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1.
Monitoring atmospheric carbon dioxide(CO_2) from space-borne state-of-the-art hyperspectral instruments can provide a high precision global dataset to improve carbon flux estimation and reduce the uncertainty of climate projection. Here, we introduce a carbon flux inversion system for estimating carbon flux with satellite measurements under the support of "The Strategic Priority Research Program of the Chinese Academy of Sciences—Climate Change: Carbon Budget and Relevant Issues". The carbon flux inversion system is composed of two separate parts: the Institute of Atmospheric Physics Carbon Dioxide Retrieval Algorithm for Satellite Remote Sensing(IAPCAS), and Carbon Tracker-China(CT-China), developed at the Chinese Academy of Sciences. The Greenhouse gases Observing SATellite(GOSAT) measurements are used in the carbon flux inversion experiment. To improve the quality of the IAPCAS-GOSAT retrieval, we have developed a post-screening and bias correction method, resulting in 25%–30% of the data remaining after quality control. Based on these data, the seasonal variation of XCO_2(column-averaged CO_2dry-air mole fraction) is studied, and a strong relation with vegetation cover and population is identified. Then, the IAPCAS-GOSAT XCO_2 product is used in carbon flux estimation by CT-China. The net ecosystem CO_2 exchange is-0.34 Pg C yr~(-1)(±0.08 Pg C yr~(-1)), with a large error reduction of 84%, which is a significant improvement on the error reduction when compared with in situ-only inversion.  相似文献   

2.
全球大气温度廓线的统计特性分析   总被引：1，自引：0，他引：1  
罗双  尹球 《热带气象学报》2019,35(4):556-566
利用欧洲数值预报中心发布的第三代ERA-Interim月平均再分析资料对1979—2016年全球大气温度廓线进行统计,分别探讨了南、北半球大气温度廓线平均值和标准差随季节、纬度和海陆的时空分布特征,并与国内外常用的AFGL标准大气廓线进行了对比。研究结果表明:南、北半球各高度层温度的平均值、频数最大温度区间和最大值垂直分布均随高度先减小后增加;在大气低层,多年的温度波动较大,200 hPa处波动达到最小;不论是北半球还是南半球,大气温度平均值廓线均具有典型的纬度差异,其中低纬度季节性差异较小,中纬度次之,高纬季节性差异最大;各季节大气温度廓线的海陆差异不同,且南半球海陆差异比北半球大。大气温度标准差廓线同样存在纬度、海陆和季节分布差异。根据ECMWF再分析资料构建的温度廓线较AFGL标准大气廓线而言具有更加丰富的时空分布等细节特征,并且代表了气候变化后最新的大气温度状况。有关结果可作为现有标准大气廓线的更新和完善,为新型卫星仪器应用性能评估、辐射传输算法和大气反演方法评价和对比分析提供支持。   相似文献   

3.
通过卫星观测光谱反演计算是当前观测全球CO2浓度水平,分析其变化趋势的重要手段,但是由于观测条件及反演方法的限制,基于卫星观测光谱反演计算只能得到离散的CO2浓度数据,需要借助空间插值方法才能获得空间连续的CO2浓度数据。本文以SCIAMACHY研究团队发布的XCO2浓度数据为基础数据,首先对比分析了空间分析中常用的3种经典插值方法（反距离加权法,克里格法,样条函数法）在XCO2空间内插中的精度,综合分析平均绝对值误差、绝对值误差最大值和均方根误差3个指标,结果表明反距离加权插值法为最优内插方法。基于该方法生成2003年1月-2012年4月共计112个月的全球大陆XCO2浓度分布数据集,并对全球大陆范围内XCO2浓度的时空变化特征进行分析,发现在此时段内全球各个大陆XCO2均表现出增加的趋势;在全球大陆平均水平上,XCO2浓度增加幅度为17.43×10-6,XCO2年平均值增加速率约为2×10-6,总体上呈现北半球增加速率高于南半球的特点。  相似文献   

4.
利用TERRA/MOPITT仪器测量的2000年3月—2004年5月的CO数据, 分析了CO的时空分布特征及其变化趋势, 并且与美国国家海洋大气管理局气候监测与诊断实验室 (CMDL/NOAA) 在瓦里关站的CO观测结果进行比较和验证。结果表明: CO的高值区在北半球主要位于东亚、西欧和北美, 而在南半球主要位于非洲中西部和南美洲的赤道地区; CO的分布随季节变化显著, 春季北半球的CO浓度最高, 而秋季南半球的CO浓度偏高; 东亚的CO高值区主要是位于中国东部沿海地区和日本列岛一带。对于北京和瓦里关CO的趋势分析明表:这两个地区的CO浓度在这4年内都是呈上升趋势。结合CMDL的观测资料与卫星观测结果进行比较和检验发现, 瓦里关站卫星观测结果和CMDL的结果在时间序列的变化趋势一致, 卫星柱总量的观测数据和CMDL数据的相关性非常好。  相似文献   

5.
The 1st Chinese carbon dioxide(CO2)monitoring satellite mission,TanSat,was launched in 2016.The 1st TanSat global map of CO2 dry-air mixing ratio(XCO2)measurements over land was released as version 1 data product with an accuracy of 2.11 ppmv(parts per million by volume).In this paper,we introduce a new(version 2)TanSat global XCO2 product that is approached by the Institute of Atmospheric Physics Carbon dioxide retrieval Algorithm for Satellite remote sensing(IAPCAS),and the European Space Agency(ESA)Climate Change Initiative plus(CCI+)TanSat XCO2 product by University of Leicester Full Physics(UoL-FP)retrieval algorithm.The correction of the measurement spectrum improves the accuracy(?0.08 ppmv)and precision(1.47 ppmv)of the new retrieval,which provides opportunity for further application in global carbon flux studies in the future.Inter-comparison between the two retrievals indicates a good agreement,with a standard deviation of 1.28 ppmv and a bias of?0.35 ppmv.  相似文献   

6.
East China (23.6°–38.4°N, 113.6°–122.9°E) is the largest developed region in China. Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite (GOSAT), the spatial and temporal distributions of CO2 mixing ratios in East China during 2014–17 are discussed, and the retrieved CO2 from AIRS (Atmospheric Infrared Sounder) and OCO-2 (Orbiting Carbon Observatory-2), as well as WLG (Waliguan) background station observations, are compared with those of GOSAT. The annual CO2 retrieved from GOSAT in East China ranged from 398.96 ± 0.24 ppm in 2014 to 407.39 ± 0.20 ppm in 2017, with a growth rate of 2.82 ± 0.15 ppm yr?1, which were higher than in other regions of China. The seasonal cycle presented a maximum in spring and a minimum in summer or autumn. Higher values were mainly concentrated in the coastal areas of Zhejiang Province, and lower values were concentrated in Jiangxi and the north of Fujian Province. CO2 observed in Fujian and parts of Jiangxi increased by less than 1.0 ppm during 2014–15, but enhanced significantly by more than 5.0 ppm during 2015–16, perhaps influenced by local emissions and global impacts. We calculated year-to-year CO2 enhancements in the Yangtze River Delta region during 2014–17 that were relatively low and stable, due to the region’s carbon emissions control and reduction policies. The annual and seasonal amplitudes of CO2 retrieved from AIRS were lower than those from GOSAT in East China, probably owing to the CO2 retrieved from AIRS better reflecting the characteristics of the mid-troposphere, while GOSAT is more representative of near-surface CO2. The spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to those from GOSAT in East China.  相似文献   

7.
The results of a research study of the carbon monoxide concentration from California to 90° S, Antarctica are presented. The data both extend and support other research studies of the latitudinal distribution of carbon monoxide in that higher concentrations are evident over the Northern Hemisphere than over the Southern Hemisphere. Carbon monoxide concentrations range between 50 to 60 ppb with a few peaks into the 60s in the latitudinal area south of the ITCZ and values of 80 ppb or higher at latitudes north of Hawaii. A comparison is also made of carbon monoxide and ozone concentrations along the flight tract between California and Antarctica, over the Ellsworth Mountains of Antarctica, and between 78° S and the South Pole. These ozone-carbon monoxide data show statistically significant negative correlations in the upper troposphere and lower stratosphere over Antarctica. It is believed that this is a good indication of mixing across the tropopause.  相似文献   

8.
 The Louvain-la-Neuve climate model (here referred to as the LLN 2-D model has been used extensively to simulate the Northern Hemisphere ice volume under both the insolation and CO2 forcings. The period analysed here covers the last 200 ky. First, sensitivity analyses to constant CO2 concentration were performed. The model was accordingly forced by insolation changes only, the CO2 concentration being kept constant to respectively 210, 250 and 290 ppmv. Results show that the simulated ice volume variations are comparable to the geological reconstructions only when the CO2 concentration is low (210 ppmv) and that the sensitivity of the simulated Northern Hemisphere ice volume to CO2 is not constant through time. Second, three CO2 reconstructions were used to force the LLN 2-D model in addition to insolation. Results show (1) a better agreement with the SPECMAP oxygen isotope time series, in particular as far as the amplitude of the signal is concerned, and (2) that the simulated Northern Hemisphere ice volume is not very sensitive to the slight differences between these three reconstructions.  相似文献   

9.
利用TCCON网站提供的北半球7个地面观测站CO2干空气混合比（XCO2）数据,对3种卫星反演的XCO2产品进行了验证,包括SCIAMACHY产品、NIES-GOSAT产品和ACOS-GOSAT产品。结果表明：卫星CO2遥感反演产品与地基遥感资料具有较一致的季节性周期变化,一年中月平均浓度最高值均出现在4月和5月,最低值均出现在8月和9月;相对于地面观测,3种卫星产品均低估了XCO2;ACOS-GOSAT产品与NIES-GOSAT产品的精度大体相当,误差标准差分别为2.26×10-6和2.27×10-6;SCIAMACHY产品的精度略差,误差标准差为2.91×10-6。  相似文献   

10.
During the cruise ANT VII/1 (September/October 1988) of the German research vessel Polarstern the latitudinal distributions of several nonmethane hydrocarbons were measured over the Atlantic between 45°N and 30°S by in-situ gas chromatography.On the average, the highest mixing ratios of ethane, propane, i- and n-butane, ethene and acetylene were observed in the Northern Hemisphere around 40° N and just north of the intertropical convergence zone, respectively. South of the equator, a bulge in the mixing ratios of ethane and acetylene was observed indicating aged biomass burning emissions. This observation coincided with enhanced tropospheric ozone found in this region at this season. On the average ethane and acetylene mixing ratios were around 500 and 100 ppt, respectively, whereas the levels of the other NMHC were in the range of some ppt up to 100 ppt.compared with the results of the cruise ANT V/5 (March/April, 1987), the ethane mixing ratios in September/October proved to be a factor of 3 lower in the Northern Hemisphere and a factor of 2 higher in the Southern Hemisphere, probably due to seasonal effects. Possible causes are the higher OH radical concentrations in summer, which result in a faster removal of ethane or stronger emission from biomass burning which also peaks in the dry season.The relative pattern of the hydrocarbons just north of the ITCZ was very similar for both measurement series. In this region, the NMHC were advected by long-range transport from the continent, whereas generally the ocean itself acts as a major NMHC source. This is supported by the results of a balance calculation between oceanic emissions and atmospheric removal rates.  相似文献   

11.
Abstract The spatial and temporal variations of atmospheric CO2 at 8–13 km from April 1993 to April 1999 were observed by measuring CO2 mixing ratios in samples collected biweekly from a commercial airliner between Australia and Japan. The CO2 growth rate showed a considerable interannual variation, with a maximum of about 3 ppm yr−1 during late 1997. This variation is related to the El Niño/Southern Oscillation (ENSO) events. A year-to-year change related to the ENSO events was also found in the latitudinal distribution pattern of the CO2 annual mean between 30°N and 30°S. The averaged CO2 seasonal cycle in the Northern Hemisphere gradually decayed toward the equator, and a relatively complicated variation with a double seasonal maximum appeared in the Southern Hemisphere. A significant yearly change of the seasonal cycle pattern was observed in the Southern Hemisphere. The impact of a tropical biomass-burning injection on the upper tropospheric CO2 was estimated on the basis of the CO data from the same airliner observation.  相似文献   

12.
Space-borne measurements of atmospheric greenhouse gas concentrations provide global observation constraints for top-down estimates of surface carbon flux.Here,the first estimates of the global distribution of carbon surface fluxes inferred from dry-air CO_2 column (XCO_2) measurements by the Chinese Global Carbon Dioxide Monitoring Scientific Experimental Satellite (Tan Sat) are presented.An ensemble transform Kalman filter (ETKF) data assimilation system coupled with the GEOS-Chem global chemistry transport model is used to optimally fit model simulations with the Tan Sat XCO_2 observations,which were retrieved using the Institute of Atmospheric Physics Carbon dioxide retrieval Algorithm for Satellite remote sensing (IAPCAS).High posterior error reduction (30%–50%) compared with a priori fluxes indicates that assimilating satellite XCO_2 measurements provides highly effective constraints on global carbon flux estimation.Their impacts are also highlighted by significant spatiotemporal shifts in flux patterns over regions critical to the global carbon budget,such as tropical South America and China.An integrated global land carbon net flux of 6.71±0.76 Gt C yr~(-1) over12 months (May 2017–April 2018) is estimated from the Tan Sat XCO_2 data,which is generally consistent with other inversions based on satellite data,such as the JAXA GOSAT and NASA OCO-2 XCO_2 retrievals.However,discrepancies were found in some regional flux estimates,particularly over the Southern Hemisphere,where there may still be uncorrected bias between satellite measurements due to the lack of independent reference observations.The results of this study provide the groundwork for further studies using current or future Tan Sat XCO_2 data together with other surfacebased and space-borne measurements to quantify biosphere–atmosphere carbon exchange.  相似文献   

