中国沿海风能年际变化的区域性特征成因及其预测

基于ERA5的逐小时100m风场数据,利用时间序列K-means聚类方法,将中国沿海冬季风能年际变化划分为四个区域,分别为北中国海(NorthChina Sea,NCS)、东海(East China Sea,ECS)、南海北部(Northern South China Sea,NSCS)及南海南部(SouthernSouthChinaSea,SSCS)。四个区域风能的年际变化受不同气候模态的影响,其中NCS风能的年际变化与北极涛动(ArcticOscillation,AO)有关;ECS风能的年际变化与中部型ENSO及西伯利亚高压有关;SSCS和NSCS的年际变化则和东部型ENSO及大陆高压的南北位置存在联系。鉴于影响各区域风能年际变化的气候模态具有较高的可预测性,进一步评估了多个气候模式对中国沿海风能年际变化的预测技巧。结果表明,气候模式对南中国海的风能年际变化预测技巧更高,这与气候模式对ENSO的高预测技巧有关。气候模式对北方海域风能年际变化的预测技巧较差,这和气候模式不能较好地预测AO和西伯利亚高压有关。

谷物和油料中甲酸乙酯和硫化羰本底水平评估

甲酸乙酯和硫化羰是潜在的储藏物熏蒸剂,广泛存在于大气、植物和土壤中。它们在新收获的谷物和储存的小麦、大麦、燕麦和油菜籽中的本底含量因商品、温度、含水量和储存期而异,其中甲酸乙酯含量为0.5~2.0 mg/kg,硫化羰含量为0.02~1.0 mg/kg。两种成分含量在储存后的前4~5个月呈上升趋势,然后下降,在温度高于20℃,谷物和油菜籽含水量分别大于9.5%和5%时变化最明显。这些本底含量研究对开发甲酸乙酯和硫化羰作为储藏物熏蒸剂时制定最大残留限量(MRL)和市场接受度值有重要参考价值。

Downscaling Seasonal Precipitation Forecasts over East Africa with Deep Convolutional Neural Networks

This study assesses the suitability of convolutional neural networks(CNNs) for downscaling precipitation over East Africa in the context of seasonal forecasting. To achieve this, we design a set of experiments that compare different CNN configurations and deployed the best-performing architecture to downscale one-month lead seasonal forecasts of June–July–August–September(JJAS) precipitation from the Nanjing University of Information Science and Technology Climate Forecast System version 1.0(NUIST-CFS1.0) for 1982–2020. We also perform hyper-parameter optimization and introduce predictors over a larger area to include information about the main large-scale circulations that drive precipitation over the East Africa region, which improves the downscaling results. Finally, we validate the raw model and downscaled forecasts in terms of both deterministic and probabilistic verification metrics, as well as their ability to reproduce the observed precipitation extreme and spell indicator indices. The results show that the CNN-based downscaling consistently improves the raw model forecasts, with lower bias and more accurate representations of the observed mean and extreme precipitation spatial patterns. Besides, CNN-based downscaling yields a much more accurate forecast of extreme and spell indicators and reduces the significant relative biases exhibited by the raw model predictions. Moreover, our results show that CNN-based downscaling yields better skill scores than the raw model forecasts over most portions of East Africa. The results demonstrate the potential usefulness of CNN in downscaling seasonal precipitation predictions over East Africa,particularly in providing improved forecast products which are essential for end users.

