“Building glass refrigerators in the desert”: discourses of urban sustainability and nation building in Qatar

Planners around the Arab Gulf states are increasingly drawing on narratives about “urban sustainability,” despite the fact that the explosive growth of urban centers in the Arabian desert largely defies the logic of sustainability. In this article, I consider how and with what effect these narratives have been deployed by various actors in Doha, Qatar. Eschewing a simple economistic reading, I highlight political geographic context and analyze how actors mobilize and rework these discourses. Drawing on mixed-methods fieldwork in Fall 2013, I illustrate how sustainability narratives are mobilized together with nationalist tropes about modernizing Qatar and building up the country’s international prestige, while preserving local traditions and culture through the built environment. With a focus on recent efforts to green Doha, this analysis sheds light on the disciplining function of nationalist discourses in the production and constitution of what it means to label development practices “green” in contemporary Qatar.     

EARLY HOLOCENE CONDITIONS AT THE WESTERN MARGIN OF CAPE COD BAY

A paleoenvironmental model is proposed for the western shoreline of Cape Cod Bay, Massachusetts, from about 9,000 through 5,500 years B.P. Central to this reconstruction is the integration and correlation of the glacial sediments, radiometric chronology and pollen stratigraphy of an exposed peat deposit located near Nameloc Heights, Plymouth, Massachusetts. Four Carbon-14 dates provide a chronology and suggest an average rate of peat accumulation of about 6 cm/100 years from 8,800 through 7,400 years B.P., decreasing to 3 cm/100 years from 7,400 to 5,500 years B.P. This sequence of radiometric dates provides a temporal framework within which the pollen taxa of the peat deposit can be correlated to the established floristic zones of the southern New England region.     

SHORELINE CHANGE AT THOMPSON ISLAND,BOSTON HARBOR,MASSACHUSETTS, 1938-1977

A photogrammetric and sediment analysis is presented to illustrate the relationship between beach erosion and seacliff recession on Thompson Island, Boston Harbor, Massachusetts. Aerial photographs taken in 1938, 1952, 1963, and 1977 were measured to determine rates of shoreline change around the island. The 39-year average rate of beach erosion is 0.3 m/yr ± 2% with an average rate of cliff recession at 0.2 m/yr ± 2%. Rates of beach erosion between six orientations that reflect principal wave approach to the island were not found to be significantly different (0.05) for the 39-year period. The rank order correlation between beach erosion and cliff recession for these six orientations was moderately well correlated (0.63). To determine possible controls of cliff erosion, 58 sediment samples were collected from glacial cliffs along the shoreline. The textural composition was determined, and then tested with discriminant function analysis. Partial correlation analysis between beach erosion and cliff recession holding a surrogate for sediment size constant improved the rank order from 0.63 to 0.84. The results indicate that coarser-grained cliffs recede at faster rates, but with less erosion occurring on adjacent beaches. Alternatively, finer-grained cliffs recede at slower rates, but with greater erosion occurring on adjacent beaches.     

EVOLUTIONARY CONVERGENCE OR PHENOTYPIC PLASTICITY? RESPONSES TO SUMMER RAIN BY CALIFORNIA CHAPARRAL

An unusual summer rain upon southern California chaparral was followed by rapid water uptake, growth, flowering, and fruiting sequences similar to normal spring growth flushes, owing to genetically fixed traits associated with shrub physiology and reproductive biology. This response to summer rain demonstrates the advantage for shrubs to be flexible in the initiation and duration of growth in an unpredictable environment. Evergreen sclerophyllous chaparral is generally interpreted as a product of evolutionary convergence in which environmental stresses posed by Mediterranean climate limit adaptive evolutionary strategies. Phenological records of chaparral taxa or closely related congeners living in summer rain climates in Arizona, central and southern Baja California, and mainland Mexico, along with fossil evidence, suggest that shrubs evolved in response to a somewhat different Tertiary climate; development of the ecosystem reflects the geographic expansion of similar adaptive forms into the newly developing Mediterranean climate, or migrational convergence. Interpretation of evidence in sprouting behavior and reproductive biology suggests that most evolution in California chaparral derives from selective pressures of burning rather than adaptation to drought.     