13.
为了深入了解国际上新一代CO2等温室气体的空间观测计划及进展情况,以日本和美国于2009年最新发射的温室气体测卫星呼吸号(GOSAT)、轨道碳观测者(OCO)为例,分析了观测计划的开展情况,对卫星上搭载的传感器设置做了分析,对新一代温室气体专用观测卫星与传统卫星上的传感器做了对比,得出了新一代的传感器在设置上的特点:波段设置在近红外太阳辐射以获得边界层的温室气体含量,具有高的光谱分辨率以保证观测精度,多种观测方式结合以获得最大的信息量。并提出了我国应对温室气体观测资料缺乏的对策,发展专用观测卫星或传感器,以提供我们自己的高精度的全球和区域温室气体观测数据。  相似文献   

14.
为了深入了解国际上新一代CO2等温室气体的空间观测计划及进展情况,以日本和美国于2009年最新发射的温室气体测卫星＂呼吸＂号（GOSAT）、＂轨道碳观测者＂（OCO）为例,分析了观测计划的开展情况,对卫星上搭载的传感器设置做了分析,对新一代温室气体专用观测卫星与传统卫星上的传感器做了对比,得出了新一代的传感器在设置上的特点：波段设置在近红外太阳辐射以获得边界层的温室气体含量,具有高的光谱分辨率以保证观测精度,多种观测方式结合以获得最大的信息量。并提出了我国应对温室气体观测资料缺乏的对策,发展专用观测卫星或传感器,以提供我们自己的高精度的全球和区域温室气体观测数据。  相似文献   

15.
An analysis of simulated global water-balance components (precipitation [P], actual evapotranspiration [AET], runoff [R], and potential evapotranspiration [PET]) for the past century indicates that P has been the primary driver of variability in R. Additionally, since about 2000, there have been increases in P, AET, R, and PET for most of the globe. The increases in R during 2000 through 2009 have occurred despite unprecedented increases in PET. The increases in R are the result of substantial increases in P during the cool Northern Hemisphere months (i.e. October through March) when PET increases were relatively small; the largest PET increases occurred during the warm Northern Hemisphere months (April through September). Additionally, for the 2000 through 2009 period, the latitudinal distribution of P departures appears to co-vary with the mean P departures from 16 climate model projections of the latitudinal response of P to warming, except in the high latitudes. Finally, changes in water-balance variables appear large from the perspective of departures from the long-term means. However, when put into the context of the magnitudes of the raw water balance variable values, there appears to have been little change in any of the water-balance variables over the past century on a global or hemispheric scale.  相似文献   

16.
A new gas chromatographic technique with a modified photoionization detector connected in series with a conventional flame ionization detector was used to determine low concentrations of atmospheric hydrocarbons in remote atmospheres. Average mixing ratios of five aromatic hydrocarbons measured between 42°N and 30°S latitude in the Pacific Ocean in October/November 1983 were highest in the Northern Hemisphere. The average mixing ratios in the northern and southern marine atmospheres were 49±25 ppt (n=35) and 10±2 ppt (n=21) for benzene, 20±12 ppt (n=32) and 5.6±1.6 ppt (n=12) for toluene, 7.6±3.7 ppt (n=35) and 3.7±1.6 ppt (n=21) for ethylbenzene, 25±12 ppt (n=35) and 13±5 ppt (n=20) for the sum of m- and p-xylenes, and 14±6 ppt (n=35) and 6.6±3.0 ppt (n=21) for o-xylene, respectively. The first latitudinal gradients for these five aromatic compounds are reported. Benzene and toluene mixing ratios measured between July 1982 and October 1983 at a rural, mid-latitude continental site in eastern Washington state gave average values of 226±108 ppt and 133±84 ppt, respectively, with higher wintertime than summertime benzene levels. These continental samples gave calculated air mass ages averaging six days based on benzene-to-toluene ratios.  相似文献   