基于改进版NUIST CFS1.1的热带大气季节内信号及其对中国气温降水影响的预测评估

基于南京信息工程大学次季节气候预测系统(NUIST CFS1.1),通过调整成员的大气初始化方案并优化了集合预测方案,构建了性能更优、计算成本更低的9成员NUIST CFS1.1 Pro系统。进一步基于实时多变量Madden-Julian Oscillation(MJO)指数和两类北半球夏季季节内振荡(Boreal Summer Intraseasonal Oscillation,BSISO)指数BSISO1和BSISO2,评估了该预测系统对热带不同季节的大气季节内振荡(ISO)的预测技巧。结果表明,NUIST CFS1.1 Pro能分别提前26、17、12 d有效预测(距平相关高于0.5)MJO、BSISO1、BSISO2,对强事件(振幅>1)的有效预测时长能分别延长到30、21、13 d。此预测性能对比国内其他最新次季节动力模式如BCC_CSM2和FGOALS-f2有一定优势,同时在与国际S2S计划的8个主要业务预测系统的技巧对比中,NUIST CFS1.1 Pro在冬季MJO和夏季BSISO1预测上处于较为领先的水平,BSISO2的预测则处于中等水平;对不同位相的计算技巧显示,冬季MJO和夏季BSISO1的2、3、6、7位相较其他位相技巧更高。进一步的分析表明,NUIST CFS1.1 Pro能提前5候准确把握冬季MJO的东传特征,并能在一定程度上预测出其对我国气温异常的影响,尤其是对位相2、3时候的冷异常预测;而在夏季,则能提前4候正确预测BSISO1的北传、西北传特征,尤其能较好地预测西北太平洋上的对流和低层环流异常,从而成功预测出BSISO1造成的我国东部地区降水异常的空间形态。然而预测的强度较观测偏弱,这需要进一步的工作来改进。

非典型大西洋尼诺对中国东部前、后汛期降水的影响

采用1979—2020年共42 a的降水观测和再分析资料,使用多变量EOF、傅立叶滤波、线性回归、T-N波通量等方法,研究了非典型大西洋尼诺(Non-Canonical Atlantic Ni1o,NCA)对中国东部夏季前、后汛期降水的影响及物理机制。结果显示,NCA在前汛期引起中国南方降水增加,但在后汛期导致华南沿海地区降水减少而北方降水增加。这是由于在前汛期,NCA的暖海温异常位于热带北大西洋,可通过“风-蒸发-海表温度”正反馈引起拉尼娜,进而激发西北太平洋异常反气旋,其西北侧的异常西南气流有助于将暖湿水汽输送至我国南方,导致前汛期南方降水增加。在后汛期,NCA的暖海温异常南移至赤道大西洋,通过调节沃克环流增强拉尼娜,使得西北太平洋异常反气旋进一步增强并覆盖华南地区,导致华南降水减少而北方降水增加。此外,与NCA相关的东传罗斯贝波列在前/后汛期位于副热带/中高纬地区,其在我国东部引起的环流异常也有助于NCA在前/后汛期影响我国南/北方降水。

Fertilization and Soil Ploughing Practices under Changing Physical Environment Lead to Soil Organic Carbon Dynamics under Conservation Agriculture in Rice-Wheat Cropping System: A Scoping Review

Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the loss of soil-organic-carbon (SOC), which further enhances soil fertility. Different fractions of SOC pools react to the alterations in management practices and indicate changes in SOC dynamics as compared to total C in the soil. Higher SOC levels in soil have been observed in case of reduced/no-till (NT) practices than conventional tillage (CT). However, between CT and zero tillage/NT, total SOC stocks diminished with an increase in soil depth, which demonstrated that the benefits of SOC are more pronounced in the topsoil under NT. Soil aggregation provides physical protection to C associated with different-sized particles, thus, the improvement in soil aggregation through CA is an effective way to mitigate soil C loss. Along with less soil disturbance, residual management, suitable crop rotation, rational application of manures and fertilizers, and integrated nutrient management have been found to be effective in not only improving soil C stock but also enhancing the soil health and productivity. Thus, CA can be considered as a potential method in the build-up of SOC of soil in rice-wheat system.

Measuring the agricultural sustainability of India:An application of Pressure-State-Response(PSR)model

Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different factors.This study provides a new suite of quantitative indicators for assessing agricultural sustainability at regional and district levels,involving environmental sustainability,social security,and economic security.Combining the PressureState-Response(PSR)model and indicator approach,this study creates a composite agricultural sustainability index for the 14 mainstream agro-climatic regions of India.The results of this study show that the Trans-Gengatic Plain Region(TGPR)ranks first in agricultural sustainability among India's 14 mainstream agro-climatic regions,while the Eastern Himalayan Region(EHR)ranks last.Higher livestock ownership,cropping intensity,per capita income,irrigation intensity,share of institutional credit,food grain productivity,crop diversification,awareness of minimum support price,knowledge sharing with fellow farmers,and young and working population,as well as better transportation facilities and membership of agricultural credit societies are influencing indicators responsible for higher agricultural sustainability in TGPR compared with EHR.Although,the scores of environmental sustainability indicators of EHR are quite good,its scores of social and economic security indicators are fairly low,putting it at the bottom of the rank of agricultural sustainability index among the 14 mainstream agroclimatic regions in India.This demonstrates the need of understanding agricultural sustainability in relation to social and economic dimensions.In a nation as diverse and complicated as India,it is the social structure that determines the health of the economy and environment.Last but not least,the sustainability assessment methodology may be used in a variety of India's agro-climatic regions.

Wave forecast in the Atlantic Ocean using a double-stage ConvLSTM network

海浪预报对海上运输安全至关重要.本研究提出了一种涵盖物理信息的深度学习模型Double-stage ConvLSTM(D-ConvLSTM)以改进大西洋的海浪预报.将D-ConvLSTM模型与海浪持续性预测和原始ConvLSTM模型的预测技巧进行对比.结果表明,预测误差随着预测时长的增加而增加.D-ConvLSTM模型在预测准确度方面优于前二者,且第三天预测的均方根误差低于0.4 m,距平相关系数约在0.8.此外,当使用IFS预测风替代再分析风时,能够产生相似的预测效果.这表明D-ConvLSTM模型的预测能力能够与ECMWF-WAM模式相当,且更节省计算资源和时间.

Solvent engineering towards scalable fabrication of high-quality perovskite films for efficient solar modules

Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,the upscaling of small-area PSCs to large-area solar modules to meet the demands of practical applications remains a significant challenge.The scalable production of high-quality perovskite films by a simple,reproducible process is crucial for resolving this issue.Furthermore,the crystallization behavior in the solution-processed fabrication of perovskite films can be strongly influenced by the physicochemical properties of the precursor inks,which are significantly affected by the employed solvents and their interactions with the solutes.Thus,a comprehensive understanding of solvent engineering for fabricating perovskite films over large areas is urgently required.In this paper,we first analyze the role of solvents in the solution-processed fabrication of large-area perovskite films based on the classical crystal nucleation and growth mechanism.Recent efforts in solvent engineering to improve the quality of perovskite films for solar modules are discussed.Finally,the basic principles and future challenges of solvent system design for scalable fabrication of high-quality perovskite films for efficient solar modules are proposed.

Impact of Forestry Interventions on Groundwater Recharge and Sediment Control in the Ganga River Basin

Water related services of natural infrastructure will help to combat the risk of water crisis, and nature-based solutions involve the management of ecosystems to mimic or optimize the natural processes for the provision and regulation of water. Forested areas provide environmental stability and supply a high proportion of the world’s accessible freshwater for domestic, agricultural, industrial and ecological needs. The present work on “Forestry Interventions for Ganga” to rejuvenate the river is one of the steps toward the Ganga River rejuvenation programme in the country. The consequences of forestry interventions for Ganga will be determined on the basis of water quantity and water quality in the Ganga River. The study conservatively estimated the water savings and sedimentation reduction of the riverscape management in the Ganga basin using the Soil Conservation Service Curve Number (SCS-CN) & GEC, 2015 and Trimble, 1999 & CWC, 2019 methodologies, respectively. Forestry plantations and soil and moisture conservation measures devised in the programme to rejuvenate the Ganga River are expected to increase water recharge and decrease sedimentation load by 231.011 MCM·yr-1 and 1119.6 cubic m·yr-1 or 395.20 tons·yr-1, respectively, in delineated riverscape area of 83,946 km2 in Ganga basin due to these interventions. The role of trees and forests in improving hydrologic cycles, soil infiltration and ground water recharge in Ganga basin seems to be the reason for this change. Forest plantations and other bioengineering techniques can help to keep rivers perennial, increase precipitation, prevent soil erosion and mitigate floods, drought & climate change. The bioengineering techniques could be a feasible tool to enhance rivers’ self-purification as well as to make river perennial. The results will give momentum to the National Mission of Clean Ganga (NMCG) and its Namami Gange programme including other important rivers in the country and provide inputs in understanding the linkages among forest structure, function, and streamflow.

