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Toward Sustainable Revegetation in the Loess Plateau Using Coupled Water and Carbon management

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Engineering 2022年第8期8卷 143-153页

作者： Fubo Zhao Yiping Wu Xiaowei Yin Georgii Alexandrov Linjing Qiu Department of Earth and Environmental Science School of Human Settlements and Civil EngineeringXi’an Jiaotong UniversityXi’an 710049China A.M.Obukhov Institute of Atmospheric Physics Russian Academy of SciencesMoscow 119017Russia

The"Grain-for-Green"project on the Loess Plateau is the largest revegetation program in the world.However,revegetation-induced land use changes can influence both water and carbon cycles,and the diverse consequences were not well understood.Therefore,the reasonability and sustainability of revegetation measures are in question.This study quantifies the impacts of revegetation-induced land use conversions on the water and carbon cycles in a typical watershed on the Loess Plateau and identifies suitable areas where revegetation of forest or grassland could benefit both soil and water conservation and carbon sequestration.We used a coupled hydro-biogeochemical model to simulate the changes of a few key components in terms of water and carbon by designing a variety of hypothetical land use conversion scenarios derived from revegetation policy.Compared to the baseline condition(land use in 2000),both sediment yield and water yield decreased substantially when replacing steep cropland with forest or grassland.Converting cropland with slopes larger than 25°,15°,and 6°to forest(CTF)would enhance the carbon sequestration with a negligible negative effect on soil water content,while replacing cropland with grassland(CTG)would result in a decline in net primary production but with a substantial increase in soil water content(3.8%-14.9%).Compared to the baseline,the soil organic carbon would increase by 0.9%-3.2% in CTF and keep relatively stable in CTG.Through testing a variety of hypothetical revegetation scenarios,we identified potential priority areas for CTF and CTG,where revegetation may be appropriate and potentially beneficial to conserving soil and water and enhancing carbon sequestration.Our study highlights the challenges in future water and carbon coupling management under revegetation policy,and our quantitative results and identification of potential areas for revegetation could provide information to policy makers for seeking optimal management on the Loess Plateau.

关键词： Carbon Land use change Loess Plateau Sediment SWAT-Day Cent Water resources

Tropical Cyclones and Polar Lows: Velocity, Size, and Energy Scales, and Relation to the 26℃ Cyclone Origin Criteria

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Advances in atmospheric Sciences 2009年第3期26卷 585-598页

作者： G.S.GOLITSYN A.M.Obukhov Institute of Atmospheric Physics Russian Academy of SciencesMoscow 119017Russian Federation

The goal of this paper is to quantitatively formulate some necessary conditions for the development of intense atmospheric vortices. Specifically, these criteria are discussed for tropical cyclones （TC） and polar lows （PL） by using bulk formulas for fluxes of momentum, sensible heating, and latent heating between the ocean and the atmosphere. The velocity scale is used in two forms：（1） as expressed through the buoyancy flux b and the Coriolis parameter Ic for rotating fluids convection, and （2） as expressed with the cube of velocity times the drag coefficient through the formula for total kinetic energy dissipation in the atmospheric boundary layer. In the quasistationary case the dissipation equals the generation of the energy. In both cases the velocity scale can be expressed through temperature and humidity differences between the ocean and the atmosphere in terms of the reduced gravity, and both forms produce quite comparable velocity scales. Using parameters b and Ic, we can form scales of the area and, by adding the mass of a unit air column, a scale of the total kinetic energy as well. These scales nicely explain the much smaller size of a PL, as compared to a TC, and the total kinetic energy of a TC is of the order 1018 - 1019 J. It will be shown that wind of 33 m s^-1 is produced when the total enthalpy fluxes between the ocean and the atmosphere are about 700 W m-2 for a TC and 1700 W m-2 for a PL, in association with the much larger role of the latent heat in the first case and the stricter geostrophic constraints and larger static stability in the second case. This replaces the mystical role of 26℃ as a criterion for TC origin. The buoyancy flux, a product of the reduced gravity and the wind speed, together with the atmospheric static stability, determines the rate of the penetrating convection. It is known from the observations that the formation time for a PL reaching an altitude of 5-6 km can be only a few hours, and a day, or even half a day, for a TC reaching 15-18 km. These two facts allow u