17.
A latitudinal profile (30° W, from 30° N to 30° S) of mixing ratios of nitric acid and particulate nitrate was determined on the Atlantic Ocean during the Polarstern cruise ANT VII/1 from Bremerhaven, Germany, to Rio Grande, Brazil. The detection of HNO3 was performed simultaneously by laser-photolysis fragment-fluorescence (LPFF) and by nylon filter packs. The detection limit was about 30 pptv for a signal accumulation time of 1 h for LPFF and about 5 pptv for the filters at a collection time of 4 h. In general, the mixing ratios of HNO3 in the Northern Hemisphere were found to be significantly higher than those in the Southern Hemisphere. The Atlantic background concentrations frequently varied between 80 pptv and the detection limit. Larger deviations from this trend were found for the more northern latitudes and for episodes like crossings of exhaust plumes from ships or from continental pollutions sources.  相似文献   

18.
硫酸盐气溶胶对全球水循环因子的影响   总被引：3，自引：0，他引：3       下载免费PDF全文
  利用卫星资料进一步检验了CAM3.0模式对云的模拟能力,该模式可以较好地再现全球云的分布和季节变化的主要特征。在硫循环过程与辐射和动力过程之间双向耦合的情况下,探讨了硫酸盐气溶胶直接气候效应对水循环过程的影响。模式较好地模拟了硫酸盐气溶胶的浓度和分布变化。硫酸盐气溶胶对水循环因子的影响在不同季节和区域是不同的,其中,北半球夏季的影响最大,这是因为北半球夏季硫酸盐浓度最高。纬向平均的云量、降水和水汽的变化形势大部分相似,存在比较密切的联系。  相似文献   

19.
Climate changes induced by human activities have attracted a great amount of attention. With this, a coupling system of an atmospheric chemistry model and a climate model is greatly needed in China for better understanding the interaction between atmospheric chemical components and the climate. As the first step to realize this coupling goal, the three-dimensional global atmospheric chemistry transport model MOZART-2 (the global Model of Ozone and Related Chemical Tracers, version 2) coupled with CAM2 (the Community Atmosphere Model, version 2) is set up and the model results are compared against observations obtained in East Asia in order to evaluate the model performance. Comparison of simulated ozone mixing ratios with ground level observations at Minamitorishima and Ryori and with ozonesonde data at Naha and Tateno in Japan shows that the observed ozone concentrations can be reproduced reasonably well at Minamitorishima but they tend to be slightly overestimated in winter and autumn while underestimated a little in summer at Ryori. The model also captures the general features of surface CO seasonal variations quite well, while it underestimates CO levels at both Minamitorishima and Ryori. The underestimation is primarily associated with the emission inventory adopted in this study. Compared with the ozonesonde data, the simulated vertical gradient and magnitude of ozone can be reasonably well simulated with a little overestimation in winter, especially in the upper troposphere. The model also generally captures the seasonal, latitudinal and altitudinal variations in ozone concentration. Analysis indicates that the underestimation of tropopause height in February contributes to the overestimation of winter ozone in the upper and middle troposphere at Tateno.  相似文献   

20.
The climate response to an increase in carbon dioxide and sea surface temperatures is examined using the Météo-France climate model. This model has a high vertical resolution in the stratosphere and predicts the evolution of the ozone mixing ratio. This quantity is fully interactive with radiation and photochemical production and loss rates are accounted for. Results from a 5-year control run indicate a reasonable agreement with observed climatologies. A 5-year simulation is performed with a doubled CO2 concentration using, as lower boundary conditions, mean surface temperatures anomalies and sea ice limits predicted for the years 56–65 of a 100-year transient simulation performed at Hamburg with a global coupled atmosphere-ocean model. The perturbed simulation produces a global mean surface air warming of 1.4 K and an increase in global mean precipitation rate of 4%. Outside the high latitudes in the Northern Hemisphere, the model simulates a strong cooling in the stratosphere reaching 10 K near the stratopause. Temperature increases are noticed in the lower polar stratosphere of the Northern Hemisphere caused by an intensification in the frequency of sudden warmings in the perturbed simulation. The low and mid-latitude stratospheric cooling leads to an ozone column enhancement of about 5%. Other features present in similar studies are exhibited in the troposphere such as the stronger surface warming over polar regions of the Northern Hemisphere, the summer time soil moisture drying in mid-latitudes and the increase in high convective cloudiness in tropical regions.This paper was presented at the Second International Conference on Modelling of Global Climate Variability, held in Hamburg 7–11 September 1992 under the auspices of the Max Planck Institute for Meteorology. Guest Editor for these papers is L. Dümenil Correspondence to: JF Mahfouf  相似文献   

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