Functional Genes in Relation to Residual Feed Intake in Murrah Buffalo Heifers

High Feed efficiency (FE) in growing heifers has economic importance in dairy, but remains less understood in buffaloes. Feed conversion efficiency is defined as dry matter intake (DMI) per unit body weight gain and is determined as residual feed intake (RFI), i.e., the difference between actual and predicted feed intake to gain unit body weight during a feed trial run for 78 days under control feeding. A large variation was identified ranging between -0.42 to 0.35 in growing buffalo heifers (n = 40) of age between 11 to 15 months. An average daily weight gain (ADG) varied between 382.0 and 807.6 g/day when compared with the control-fed heifers at an organized buffalo farm. The whole blood transcriptome data obtained from the selected growing heifers from extremes of estimated high and low RFI efficiency were compared with the reference assembly generated from the transcriptome of multiparous buffaloes (n = 16) of diverse age of maturity, period of regaining post partum cyclicity and level of milk production. Differentially expressed genes (DEGs) were identified using the reference genome of Mediterranean water buffalo. GO: terms (Padj 0.05, FDR 0.05) enriched by annotated DEGs and biological pathways in gene network for RFI efficiency trait were identified. GO: terms specific to pre-transcriptional regulation of nucleus and Chromatin organization under Nucleoplasm, Energy balancing, Immunity, Cell signaling, ROS optimization, ATP generation through the Electron Transport chain and cell proliferation were determined. The study reveals the indicators targeting the actual metabolic changes and molecular functions underlying the feed utilization capacity of buffaloes. Estimated RFI efficiency revealed a large variation over heifers which may lower the DMI even up to 13.6% thus, enabling an increase in ADG up to 16% by involving efficient heifers in breeding plan. The study revealed a scope of high gain by selective breeding for FE in heifers. FE variants catalogued in the study are useful breed-specific RFI markers for future reference. The study contributes to the understanding of feed efficiency in buffaloes and its association with key interactive traits such as reproduction and growth. This knowledge can be utilized to develop more effective breeding programs.

Seasonal Forecasts of Precipitation during the First Rainy Season in South China Based on NUIST-CFS1.0

Current dynamical models experience great difficulties providing reliable seasonal forecasts of regional/local rainfall in South China.This study evaluates seasonal forecast skill for precipitation in the first rainy season(FRS,i.e.,April–June)over South China from 1982 to 2020 based on the global real-time Climate Forecast System of Nanjing University of Information Science and Technology(NUIST-CFS1.0,previously known as SINTEX-F).The potential predictability and the practical forecast skill of NUIST-CFS1.0 for FRS precipitation remain low in general.But NUIST-CFS1.0 still performs better than the average of nine international models in terms of correlation coefficient skill in predicting the interannual precipitation anomaly and its related circulation index.NUIST-CFS1.0 captures the anomalous Philippines anticyclone,which transports moisture and heat northward to South China,favoring more precipitation in South China during the FRS.By examining the correlations between sea surface temperature(SST)and FRS precipitation and the Philippines anticyclone,we find that the model reasonably captures SST-associated precipitation and circulation anomalies,which partly explains the predictability of FRS precipitation.A dynamical downscaling model with 30-km resolution forced by the large-scale circulations of the NUIST-CFS1.0 predictions could improve forecasts of the climatological states and extreme precipitation events.Our results also reveal interesting interdecadal changes in the predictive skill for FRS precipitation in South China based on the NUIST-CFS1.0 hindcasts.These results help improve the understanding and forecasts for FRS precipitation in South China.

