Spatial Aspects of Voting in the Dunedin City Council Elections of 1971     

J. Forrest  R. J. Johnston 《New Zealand geographer》1973,29(2):166-181

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Aspects of Observed Gust Factors in Landfalling Tropical Cyclones: Gust Components,Terrain, and Upstream Fetch Effects     

Craig Miller  Juan-Antonio Balderrama  Forrest Masters 《Boundary-Layer Meteorology》2015,155(1):129-155

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RATES OF HEAVE AND SURFACE ROTATION OF PERIGLACIAL FROST BOILS IN THE WHITE MOUNTAINS,CALIFORNIA     

Forrest D. Wilkerson 《自然地理学》2013,34(6):487-502

The White Mountains of California have a cold semi-arid climate that has led to the development of large areas of periglacial patterned ground. Rates of activity vary widely, and no present activity has been noted below 3600 m. Three distinct scales of patterned ground—having average diameters of 3–5 m, 0.5–1.0 m, and 0.1–0.5 m—exist together in a nested fashion at a favorable location at 3914 m. Vertical heave, horizontal displacement, and surface rotation were investigated on landforms of each scale, to determine rates of activity and the spatial and temporal variation of heave. No movement was detected in the largest landforms, but frost boils located in the centers of the larger sorted polygons were highly active. Rates of heave increased dramatically at the beginning of the thaw season, approaching 3.6 mm per day. Dowels were heaved an average of 16.8 cm over ten months. Disks used as surface markers demonstrated exceptional rotational and radial displacement over a nine-month period; 29% of the markers were overturned. The processes responsible for the observed movement in the White Mountains are discussed in relation to processes affecting other alpine environments.  相似文献   

Digital Data-Centric Geography: Implications for Geography's Frontier     

Forrest J. Bowlick  Dawn J. Wright 《The Professional geographer》2013,65(4):687-694

The debate regarding geographic information systems (GIS) as tool, toolbox, or science still lingers in geography departments and among geographers. Analysis of geographic information is a vital component of decision making among business, governments, researchers, and academics. GIS users, geographers and nongeographers alike, use and benefit from problem-solving methods in numerous fields and contexts, making the use of GIS and the core competencies associated with using GIS a topic of intense debate. Complicating this ongoing discussion is the rise of data-centric approaches to research in geography that further expand the capabilities of spatial analysis and add to the expected knowledge of a GIS user and analyst. Building on a panel discussion at the 2016 American Association of Geographers (AAG) annual meeting, as well as informal dialogues on Twitter and other social media platforms that navigate this issue in academics and industry, this article explores how skills in research computing and programming operate in geography and GIS, especially given the rise of data-centric approaches to research in these realms. Some topics, like the costs and benefits of open and closed source software, are familiar from previous discussions in geography and GIS. Others, though, like the reward structures and recognition for computing skills or programming ability, have not been widely considered given the current landscape.  相似文献   

Accelerator measurement of NaI response to medium energy neutrons and application to a Satellite-Borne Spectrometer     

P. P. Dunphy  E. L. Chupp  M. Popecki  D. J. Forrest  D. Lopiano  T. Shima  H. Spinka  G. Glass  G. Burleson  M. Beddo 《Experimental Astronomy》1992,2(4):233-258

We report on the response of a prototype detector to medium energy neutrons. The neutrons were produced by n-p scattering of a neutron beam on a hydrogen target. The measurements provide unique data on the efficiency and response of large NaI scintillators to neutrons in the energy range 36–709 MeV. We apply the results to the high-energy mode of the Gamma-Ray Spectrometer (GRS) on the Solar Maximum Mission satellite by estimating its efficiency for neutron detection. This estimate is compared to earlier Monte Carlo calculations of the GRS efficiency.  相似文献   

The impact of using area-averaged land surface properties —topography, vegetation condition, soil wetness—in calculations of intermediate scale (approximately 10 km) surface-atmosphere heat and moisture fluxes     

Piers J. Sellers  Mark D. Heiser  Forrest G. Hall  Shashi B. Verma  Raymond L. Desjardins  Peter M. Schuepp  J. Ian MacPherson 《Journal of Hydrology》1997,190(3-4):269-301

It is commonly assumed that biophysically based soil-vegetation-atmosphere transfer (SVAT) models are scale-invariant with respect to the initial boundary conditions of topography, vegetation condition and soil moisture. In practice, SVAT models that have been developed and tested at the local scale (a few meters or a few tens of meters) are applied almost unmodified within general circulation models (GCMs) of the atmosphere, which have grid areas of 50–500 km². This study, which draws much of its substantive material from the papers of Sellers et al. (1992c, J. Geophys. Res., 97(D17): 19033–19060) and Sellers et al. (1995, J. Geophys. Res., 100(D12): 25607–25629), explores the validity of doing this. The work makes use of the FIFE-89 data set which was collected over a 2 km × 15 km grassland area in Kansas. The site was characterized by high variability in soil moisture and vegetation condition during the late growing season of 1989. The area also has moderate topography.

