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We have found 187 datasets for the keyword "mosaïque". You can continue exploring the search results in the list below.
Datasets: 91,529
Contributors: 41
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187 Datasets, Page 1 of 19
High Resolution Digital Elevation Model Mosaic (HRDEM Mosaic) - CanElevation Series
The High Resolution Digital Elevation Model Mosaic provides a unique and continuous representation of the high resolution elevation data available across the country. The High Resolution Digital Elevation Model (HRDEM) product used is derived from airborne LiDAR data (mainly in the south) and satellite images in the north. The mosaic is available for both the Digital Terrain Model (DTM) and the Digital Surface Model (DSM) from web mapping services. It is part of the CanElevation Series created to support the National Elevation Data Strategy implemented by NRCan. This strategy aims to increase Canada's coverage of high-resolution elevation data and increase the accessibility of the products.Unlike the HRDEM product in the same series, which is distributed by acquisition project without integration between projects, the mosaic is created to provide a single, continuous representation of strategy data. The most recent datasets for a given territory are used to generate the mosaic. This mosaic is disseminated through the Data Cube Platform, implemented by NRCan using geospatial big data management technologies. These technologies enable the rapid and efficient visualization of high-resolution geospatial data and allow for the rapid generation of dynamically derived products. The mosaic is available from Web Map Services (WMS), Web Coverage Services (WCS) and SpatioTemporal Asset Catalog (STAC) collections. Accessible data includes the Digital Terrain Model (DTM), the Digital Surface Model (DSM) and derived products such as shaded relief and slope.The mosaic is referenced to the Canadian Height Reference System 2013 (CGVD2013) which is the reference standard for orthometric heights across Canada.Source data for HRDEM datasets used to create the mosaic is acquired through multiple projects with different partners.Collaboration is a key factor to the success of the National Elevation Strategy. Refer to the “Supporting Document” section to access the list of the different partners including links to their respective data.
North American Radar Composite (1 km)
This mosaic is calculated over the North American domain with a horizontal spatial resolution of 1 km. This mosaic therefore includes all the Canadian and American radars available in the network and which can reach a maximum of 180 contributing radars. To better represent precipitation over the different seasons, this mosaic renders in mm/h to represent rain and in cm/h to represent snow. For the two precipitation types (rain and snow), we use two different mathematical relationships to convert the reflectivity by rainfall rates (mm/h rain cm/h for snow). This is a hybrid mosaic from DPQPE (Dual-Pol Quantitative Precipitation Estimation) for S-Band radars. For the US Nexrad radars, ECCC uses the most similar product from the US Meteorological Service (NOAA). This product displays radar reflectivity converted into precipitation rates, using the same formulas as the Canadian radars.
RADARSAT Constellation Mission National Land Mosaic
The Canada Centre for Mapping and Earth Observation (CCMEO) has created a 30m resolution radar mosaic of Canada's landmass from the RADARSAT Constellation Mission (RCM). This product highlights different types of radar interaction with the surface, which can assist the interpretation and study of land cover on a national scale. The national mosaic is made up of 3222 RCM images acquired between August 2023 and February 2024. (Credit: RADARSAT Constellation Mission imagery © Government of Canada [2024]. RADARSAT is an official mark of the CSA.)
Terrestrial Ecozones of Canada
The “Terrestrial Ecozones of Canada” dataset provides representations of ecozones. An ecozone is the top level of the four levels of ecosystems that the National Ecological Framework for Canada defines. The framework divides Canada into 15 terrestrial ecozones that define its ecological mosaic on a sub-continental scale. Ecozones represent an area of the earth’s surface as large and very generalized ecological units. These units are characterized by interactive and adjusting abiotic and biotic factors.
Landsat Circa 2010 Top of Atmosphere Reflectance Mosaic of Canada
Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) sensors were used to generate the circa 2010 Mosaic of Canada at 30 m spatial resolution. All scenes were processed to Standard Terrain Correction Level 1T by the United States Geological Survey (USGS). Further processing performed by the Canada Centre for Remote Sensing included conversion of sensor measurements to top of atmosphere reflectance, cloud and cloud shadow detection, re-projection, selection of best measurements, mosaic generation ,noise removal and quality control. To provide a clear sky measurement for each location in Canada, data from the years 2009, 2010, and 2011 were used, but 2010 was preferentially selected. Bands 3 (0.63-0.69 µm), 4 (0.76-0.90 µm), 5 (1.55-1.75 µm), and 7 (2.08-2.35 µm) are provided in this version as significant atmosphere effects strongly limit the quality of the blue (0.45-0.52 µm) and green (0.52-0.60 µm) bands. Multi-criteria compositing was used for the selection of the most representative pixel. For ETM+ onboard Landsat 7 a scan line malfunction caused missing lines of data in all scenes collected after May 2003. Atmosphere and target variability between scenes cause these lines to have significant radiometric differences in some cases. A Fourier transformation approach was applied to correct this occurrence. This mosaic was developed for land cover and biophysical mapping applications across Canada. Other applications of these data are also possible, but should consider the temporal and spectral limitations of the product. Research to enhance the spatial, spectral and temporal aspects are in development for future versions of moderate resolution products from historical Landsat sensors, Landsat 8, and Sentinel 2 data.
Fenusa pumila
Historical finds of Fenusa pumila
Operophtera brumata
Historical finds of Operophtera brumata
Coleophora serratella
Historical finds of Coleophora serratella
Coleophora laricella
Historical finds of Coleophora laricella
Occurrence and percent cover of the colonial invasive tunicate Didemnum vexillum from near-seafloor drift transect video imagery and high-resolution digital still images in the western Bay of Fundy
Funded under DFO's Marine Conservation Targets Program, this optical imagery benthic survey documents the occurrence and estimated percent cover of the invasive colonial tunicate, Didemnum vexillum in seven drift-camera transects in the 'Head Harbour/West Isles Archipelago/The Passages' Ecologically and Biologically Significant Area (ESBA, ~113km2) in the western Bay of Fundy, New Brunswick, Canada. Occurrence data was derived from the use of high-resolution still images (n=386) taken periodically throughout each transect, and simultaneous continuous high-definition video. Video was divided into 20-second segments (here, we report the start and end location of each segment within a transect) and when D. vexillum was present in a video segment, frequency of occurrence was classified as common (continuous coverage/patches throughout the video segment), occasional (individual colonies of various sizes encountered >5 times throughout the video segment), or rare (small, isolated colonies encountered ≤5 times throughout the video segment). A video segment was deemed unusable and removed from the dataset if there was too much turbidity, or if the camera position was too high off-bottom to reliably image the seafloor. For still images, when D. vexillum was observed in an image, colony percent cover was categorized as >50%, 26-50%, 6-25%, or ≤5% of the images field of view (FOV). Distance travelled and distance between still images (m) was calculated using ArcGIS tools. FOV was estimated by measuring the length and width of a subset of still images and video frame grabs in ImageJ2, using 10-cm lasers for scale. FOV was standardized for each reported altitude, and area sampled (m2) along a continuous video segment was estimated by multiplying the average FOV by the distance travelled in that segment. D. vexillum was found in 44% of the area sampled at depths from 34 to 118m, deeper than previous reports globally of ~80m.Cite this data as: Teed LL, Goodwin C, Lawton P, Lacoursière-Roussel A, Dinning KM (2024) Multiple perspectives on the emergence of the invasive colonial tunicate Didemnum vexillum Kott, 2002 in the western Bay of Fundy, Atlantic Canada. BioInvasions Records 13(3): 713–738, https://doi.org/10.3391/bir.2024.13.3.12
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