Estimation of recent changes in thickness and mass balance of the Patsio glacier in the Great Himalayan region using geodetic technique and ancillary data

2018 ◽  
Vol 35 (1) ◽  
pp. 47-63 ◽  
Author(s):  
Anant Kumar ◽  
Harendra Singh Negi ◽  
Kamal Kumar ◽  
Neha Kanda ◽  
Kamal Kant Singh ◽  
...  
Keyword(s):  
Mass Balance ◽  
Himalayan Region ◽  
Ancillary Data ◽  
Geodetic Technique

scholarly journals Quantifying mass balance of East-Karakoram glaciers using geodetic technique

Polar Science ◽  
2019 ◽  
Vol 19 ◽  
pp. 24-39 ◽  
Author(s):  
Anant Kumar ◽  
H.S. Negi ◽  
Kamal Kumar ◽  
Chander Shekhar ◽  
Neha Kanda
Keyword(s):  
Mass Balance ◽  
Geodetic Technique

Estimating Mass Balance of White Glacier using ICESat-2

2021 ◽  
Author(s):  
Rachel Lackey
Keyword(s):  
Mass Balance ◽  
Laser Beams ◽  
Altimeter Data ◽  
Altimetry Data ◽  
Laser Altimeter ◽  
Ice Cloud ◽  
Geodetic Technique ◽  
Travel Restrictions ◽  
The Difference ◽  
Satellite Altimetry Data

White Glacier is located on Axel Heiberg Island in Nunavut, Canada, and has had its mass balance actively monitored since 1960. Due to COVID-19 travel restrictions it not possible for researchers to travel to White Glacier and perform the measurements required. This results in gaps in data required to determine the mass balance for 2018-2020. In this study we aim to collect and process laser altimeter data to be interpolated to calculate an estimate of the Mass Balance of White Glacier. This study will be completed using a geodetic technique that utilizes the Ice Cloud and Elevation-2 (ICESat-2) satellite altimetry data. ICESat-2 is carrying ATLAS which is an Advanced Topographic Laser Altimeter that is equipped with six laser beams divided into three pairs that measure lidar altimetry to derive surface height. The longitude, latitude, datetime, and land ice height values were extracted over the Expedition fjord region using MATLAB. The land ice tracks were brought into ArcGIS for analysis, three repeat tracks in the Expedition Fjord region were selected for analysis to determine the difference in elevation between the premelt seasons of 2019 and 2020 as well as one track comparing the premelt and melt seasons of 2019. These elevation differences will be interpolated as accumulation or ablation dependant on the location on the glacier and used to estimate mass balance.

Mapping estimated deep drainage in the lower Namoi Valley using a chloride mass balance model and EM34 data

Geophysics ◽  
2012 ◽  
Vol 77 (4) ◽  
pp. WB245-WB256 ◽  
Author(s):  
A. Woodforth ◽  
J. Triantafilis ◽  
J. Cupitt ◽  
R. S. Malik ◽  
R. Subasinghe ◽  
...  
Keyword(s):  
Mass Balance ◽  
Multiple Linear Regression Model ◽  
Balance Model ◽  
Chloride Mass Balance ◽  
Cotton Production ◽  
Stream Channels ◽  
Large Area ◽  
Deep Drainage ◽  
Ancillary Data ◽  
Trend Surface