The 2 km × 15 km ‘testbed’ area was divided into 68 × 501 pixels of 30 m × 30 m spatial resolution, each of which could be assigned topographic, vegetation condition and soil moisture parameters from satellite and in situ observations gathered in FIFE-89. One or more of these surface fields was area-averaged in a series of simulation runs to determine the impact of using large-area means of these initial or boundary conditions on the area-integrated (aggregated) surface fluxes. The results of the study can be summarized as follows:

1. 1. analyses and some of the simulations indicated that the relationships describing the effects of moderate topography on the surface radiation budget are near-linear and thus largely scale-invariant. The relationships linking the simple ratio vegetation index (SR), the canopy conductance parameter (_F) and the canopy transpiration flux are also near-linear and similarly scale-invariant to first order. Because of this, it appears that simple area-averaging operations can be applied to these fields with relatively little impact on the calculated surface heat flux.

2. 2. The relationships linking surface and root-zone soil wetness to the soil surface and canopy transpiration rates are non-linear. However, simulation results and observations indicate that soil moisture variability decreases significantly as an area dries out, which partially cancels out the effects of these non-linear functions.In conclusion, it appears that simple averages of topographic slope and vegetation parameters can be used to calculate surface energy and heat fluxes over a wide range of spatial scales, from a few meters up to many kilometers at least for grassland sites and areas with moderate topography. Although the relationships between soil moisture and evapotranspiration are non-linear for intermediate soil wetnesses, the dynamics of soil drying act to progressively reduce soil moisture variability and thus the impacts of these non-linearities on the area-averaged surface fluxes. These findings indicate that we may be able to use mean values of topography, vegetation condition and soil moisture to calculate the surface-atmosphere fluxes of energy, heat and moisture at larger length scales, to within an acceptable accuracy for climate modeling work. However, further tests over areas with different vegetation types, soils and more extreme topography are required to improve our confidence in this approach.

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Are Australia’s suburbs swamped by Asians and Muslims? Countering political claims with data     

James Forrest  Ron Johnston  Frank Siciliano  David Manley  Kelvyn Jones 《The Australian geographer》2017,48(4):457-472

Recent decades have seen substantial growth across many developed-world countries of right-wing populist political parties whose policies oppose immigration and multiculturalism as threats to the majority way of life there. These are exemplified in Australia by Pauline Hanson’s One Nation Party, which was successful at elections there at the turn of the twenty-first century and again in 2016. Part of this party’s rhetoric focuses on the geography of immigrant groups in Australia’s cities, with claims that their members live in ghettos. Is that factually correct? Using data from the 2011 Australian census this paper analyses the distribution of Asians and Muslims (the two groups picked out by One Nation and its leader) at four spatial scales within the country’s 11 largest urban areas. It finds no evidence at all of intensive residential segregation of Muslims, and although there are concentrations of Asians—notably in Sydney and Melbourne—most residents claiming Asian ancestry live in neighbourhoods and suburbs where they form a minority (in many cases a small minority) only of the local population.  相似文献   

Aldicarb Studies in Ground Waters from Florida Citrus Groves and Their Relation to Ground—Water Protection     

Forrest E. Dierberg  Chris J. Given 《Ground water》1986,24(1):16-22

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Potential impact on water resources from future volcanic eruptions at Long Valley,Mono County,California, U.S.A.     

R. Forrest Hopson 《Environmental Geology》1991,18(1):49-55

Earthquakes, ground deformation, and increased geothermal activity at Long Valley caldera after mid-1980 suggest the possibility of a volcanic eruption in the near future. An eruption there could have serious consequences for the City of Los Angeles, depending on the magnitude and volume of material ejected because surface water in Mono Basin plus surface and groundwater in Owens Valley accounts for about 80 percent of its water supply. Eruptions of moderate to very large magnitude could impede the supply of water from this area for several days, weeks, or even years by discharging small to large volumes of volcanic ash and causing lahars. Soon after an eruption, water quality would likely be affected by the accumulation of organic debris and microorganisms in surface waters.  相似文献   

Business Trip Activity Patterns     

James Forrest 《New Zealand geographer》1977,33(2):50-59

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