ABSTRACT Conventional triaxial compression tests were conducted on shale specimens under varying initial prestress conditions to investigate their mechanical properties and energy evolution characteristics, thereby revealing the damage mechanism. The results demonstrate that peak differential stress of samples increases with rising prestress, following an exponential function. Based maximum minimum principal data Mohr‐Coulomb criterion, cohesive force internal friction angle tested...

Global climate warming and increased variability may increase the number of annual freeze–thaw cycles (FTCs) in temperate zones. The occurrence more frequent FTCs is predicted to influence soil carbon nitrogen leaching. Biochar has potential organic storage decrease This study aims investigate impact on leaching zones, considering exacerbation due global variability. focuses how biochar, a carbon-rich material produced from biomass, might mitigate by influencing characteristics. explores...

Abstract Hyperspectral infrared (IR) sounders, such as the Atmospheric Infrared Sounder (AIRS) and Sounding Interferometer (IASI), provide unprecedented global atmospheric temperature moisture soundings with high vertical resolution accuracy. In this paper, authors investigate whether advanced IR of water vapor observations can improve analysis a tropical cyclone vortex forecast rapid intensification cyclone. Both significantly typhoon in Typhoon Sinlaku (2008). The track is also...

Mid-level clouds play a crucial role in the Arctic. Due to observational limitations, there is scarce research on long-term evolution of Arctic mid-level clouds. From satellite perspective, this study attempts analyze seasonal variations and explore possible relationships with sea ice changes using observations from hyperspectral Atmospheric Infrared Sounder (AIRS) over past two decades. For three layers (648, 548, 447 hPa) involved AIRS, high values effective cloud fraction (ECF) occur...

In order to improve the operational application ability of Fengyun-4A (FY-4A) new sounding dataset, in this paper, validation FY-4A Geosynchronous Interferometric Infrared Sounder (FY-4A/GIIRS) temperature was carried out using balloon from meteorological stations. More than 350,000 samples were obtained through time-space matching, and results show that FY-4A/GIIRS mean bias (MB) is 0.07°C, absolute error (MAE) 1.80°C, root-mean-square (RMSE) 2.546°C, correlation coefficient (RR) 0.95. The...

There is significant archaeological evidence marking the collapse of Shijiahe culture in middle reaches Yangtze River China during late Neolithic Period. However, causes for this cultural remain unclear. Our sedimentary records from a 3.3 m long profile and 76 phytolith charcoal samples Tanjialing sites provide interactions between an ancient vegetation change. During early (c, 4850–4400 cal BP), climate was warm humid. Fire intensively used to clear vegetation. In mid-period 4400–4200...

Abstract To explore how to respond seasonal freeze–thaw cycles on forest ecosystems in the context of climate change through thinning, we assessed potential impact thinning intensity carbon cycle dynamics. By varying number temperature cycles, effects various intensities four seasons. The rate mass, litter organic carbon, and soil (SOC) loss response variations was examined two degrees decomposition. unfrozen season had highest decomposition litter, followed by frozen season. Semi-decomposed...

Poor air quality directly affects human health and has become an increasingly important environmental issue in Tianjin, China. The suspension of particulate matter (PM) the atmosphere is not only from industrial pollutants, but also soil wind erosion; however, contributions farmland, woodland, grassland have rarely been considered this region. We conducted assessment PM sources through erosion, dust emission, transportation urban rural areas to central district our results demonstrated that...

In this study, a new technique is proposed to retrieve temperature and relative humidity profiles under clear sky conditions in the Arctic region based on artificial neural network (ANN) algorithm using Fengyun-3D (FY-3D) vertical atmospheric sounder suit (VASS: HIRAS, MWTS-II, MWHS-II) observations. This technology combines infrared (IR) microwave (MW) observations improve retrieval accuracy middle low troposphere by reducing sensitivity of networks (NNs) cloud coverage. The approach was...

Abstract As global warming intensifies, the soil environment in middle to high latitudes will undergo more extensive and frequent freeze–thaw cycles (FTCs), which significantly affect carbon nitrogen of ecosystems aggravate greenhouse gas (GHG) emissions. Biochar can increase organic storage mitigate climate change. To effectively control GHG emissions, supplemented with biochar at different application rates (0%, 2%, 4% 6% [w/w]) under numbers FTCs (0, 3, 6, 9, 12) was selected as research...

