Change search
Refine search result
1 - 7 of 7
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Kumar, Rajesh
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Analysing Geospatial Techniques for Land Degradation Studies in Hindu Kush-Himalaya2019In: Environmental Change in the Himalayan Region, Springer, 2019, p. 117-136Chapter in book (Refereed)
  • 2.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Institut für Kartographie, Technische Universität Dresden, Dresden, Germany. Department of Environmental Science, Sharda University, Greater Noida, India.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC ‐ UGR), Armilla, Spain. UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Madrid, Spain.
    Are Slope Streaks Indicative of Global‐Scale Aqueous Processes on Contemporary Mars?2019In: Reviews of geophysics, ISSN 8755-1209, E-ISSN 1944-9208, Vol. 57, no 1, p. 48-77Article in journal (Refereed)
    Abstract [en]

    Slope streaks are prevalent and intriguing dark albedo surface features on contemporary Mars. Slope streaks are readily observed in the equatorial and subequatorial dusty regolith regions with low thermal inertia. They gradually fade over decadal timescales. The proposed mechanisms for their formation vary widely based on several physicochemical and geomorphological explanations. The scientific community is divided in proposing both dry and wet mechanisms for the formation of slope streaks. Here we perform a systematic evaluation of the literature for these wet and dry mechanisms. We discuss the probable constraints on the various proposed mechanisms and provide perspectives on the plausible process driving global‐scale slope streak formation on contemporary Mars. Although per our understanding, a thorough consideration of the global distribution of slope streaks, their morphology and topography, flow characteristics, physicochemical and atmospheric coincidences, and terrestrial analogies weighs more in favor of several wet mechanisms, we acknowledge that such wet mechanisms cannot explain all the reported morphological and terrain variations of slope streaks. Thus, we suggest that explanations considering both dry and wet processes can more holistically describe all the observed morphological variations among slope streaks. We further acknowledge the constraints on the resolutions of remote sensing data and on our understanding of the Martian mineralogy, climate, and atmosphere and recommend continuous investigations in this direction using future remote sensing acquisitions and simulations. In this regard, finding more wet and dry terrestrial analogs for Martian slope streaks and studying them at high spatiotemporal resolutions can greatly improve our understanding.

  • 3.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Discovery of recurring slope lineae candidates in Mawrth Vallis, Mars2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 2040Article in journal (Refereed)
    Abstract [en]

    utside of established RSL regions and further prompt the inclusion of a new geographical region within the RSL candidate group. Our inferences on the RSL candidates are based on several morphological and geophysical evidences and analogies: (i) the dimensions of the RSL candidates are consistent with confirmed mid-latitude RSL; (ii) albedo and thermal inertia values are comparable to those of other mid-latitude RSL sites; and (iii) features are found in a summer season image and on the steep and warmest slopes. These results denote the plausible presence of transient liquid brines close to the previously proposed landing ellipse of the ExoMars rover, rendering this site particularly relevant to the search of life. Further investigations of Mawrth Vallis carried out at higher spatial and temporal resolutions are needed to identify more of such features at local scales to maximize the scientific return from the future Mars rovers, to prevent probable biological contamination during rover operations, to evade damage to rover components as brines can be highly corrosive, and to quantify the ability of the regolith at mid-latitudes to capture atmospheric water which is relevant for in-situ-resource utilization.

  • 4.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, Granada, Spain.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain.
    Distribution and Morphologies of Transverse Aeolian Ridges in ExoMars 2020 Rover Landing Site2019In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, no 8, article id 912Article in journal (Refereed)
    Abstract [en]

    Aeolian processes are believed to play a major role in the landscape evolution of Mars. Investigations on Martian aeolian landforms such as ripples, transverse aeolian ridges (TARs), and dunes, and aeolian sediment flux measurements are important to enhance our understanding of past and present wind regimes, the ongoing dust cycle, landscape evolution, and geochemistry. These aeolian bedforms are often comprised of loose sand and sharply undulating topography and thus pose a threat to mobility and maneuvers of Mars rovers. Here we present a first-hand account of the distribution, morphologies, and morphometrics of TARs in Oxia Planum, the recently selected ExoMars 2020 Rover landing site. The gridded mapping was performed for contiguous stretches of TARs within all the landing ellipses using 57 sub-meter high resolution imaging science experiment (HiRISE) scenes. We also provide the morphological descriptions for all types of TARs present within the landing ellipses. We use HiRISE digital terrain models (DTMs) along with the images to derive morphometric information for TARs in Oxia Planum. In general, the average areal TAR coverage was found to be 5.4% (±4.9% standard deviation), increasing from west to east within the landing ellipses. We report the average TAR morphometrics in the form of crest–ridge width (131.1 ± 106.2 m), down-wind TAR length (17.6 ± 10.1 m), wavelength (37.3 ± 11.6 m), plan view aspect ratio (7.1 ± 2.3), inter-bedform spacing (2.1 ± 1.1), slope (10.6° ± 6.1°), predominant orientations (NE-SW and E-W), and height (1.2 ± 0.8 m). While simple TARs are predominant, we report other TAR morphologies such as forked TAR, wavy TAR with associated smaller secondary ripples, barchan-like TAR, networked TAR, and mini-TARs from the region. Our results can help in planning the rover traverses in terms of both safe passage and scientific returns favoring aeolian research, particularly improving our understanding of TARs.

