scholarly journals Correlation Analysis of NINO3.4 SST and Inland Lake Level Variations Monitored with Satellite Altimetry: Case Studies of Lakes Hongze, Khanka, La-ang, Ulungur, Issyk-kul and Baikal

2011 ◽  
Vol 22 (2) ◽  
pp. 203-213 ◽  
Author(s):  
Jinyun Guo ◽  
Jialong Sun ◽  
Xiaotao Chang ◽  
Shuyan Guo ◽  
Xin Liu
Keyword(s):  
Correlation Analysis ◽  
Case Studies ◽  
Satellite Altimetry ◽  
Lake Level ◽  
Inland Lake

Determination of Inland Lake Level and Its Variations in China from Satellite Altimetry

2008 ◽  
pp. 80-83
Author(s):  
Yonghai Chu ◽  
J. Li ◽  
Weiping Jiang ◽  
Xiancai Zou ◽  
Xinyu Xu ◽  
...  
Keyword(s):  
Satellite Altimetry ◽  
Lake Level ◽  
Inland Lake

scholarly journals Role of Upper-Flow-Regime Bedforms Emplaced by Sediment Gravity Flows in the Evolution of Deltas

2019 ◽  
Vol 7 (1) ◽  
pp. 5 ◽  
Author(s):  
Svetlana Kostic ◽  
Daniele Casalbore ◽  
Francesco Chiocci ◽  
Jörg Lang ◽  
Jutta Winsemann
Keyword(s):  
Numerical Analysis ◽  
High Resolution ◽  
Flow Regime ◽  
Case Studies ◽  
Seismic Data ◽  
Lake Level ◽  
Sediment Gravity Flows ◽  
Gravity Flows ◽  
Digital Elevation

Upper-flow-regime bedforms and their role in the evolution of marine and lacustrine deltas are not well understood. Wave-like undulations on delta foresets are by far the most commonly reported bedforms on deltas and it will take time before many of these features get identified as upper-flow-regime bedforms. This study aims at: (1) Providing a summary of our knowledge to date on deltaic bedforms emplaced by sediment gravity flows; (2) illustrating that these features are most likely transitional upper-flow-regime bedforms; and (3) using field case studies of two markedly different deltas in order to examine their role in the evolution of deltas. The study combines numerical analysis with digital elevation models, outcrop, borehole, and high-resolution seismic data. The Mazzarrà river delta in the Gulf of Patti, Italy, is selected to show that upper-flow-regime bedforms in gullies can be linked to the onset, growth, and evolution of marine deltas via processes of gully initiation, filling, and maintenance. Ice-marginal lacustrine deltas in Germany are selected as they illustrate the importance of unconfined upper-flow-regime bedforms in the onset and evolution of distinct delta morphologies under different lake-level trends.

scholarly journals Validation of Sentinel-3A Based Lake Level over US and Canada

2020 ◽  
Vol 12 (17) ◽  
pp. 2835
Author(s):  
Karina Nielsen ◽  
Ole Baltazar Andersen ◽  
Heidi Ranndal
Keyword(s):  
Water Level ◽  
Satellite Altimetry ◽  
Lake Level ◽  
Mean Squared Error ◽  
Pearson Correlation ◽  
The United States ◽  
Water Levels ◽  
Winter Period ◽  
Large Lakes ◽  
In Situ Data

Satellite altimetry is an important contributor for measuring the water level of continental water bodies. The technique has been applied for almost three decades. In this period the data quality has increased and the applications have evolved from the study of a few large lakes and rivers, to near global applications at various scales. Products from current satellite altimetry missions should be validated to continuously improve the measurements. Sentinel-3A has been operating since 2016 and is the first mission operating in synthetic aperture radar (SAR) mode globally. Here we evaluate its performance in capturing lake level variations based on a physical and an empirical retracker provided in the official level 2 product. The validation is performed for more than 100 lakes in the United States and Canada where the altimetry based water levels are compared with in situ data. As validation measures we consider the root mean squared error, the Pearson correlation, and the percentage of outliers. For the US sites the median of the RMSE value is 25 cm and 19 cm and the median of the Pearson correlations are 0.86 and 0.93 for the physical and empirical retracker, respectively. The percentage of outliers (median) is 11% for both retrackers. The validations measures are slightly poorer for the Canadian sites; the median RMSE is approximately 5 cm larger, the Pearson correlation 0.1 lower, and the percentage of outliers 5% larger. The poorer performance for the Canadian sites is mainly related to the presence of lake ice in the winter period where the surface elevations are not able to map the surface correctly. The validation measures improve considerably when evaluated for summer data only. For both areas we show that the reconstruction of the water level variations based on the empirical retracker is significantly better compared to that of the physical retracker in terms of the RMSE and the Pearson correlation.