Underestimated relationship between westerly wind bursts and ENSO in CMIP6 models

观测表明,热带太平洋的西风爆发(WWBs)在厄尔尼诺南方涛动(ENSO)的发生,发展和多样性中起着关键作用.因此,在耦合模式中真实地再现WWBs对于改进ENSO的模拟和预测有重要意义.在本研究中,作者发现CMIP6的耦合模式的集合平均能很好地再现了热带太平洋WWB发生频率的纬向分布及其年际变动.然而,大多数CMIP6模型极大低估了WWB和ENSO的线性关系.这可能是因为大多数CMIP6模式里海气耦合强度低于观测:海气耦合强度与WWB-ENSO关系的模式间相关系数高达0.91.

In-Silico Identification and Differential Analysis of Mitochondrial RNA Editing Events in Helianthus Genotypes/Species and Powdery Mildew Infected Variants

Sunflower is one of the most used commercial oilseed crops and suffers due to Powdery mildew. RNA sequence alteration occurs due to RNA editing which is a post transcriptional modification. It causes a deviation from the genomic DNA sequence resulting in RNA-DNA differences. Accurate study of RNA editing events in diverse species is possible by NGS based methods. Here, we performed RNA sequencing of 12 leaf transcriptomes, which include three genotypes of Helianthus annuus (2023B, TX16R and ID25), H. debilis, H. niveus, and H. praecox along with their respective powdery mildew pathogen infected variants and systematically analysed the mitochondrial RNA editing events using computational reference-based mapping approach. We discovered 687 editing sites, 220 editing events in the protein-coding regions, among all species and genotypes considered in this study. These included “C to U” and “U to C” RNA editing events. On further analysis, we observed that these editing events include 14 different types of amino acid changes that involve the creation of two stop codon events. The conserved editing sites identified were 247 accounting for ~36% of all the editing sites identified. This study provides a detailed picture of the Helianthus species’ mitochondrial RNA editing status. We have identified and characterized for the first time, genotype-specific, species-specific, and stress-specific RNA editing events which may be useful as a potential source for stress-responsive studies in the future.

Recombinase Polymerase Amplification Based Rapid Detection of Aroma Gene in Rice

Recombinase polymerase amplification(RPA) has been emerged as an alternative to PCR due to its high specificity and sensitivity in diagnostics of animal and plant pathogens. In this study, an RPA protocol was developed and validated for detection of aroma gene in rice.

Prediction of Seasonal Tropical Cyclone Activity in the NUIST-CFS1.0 Forecast System

Prediction skill for the seasonal tropical cyclone(TC)activity in the Northern Hemisphere is investigated using the coupled climate forecast system(version 1.0)of Nanjing University of Information Science and Technology(NUISTCFS1.0).This assessment is based on the seven-month(May to November)hindcasts consisting of nine ensemble members during 1982–2019.The predictions are compared with the Japanese 55-year Reanalysis and observed tropical storms in the Northern Hemisphere.The results show that the overall distributions of the TC genesis and track densities in model hindcasts agree well with the observations,although the seasonal mean TC frequency and accumulated cyclone energy(ACE)are underestimated in all basins due to the low resolution(T106)of the atmospheric component in the model.NUIST-CFS1.0 closely predicts the interannual variations of TC frequency and ACE in the North Atlantic(NA)and eastern North Pacific(ENP),which have a good relationship with indexes based on the sea surface temperature.In the western North Pacific(WNP),NUIST-CFS1.0 can closely capture ACE,which is significantly correlated with the El Ni?o–Southern Oscillation(ENSO),while it has difficulty forecasting the interannual variation of TC frequency in this area.When the WNP is further divided into eastern and western subregions,the model displays improved TC activity forecasting ability.Additionally,it is found that biases in predicted TC genesis locations lead to inaccurately represented TC–environment relationships,which may affect the capability of the model in reproducing the interannual variations of TC activity.

Prediction of ENSO using multivariable deep learning

本文基于残差神经网络和观测数据构建了一套深度学习多因子预报测模型,以改进厄尔尼诺-南方涛动(ENSO)的预报.该模型基于最大信息系数进行因子时空特征提取,并根据泰勒图的评估标准可自动确定关键预报因子进行预报.该模型在超前8个月以内的预报性能要优于当前传统的业务预报模式.2011–2018年间,该模型的预报性能优于多模式集成预报的结果.在超前6个月预报时效上,模型预报相关性可达0.82,标准化后的均方根误差仅为0.58°C,多模式集成预报的相关性和标准化后的均方根误差分别为0.70和0.73°C.该模型春季预报障碍问题有所缓解,并且自动选取的关键预报因子可用于解释热带和副热带热动力过程对于ENSO变化的影响.