关键词： typhoons polar lows velocity size and energy scales cyclone origin criteria

Long-Term Trends of Carbon monoxide Total Columnar Amount in Urban Areas and Background Regions:Ground-and Satellite-based Spectroscopic measurements

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Advances in atmospheric Sciences 2018年第7期35卷 785-795页

作者： Pucai WANG N.F.ELANSKY Yu.m.TImOFEEV Gengchen WANG G.S.GOLITSYN m.V.mAKAROVA V.S.RAKITIN Yu.SHTABKIN A.I.SKOROKHOD E.I.GRECHKO E.V.FOKEEVA A.N.SAFRONOV Liang RAN Ting WANG LAGEO Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China A.M.Obukhov Institute of Atmospheric Physics Russian Academy of SciencesMoscow 119017Russia St.Petersburg State University Saint-Petersburg 198904Russia

A comparative study was carried out to explore carbon monoxide total columnar amount（CO TC） in background and polluted atmosphere, including the stations of ZSS（Zvenigorod）, ZOTTO（Central Siberia）, Peterhof, Beijing, and moscow,during 1998–2014, on the basis of ground-and satellite-based spectroscopic measurements. Interannual variations of CO TC in different regions of Eurasia were obtained from ground-based spectroscopic observations, combined with satellite data from the sensors mOPITT（2001–14）, AIRS（2003–14）, and IASI met Op-A（2010–13）. A decreasing trend in CO TC（1998–2014） was found at the urban site of Beijing, where CO TC decreased by 1.14% ± 0.87% yr^（-1）. meanwhile, at the moscow site, CO TC decreased remarkably by 3.73% ± 0.39% yr^（-1）. In the background regions（ZSS, ZOTTO, Peterhof）, the reduction was 0.9%–1.7% yr^（-1） during the same period. Based on the AIRSv6 satellite data for the period 2003–14, a slight decrease（0.4%–0.6% yr^（-1）） of CO TC was detected over the midlatitudes of Eurasia, while a reduction of 0.9%–1.2% yr^（-1） was found in Southeast Asia. The degree of correlation between the CO TC derived from satellite products（mOPITTv6 Joint, AIRSv6 and IASI met Op-A） and ground-based measurements was calculated, revealing significant correlation in unpolluted regions.While in polluted areas, IASI met Op-A and AIRSv6 data underestimated CO TC by a factor of 1.5–2.8. On average, the correlation coefficient between ground-and satellite-based data increased significantly for cases with PBL heights greater than 500 m.

关键词： carbon monoxide trend spectroscopic measurement mOPITT AIRS IASI

Uncertainty of Climate Response to Natural and Anthropogenic Forcings Due to Different Land Use Scenarios

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Advances in atmospheric Sciences 2011年第5期28卷 1215-1232页

作者： Alexey V.ELISEEV Igor I.mOKHOV A. m. obukhov institute of atmospheric physics Russian Academy of Sciences3 Pyzhevsky 119017 Moscow Russia

The A.M.Obukhov Institute of Atmospheric Physics,Russian Academy of Sciences （IAP RAS） climate model （Cm） of intermediate complexity is extended by a spatially explicit terrestrial carbon cycle module.Numerical experiments with the IAP RAS Cm are performed forced by the reconstructions of anthropogenic and natural forcings for the 16th to the 20th centuries and by combined SRES （Special Report on Emission Scenarios） A2-LUH （Land Use Harmonization） anthropogenic scenarios for the 21st century.Hereby,the impact of uncertainty in land-use scenarios on results of simulations with a coupled climate-carbon cycle model is tested.The simulations of the model realistically reproduced historical changes in carbon cycle characteristics.In the IAP RAS Cm,climate warming reproduced in the 20th and 21st centuries enhanced terrestrial net primary production but terrestrial carbon uptake was suppressed due to an overcompensating increase in soil respiration.Around year 2100,the simulations the model forced by different land use scenarios diverged markedly,by about 70 Pg （C） in terms of biomass and soil carbon stock but they differed only by about 10 ppmv in terms of atmospheric carbon dioxide content.

