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Phanerozoic co-evolution of O2-CO2 and ocean habitability

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National Science Review 2024年第6期11卷 18-21页

作者： Zunli Lu Rosalind E.M.Rickaby Jonathan L.Payne Ashley N.Prow department of earth & Environmental sciences Syracuse University department of earth sciences University of Oxford department of earth and Planetary sciences Stanford University

atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of earth have been hotly debated, but are generally considered independently.

关键词： CO2-CONCENTRATING MECHANISM OXYGEN EVOLUTION ANOXIA

Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection

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Journal of Environmental sciences 2024年第4期138卷 585-596页

作者： Weijie Yao Xiaole Pan Yu Tian Hang Liu Yuting Zhang Shandong Lei Junbo Zhang Yinzhou Zhang LinWu Yele Sun Zifa Wang State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the *** SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per *** SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal *** sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed *** calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size *** performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring *** instrument could provide useful data for source appointment and regulations against air pollution.

关键词： Instrument development Single particle detection Measurement uncertainty Optical simulation Mass concentration

Co-seismic surface displacement of the June 21, 2022 M_(W)6 Khōst,Afghanistan earthquake from InSAR observations

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Geodesy and Geodynamics 2024年第3期15卷 201-208页

作者： Prohelika Dalal Batakrushna Senapati Bhaskar Kundu department of earth and atmospheric sciences National Institute of TechnologyRourkelaOdisha 769008India

A robust estimation of the earthquake location, seismic moment, and fault geometry is essential for objective seismic hazard assessment. Seismic events in a remote location, specifically in the absence of seismic and GNSS networks, can be investigated effectively using the In SAR-based technique. This study adopts the Differential Interferometric SAR(DIn SAR) technique to quantify the co-seismic surface displacement caused by the June 21, 2022, Khōst M_(W)6 earthquake that occurred along the western plate boundary between the Indian and Eurasian plate. The interferograms show that the maximum surface deformation occurred on the northwest and southwest of the fault line. From coherence, the Line of Sight(LOS) displacement, and the co-seismic surface displacement analysis, it has been observed that surface deformation was most pronounced in the southwest region of the fault line, and the surface has moved to the opposite direction along the fault line, which indicates a sinistral slightly oblique strike-slip movement. This In SAR-based observation appears consistent with the seismic waveforms derived from co-seismic surface displacements. Further, it has been argued that the slip deficit accumulated during the period of the last about 48 years along the frontal region of the northward extension of the Suleiman range and associated fault zone is qualitatively estimated at about 1.5 m, which is consistent with the seismic waveforms derived finite slip model.

关键词： Seismic hazard Khōst earthquake DInSAR Slip deficit LOS displacement Finite slip model

Development of an automatic measurement system using atmospheric pressure photoionization ultrahigh-resolution mass spectrometry and application for on-line analysis of particulate matter

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Journal of Environmental sciences 2024年第4期138卷 516-530页

作者： Yayuan Dong Ranran Liu Ling Xie Xiaole Pan Yele Sun Lin Wu ZifaWang State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional atmospheric Environment Chinese Academy of SciencesInstitute of Urban EnvironmentXiamen 361021China

On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real *** we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS *** formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 *** a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the *** automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 *** detected organic compounds comprised mainly CHON and CHN compounds below 350 m/*** seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in *** result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in *** variation in signal intensity of each formula provides crucial information to reveal its source and formation *** summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5).

关键词： PM_(2.5) Chemical composition On-line measurement technique High resolution mass spectrometry

Science and reflections: With some thoughts to young applied scientists and engineers

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earthquake Science 2024年第5期37卷 459-493页

作者： Robert L Nowack department of earth Atmospheric and Planetary SciencesPurdue UniversityWest LafayetteIN47906USA

I provide some science and reflections from my experiences working in geophysics,along with connections to computational and data sciences,including recent developments in machine learning.I highlight several individuals and groups who have influenced me,both through direct collaborations as well as from ideas and insights that I have learned *** my reflections are rooted in geophysics,they should also be relevant to other computational scientific and engineering fields.I also provide some thoughts for young,applied scientists and engineers.