scholarly journals Interannual variability of the lake levels in northwest Russia based on satellite altimetry

2015 ◽  
Vol 365 ◽  
pp. 91-97
Author(s):  
S. A. Lebedev ◽  
Y. I. Troitskaya ◽  
G. V. Rybushkina ◽  
M. N. Dobrovolsky
Keyword(s):  
Water Level ◽  
Interannual Variability ◽  
Temporal Variability ◽  
Satellite Altimetry ◽  
Lake Level ◽  
Lake Ladoga ◽  
Lake Levels ◽  
Lake Onega ◽  
Lake Ilmen ◽  
Altimetric Measurements

Abstract. Variability of the largest lakes levels in northwest Russia, a climatic change parameter, is characterized by alternating periods of rise and fall according to altimetric measurements of the TOPEX/Poseidon and Jason-1/2 satellites. Water level was calculated with the use of a regional adaptive retracking algorithm for the lakes Il’men, Ladoga, Onega and Peipus. Applications of this algorithm considerably increase the quantity of actual data records and significantly improve the accuracy of water level evaluation. According to the results, temporal variability of Lake Ilmen, Lake Ladoga and Lake Piepus levels is characterized by a wave with a period of 4–5 years, and that of Lake Onega level is characterized by a wave with a period of 15 years. During the period from 1993 to 2011, lake level rose at a rate of 1.17±0.95 cm/year for Lake Il’men, 0.24 ± 0.10 cm/year for Lake Ladoga, 1.39 ± 0.18 cm/year for Lake Piepus and 0.18 ± 0.09 cm/year for Lake Onega.

China and United Nations Security Council Sanctions

2020 ◽  
Author(s):  
Angela Poh
Keyword(s):  
Correlation Analysis ◽  
United Nations ◽  
Case Studies ◽  
Security Council ◽  
United Nations Security Council ◽  
Decision Makers ◽  
Voting Behaviour ◽  
Economic Interests ◽  
Guinea Bissau

Chapter 5 uses the dataset of sanctions-related resolutions tabled at the UNSC from 1971 to 2016 to present a correlation analysis that examines the extent to which expectations derived from the ‘rhetoric-based’ hypothesis align with China’s voting behaviour at the UNSC. Thereafter, it examines the backgrounds, debates, and outcomes concerning three case studies: UN sanctions against the DPRK (2006-2016); Syria (2011-2016); and Guinea- Bissau (2012). It examines whether the hypothesised constraining role of China’s sanctions rhetoric or one of the competing explanations best accounts for the outcomes in each case. It finds that China’s sanctions rhetoric had frequently prompted its decision-makers to act or vote in ways that were not the most favourable to China’s immediate political and economic interests.

Pengembangan Kriteria dan Klasifikasi Tingkat Kekritisan Lahan pada Skala Tinjau di Kawasan Budidaya Pertanian Lahan Kering di Kabupaten Bogor

Agrotek ◽  
2018 ◽  
Vol 2 (6) ◽  
Author(s):  
Mashudi Mashudi
Keyword(s):  
Cluster Analysis ◽  
Data Analysis ◽  
Discriminant Analysis ◽  
Correlation Analysis ◽  
Case Studies ◽  
Soil Depth ◽  
Survey Method ◽  
Bivariate Correlation ◽  
Critical Class ◽  
Data Analysis Methods

<em>The objectives of this research are to develop critical land criteria and classification on the reconnaissance scales. The method used in this research is survey method through case studies. Data analysis methods include: bivariate correlation analysis, cluster analysis, and discriminant analysis. The results showed development criteria at reconnaissance scale resulted three determinant variables, namely: effective soil depth, stones, and degree of erosion; and produced two classes of critical land, namely: Critical class and Non-Critical class.</em>

Lake Level Variations Monitored With Satellite Altimetry Waveform Retracking

2009 ◽  
Vol 2 (2) ◽  
pp. 80-86 ◽  
Author(s):  
Jinyun Guo ◽  
Xiaotao Chang ◽  
Yonggang Gao ◽  
Jialong Sun ◽  
Cheinway Hwang
Keyword(s):  
Satellite Altimetry ◽  
Lake Level ◽  
Waveform Retracking
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