scholarly journals Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery

2021 ◽  
Author(s):  
S Baumann ◽  
Brian Anderson ◽  
T Chinn ◽  
A MacKintosh ◽  
C Collier ◽  
...  
Keyword(s):  
New Zealand ◽  
Satellite Imagery ◽  
Ratio Method ◽  
Landsat 8 ◽  
Band Ratio ◽  
Maximum Likelihood Classification ◽  
The North ◽  
Area Reduction ◽  
Covered Area ◽  
Glacier Ice

Copyright © The Author(s), 2020. Published by Cambridge University Press. The only complete inventory of New Zealand glaciers was based on aerial photography starting in 1978. While there have been partial updates using 2002 and 2009 satellite data, most glaciers are still represented by the 1978 outlines in contemporary global glacier databases. The objective of this project is to establish an updated glacier inventory for New Zealand. We have used Landsat 8 OLI satellite imagery from February and March 2016 for delineating clean glaciers using a semi-Automatic band ratio method and debris-covered glaciers using a maximum likelihood classification. The outlines have been checked against Sentinel-2 MSI data, which have a higher resolution. Manual post processing was necessary due to misclassifications (e.g. lakes, clouds), mapping in shadowed areas, and combining the clean and debris-covered parts into single glaciers. New Zealand glaciers cover an area of 794 ± 34 km2 in 2016 with a debris-covered area of 10%. Of the 2918 glaciers, seven glaciers are >10 km2 while 71% is <0.1 km2. The debris cover on those largest glaciers is >40%. Only 15 glaciers are located on the North Island. For a selection of glaciers, we were able to calculate the area reduction between the 1978 and 2016 inventories.

scholarly journals Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery

2020 ◽  
pp. 1-14
Author(s):  
Sabine Baumann ◽  
Brian Anderson ◽  
Trevor Chinn ◽  
Andrew Mackintosh ◽  
Catherine Collier ◽  
...  
Keyword(s):  
New Zealand ◽  
Satellite Imagery ◽  
Ratio Method ◽  
Landsat 8 ◽  
Band Ratio ◽  
Maximum Likelihood Classification ◽  
The North ◽  
Area Reduction ◽  
Covered Area ◽  
Glacier Ice

Abstract The only complete inventory of New Zealand glaciers was based on aerial photography starting in 1978. While there have been partial updates using 2002 and 2009 satellite data, most glaciers are still represented by the 1978 outlines in contemporary global glacier databases. The objective of this project is to establish an updated glacier inventory for New Zealand. We have used Landsat 8 OLI satellite imagery from February and March 2016 for delineating clean glaciers using a semi-automatic band ratio method and debris-covered glaciers using a maximum likelihood classification. The outlines have been checked against Sentinel-2 MSI data, which have a higher resolution. Manual post processing was necessary due to misclassifications (e.g. lakes, clouds), mapping in shadowed areas, and combining the clean and debris-covered parts into single glaciers. New Zealand glaciers cover an area of 794 ± 34 km2 in 2016 with a debris-covered area of 10%. Of the 2918 glaciers, seven glaciers are >10 km2 while 71% is <0.1 km2. The debris cover on those largest glaciers is >40%. Only 15 glaciers are located on the North Island. For a selection of glaciers, we were able to calculate the area reduction between the 1978 and 2016 inventories.

scholarly journals Updated inventory of glacier ice in New Zealand based on 2016 satellite imagery

2021 ◽  
Author(s):  
S Baumann ◽  
Brian Anderson ◽  
T Chinn ◽  
A MacKintosh ◽  
C Collier ◽  
...  
Keyword(s):  
New Zealand ◽  
Satellite Imagery ◽  
Ratio Method ◽  
Landsat 8 ◽  
Band Ratio ◽  
Maximum Likelihood Classification ◽  
The North ◽  
Area Reduction ◽  
Covered Area ◽  
Glacier Ice

Copyright © The Author(s), 2020. Published by Cambridge University Press. The only complete inventory of New Zealand glaciers was based on aerial photography starting in 1978. While there have been partial updates using 2002 and 2009 satellite data, most glaciers are still represented by the 1978 outlines in contemporary global glacier databases. The objective of this project is to establish an updated glacier inventory for New Zealand. We have used Landsat 8 OLI satellite imagery from February and March 2016 for delineating clean glaciers using a semi-Automatic band ratio method and debris-covered glaciers using a maximum likelihood classification. The outlines have been checked against Sentinel-2 MSI data, which have a higher resolution. Manual post processing was necessary due to misclassifications (e.g. lakes, clouds), mapping in shadowed areas, and combining the clean and debris-covered parts into single glaciers. New Zealand glaciers cover an area of 794 ± 34 km2 in 2016 with a debris-covered area of 10%. Of the 2918 glaciers, seven glaciers are >10 km2 while 71% is <0.1 km2. The debris cover on those largest glaciers is >40%. Only 15 glaciers are located on the North Island. For a selection of glaciers, we were able to calculate the area reduction between the 1978 and 2016 inventories.