关键词： terrestrial carbon cycle climate model anthropogenic scenarios uncertainty in projections

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Journal of modern physics 2012年第10期3卷 1523-1529页

作者： Georgy S. Golitsyn A. m. obukhov institute of atmospheric physics Russian Academy of Sciences Moscow Russia

An old topic of dimensional analysis in astrophysics is presented and new results, or quantitative explanations of some observational facts are obtained, in particular, on the base of the supernova, SN, explosions. The presentation starts with the derivation of two similarity criteria for astrophysical objects constructed out of four measurable quantities: mass, m, luminosity, Lb, velocity U, size R, and gravitational constant G. The first well known criterium describes the virial principle and the other one seems to be new and is based on the Tully-Fisher observational relationship between luminosity and velocity. The energy generated by SN explosions allows one to estimate well the interstellar turbulent velocities and magnetic field in our Galaxy, resulting in 3 to 4 microgauss. It is found that for z ≥ 0.6 the observed distant galactic clusters are far from virial equilibrium and the degree of disequilibrium is increasing with z. It means that to reach such an equilibrium the cluster age should be of order ten dynamical time scales, see Equation (7). For all considered galaxy clusters the second similarity criterium was found to be constant with a precision of about ten per cent. Therefore it could be considered as a general law, though for different classes of objects the numerical coefficient may vary. Some scales are proposed and two of them are tested for galactic clusters by finding numerical coefficients with accuracies of about 20 percent or better: e.g. observed luminocities of clusters are W=Lb=a1(m/R)5/2G3/2 with for the first eleven objects from the Table for which the virial equilibrium is found with the same accuracy. The square root of the two criteria ratio 3=( 2/ 1)1/2=U(WG)-1/5 explains the Tully-Fisher law and is constant for all 32 available clusters from [1,2] and is equal to 1.8 ± 0.2. This is because 3 has not global values of total mass and size.

关键词： Dimensional Analysis Galaxy Clusters Virial Evolution Tully-Fisher Law Turbulence and magnetic Fields

atmospheric and Coupled model Intercomparison in Terms of Amplitude—Phase Characteristics of Surface Air Temperature Annual Cycle

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Advances in atmospheric Sciences 2004年第6期21卷 837-847页

作者： Alexey V. ELISEEV Igor I. mOKHOV Konstantin G. RUBINSTEIN maria S. GUSEVA A. m. obukhov institute of atmospheric physics RAS 3 Pyzhevsky 119017 Moscow RussiaA. M. Obukhov Institute of Atmospheric Physics RAS 3 Pyzhevsky 119017 Moscow RussiaRussian Hydrometcentre 9 Bol. Predtechensky 123242 Moscow RussiaRussian Hydrometcentre 9 Bol. Predtechensky 123242 Moscow Russia

A model intercomparison in terms of surface air temperature annual cycle amplitude-phase characteristics (SAT AC APC) is performed. The models included in the intercomparison belong to two groups: five atmospheric models with prescribed sea surface temperature and sea ice cover and four coupled models forced by the atmospheric abundances of anthropogenic constituents (in total six coupled model simulations). Over land, the models, simulating higher than observed time averaged SAT, also tend to simulate smaller than observed amplitude of its annual and semiannual harmonics and (outside the Tropics) later-than-observed spring and autumn moments. The models with larger (smaller) time averaged amplitudes of annual and semiannual harmonics also tend to simulate larger (smaller) interannual standard deviations. Over the oceans, the coupled models with larger interannual standard deviations of annual mean SAT tend to simulate larger interannual standard deviations of both annual and semiannual SAT harmonics amplitudes. most model errors are located in the belts 60°–70°N and 60°–70°S and over Antarctica. These errors are larger for those coupled models which do not employ dynamical modules for sea ice. No systematic differences are found in the simulated time averaged fields of the surface air temperature annual cycle characteristics for atmospheric models on one hand and for the coupled models on the other. But the coupled models generally simulate interannual variability of SAT AC APC better than the atmospheric models (which tend to underestimate it). For the coupled models, the results are not very sensitive to the choice of the particular scenario of anthropogenic forcing. There is a strong linear positive relationship between the model simulated time averaged semiannual SAT harmonics amplitude and interannual standard deviation of annual mean SAT. It is stronger over the tropical oceans and is weaker in the extratropics. In the tropical oceanic areas, it is stronger for the coupled than for the atmospheric models.

