A Comparison and Study on Artificial Boundaries: Conceptual Aspects

The paper first analyzes the characteristics of various artificial boundaries (similarity and dissimilarity) and the derivation conditions of the boundaries. The problems involved in applying the artificial boundary in numerical computation and the solution to the problem are also discussed in the paper

Earthquake Risk and Earthquake Catastrophe Insurance for the People's Republic of China

The year 2008 witnessed the renewed interests in earthquake risk management and insurance in the People's Republic of China (PRC), after the Wenchuan earthquake hit the country in May. Located along the southeastern edge of the Euro-Asian Plate, the PRC has a relatively high seismicity, which is manifested by the frequent occurrence of large and disastrous earthquakes. Buildings and infrastructure in the earthquake-prone regions of the PRC have relatively low earthquake resistance levels. Hence, disastrous earthquakes result not only in large numbers of injuries and fatalities but also in huge economic losses from property damages. While the PRC began testing earthquake insurance programs in the late 1980s, the overall penetration rate remains very low. The low penetration rate not only creates disruptions for the government after a major earthquake but also, in some cases, delays the reconstruction efforts. Moreover, as a result of the low penetration of earthquake insurance in the PRC, the government serves as the predominant bearer of financial risk from earthquake catastrophes. This paper discusses historical earthquakes and earthquake risk in the PRC and the recent developments of PRC's earthquake risk reduction efforts. The general principles of earthquake programs are explained and the critical issues of formulating earthquake programs in the PRC are discussed, including lessons from earthquake insurance in other countries and other catastrophe insurance in the PRC, data issues, loss risk modeling issues, financial risk modeling issues, legislative issues, and public awareness issues. The paper concludes with several policy directions that the Asian Development Bank can take to help the PRC in its design and implementation of earthquake insurance.earthquake insurance; China; earthquake risk; Wenchuan earthquake; catastrophe insurance

Assessing the effects of trans-boundary aerosol transport between various city clusters on regional haze episodes in spring over East China

Regional haze episodes have been frequently reported in east China since 2000. In the present study, two regional haze episodes over east China in the spring of 2011 were examined by observations and simulations conducted by a three-dimensional regional chemical transport model (NAQPMS) with an on-line tracer-tagged module. The model reproduced accurately the observed PM2.5 with correlation coefficient ranging from 0.52 to 0.76 and root mean square error (RMSE) of 20–50µg/m3 in four city clusters (Yangtze River Delta, Shandong Peninsula, Huabei Plain and Central Liaoning) over east China. Our results indicate that a northward cross-border transport from the Yangtze River Delta to Central Liaoning below 2 km above ground played an important role in the formation of these regional high PM2.5 episodes. Contributions of regional transport from outside city clusters presented an increasing trend from south to north. In the northernmost cluster (Central Liaoning), the contribution from other city clusters reached 40–50% during the two episodes. In contrast, it was below 10% in the Yangtze River Delta (southernmost cluster). Mixing accumulation of pollutants from various city clusters during transport was responsible for this trend. Furthermore, a preliminary estimate shows that cross-border transport of PM2.5 might increase 0.5–3% daily mortality during the high PM2.5 episodes

Modeling and Optimal Control of Atmospheric Pollution Hazard in Nuclear and Chemical Disasters

AbstractNuclear and chemical disasters can cause heavy atmospheric pollution hazard and threat people's lives and health. In this paper, theory and application for modeling and optimal control of such hazard is studied. The modeling is based on the simulation and visualization of atmospheric dispersion of pollutants, the source term estimation of nuclear and chemical disasters, and the risk evaluation of hazardous substances. The optimal control is based on Natural Cybernetics theory, effective and economic cost evaluation of control techniques, and optimization methods. Some applications and illustrations of modeling and optimal control are reported

Earthquake Risk and Earthquake Catastrophe Insurance for the People's Republic of China

The year 2008 witnessed the renewed interests in earthquake risk management and insurance in the People's Republic of China (PRC), after the Wenchuan earthquake hit the country in May. Located along the southeastern edge of the Euro-Asian Plate, the PRC has a relatively high seismicity, which is manifested by the frequent occurrence of large and disastrous earthquakes. Buildings and infrastructure in the earthquake-prone regions of the PRC have relatively low earthquake resistance levels. Hence, disastrous earthquakes result not only in large numbers of injuries and fatalities but also in huge economic losses from property damages. While the PRC began testing earthquake insurance programs in the late 1980s, the overall penetration rate remains very low. The low penetration rate not only creates disruptions for the government after a major earthquake but also, in some cases, delays the reconstruction efforts. Moreover, as a result of the low penetration of earthquake insurance in the PRC, the government serves as the predominant bearer of financial risk from earthquake catastrophes. This paper discusses historical earthquakes and earthquake risk in the PRC and the recent developments of PRC's earthquake risk reduction efforts. The general principles of earthquake programs are explained and the critical issues of formulating earthquake programs in the PRC are discussed, including lessons from earthquake insurance in other countries and other catastrophe insurance in the PRC, data issues, loss risk modeling issues, financial risk modeling issues, legislative issues, and public awareness issues. The paper concludes with several policy directions that the Asian Development Bank can take to help the PRC in its design and implementation of earthquake insurance

NAQPMS-PDAF v2.0: A Novel Hybrid Nonlinear Data Assimilation System for Improved Simulation of PM2.5 Chemical Components

PM2.5, a complex mixture with diverse chemical components, exerts significant impacts on the environment, human health, and climate change. However, precisely describing spatiotemporal variations of PM2.5 chemical components remains a difficulty. In our earlier work, we developed an aerosol extinction coefficient data assimilation (DA) system (NAQPMS-PDAF v1.0) that is suboptimal for chemical components. This paper introduces a novel hybrid nonlinear chemical DA system (NAQPMS-PDAF v2.0) to accurately interpret key chemical components (SO42-, NO3-, NH4+, OC, and EC). NAQPMS-PDAF v2.0 improves upon v1.0 by effectively handing and balancing stability and nonlinearity in chemical DA, which is achieved by incorporating the non-Gaussian-distribution ensemble perturbation and hybrid Localized Kalman-Nonlinear Ensemble Transform Filter with an adaptive forgetting factor for the first time. The dependence tests demonstrate that NAQPMS-PDAF v2.0 provides excellent DA results with a minimal ensemble size of 10, surpassing previous reports and v1.0. A one-month DA experiment shows that the analysis field generated by NAQPMS-PDAF v2.0 is in good agreement with observations, especially reducing the underestimation of NH4+ and NO3- and the overestimation of SO42-, OC, and EC. In particular, the CORR values for NO3-, OC, and EC are above 0.96, and R2 values are above 0.93. NAQPMS-PDAF v2.0 also demonstrates superior spatiotemporal interpretation, with most DA sites showing improvements of over 50 %–200 % in CORR and over 50 %–90 % in RMSE for the five chemical components. Compared to the poor performance in global reanalysis dataset (CORR: 0.42–0.55, RMSE: 4.51–12.27 µg/m3) and NAQPMS-PDAF v1.0 (CORR: 0.35–0.98, RMSE: 2.46–15.50 µg/m3), NAQPMS-PDAF v2.0 has the highest CORR of 0.86–0.99 and the lowest RMSE of 0.14–3.18 µg/m3. The uncertainties in ensemble DA are also examined, further highlighting the potential of NAQPMS-PDAF v2.0 for advancing aerosol chemical component studies