D. L. Marcotte’s research while affiliated with National Research Council Canada and other places

... Simulations allowed identification of stable features of the inverted fields. Shamsipour et al. (2010b) explored the adaptation of the method to gravity gradients. In this article, we present the 3D inversion of airborne gravity gradient data constrained by geological or physical properties of rocks, using stochastic methods, a practical extension of the work of Shamsipour et al. (2010a, 2010b). ...

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3D unconstrained and geologically constrained stochastic inversion of airborne vertical gravity gradient data

... Conversely, measurements of the vertical and horizontal magnetic gradients have significant advantages over total magnetic field surveys with single-sensor magnetometry. These include the reductions in regional magnetic gradients, the elimination of short-term diurnal fluctuations, and the attenuation of longer wavelength anomalies due to deeper magnetic sources; thus, smaller-scale shallow anomalies are enhanced by removing the masking effects of longer wavelength anomalies (Young and Droege [42]; Marcotte et al. [78]), improving the resolution of minor anomalies, and resolving complex anomalies (Cowan et al. [79]). Another advantage of using a gradiometer is that the transient signals of the Earth's magnetic field are the same for the two sensors, so it completely cancels out any differences in signals that are unaffected by diurnal variations (Sharma [60]; Mussett and Khan [68]; Milsom and Eriksen [76]; Cowan et al. [79]). ...

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Integrated Shallow Geophysical Surveys at Two Caddo Period Archaeological Sites within the Limits of a Water Reservoir in Northeastern Texas, USA

... Mixed-phase clouds (MPCs) are frequently occurring in the Arctic: they can persist over several days under different meteorological conditions (e.g., Shupe and Intrieri, 2004;Morrison et al., 2012;Mioche et al., 2015). These clouds are generally composed of one or several distinct stratiform layers consisting of supercooled water droplets embedded near the top of an ice cloud (Curry et al., 2000;Korolev et al., 2003;Shupe et al., 2011). Single-layer stratocumulus MPCs have been extensively studied in the western and European Arctic (Shupe et al., 2006;Gayet et al., 2009;McFarquhar et al., 2011;Morrison et al., 2012;Lloyd et al., 2015;Mioche et al., 2017;Achtert et al., 2020;Järvinen et al., 2023). ...

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Arctic mixed-phase clouds simulated by the WRF model: Comparisons with ACLOUD radar and in situ airborne observations and sensitivity of microphysics properties

... The National Research Council of Canada's Convair-580 research aircraft is a twinengine pressurized aircraft that was modified to conduct investigations of atmospheric phenomena and is capable of carrying up to a dozen scientists. The aircraft has an extensive history of collecting data for aircraft icing studies (Cober et al. 1995;Isaac et al. 1999Isaac et al. , 2001Isaac et al. , 2005Williams et al. 2015;Minder et al. 2023). The Convair-580 carried an array of navigational, cloud physics, and atmospheric chemistry instrumentation during the ICICLE campaign. ...

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Airborne Observations of Highly Variable and Complex Freezing Drizzle and Mixed-Phase Environments

... Methods that enhance trends are particularly important, and several techniques have been put forward to enhance trends in aeromagnetic maps. Using measured gradients can dramatically improve the trend of sharp features and/or linear structures at an acute angle with respect to flight lines (Marcotte et al., 1990;Cowan et al., 1995;McMullan et al., 1995;Hardwick, 1999;O'Connell et al., 2005;Reford, 2006). Yunxuan (1993) uses a band-limited Radon transform (RT) as applied to synthetic gravity maps to remove boudinage artifacts, but the technique remains limited to only one trend direction. ...

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Trend enhancement in aeromagnetic maps using constrained coherence-enhancing diffusion filtering

... No clear pattern of sea-floor spreading anomalies has yet been observed, partly because data distribution and quality are insufficient. An aeromagnetic survey program has been initiated over the Canadian polar continental margins (Nelson et al. 1991), but more data are needed on a regional scale. Given present and foreseeable technology, a regional airborne mapping program covering the entire Amerasian Basin appears to be an effective means to acquire that data. ...

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Reading the stripes: offshore discoveries in plate tectonics with examples from eastern Canada

... There are several studies presenting approaches to explain the development of precipitating freezing drizzle. The interested reader is referred for example to Cober et al. (1996) or Korolev and Isaac (2000). Even if the super-cooled drops are not large enough to precipitate, they may pose a significant threat for aircraft crossing the cloud, as they freeze on contact as well. ...

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WHITE - Winter hazards in terminal environment: An automated nowcasting system for Munich Airport

... These yields detailed data about shallow geological characteristics, which remain unaltered by diurnal fluctuations and the magnetic field background of the region. As an illustration of the gradient tensor measurement's power, the Canadian Geological Survey initiated an aeromagnetic gradiometer program in Canada, developing short baseline aeromagnetic gradiometers back in 1975 [30][31][32]. ...

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Gradiometry Processing Techniques for Large-Scale of Aeromagnetic Data for Structural and Mining Implications: The Case Study of Bou Azzer Inlier, Central Anti-Atlas, Morocco

... (3). To determine C β , yawing maneuvers were used, which are commonly applied for such calibration (e.g., Bögel and Baumann, 1991;Drüe and Heinemann, 2013;Mallaun et al., 2015;Williams and Marcotte, 2000). In a first step, the wind vector is calculated for a yawing maneuver. ...

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The ASK-16 motorized glider: an airborne eddy covariance platform to measure turbulence, energy, and matter fluxes

... There are many applications where FSSP is used especially when droplet spectra are required. Cober et al. (1995Cober et al. ( , 1999, based on works of Ashenden and Marwitz (1998) and Miller et al. (1998), give the case of aircraft icing characterizations, as an example of FSSP use. Cober and Isaac (2012) highlighted the interest of FSSP for the measurements of the super large droplet characterisation. ...

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Some effects of ice crystals on the FSSP measurements in mixed phase clouds