The Murray Darling Basin accounts for half of all water used for irrigation in Australia. However, improvements in water use efficiency (WUE) are required, owing to increasing demands on water (e.g., environmental flows). This requires data on the spatial distribution of soil-hydrological properties, such as deep drainage (DD). Measuring DD using lysimeters, although accurate, is site-specific. Alternatively, estimates are commonly made using chloride mass balance (CMB) models. Gaining this information across a large area is still problematic due to the prohibitive cost of drilling, sampling, and laboratory analysis. Ancillary data, obtained from electromagnetic (EM) instruments, have been used to add value to a limited number of DD estimates. We evaluated the use of a hierarchical spatial regression technique to map the estimated DD using a steady state CMB model coupled to EM34 measurements. We first compared a standard least squares and a stepwise multiple linear regression model. The former includes the use of EM34 signal data in the horizontal (EM34-10H, EM34-20H, and EM34-40H) and vertical (EM34-10V, EM34-20V, and EM34-40V) dipoles, as well as two trend surface variables (scaled easting and northing). The latter model only includes a statistically significant ancillary variable (EM34-10H) and a trend surface parameter (scaled northing), and we use this to estimate DD across the lower Namoi Valley. EM34 data available on a 1 km grid proved useful for mapping DD on a reconnaissance level, with the results closely related to the physiography. In particular, large DD estimates are associated with the prior stream channels. Conversely, smaller DD estimates characterize the agriculturally significant clay plain which is used extensively for irrigated cotton production. The map of estimated DD will allow improved siting of dams and irrigation fields, as well as indicate where more efficient cropping or irrigation systems can be implemented to increase WUE.

Investigation into Cigarette Smoking and Atmospheric Pollution in the Aetiology of Lung Cancer

1963 ◽  
Vol 2 (01) ◽  
pp. 13-19 ◽  
Author(s):  
R. Doll
Keyword(s):  
Lung Cancer ◽  
Cigarette Smoking ◽  
Atmospheric Pollution ◽  
Direct Evidence ◽  
Retrospective Studies ◽  
Common Factor ◽  
Animal Experiments ◽  
Smoking Habits ◽  
Careful Examination ◽  
Ancillary Data

The evidence that cigarette smoking and atmospheric pcllution are causes of lung cancer is largely statistical. The first evidence was indirect; that is, i1. was noticed that in many countries the incidence of lung cancer had increased and that the increase could be correlated with changes in the prevalence of cigarette smoking and of certain types of atmospheric pollution.Since then much direct evidence has been obtained. The relationship between cigarette smoking and lung cancer has been demonstrated retrospectively by comparing the smoking habits of patients with and without lung cancer and prospectively by observing the mortality from lung cancer in groups of persons of known smoking habits. Conclusions can be drawn from these studies only after careful examination of the results. In particular it is important in retrospective studies to test a) the reproducibility of the data, b) the representativeness of the data, and c) the comparability of the special series and their controls. The resul1.s of retrospective studies are all similar and all show a close relationship between cigarette smoking and the disease.The results have been confirmed by pro~pective studies which are lesF. open to bias. The results can be explained if cigarette smoking causes lung cancer or if both are related to some third common factor. Ancillary data (pathological changes in the bronchial mucosa, animal experiments, etc.) support the causal hypothesis.The evidence relating to atmospheric pollution is less definite and it is difficult to get direct evidence of a relationship in the individual. It is clear that pollution has little effect in the absence of smoking, but the mortality associated with a given amount of smoking is generally greater in large towns than in the countryside and among men who have emigrated from Britain than among men who have lived all their lives in less polluted countries.

Cyathodium denticulatum Udar et Srivastava: A rare liverwort new to Chhattisgarh, Central India

2020 ◽  
pp. 171-174
Author(s):  
Ashwini Kumar Dixit ◽  
Mery Aradhna Kerketta
Keyword(s):  
Rare Species ◽  
Biosphere Reserve ◽  
Central India ◽  
Himalayan Region ◽  
Taxonomic Description ◽  
First Time ◽  
Eastern Himalayan Region

This article reports the occurrence of the thalloid liverwort Cyathodium denticulatum Udar et Srivastava was collected first time from the Achanakmar – Amarkantak Biosphere Reserve (AABR) Bilaspur, Chhattisgarh. It is shown that Cyathodium denticulatum a narrow Himalayan endemic has been reported earlier from Darjeeling, India. There is no record of its occurrence from central India. Cyathodium denticulatum is a rare species known only from eastern Himalayan region. A key to related Indian taxa and taxonomic description is provided.

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