  • 5.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martin-Torres, Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano Mier, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Ramírez Luque, Juan Antonio
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    UAV Imaging of a Martian Brine Analogue Environment in a Fluvio-Aeolian Setting2019In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 11, no 18, article id 2104Article in journal (Refereed)
    Abstract [en]

    Understanding extraterrestrial environments and landforms through remote sensing and terrestrial analogy has gained momentum in recent years due to advances in remote sensing platforms, sensors, and computing efficiency. The seasonal brines of the largest salt plateau on Earth in Salar de Uyuni (Bolivian Altiplano) have been inadequately studied for their localized hydrodynamics and the regolith volume transport across the freshwater-brine mixing zones. These brines have recently been projected as a new analogue site for the proposed Martian brines, such as recurring slope lineae (RSL) and slope streaks. The Martian brines have been postulated to be the result of ongoing deliquescence-based salt-hydrology processes on contemporary Mars, similar to the studied Salar de Uyuni brines. As part of a field-site campaign during the cold and dry season in the latter half of August 2017, we deployed an unmanned aerial vehicle (UAV) at two sites of the Salar de Uyuni to perform detailed terrain mapping and geomorphometry. We generated high-resolution (2 cm/pixel) photogrammetric digital elevation models (DEMs) for observing and quantifying short-term terrain changes within the brines and their surroundings. The achieved co-registration for the temporal DEMs was considerably high, from which precise inferences regarding the terrain dynamics were derived. The observed average rate of bottom surface elevation change for brines was ~1.02 mm/day, with localized signs of erosion and deposition. Additionally, we observed short-term changes in the adjacent geomorphology and salt cracks. We conclude that the transferred regolith volume via such brines can be extremely low, well within the resolution limits of the remote sensors that are currently orbiting Mars, thereby making it difficult to resolve the topographic relief and terrain perturbations that are produced by such flows on Mars. Thus, the absence of observable erosion and deposition features within or around most of the proposed Martian RSL and slope streaks cannot be used to dismiss the possibility of fluidized flow within these features

  • 6.
    Bhardwaj, Anshuman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Sam, Lydia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Martín-Torres, F. Javier
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Zorzano, María-Paz
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Revisiting enigmatic Martian slope streaks2019In: Earth Space and Science News - Editors Vox, Vol. 100Article in journal (Other academic)
  • 7.
    Sam, Lydia
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Kumar, Rajesh
    Bhardwaj, Anshuman
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Climate and Remotely Sensed Markers of Glacier Changes in the Himalaya2019In: Environmental Change in the Himalayan Region, Springer, 2019, p. 65-88Chapter in book (Refereed)
    Abstract [en]

    The study of past and future climatic variations in the Hindu Kush–Himalayan (HKH) region is a well-documented topic of scientific research. Recent studies have highlighted the significantly higher rates of warming in the HKH region compared to the global average. The HKH region has the largest reserves of glacial ice outside the poles. These glaciers are predominantly known to be sensitive indicators of changing regional and global climate. The large geographical extent, high elevation and perennial inclemency in weather conditions project remote sensing as the only viable option to study glacial characteristics periodically on a regional scale. The present chapter starts with a review of significant studies to assess the extent of climate change in the HKH. Climate-sensitive glacial markers which can be studied using remote sensing are identified. The chapter focuses on the key markers such as changes in glacier extents, glacier facies and supraglacial debris, and mass balance and thickness. The chapter examines these markers separately with respect to changing climate through recent remote sensing-based studies. It provides an overview of recent studies which deal with regional scale glaciological monitoring and assessment. The conclusive section of the chapter suggests the future role of remote sensing applications in studying these markers of climate change. The chapter uses recent studies to highlight key aspects that should be kept in perspective while undertaking remotely sensed glacial assessments.

1 - 7 of 7
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf