Journal of Geophysical Research: Atmospheres最新文献_第8页

Virtual Reflection Height of Nighttime Equatorial Ionosphere Estimated With Low-Frequency Magnetic Sferics Measured in Malacca 利用在马六甲测量到的低频磁干扰估计夜间赤道电离层的虚拟反射高度

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-14 DOI: 10.1029/2023JD040099

Yongping Wang, Gaopeng Lu, Zhengwei Cheng, Ziru Niu, Yazhou Chen, Kang-Ming Peng, Seah Boon York, Mohd Riduan Ahmad

{"title":"Virtual Reflection Height of Nighttime Equatorial Ionosphere Estimated With Low-Frequency Magnetic Sferics Measured in Malacca","authors":"Yongping Wang, Gaopeng Lu, Zhengwei Cheng, Ziru Niu, Yazhou Chen, Kang-Ming Peng, Seah Boon York, Mohd Riduan Ahmad","doi":"10.1029/2023JD040099","DOIUrl":"https://doi.org/10.1029/2023JD040099","url":null,"abstract":"The return stroke of cloud-to-ground (CG) lightning is an impulsive radiator of very low-frequency/low-frequency (VLF/LF) electromagnetic signals allowing for the remote sensing of lower ionosphere over large spatial coverage. In this study, we examined the LF magnetic fields measured in Malacca, Malaysia, to probe reflection heights of the lower ionosphere near the equator on three different nights in 2021. The results show that the virtual ionospheric height at nighttime typically ranged from 82.0 to 90.0 km, with a mean value of 85.3 km. Our measurements also revealed significant variations in the virtual ionospheric height across different regions over a spatial scale of about 800 km. The maximum height difference was about 5.0 km. Moreover, the fluctuation characteristics are observed in both estimated ionospheric height and calculated peak reflection ratio during similar periods. This fluctuation may be related to atmospheric gravity waves in the nighttime ionosphere. In addition, we compared the virtual ionospheric height estimated from CG strokes of different polarities, and the results showed that the virtual reflection height for positive CG strokes is lower than that for negative ones.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JD040099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Large Eddy Simulations of the Interaction Between the Atmospheric Boundary Layer and Degrading Arctic Permafrost 大气边界层与退化的北极永久冻土之间相互作用的大涡流模拟

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-14 DOI: 10.1029/2024JD040794

M. Schlutow, T. Stacke, T. Doerffel, P. K. Smolarkiewicz, M. Göckede

{"title":"Large Eddy Simulations of the Interaction Between the Atmospheric Boundary Layer and Degrading Arctic Permafrost","authors":"M. Schlutow, T. Stacke, T. Doerffel, P. K. Smolarkiewicz, M. Göckede","doi":"10.1029/2024JD040794","DOIUrl":"https://doi.org/10.1029/2024JD040794","url":null,"abstract":"Arctic permafrost thaw holds the potential to drastically alter the Earth's surface in Northern high latitudes. We utilize high-resolution large eddy simulations to investigate the impact of the changing surfaces onto the neutrally stratified atmospheric boundary layer (ABL). A stochastic surface model based on Gaussian Random Fields modeling typical permafrost landscapes is established in terms of two land cover classes: grass land and open water bodies, which exhibit different surface roughness length and surface sensible heat flux. A set of experiments is conducted where two parameters, the lake areal fraction and the surface correlation length, are varied to study the sensitivity of the boundary layer with respect to surface heterogeneity. Our key findings from the simulations are the following: The lake areal fraction has a substantial impact on the aggregated sensible heat flux at the blending height where surface heterogeneities become horizontally homogenized. The larger the lake areal fraction, the smaller the sensible heat flux. This result gives rise to a potential feedback mechanism. When the Arctic dries due to climate heating, the interaction with the ABL may accelerate permafrost thaw. Furthermore, the blending height shows significant dependency on the correlation length of the surface features. A longer surface correlation length causes an increased blending height. This finding is of relevance for land surface models concerned with Arctic permafrost as they usually do not consider a heterogeneity metric comparable to the surface correlation length.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD040794","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing the Variability of Aerosol Optical Depth Over India in Response to Future Scenarios: Implications for Carbonaceous Aerosols 评估印度上空气溶胶光学深度随未来情景的变化情况：对碳质气溶胶的影响

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-14 DOI: 10.1029/2024JD040846

Nidhi L. Anchan, Basudev Swain, Amit Sharma, Aishwarya Singh, Chakradhar Reddy Malasani, Arundathi Chandrasekharan, Utkarsh Kumar, Narendra Ojha, Pengfei Liu, Marco Vountas, Sachin S. Gunthe

{"title":"Assessing the Variability of Aerosol Optical Depth Over India in Response to Future Scenarios: Implications for Carbonaceous Aerosols","authors":"Nidhi L. Anchan, Basudev Swain, Amit Sharma, Aishwarya Singh, Chakradhar Reddy Malasani, Arundathi Chandrasekharan, Utkarsh Kumar, Narendra Ojha, Pengfei Liu, Marco Vountas, Sachin S. Gunthe","doi":"10.1029/2024JD040846","DOIUrl":"https://doi.org/10.1029/2024JD040846","url":null,"abstract":"Air pollution caused by various anthropogenic activities and biomass burning continues to be a major problem in India. To assess the effectiveness of current air pollution mitigation measures, we used a 3D global chemical transport model to analyze the projected optical depth of carbonaceous aerosol (AOD) in India under representative concentration pathways (RCP) 4.5 and 8.5 over the period 2000–2100. Our results show a decrease in future emissions, leading to a decrease in modeled AOD under both RCPs after 2030. The RCP4.5 scenario shows a 48%–65% decrease in AOD by the end of the century, with the Indo-Gangetic Plain (IGP) experiencing a maximum change of <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>25% by 2030 compared to 2010. Conversely, RCP8.5 showed an increase in AOD of <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>29% by 2050 and did not indicate a significant decrease by the end of the century. Our study also highlights that it is likely to take three decades for current policies to be effective for regions heavily polluted by exposure to carbonaceous aerosols, such as the IGP and eastern India. We emphasize the importance of assessing the effectiveness of current policies and highlight the need for continued efforts to address the problem of air pollution from carbonaceous aerosols, both from anthropogenic sources and biomass burning, in India.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Biogenic Volatile Organic Compound Emission and Its Response to Land Cover Changes in China During 2001–2020 Using an Improved High-Precision Vegetation Data Set 利用改进的高精度植被数据集计算 2001-2020 年中国生物源挥发性有机化合物排放量及其对土地覆盖变化的响应

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-14 DOI: 10.1029/2023JD040421

Jing Cao, Huijuan Han, Lili Qiao, Lingyu Li

{"title":"Biogenic Volatile Organic Compound Emission and Its Response to Land Cover Changes in China During 2001–2020 Using an Improved High-Precision Vegetation Data Set","authors":"Jing Cao, Huijuan Han, Lili Qiao, Lingyu Li","doi":"10.1029/2023JD040421","DOIUrl":"https://doi.org/10.1029/2023JD040421","url":null,"abstract":"Biogenic volatile organic compounds (BVOCs) are regarded as important precursors for ozone and secondary organic aerosol, mainly from vegetation emissions. In the context of the expanding trend of vegetation greening, the development of high-precision vegetation data and accurate BVOC emission estimates are essential to develop effective air pollution control measures. In this study, by integrating the multi-source vegetation cover data, we established a high-resolution vegetation distribution (HRVD) data set to develop a high spatio-temporal resolution emission inventory and investigated the impact of different land cover data sets on emission simulation and impact of land cover change on BVOC emissions during 2001–2020. The annual total BVOC emissions in China for 2020 was 15.66 Tg, which were mainly from trees. The emissions simulated by CNLUCC and MODIS data sets were 1.53% and 1.72% higher than those simulated by HRVD data sets, respectively. The spatial distribution of emission differences was consistent with that of land cover differences. The simulated BVOC emissions by the HRVD data set had the best accuracy as they improved the bias between modeling and observation from 69.06% to 65.35% and decreased the underprediction of observations by a factor of 2.13 compared with simulation by MEGAN default vegetation data. The annual BVOC emissions caused by changing vegetation distribution and LAIv (LAI of vegetation covered surfaces) enhanced at a rate of 72.06 Gg yr−1 during 2001–2020. LAIv was the main driver of emission variations. The total OH reactivity of the resulted BVOC emissions increased at a rate of 1.59 s−1 yr−1, with isoprene contributed the most.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vertical Profile Climatology of Polarimetric Radar Variables and Retrieved Microphysical Parameters in Synoptic and Lake Effect Snowstorms 同步暴风雪和湖泊效应暴风雪中极坐标雷达变量的垂直剖面气候学和检索到的微物理参数

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-13 DOI: 10.1029/2024JD041318

Jiaxi Hu, Alexander Ryzhkov, Edwin L. Dunnavan

{"title":"Vertical Profile Climatology of Polarimetric Radar Variables and Retrieved Microphysical Parameters in Synoptic and Lake Effect Snowstorms","authors":"Jiaxi Hu, Alexander Ryzhkov, Edwin L. Dunnavan","doi":"10.1029/2024JD041318","DOIUrl":"https://doi.org/10.1029/2024JD041318","url":null,"abstract":"This study derives polarimetric radar vertical profiles and microphysical retrievals for 25 Synoptic Snow (SS) and 23 Lake Effect Snow (LES) cases using the Range-Defined Quasi-Vertical Profiles (RD-QVP), Columnar Vertical Profiles (CVP), and Process-oriented Vertical Profiles (POVP) methods. For all vertical profile techniques, SS cases exhibit a near-linear increase in reflectivity from −30 to 0°C whereas ZDR and Kdp locally peak in the dendritic growth layer. LES cases universally exhibit negative ZDR, rather high Z, negligible Kdp, and near-unity ρhv. Ground measurements from the past OWLeS campaign provide direct evidence that conical graupel may strongly affect these polarimetric measurements in LES bands. Aggregation efficiencies for SS cases are estimated by optimizing the theoretical number concentration (Nt) and mean volume diameter (Dm) steady-state vertical profiles against radar-retrieved profiles derived from 20 of the 25 synoptic storm RD-QVPs. The median estimated aggregation efficiency is approximately 0.15 with a relatively narrow interquartile range that spans from 0.1 to just over 0.2. Values of optimized aggregation efficiencies are nearly independent of the assumed gamma distribution shape parameter. These results are used to derive temperature-dependent, climatological steady-state relations for vertical profiles of Nt, Dm, and liquid-equivalent snowfall rates. These results can be used in numerical weather prediction model aggregation parameterizations and can also provide climatologically representative vertical profiles of radar and microphysical quantities.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142230992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impacts of Local Circulations on Ozone Pollution in the New York Metropolitan Area: Evidence From Three Summers of Observations 当地环流对纽约大都会区臭氧污染的影响：三个夏季的观测证据

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-13 DOI: 10.1029/2023JD039206

Huiying Luo, Cheng-Hsuan Lu

{"title":"Impacts of Local Circulations on Ozone Pollution in the New York Metropolitan Area: Evidence From Three Summers of Observations","authors":"Huiying Luo, Cheng-Hsuan Lu","doi":"10.1029/2023JD039206","DOIUrl":"https://doi.org/10.1029/2023JD039206","url":null,"abstract":"Elevated surface ozone levels are often detected in the New York metropolitan area during summertime. Moreover, surface ozone in this region exhibits sharp spatial gradients and distinctive diurnal cycles under the influence of complex boundary layer circulations induced by the intricate coastal geometry. This study examines how surface ozone is impacted by local circulations spatially and temporally under different temperature scenarios (all summer days, hot summer days, and extreme heat days) with the help of cluster-based meteorological conditions during the summertime of 2017–2019. The most polluted days are found to be highly associated with hot sea breeze days with weak background flow. When sea breeze development in the New York Bight is delayed and its penetration north is intercepted by the dominant westerlies during hot summer days, daily maximum 8-hr average ozone (DMA8) in some ozone hot spots of New York City (NYC) and the south shore of Connecticut (CT) typically drops 9–10 ppb under comparable temperature levels. The average regional decrease of DMA8 for NYC and coastal CT is 6.7 and 8.3 ppb, respectively. Furthermore, we conclude that a change in early morning meridional wind direction is the most critical meteorological characteristic in controlling sea breeze onset type and helping modulate ozone exceedances in the region during extreme hot days when ozone exceedances are expected to be very common. The conclusion is further demonstrated with two case studies during the Long Island Sound Tropospheric Ozone Study 2018 field campaign.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JD039206","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142230994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Geostatistics-Based Tool to Characterize Spatio-Temporal Patterns of Remotely Sensed Land Surface Temperature Fields Over the Contiguous United States 基于地质统计学的工具，用于描述美国毗连地区遥感陆地表面温度场的时空模式

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-13 DOI: 10.1029/2023JD040679

L. Torres-Rojas, T. Waterman, J. Cai, E. Zorzetto, H. M. Wainwright, N. W. Chaney

{"title":"A Geostatistics-Based Tool to Characterize Spatio-Temporal Patterns of Remotely Sensed Land Surface Temperature Fields Over the Contiguous United States","authors":"L. Torres-Rojas, T. Waterman, J. Cai, E. Zorzetto, H. M. Wainwright, N. W. Chaney","doi":"10.1029/2023JD040679","DOIUrl":"https://doi.org/10.1029/2023JD040679","url":null,"abstract":"Surface fluxes and states can recur and remain consistent across various spatial and temporal scales, forming space-time patterns. Quantifying and understanding the observed patterns is desirable, as they provide information about the dynamics of the processes involved. This study introduces the empirical spatio-temporal covariance function and a corresponding parametric covariance function as tools to identify and characterize spatio-temporal patterns in remotely sensed fields. The method is demonstrated using 2 km hourly GOES-16/17 land surface temperature (LST) data over the Contiguous United States by splitting the area into 1.0° × 1.0° domains. The summer day-time LST ESTCFs for 2018 to 2022 are derived for each domain, and a parametric covariance model is fitted. Clustering analysis is applied to detect areas with similar spatio-temporal LST patterns. Six main zones within CONUS are identified and characterized based on their variance and temporal and spatial characteristic length scales (i.e., scales for which the temperature variations are temporally and spatially related), respectively: (a) Eastern plains with 3 K2, ∼6 hr, and 0.15°, (b) Gulf of California with 60 K2, ∼8 hr, and 0.34°, (c) mountains and coasts transition 1 with 16 K2, ∼11 hr, and 0.25°, (d) central US, Midwest, and South cities with 5.5 K2, ∼8 hr, and ∼0.2°, (e) mountains and coasts transition 2 with ∼10 K2, ∼8 hr, and 0.2°, and (f) largest mountains and coastlines with ∼19 K2, ∼13 hr, and 0.3°. The tools introduced provide a pathway to formally identify and summarize the spatio-temporal patterns observed in remotely sensed fields and relate those to more complex processes within the Soil-Vegetation-Atmosphere System.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142230993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tropical Aviation Turbulence Induced by the Interaction Between a Jet Stream and Deep Convection 喷流与深对流相互作用引发的热带航空湍流

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-13 DOI: 10.1029/2024JD040763

Haoming Chen, Xiaoming Shi, Xiuwen Nie, Yueya Wang, Christy Yan Yu Leung, Ping Cheung, Pak Wai Chan

{"title":"Tropical Aviation Turbulence Induced by the Interaction Between a Jet Stream and Deep Convection","authors":"Haoming Chen, Xiaoming Shi, Xiuwen Nie, Yueya Wang, Christy Yan Yu Leung, Ping Cheung, Pak Wai Chan","doi":"10.1029/2024JD040763","DOIUrl":"https://doi.org/10.1029/2024JD040763","url":null,"abstract":"On 18 December 2022, Hawaiian Airlines flight HA35 encountered severe turbulence without warning in a cloud-free height. We reproduced this incident using the Weather Research and Forecasting Model (WRF) at a convection-permitting resolution. We found that this case of tropical upper-level turbulence occurred primarily due to the fast-growing convective tower in the unstable layer created by gravity wave breaking. At lower altitudes, a mesoscale convective system (MCS) caused a decrease in wind speed in both upstream and downstream regions. At upper levels, a large-scale jet descended and accelerated after flowing over the top of the MCS, which acted like a barrier and produced a situation similar to a downslope windstorm due to mountain terrain. Upper-level turbulence is 2–3 km higher than the top of the MCS. The critical level above the jet and the locally self-induced critical level created the locally enhanced descending jet stream, which destabilized the flow through Kelvin–Helmholtz instabilities. The convective tower existed near the flight route and played an important role in triggering turbulence in the unstable environment through its convective gravity waves.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD040763","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142230991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Understanding Terrestrial Water and Carbon Cycles and Their Interactions Using Integrated SMAP Soil Moisture and OCO-2 SIF Observations and Land Surface Models 利用 SMAP 土壤水分和 OCO-2 SIF 综合观测数据以及陆地表面模型了解陆地水循环和碳循环及其相互作用

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-12 DOI: 10.1029/2024JD041077

Zhijiong Cao, Yongkang Xue, Hara Prasad Nayak, Dennis P. Lettenmaier, Christian Frankenberg, Philipp Köhler, Ziwei Li

{"title":"Understanding Terrestrial Water and Carbon Cycles and Their Interactions Using Integrated SMAP Soil Moisture and OCO-2 SIF Observations and Land Surface Models","authors":"Zhijiong Cao, Yongkang Xue, Hara Prasad Nayak, Dennis P. Lettenmaier, Christian Frankenberg, Philipp Köhler, Ziwei Li","doi":"10.1029/2024JD041077","DOIUrl":"https://doi.org/10.1029/2024JD041077","url":null,"abstract":"Recently, more advanced synchronous global-scale satellite observations, the Soil Moisture Active Passive enhanced Level 3 (SMAP L3) soil moisture product and the Orbiting Carbon Observatory 2 (OCO-2) solar-induced chlorophyll fluorescence (SIF) product, provide an opportunity to improve the predictive understanding of both water and carbon cycles in land surface modeling. The Simplified Simple Biosphere Model version 4 (SSiB4) was coupled with the Top-down Representation of Interactive Foliage and Flora Including Dynamics Model (TRIFFID) and a mechanistic representation of SIF. Incorporating dynamic vegetation processes reduced global SIF root-mean-squared error (RMSE) by 12%. Offline experiments were conducted to understand the water and carbon cycles and their interactions using satellite data as constraints. Results indicate that soil hydraulic properties, the soil hydraulic conductivity at saturation (Ks) and the water retention curve, significantly impact soil moisture and SIF simulation, especially in the semi-arid regions. The wilting point and maximum Rubisco carboxylation rate (Vmax) affect photosynthesis and transpiration, then soil moisture. However, without atmospheric feedback processes, their effects on soil moisture are undermined due to the compensation between soil evaporation and transpiration. With optimized parameters based on SMAP L3 and OCO-2 data, the global RMSE of soil moisture and SIF simulations decreased by 15% and 12%, respectively. These findings highlight the importance of integrating advanced satellite data and dynamic vegetation processes to improve land surface models, enhancing understanding of terrestrial water and carbon cycles.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sampling Error of Mean and Trend of Nighttime Air Temperature at Weather Stations Over China Using Satellite Data as Proxy 以卫星数据为代表的中国气象站夜间气温平均值和变化趋势的采样误差

IF 3.8 2区地球科学

Journal of Geophysical Research: Atmospheres Pub Date : 2024-09-12 DOI: 10.1029/2023JD039914

Linghong Chen, Kaicun Wang

{"title":"Sampling Error of Mean and Trend of Nighttime Air Temperature at Weather Stations Over China Using Satellite Data as Proxy","authors":"Linghong Chen, Kaicun Wang","doi":"10.1029/2023JD039914","DOIUrl":"https://doi.org/10.1029/2023JD039914","url":null,"abstract":"Meteorological observations of surface air temperature have provided fundamental data for climate change detection and attribution. However, the weather stations are unevenly distributed, and are still very sparse in remote regions. The possible sampling error is well known, but not well quantified because we are lack of the adequate and regularly distributed measurements. The high resolution of satellite land surface temperature retrieval during night time provide a nice proxy for near surface temperature as both temperatures controlled by surface longwave radiative cooling and the nocturnal temperature inversion depress land-atmosphere turbulent exchange. The sampling error of mean value and trend were assessed by comparing station point measurements (pixel of ∼0.01°) with grid (1°) mean and national mean from 2001 to 2021. This method permits us to make the first assessment of under-sampling error and spatial representative error on both national mean and trend of air temperature during nighttime collected at ∼2,400 weather stations over China. The sampling error in national mean temperature is more than 3°C. The under-sampling error due to lack of observation explains two thirds and the spatial representative error due to the difference between station and grid/regional mean elevation contribute the other one third. The sampling error in trend account for one third of the national mean trend. The urban heat island effect associated with urbanization around the weather stations (spatial representative error) can explain four fifths of the sampling error in trend, which is consistent with existing studies based on air temperature collected at paired weather station.","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0