, and remote sensing methods has been employed to determine the extent of hydrothermal alteration and assess the potential for failure at the Santiaguito lava dome complex, Guatemala. The 90-year-old complex of four lava domes has only experienced relatively small and infrequent dome collapses in the past, which were associated with lava extrusion. However, existing evidence of an active hydrothermal system coupled with intense seasonal precipitation also presents ideal conditions for instability related to weakened clay-rich edifice rocks. Mapping of the Santiaguito dome complex identified structural features related to dome growth dynamics, potential areas of weakness related to erosion, and locations of fumarole fields. X-ray diffraction and backscattered electron images taken with scanning electron microscopy of dacite and ash samples collected from around fumaroles revealed only minor clay films, and little evidence of alteration. Mineral mapping using ASTER and Hyperion satellite images, however, suggest low-temperature (<150 °C) silicic alteration on erosional surfaces of the domes, but not the type of pervasive acid-sulfate alteration implicated in collapses of other altered edifices. To evaluate the possibility of internal alteration, we re-examined existing aqueous geochemical data from dome-fed hot springs. The data indicate significant water–rock interaction, but the Na–Mg–K geoindicator suggests only a short water residence time, and δ¹⁸O/δD ratios show only minor shifts from the meteoric water line with little precipitation of secondary (alteration) minerals. Based on available data, hydrothermal alteration on the dome complex appears to be restricted to surficial deposits of hydrous silica, but the study has highlighted, importantly, that the 1902 eruption crater headwall of Santa María does show more advanced argillic alteration. We also cannot rule out the possibility of advanced alteration within the dome complex interior that is not accessible to the methods used here. It may therefore be prudent to employ geophysical methods to make further assessments in the future.