Controlled drainage in the Nile River delta of Egypt:a promising approach for decreasing drainage off-site effects and enhancing yield and water use efficiency of wheat

North Africa is one of the most regions impacted by water shortage.The implementation of controlled drainage(CD)in the northern Nile River delta of Egypt is one strategy to decrease irrigation,thus alleviating the negative impact of water shortage.This study investigated the impacts of CD at different levels on drainage outflow,water table level,nitrate loss,grain yield,and water use efficiency(WUE)of various wheat cultivars.Two levels of CD,i.e.,0.4 m below the soil surface(CD-0.4)and 0.8 m below the soil surface(CD-0.8),were compared with subsurface free drainage(SFD)at 1.2 m below the soil surface(SFD-1.2).Under each drainage treatment,four wheat cultivars were grown for two growing seasons(November 2018–April 2019 and November 2019–April 2020).Compared with SFD-1.2,CD-0.4 and CD-0.8 decreased irrigation water by 42.0%and 19.9%,drainage outflow by 40.3%and 27.3%,and nitrate loss by 35.3%and 20.8%,respectively.Under CD treatments,plants absorbed a significant portion of their evapotranspiration from shallow groundwater(22.0%and 8.0%for CD-0.4 and CD-0.8,respectively).All wheat cultivars positively responded to CD treatments,and the highest grain yield and straw yield were obtained under CD-0.4 treatment.Using the initial soil salinity as a reference,the soil salinity under CD-0.4 treatment increased two-fold by the end of the second growing season without negative impacts on wheat yield.Modifying the drainage system by raising the outlet elevation and considering shallow groundwater contribution to crop evapotranspiration promoted water-saving and WUE.Different responses could be obtained based on the different plant tolerance to salinity and water stress,crop characteristics,and growth stage.Site-specific soil salinity management practices will be required to avoid soil salinization due to the adoption of long-term shallow groundwater in Egypt and other similar agroecosystems.

Erratum to: An Isentropic Mass Circulation View on the ExtremeCold Events in the 2020/21Winter

Erratum to:Yu,Y.Y.,Y.F.Li,R.C.Ren,M.Cai,Z.Y.Guan,and W.Huang,2021:An isentropic mass circulation view on the extreme cold events in 2020/21 Winter.Adv.Atmos.Sci.,38(6),957−965,https://doi.org/10.1007/s00376-021-1289-2.

不同类型冷却屋顶方案对城市群热环境的缓解效果

利用耦合单层城市冠层模型的中尺度数值模式WRF/UCM,选取8组不同反照率和绿化比例的屋顶冷却方案进行敏感性试验,模拟研究不同冷却屋顶方案对长三角城市群2013年夏季城市热环境的影响,并分析其影响机制。结果表明:不同冷却屋顶方案对城市群热环境的缓解效果与屋顶参数之间呈很强的线性关系。高温热浪天气下,HR4(反照率为1.0)和GR4(屋顶绿化率为100%)方案的制冷度日数分别降低了14.7%和10.9%,节约的能源比普通夏日更多。同时,高温热浪天气会增强热岛强度,高反照率屋顶方案在白天对热岛起到更有效的缓解,热浪天气下日平均热岛强度最大可降低1.36℃。相同方案下,在高温热浪天气下的缓解效果均胜于普通夏日,平均而言,高反照率屋顶和屋顶绿化的降温效果分别增大38.5%和34.9%,增湿效果分别增大29.5%和21.9%,这主要是由于在高温热浪天气下,高反照率屋顶方案能够减少更多的净辐射通量,屋顶绿化方案能够释放更多的潜热通量。此外,城市格点密集区域的降温效果优于分散的城市区域,处于城市群中的常州区域较单独的杭州区域的降温幅度平均高32%。