Teleconnection analysis of runoff and soil moisture over the Pearl River basin in Southern China

This study explores the teleconnection of two climatic patterns, namely the El Niño–Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD), with hydrological processes over the Pearl River basin in southern China, particularly on a sub-basin-scale basis. The Variable Infiltration Capacity (VIC) model is used to simulate the daily hydrological processes over the basin for the study period 1952–2000, and then, using the simulation results, the time series of the monthly runoff and soil moisture anomalies for its ten sub-basins are aggregated. Wavelet analysis is performed to explore the variability properties of these time series at 49 timescales ranging from 2 months to 9 yr. Use of the wavelet coherence and rank correlation method reveals that the dominant variabilities of the time series of runoff and soil moisture are basically correlated with IOD. The influences of ENSO on the terrestrial hydrological processes are mainly found in the eastern sub-basins. The teleconnections between climatic patterns and hydrological variability also serve as a reference for inferences on the occurrence of extreme hydrological events (e.g., floods and droughts).published_or_final_versio

The unresolved stochastic background from compact binary mergers detectable by next-generation ground-based gravitational-wave observatories

The next generation of ground-based gravitational-wave detectors will look much deeper into the Universe and have unprecedented sensitivities and low-frequency capabilities. Especially alluring is the possibility of detecting an early-Universe cosmological stochastic background that could provide important insights into the beginnings of our Universe and fundamental physics at extremely high energies. However, even if next-generation detectors are sensitive to cosmological stochastic backgrounds, they will be masked by more dominant astrophysical backgrounds, namely the residual background from the imperfect subtraction of resolvable compact binary coalescences (CBCs) as well as the CBC background from individually unresolvable CBCs. Using our latest knowledge of masses, rates, and delay time distributions, we present a data-driven estimate of the unresolvable CBC background that will be seen by next-generation detectors. Accounting for statistical and systematic errors, this estimate quantifies an important piece in the CBC noise budget for next-generation detectors and can help inform detector design and subtraction algorithms. We compare our results with predictions for backgrounds from several cosmological sources in the literature, finding that the unresolvable background will likely be a significant impediment for many models. This motivates the need for simultaneous inference methods or other statistical techniques to detect early-Universe cosmological backgrounds.Comment: 19 pages, 8 figure

KNOWLEDGE SHARING AND INFORMATION QUALITY AS MEDIATED BY MOBILE LEARNING SYSTEM USAGE OF SENIOR HIGH STUDENTS

This study aimed to determine the mediating effect of mobile learning system-usage of Davao City National High School senior high students between knowledge sharing and information quality. A stratified random sampling method was adopted, with 319 students as respondents. The researcher collected the data using a Google form delivered to the respondents. The results of a non-experimental quantitative mediation analysis using a validated questionnaire, mean, regression techniques, and Pearson r revealed a significant relationship between knowledge sharing, information quality, and mobile learning system usage. The findings revealed that senior high students' level of knowledge sharing was high. Likewise, the level of information quality of senior high students was high. In addition, the Level of Mobile Learning System Usage suggested that the outcome was high. Since the mediating effect causal steps approach in this study revealed a non-significant relationship between knowledge sharing and information quality, there was a complete mediation on the effect of mobile learning system usage on the relationship between knowledge sharing and information quality. As a result, mobile learning systems influence students' knowledge sharing and information quality, and vice versa.  Article visualizations

Evolution of storm direct runoff recorded at a headwater catchment in Hong Kong

The 2011 Conference of the Asia Oceania Geosciences Society (AOGS2011), Taipei, Taiwan, 8-12 August 2011

Electronic, geometrical, and thermochemical studies on group-14 element-diruthenaborane cluster compounds: a theoretical investigation

International audienc

Effect of catchment characteristics on the relationship between past discharge and the power law recession coefficient

This study concerns the relationship between the power law recession coefficient k (in −dQ/dt = kQα, Q being discharge at the basin outlet) and past average discharge QN (where N is the temporal distance from the center of the selected time span in the past to the recession peak), which serves as a proxy for past storage state of the basin. The strength of the k–QN relationship is characterized by the coefficient of determination R2N, which is expected to indicate the basin’s ability to hold water for N days. The main objective of this study is to examine how R2N value of a basin is related with its physical characteristics. For this purpose, we use streamflow data from 358 basins in the United States and selected 18 physical parameters for each basin. First, we transform the physical parameters into mutually independent principal components. Then we employ multiple linear regression method to construct a model of R2N in terms of the principal components. Furthermore, we employ step-wise multiple linear regression method to identify the dominant catchment characteristics that influence R2N and their directions of influence. Our results indicate that R2N is appreciably related to catchment characteristics. Particularly, it is noteworthy that the coefficient of determination of the relationship between R2N and the catchment characteristics is 0.643 for N = 45. We found that topographical characteristics of a basin are the most dominant factors in controlling the value of R2N. Our results may be suggesting that it is possible to tell about the water holding capacity of a basin by just knowing about a few of its physical characteristics