scholarly journals Aeromagnetic and spectral expressions of rare earth element deposits in Gallinas Mountains area, Central New Mexico, USA

2018 ◽  
Vol 6 (4) ◽  
pp. T937-T949
Author(s):  
Mo Li ◽  
Xiaobing Zhou ◽  
Christopher H. Gammons ◽  
Mohamed Khalil ◽  
Marvin Speece
Keyword(s):  
New Mexico ◽  
Iron Oxides ◽  
Volcanic Rocks ◽  
Ratio Method ◽  
Landsat 8 ◽  
Band Ratio ◽  
Ratio Imaging ◽  
Ore Distribution ◽  
Surface Mineral ◽  
Host Rocks

The Gallinas Mountains, located at the junction of Lincoln and Torrance Counties, New Mexico, USA, are a series of alkaline volcanic rocks intruded into Permian sedimentary rocks. The Gallinas Mountains area hosts fluorite and copper as veins containing bastnäsite, whereas deposits of iron skarns and iron replacement are in the area as well. These deposits produce iron. In this study, the multispectral band-ratio method is used for surface mineral recognition, whereas 2D subsurface structure inversion modeling was applied to explore the depth extent of the magnetic ore distribution from aeromagnetic data. Bastnäsite has higher magnetic susceptibility (0.009 SI) than the host rocks and surrounding sedimentary rock. The bastnäsite and iron oxides (magnetite + hematite) can contribute to a positive aeromagnetic anomaly. Results indicate that (1) the positive magnetic anomaly observed at Gallinas Mountains area can be accounted for by a mixture of bastnäsite and iron oxides at a depth of approximately 400 m and a thickness of approximately 13–15 m. The surface of this area is dominated by the hydrothermal alteration associated with iron oxides over the trachyte intrusions as detected by Landsat 8 band-ratio imaging.

scholarly journals Uma abordagem metodológica de Sensoriamento Remoto para o monitoramento da contaminação do rio Paraopeba pós-desastre de Brumadinho-MG

2021 ◽  
Vol 43 ◽  
pp. e36
Author(s):  
Neison Cabral Ferreira Freire ◽  
Admilson Da Penha Pacheco ◽  
Vinícius D'Lucas Bezerra Queiroz
Keyword(s):  
Remote Sensing ◽  
Spectral Band ◽  
Ratio Method ◽  
Landsat 8 ◽  
Surface Reflectance ◽  
Band Ratio ◽  
Hydrographic Basin ◽  
Search Area ◽  
Brazilian History ◽  
Sentinel 2

The following article aims to present and discuss the monitoring, through Remote Sensing, of the dirt displacement caused by the collapse of the Córrego do Feijão’s dam I of mining waste, which occurred on January 25, 2019, in the rural area of Brumadinho, a city located in the state of Minas Gerais, Brazil. This event is considered one of the greatest technoindustrial disasters in Brazilian history, placing in danger one of the largest hydrographic basin in Brazil: the São Francisco river basin. The search area comprises from where the sludge mud got in contact with the Paraopeba’s right bank to its mouth into the Três Marias Dam, adding up to approximately 315 km. For this monitoring the spectral band ratio method was utilized,  using images from the sensors MSI/Sentinel-2 and OLI/Landsat-8 captured at different dates, employing standardization of means and variances to harmonize the range of the surface reflectance values in each image.

Characterising the 2002 toxic Karenia concordia (Dinophyceae) outbreak and its development using satellite imagery on the north-eastern coast of New Zealand

Harmful Algae ◽  
2008 ◽  
Vol 7 (4) ◽  
pp. 532-544 ◽  
Author(s):  
F. Hoe Chang ◽  
Michael J. Uddstrom ◽  
Matt H. Pinkerton ◽  
Ken M. Richardson
Keyword(s):  
New Zealand ◽  
Satellite Imagery ◽  
Eastern Coast ◽  
The North ◽  
North Eastern

scholarly journals Snow Cover Area Detection using NDSI and Band Ratio Method

2020 ◽  
Vol 9 (7S) ◽  
pp. 66-70
Keyword(s):  
Snow Cover ◽  
Near Infrared ◽  
Ratio Method ◽  
Automated Classification ◽  
Gis Technology ◽  
Infrared Band ◽  
Snow Cover Area ◽  
Band Ratio ◽  
Snow Covered Area ◽  
Covered Area

