Perturbed physics ensemble using the MIROC5 coupled atmosphere–ocean GCM without flux corrections: experimental design and results

In this study, we constructed a perturbed physics ensemble (PPE) for the MIROC5 coupled atmosphere–ocean general circulation model (CGCM) to investigate the parametric uncertainty of climate sensitivity (CS). Previous studies of PPEs have mainly used the atmosphere-slab ocean models. A few PPE studies using a CGCM applied flux corrections, because perturbations in parameters can lead to large radiation imbalances at the top of the atmosphere and climate drifts. We developed a method to prevent climate drifts in PPE experiments using the MIROC5 CGCM without flux corrections. We simultaneously swept 10 parameters in atmosphere and surface schemes. The range of CS (estimated from our 35 ensemble members) was not wide (2.2–3.2?°C). The shortwave cloud feedback related to changes in middle-level cloud albedo dominated the variations in the total feedback. We found three performance metrics for the present climate simulations of middle-level cloud albedo, precipitation, and ENSO amplitude that systematically relate to the variations in shortwave cloud feedback in this PPE.     

Soil water retention behavior and microstructure evolution of lateritic soil in the suction range of 0–286.7 MPa

Acta Geotechnica - This paper presents an experimental investigation of the soil water retention curve (SWRC) and volume change curve over a large suction range (0–286.7 MPa), and...     

On the generation and interpretation of probabilistic estimates of climate sensitivity

The equilibrium climate response to anthropogenic forcing has long been one of the dominant, and therefore most intensively studied, uncertainties in predicting future climate change. As a result, many probabilistic estimates of the climate sensitivity (S) have been presented. In recent years, most of them have assigned significant probability to extremely high sensitivity, such as P(S?>?6C)?>?5%. In this paper, we investigate some of the assumptions underlying these estimates. We show that the popular choice of a uniform prior has unacceptable properties and cannot be reasonably considered to generate meaningful and usable results. When instead reasonable assumptions are made, much greater confidence in a moderate value for S is easily justified, with an upper 95% probability limit for S easily shown to lie close to 4°C, and certainly well below 6°C. These results also impact strongly on projected economic losses due to climate change.     

Shear Strength Criteria for Unsaturated Soils

Shear strength is one of the fundamental properties of unsaturated soils. It has been found to change with matric suction. Various shear strength equations have been proposed for predicting the shear strength versus suction relationship for unsaturated soils. Some of these equations are based on regression analysis of experimental data, while some are embodied in more complex stress–strain constitutive models. In this paper, a variety of shear strength equations are examined and compared with respect to their fit of experimental data. Data for specimens prepared from initially slurry conditions as well as data for initially compacted soil specimens are analysed. The advantages and limitations associated with various proposed shear strength equations are discussed in this paper.     

Recovering Bathymetry of the Gulf of Guinea Using Altimetry-Derived Gravity Field Products Combined via Convolutional Neural Network

Surveys in Geophysics - Traditional methods of bathymetry inversion from altimetry data often use gravity anomalies and/or vertical gravity anomaly gradients. These two gravity products are usually...     

Investigation on fatal accidents in Chinese construction industry between 2004 and 2016

This paper summarizes a number of fatal accidents that occurred in the Chinese construction industry from 2004 to 2016, and more detailed analysis is conducted on the data between 2010 and 2016. The data collected from 2010 to 2016 reveal that 3817 fatal accidents occurred during the construction of buildings and municipal facilities. Analysis is conducted to reveal the reasons of these construction accidents. The number of fatalities and accidents, the types of accidents, the effect of climate factors, the time period distribution of accidents, and provincial distribution are analyzed and compared. The results show that, falling from heights is the main cause of fatal accidents. The number of fatalities and accidents varies sharply across provinces and is closely related to the climate (the same gross output with less accidents in the cold weather areas). Due to annual transferring and traditional Chinese Spring Festival, project schedule is generally arranged less in December, January, and February so that a lower number of accidents are reported in these months. Daily, accidents in the afternoon are higher than that in the morning.     

A multisurface elastoplastic model for frozen soil

Acta Geotechnica - Many geotechnical engineering problems in the cold region, including cracking of pavements, damage to the foundations of structures, and fracture of pipelines are blamed due to...