关键词： geophysics computational and data science applied science and engineering

Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory J.Retallack department of earth sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Enhanced Cooling Efficiency of Urban Trees on Hotter Summer Days in 70 Cities of China

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Advances in atmospheric sciences 2024年第11期41卷 2259-2275页

作者： Limei YANG Jun GE Yipeng CAO Yu LIU Xing LUO Shiyao WANG Weidong GUO School of atmospheric sciences Nanjing UniversityNanjing 210023China Joint International Research Laboratory of atmospheric and earth System sciences Nanjing UniversityNanjing 210023China Frontiers Science Center for Critical earth Material Cycling Nanjing UniversityNanjing 210023China

Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter days, depending on the physiological response of urban trees to rising ambient temperature. However, the response of urban trees' cooling efficiency to rising urban temperature remains poorly quantified for China's cities. In this study, we quantify the response of urban trees' cooling efficiency to rising urban temperature at noontime [~1330 LT(local time), LT=UTC+8] in 17summers(June, July, and August) from 2003–19 in 70 economically developed cities of China based on satellite observations. The results show that urban trees have stronger cooling efficiency with increasing temperature, suggesting additional cooling benefits provided by urban trees on hotter days. The enhanced cooling efficiency values of urban trees range from 0.002 to 0.055℃ %-1 per 1℃ increase in temperature across the selected cities, with larger values for the lowTCP-level cities. The response is also regulated by background temperature and precipitation, as the additional cooling benefit tends to be larger in warmer and wetter cities at the same TCP level. The positive response of urban trees' cooling efficiency to rising urban temperature is explained mainly by the stronger evapotranspiration of urban trees on hotter *** results have important implications for alleviating urban heat risk by utilizing urban trees, particularly considering that extreme hot days are becoming more frequent in cities under global warming.

关键词： urban trees cooling efficiency China's cities evapotranspiration summer hot days

A high-resolution dataset for lower atmospheric process studies over the Tibetan Plateau from 1981 to 2020

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Big earth Data 2024年第3期8卷 540-565页

作者： Fei Li Shupo Ma Jinhuan Zhu Han Zou Peng Li Libo Zhou department of Lower atmospheric Observation Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina

ABSTRACT A high-resolution meteorological dataset(≤10 km)over the Tibetan Plateau(TP)is the foundation for investigating and predicting the weather and climate over *** TP Subregional Dynamical Downscaling(TPSDD)dataset is a newly developed high-spatial-temporal resolution gridded dataset for land‒air exchange pro-cesses and lower atmospheric structure studies over the whole TP region,taking the climate characteristics of each TP subregion into *** dataset spans from 1981 to 2020,covering the TP with a temporal resolution of 2 hr and spatial resolution of 10 *** elements of the dataset include near-surface land-air exchange parameters,such as downward/upward long-wave/shortwave radiation flux,sensible heat flux,latent heat flux,*** addition,the vertical distributions of 3-dimensional wind,temperature,humidity,and pressure from the surface to the lower stratosphere are also *** evaluations were con-ducted to verify the performance of the TPSDD dataset by compar-ing TPSDD/reanalysis with surface and vertical observations through the calculation of statistical *** results demonstrate the accuracy and superiority of this dataset against reanalysis data,which provides great potential for future climate change research.

关键词： Tibetan Plateau WRF model dynamical downscaling land‒air interaction the lower atmosphere

Quantitative estimation of global mean precipitation throughout the Phanerozoic era

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Science China earth sciences 2024年第5期67卷 1616-1624页

作者： Xiujuan BAO Yongyun HU Laboratory for Climate and Ocean-atmospheric Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China

Quantitatively estimating the global mean precipitation(GMP)throughout earth's history is crucial for enhancing our understanding of long-term climate evolution and the hydrological ***,currently there is no established methodology for estimating global mean ***,we present the first study that estimates GMP in the Phanerozoic *** relationship between GMP and global mean surface temperature(GMST)is investigated by analyzing data from 23 models in the Coupled Model Intercomparison Project phase 6(CMIP6).The result reveals consistent and significant impact of temperature on precipitation,with a sensitivity range of 2–3%K^(-1).Additionally,we propose a method for accessing latitudinal variations in precipitation caused by land area distributions and paleo-Koppen climatic *** climatic belts are determined based on geological indicators such as coals,evaporites,and glacial *** GMP is thus quantitatively estimated by combining variations in GMST,land area distributions,and paleo-koppen climatic belts,spanning from 540 Ma to the present *** quantitative GMP curve demonstrates fluctuations in GMP about 500 mm yr^(-1),with values ranging from 948 to1442 mm yr-1over the Phanerozoic *** curve aligns closely with findings derived from numerical *** presented paleoprecipitation variations facilitate a more comprehensive understanding of the interconnected geological and paleoclimatic developments.

关键词： Paleoprecipitation Paleoclimate K?ppen climatic belts Global mean precipitation Hydrological cycle