关键词： annual cycle reanalysis data climate model intercomparison

Variations and drivers of aerosol vertical characterization after clean air policy in China based on 7-years consecutive observations

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Journal of Environmental Sciences 2023年第3期125卷 499-512页

作者： Xi Chen Ting Yang Haibo Wang Futing Wang Zifa Wang State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Understanding the aerosol vertical characterization is of great importance to both climate and atmospheric environment. This study investigated the variations of aerosol profiles over eight regions of interest in China after clean air policy(2013-2019) and discussed the drivers of the vertical aerosol structure, using observations from active satellite measurements(CALIPSO). From the annual variation, the amplitude of extinction coefficient profiles showed a decreasing trend with fluctuations, and the maximum was 0.21 km-1in BeijingTianjin-Hebei(JJJ). For regions suffered from air pollution, the variation was greatest below 0.45 km, while it was between 1-1.5 km for Sichuan Basin. The correlation coefficient between the relative humidity(RH) and the extinction coefficient indicated that the increase of RH inhibited the decrease of the extinction coefficient in the Yangtze River Delta. In most regions, the main aerosol subtypes were polluted dust and polluted continental, but they were coarser in JJJ and North West. The frequency of concurrency of dust and polluted dust aerosols decreased in JJJ, but polluted continental aerosols occurred more frequently. Further, the aerosol extinction coefficient profiles under different pollution conditions showed that it changed most during heavy pollution periods in JJJ, especially in 2017, with a significant aerosol loading between700 and 1200 m. The atmospheric reanalysis data revealed that the weak convergence at low level and the divergence at high level supported the upward transport of aerosols in 2017. Overall, the differences in divergence allocation, RH, and wind filed were the main meteorological drivers.

关键词： Aerosol Vertical characteristic China CALIPSO Pollution period

Regional climate response to global warming in the source region of the Yellow River and its impact on runoff

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Science China Earth Sciences 2024年第3期67卷 843-855页

作者： Yiran ZHANG Degang ZHOU Xiaofeng GUO Center for monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The source region of the Yellow River has experienced obvious climate and discharge changes in recent decades due to global warming, which largely affects the water resources and ecological and environmental security in the Yellow River basin. This study analyzed the changes in runoff and several climate factors in the source region of the Yellow River based on the observed discharges at the Tangnag hydrological station, routine meteorological data from China meteorological Administration(CmA) stations within and near this source region, and several evaporation datasets. The results indicate that the runoff in the source region was relatively abundant from 1960 to 1989 and then declined sharply afterward. It recovered slightly after 2005 but was still below normal—10% less than that during 1960–1989. Similarly, the precipitation amounts in the source region were relatively low in the 1990s, but they increased significantly after 2003, with an average increase of 31.4 mm or 6% more when compared to that in 1960–1989. In addition, the temperatures in the source region continued to rise from 1960 to 2017, and the evaporation levels also showed an upward trend after 1990. The influences of the spatial and temporal variations in climatic factors on runoff in the source region were then further analyzed. The results indicate that the decreases in precipitation and the number of days of heavy rainfall in the source region from 1990 to 2002 were important reasons for the lower runoff during this period. After 2003, the precipitation in the southeastern part of the source region, which is a key area for runoff generation,increased only to a limited extent, but the evaporation in the entire source region generally increased with increasing temperature,which might have led to the low capacity for actual runoff production in each subbasin and persistent low runoff in the source region. Therefore, such a climate response to global warming in the source region might be unfavorable for increased runoff in the future. The above

关键词： The source region of the Yellow River Climate response Runoff variation Evaporation Precipitation

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 time.Here we describe the development and application of an automatic measurement system that incorporates Pm_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRmS analysis.molecular 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 pg.As 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 system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In 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