Glaciers are a main source of water during summer in Himalayan areas. Corresponding to the historical studies, glacier is directly affected by climate change. It is important to identify change in snow cover area (Glacier area) to identify change in glacier. Remote sensing and GIS technology are used to monitor Snow covered area. This paper focuses on Sentinel-2B data of trisul glacier which is a part of Indian Himalayas to identify glacier. These multispectral images were extracted from USGS Earth Explorer. The sentinel-2B data are processed using Semi automated Classification Plugin (SCP) of QGIS tool. Snow covered area is identified by using two automated methods: Normalized Difference Snow Index (NDSI) and Band Ratio. For NDSI reflectance of visible, shortwave band is used. For Band Ratio reflectance of near infrared, shortwave infrared band is used. It is challenging to detect snow covered area from the satellite as snow covered area and cloud area have same white colure i.e. same reflectance. In this paper, represents experiments on two methods for snow area extraction on satelliteimages.

scholarly journals Paläoklimatologische Eindrücke aus Neuseeland

1965 ◽  
Vol 16 (1) ◽  
pp. 226-238
Author(s):  
Martin Schwarzbach
Keyword(s):  
New Zealand ◽  
Windward Side ◽  
Western Coast ◽  
Volcanic Area ◽  
The North ◽  
Long Time ◽  
Glacier Ice ◽  
Climatic History ◽  
The Difference ◽  
Wet Climate

Abstract. Some observations and remarks about the climate and paleoclimate of New Zealand, founded on journeys and the work of New Zealandic geologists. Some peculiarities of the climate (fig. 1). New Zealand has a relatively cool and wet climate (similar to Tasmania at the present). There is a very conspicious difference between the very humid windward side and the arid lee-side of the Southern Alps (also in the vegetation, fig. 2). „Edaphically caused deserts" begin to develop in the volcanic area of the North Island (fig. 3). The glaciers on the western coast of New Zealand (fig. 4), especially Franz Josef and Fox Glaciers, are impressive examples for the coexistence of lush, nearly subtropical rainforests (with tree-ferns) with glacier ice (figs. 6, 8). Therefore they are especially important for paleoclimatologists and for the interpretation of climatic indicators. Both glaciers have their tongues near the sea, nearly 2000 mts. below snow-line. Their recession (fig. 7) was 1200 and 1800 m respectively in 21 years. The cause for the low position of the tongues is to bee seen in high precipitation in connexion with the altitude and steepness of the mountains. Climatic history of New Zealand. The Quaternary is not treated; it only is referred to the influence of recent tectonic movements on the terraces. — The climate of the Tertiary was temperate to subtropical and humid. Maximal temperatures did not occur (as in Europe and North America) in the older, but (as in Australia) in the middle Tertiary (fig. 9). The author tries to explain this difference by the combination of 2 curves (fig. 10): one is the curve of changing latitude, caused by drift, the other is the general trend of the decline of temperature in Tertiary time. Because Australia obviously moved towards the equator, but Europe (if at all) towards the pole, the resulting curve is different in both continents. — Also the Mesozoic climate was neither tropical nor arid. Perhaps the Permian was a little warmer than in Australia. Compared with Australia, the climatic history is distinctly different. Australia changed from a polar climate to a subtropical and tropical one since the Carboniferous-Permian period, but New Zealand seems to have remained more or less in the same climatic zone during this long time. We don't yet know whether the difference between New Zealand and Australia is only apparent (caused by gaps in our knowledge), or is caused by an independent northward drift of both regions (Australia quickly, New Zealand more slowly).

scholarly journals Glacier shrinkage in the Alps continues unabated as revealed by a new glacier inventory from Sentinel-2

2020 ◽  
Vol 12 (3) ◽  
pp. 1805-1821 ◽  
Author(s):  
Frank Paul ◽  
Philipp Rastner ◽  
Roberto Sergio Azzoni ◽  
Guglielmina Diolaiuti ◽  
Davide Fugazza ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Uncertainty Assessment ◽  
Ratio Method ◽  
Band Ratio ◽  
Glacier Inventory ◽  
Glacier Shrinkage ◽  
Run Off ◽  
Glacier Ice ◽  
The Alps ◽  
Sentinel 2