A long-term dataset of 38 years (1982–2019) from the Advanced Very High Resolution Radiometer (AVHRR) satellite observations is applied to investigate spatio-temporal seasonal trends in cloud fraction, surface downwelling longwave flux, and upwelling flux over Arctic seas (60~90° N) by non-parametric methods. The results presented here provide a further contribution understand cover radiation seas, their correlations shrinking sea ice. Our suggest that fraction shows positive trend for all...

Abstract A three‐dimensional physical‐biological model has been used to simulate seasonal phytoplankton variations in the Bering and Chukchi Seas with a focus on understanding physical biogeochemical mechanisms involved formation of Sea Green Belt (GB) Subsurface Chlorophyll Maxima (SCM). Model results suggest that horizontal distribution GB is controlled by combination light, temperature, nutrients. indicated SCM, frequently seen below thermocline, exists because rich supply nutrients...

The acquisition of real-time temperature and relative humidity (RH) profiles in the Arctic is great significance for study Arctic’s climate scientific research. However, operational algorithm Fengyun-3D only takes into account areas within 60°N, innovation this work that a new technique based on Neural Network (NN) was proposed, which can retrieve these parameters real time from Hyperspectral Infrared Radiation Atmospheric Sounding (HIRAS) observations region. Considering difficulty...

The reliability of low frequencies is a crucial question for geophone records. An example the data recorded passive seismic studies using geophones paired with TEXAN miniature recorders, where high resonance frequency degrades low‐frequency waveforms and increases ambiguity in phase picking. We have evaluated such from mobile array geophone‐TEXAN pairs central China. response can be easily established Power Spectral Density Ratio (PSDR) between records broadband seismometer occupying same...

Low tropospheric temperature inversion is very common in the Arctic region. Based on hyperspectral Atmospheric Infrared Sounder (AIRS) profiles from 2002 to 2020, this study provides a comprehensive analysis of characteristics and anomalies for low inversions entire Arctic, especially during summer period. Three types are classified here, representing under clear-sky condition (“clear” inversion), cloudy with clouds layer top (“cloud-I” without (“cloud-II” inversion). Obvious seasonality...

We investigated the residual rate and mass loss of litter, as well carbon release dynamics litter soil across seasons, to better understand effects seasonal fluctuations on in mixed coniferous forests. The study was carried out natural forests Xiaoxinganling region Heilongjiang Province, China, number temperature cycles unfrozen season, freeze-thaw frozen thaw season controlled. goal examine how respond process whether there are differences under different seasons. Repeated-measures analysis...

In perennially frozen or seasonally soil regions, freeze-thaw cycling adversely impacts the mechanical properties of rock mass, resulting in landslides, erosion, and other geological disasters. The microscopic damage evolution law loaded sandstone under cycle is analyzed by conducting Nuclear Magnetic Resonance (NMR) uniaxial compression acoustic emission (AE) experiments. experimental results have shown that: (1) Freeze-thaw increases sandstone's internal pores, enlarges pore size, modifies...

The lateral unloading strength and deformation of surrounding frozen rock are the key parameters for safety evaluation shaft construction. A low‐temperature high‐pressure triaxial test system was used to simulate freezing construction, a constant axial pressure confining carried out on sandstone. effects temperature, initial pressure, rate strength, deformation, failure modes sandstone studied. main results study as follows: (1) under 20 MPa, temperature decreases from 20°C –5°C, peak stress...

Rainfall data is useful in many fields such as urban management, agriculture, and so on. Spatial interpolation widely used to continue rainfall from discrete gauges. The uncertainty spatial change different region. Paper focus on small area of Beijing city, Xicheng District analyses four aspects: gauge number, density, position, methods. RMSE cross-validation adopted evaluate the accuracy lowest taken optimal. results suggest that more gauges can get a good performance with low error...

Hyperspectral image target recognition, as an important component of computer vision, has broad application prospects in the military field. We conducted research on hyperspectral recognition technology based deep learning, with typical targets main objects. A algorithm suitable for images is proposed YOLO network model. To address issue not being sensitive enough to small targets, calculation formula loss function been adjusted, and a multi-scale training method added. In response...

Ulva prolifera is a new type of marine ecological disaster in China. Since 2007, macroalgal blooms occurred every summer the Yellow Sea and East China Sea, causing significant environmental damage economic loss especially for coastal areas. Because its distribution range covering tens thousands square kilometers during outbreak, it's obviously difficult to monitor using ship, therefore author this article attempted use remote sensing technology temporal spatial distribution.In present study,...