DRIFT VOLUME IN THE SOUTHERN PENINSULA OF MICHIGAN—A PRODIGIOUS PLEISTOCENE ENDOWMENT

Michigan's Southern Peninsula is by far the largest drift repository in the Great Lakes Area. Thickness of the glacial sediments averages 85 m and volume, previously unknown, exceeds 9300 km³. The distribution, however, is very uneven, as is the underlying bedrock surface. These variations and known surface characteristics provide a basis for the first qualitative and quantitative identification of distinct drift realms. Even the smallest of the eight realms contains about 35% more drift than the better known Kettle Moraine tract of Wisconsin, which encompasses 50% more area. Comparative analysis within the peninsula shows that Pleistocene glaciation completely transformed the topography to the north, whereas the southern half has palimpsest relationships with subcropping formations. [Key words: drift, drift volume, Michigan, Great Lakes, Pleistocene.]     

BEAVER-POND SEQUENCE MORPHOLOGY AND SEDIMENTATION IN NORTHWESTERN MONTANA

Two adjacent beaver-pond sequences of seven ponds each were examined along the eastern boundary of Glacier National Park, Montana, to determine spatial patterns and amounts of sedimentation, both within individual ponds and along pond sequences. Dams and their associated ponds were categorized into two age groups, young versus old, based on dam morphology and surface vegetation. Old ponds contained significantly more sediment than did young ponds. However, hypothesized patterns of downstream reductions in coarse-grained sediment, both within a pond and along a sequence, were not observed, nor were there any discernible patterns in sediment texture across ponds. [Key words: beaver pond, sedimentation, Rocky Mountains, Montana.]     

Mitigating the impact of ionospheric cycle slips in GNSS observations

Processing of data from global navigation satellite systems (GNSS), such as GPS, GLONASS and Galileo, can be considerably impeded by disturbances in the ionosphere. Cycle-slip detection and correction thus becomes a crucial component of robust software. Still, dealing with ionospheric cycle slips is not trivial due to scintillation effects in both the phase and the amplitude of the signals. In this contribution, a geometry-based approach with rigorous handling of the ionosphere is presented. A detailed analysis of the cycle-slip correction process is also tackled by examining its dependence on phase and code noise, non-dispersive effects and, of course, the ionosphere. The importance of stochastic modeling in validating the integer cycle-slip candidates is emphasized and illustrated through simulations. By examining the relationship between ionospheric bias and ionospheric constraint, it is shown that there is a limit in the magnitude of ionospheric delay variation that can be handled by the cycle-slip correction process. Those concepts are applied to GNSS data collected by stations in northern Canada, and show that enhanced cycle-slip detection can lead to decimeter-level improvements in the accuracy of kinematic PPP solutions with a 30-s sampling interval. Cycle-slip correction associated with ionospheric delay variations exceeding 50 cm is also demonstrated, although there are risks with such a procedure and these are pointed out.     

Statewide groundwater‐vulnerability assessment in nebraska using the drastic/GIS model

The paper summarizes a technique for implementing the “DRASTIC” groundwater‐vulnerability model within the context of an automated raster‐based geographic information system. Discussion focuses on a methodological development and a statewide project completed recently in Nebraska. The final products, a comprehensive flow chart illustrating procedures and a map of calculated potential pollution hazard, are presented. The methodology can be executed successfully with minimal training and experience. Areas of Nebraska considered vulnerable to groundwater pollution are identified.     

Winter Arctic Amplification at the synoptic timescale, 1979–2018, its regional variation and response to tropical and extratropical variability

We investigate winter Arctic Amplification (AA) on synoptic timescales and at regional scales using a daily version of the Arctic Amplification Index (AAI) and examine causes on a synoptic scale. The persistence, frequency and intensity of high AAI events show significant increases over the Arctic. Similarly, low AAI events are decreasing in frequency, persistence and intensity. In both cases, there are regional variations in these trends, in terms of significance and timing. Significant trends in increasing persistence, frequency and intensity of high AAI events in winter are concentrated in the period 2000–2009, with few significant trends before and after this. There are some decreases in sea-ice concentration in response to synoptic-scale AA events and these AA events can contribute to the decadal trends in AA found in other studies. A sectoral analysis of the Arctic indicates that in the Beaufort–Chukchi and East Siberian–Laptev Seas, synoptic scale high AAI events can be driven by tropical teleconnections while in other Arctic sectors, it is the intrusion of moisture-transporting synoptic cyclones into the Arctic that is most important in synoptic-scale AA. The presence of Rossby wave breaking during high AAI events is indicative of forcing from lower latitudes, modulated by variations in the jet stream. An important conclusion is that the increased persistence, frequency and intensity of synoptic-scale high AAI events make significant contributions to the interannual trend in AA.