Abstract. The ongoing glacier shrinkage in the Alps requires frequent updates of glacier outlines to provide an accurate database for monitoring, modelling purposes (e.g. determination of run-off, mass balance, or future glacier extent), and other applications. With the launch of the first Sentinel-2 (S2) satellite in 2015, it became possible to create a consistent, Alpine-wide glacier inventory with an unprecedented spatial resolution of 10 m. The first S2 images from August 2015 already provided excellent mapping conditions for most glacierized regions in the Alps and were used as a base for the compilation of a new Alpine-wide glacier inventory in a collaborative team effort. In all countries, glacier outlines from the latest national inventories have been used as a guide to compile an update consistent with the respective previous interpretation. The automated mapping of clean glacier ice was straightforward using the band ratio method, but the numerous debris-covered glaciers required intense manual editing. Cloud cover over many glaciers in Italy required also including S2 scenes from 2016. The outline uncertainty was determined with digitizing of 14 glaciers several times by all participants. Topographic information for all glaciers was obtained from the ALOS AW3D30 digital elevation model (DEM). Overall, we derived a total glacier area of 1806±60 km2 when considering 4395 glaciers >0.01 km2. This is 14 % (−1.2 % a−1) less than the 2100 km2 derived from Landsat in 2003 and indicates an unabated continuation of glacier shrinkage in the Alps since the mid-1980s. It is a lower-bound estimate, as due to the higher spatial resolution of S2 many small glaciers were additionally mapped or increased in size compared to 2003. Median elevations peak around 3000 m a.s.l., with a high variability that depends on location and aspect. The uncertainty assessment revealed locally strong differences in interpretation of debris-covered glaciers, resulting in limitations for change assessment when using glacier extents digitized by different analysts. The inventory is available at https://doi.org/10.1594/PANGAEA.909133 (Paul et al., 2019).

scholarly journals Glacier shrinkage in the Alps continues unabated as revealed by a new glacier inventory from Sentinel-2

2019 ◽  
Author(s):  
Frank Paul ◽  
Philipp Rastner ◽  
Roberto Sergio Azzoni ◽  
Guglielmina Diolaiuti ◽  
Davide Fugazza ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Uncertainty Assessment ◽  
Ratio Method ◽  
Band Ratio ◽  
Glacier Inventory ◽  
Glacier Shrinkage ◽  
Run Off ◽  
Glacier Ice ◽  
The Alps ◽  
Sentinel 2

Abstract. The on-going glacier shrinkage in the Alps requires frequent updates of glacier outlines to provide an accurate database for monitoring or modeling purposes (e.g. determination of run-off, mass balance, or future glacier extent) and other applications. With the launch of the first Sentinel-2 (S2) satellite in 2015, it became possible to create a consistent, Alpine-wide glacier inventory with an unprecedented spatial resolution of 10 m. Fortunately, already the first S2 images acquired in August 2015 provided excellent mapping conditions for most of the glacierised regions in the Alps. We have used this opportunity to compile a new Alpine-wide glacier inventory in a collaborative team effort. In all countries, glacier outlines from the latest national inventories have been used as a guide to compile a consistent update. However, cloud cover over many glaciers in Italy required including also S2 scenes from 2016. Whereas the automated mapping of clean glacier ice was straightforward using the band ratio method, the numerous debris-covered glaciers required in-tense manual editing. The uncertainty in the outlines was determined with a multiple digitising experiment of 14 glaciers by all participants. Topographic information for all glaciers was derived from the ALOS AW3D30 DEM. Overall, we derived a total glacier area of 1806 ± 60 km2 when considering 4394 glaciers > 0.01 km2. This is 14 % (−1.2 %/a) less than the 2100 km2 derived from Landsat scenes acquired in 2003 and indicating an unabated continuation of glacier shrinkage in the Alps since the mid-1980s. Due to the higher spatial resolution of S2 many small glaciers were additionally mapped in the new inventory or increased in size compared to 2003. An artificial reduction to the former extents would thus result in an even higher overall area loss. Still, the uncertainty assessment revealed locally considerable differences in interpretation of debris-covered glaciers, resulting in limitations for change assessment when using glacier extents digitised by different analysts. The inventory is available at: https://doi.pangaea.de/10.1594/PANGAEA.909133 (Paul et al., 2019).

Studies of Ptiliidae (Coleoptera) in the Spirit Collection of the Natural History Museum, London 2: New species and records from P. Hammond's visit to New Zealand in 1983–84

2018 ◽  
Vol 154 (3) ◽  
pp. 179-196
Author(s):  
Michael Darby
Keyword(s):  
New Species ◽  
New Zealand ◽  
Natural History ◽  
Natural History Museum ◽  
History Museum ◽  
The North ◽  
Three New Species ◽  
North And South

Some 2,000 Ptiliidae collected in the North and South Islands of New Zealand in 1983/1984 by Peter Hammond of the Natural History Museum, London, are determined to 34 species, four of which are new to the country. As there are very few previous records, most from the Auckland district of North Island, the Hammond collection provides much new distributional data. The three new species: Nellosana insperatus sp. n., Notoptenidium flavum sp. n., and Notoptenidium johnsoni sp. n., are described and figured; the genus Ptiliodes is moved from Acrotrichinae to Ptiliinae, and Ptenidium formicetorum Kraatz recorded as a new introduction. Information is provided to aid separation of the new species from those previously recorded.

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