A Comprehensive Analysis of a Heavy Precipitation Event in Chengdu Plain (China) Based on Ground-Based GPS
Wang Hao,
Wang Yue,
Wang Yongqian
Issue:
Volume 5, Issue 4, August 2016
Pages:
48-55
Received:
3 August 2016
Accepted:
11 August 2016
Published:
31 August 2016
Abstract: This study utilized the ground-based GPS water vapor monitoring network in the Chengdu Plain (102.9°–104.9°E, 30.1°–31.4°N), alongside radiosonde data and National Center for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR) reanalysis data, to conduct a comprehensive analysis of a heavy precipitation event in this region in 2008. Correlations were found between the GPS precipitable water vapor (GPS-PWV) variations, the actual precipitation in the region, and the physical mechanism for the GPS-PWV variations. The research results indicate that the variation trends in precipitable water vapor had a significant correlation with actual precipitation. The precipitable water vapor increased and decreased significantly before and after the precipitation event, respectively. The residence time of precipitable water vapor at high levels was correlated with the duration of actual precipitation to some extent. The maximum value of the precipitation intensity lagged behind the precipitable water vapor peak, which brought forward precipitation to a certain degree. A strong ascending motion of the air was linked to increases in PWV, and the intensity of the ascending motion was strongly correlated with GPS-PWV. Different atmospheric thermodynamic conditions also had a notable effect on GPS-PWV variations.
Abstract: This study utilized the ground-based GPS water vapor monitoring network in the Chengdu Plain (102.9°–104.9°E, 30.1°–31.4°N), alongside radiosonde data and National Center for Environmental Prediction and National Center for Atmospheric Research (NCEP/NCAR) reanalysis data, to conduct a comprehensive analysis of a heavy precipitation event in this r...
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Determination of Mine Location by Using Edge Detection Methods: A Case Study of Sivas-Divrigi
Fikret Dogru,
Oya Pamukcu,
Cagatay Pamukcu
Issue:
Volume 5, Issue 4, August 2016
Pages:
56-61
Received:
28 June 2016
Accepted:
16 July 2016
Published:
13 September 2016
Abstract: Edge detection and edge enhancement techniques play a crucial role in interpreting potential field data. There have been various edge detection applications to magnetic data in order to determine the edges of subsurface structures in geophysics. The edge detection methods comprise analytic signal, total horizontal derivative, theta angle, tilt angle. In synthetic case, two prism model used and the edge detection filters were applied on synthetic data successfully. In field study, the magnetic anomaly of Sivas-Divrigi mining area was selected because of importance of this area in terms of high-grade iron ore reserves. The mentioned method was applied on field data and the location of iron ore was revealed. As a conclusion, tilt angle and theta map methods gave a good agreement for determination of the structure location in both synthetic and field studies. In addition, tilt angle of the vertical derivative was studied both in theoretical and field applications. It was seen that residual information could be obtained in case tilt angle was taken following the vertical derivation.
Abstract: Edge detection and edge enhancement techniques play a crucial role in interpreting potential field data. There have been various edge detection applications to magnetic data in order to determine the edges of subsurface structures in geophysics. The edge detection methods comprise analytic signal, total horizontal derivative, theta angle, tilt angl...
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