Journal of Hydrometeorology最新文献_第2页

Statistical Analysis of Moisture Sources and Quantitative Contribution of Cold Vortex Rainstorms in Northeast China During Warm Season 中国东北暖季冷涡暴雨的水汽来源和定量贡献统计分析

Journal of Hydrometeorology Pub Date : 2024-04-09 DOI: 10.1175/jhm-d-23-0226.1

Yuting Yang, Xiaopeng Cui, Ying Li, Lijun Huang, Jia Tian

{"title":"Statistical Analysis of Moisture Sources and Quantitative Contribution of Cold Vortex Rainstorms in Northeast China During Warm Season","authors":"Yuting Yang, Xiaopeng Cui, Ying Li, Lijun Huang, Jia Tian","doi":"10.1175/jhm-d-23-0226.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0226.1","url":null,"abstract":"\u0000The northeast cold vortex (NECV) is an essential system in the northeast region of China (NER). Understanding the moisture source and associated transport characteristics of NECV rainstorms is key to the knowledge of its mechanisms. In this study, we focus on two NECV rainstorm centers during the warm season (May-September) from 2008 to 2013. The FLEXPART model and quantitative contribution analysis method are applied to reveal the moisture sources and their quantitative contribution. The results demonstrate that for the northern NECV rainstorm center (R1), Northeast Asia (35.66%), east-central China and its coastal regions (29.14%) make prominent moisture contributions, followed by R1 (11.37%). Whereas east-central China and its coastal regions (45.16%), the southern NECV rainstorm center itself (R2, 17.90%) and the Northwest Pacific (10.24%) principally contribute to R2. Moisture uptake of Northeast Asia differs between R1 and R2, which could serve as one of the vital indicators to judge where NECV rainstorm falls in NER. Moisture from the Arabian Sea, the Bay of Bengal, and the South China Sea, suffers massive en-route loss, although these sources’ contribution and uptake are positively correlated with the intensity and scale of NECV rainstorms in the two centers. There exists inter-month and geographical variability in NECV rainstorms when the main moisture source region contributes the most. Regulated by the atmospheric circulation and the East Asian summer monsoon, the particle trajectories and source contributions of NECV rainstorms vary from month to month. Sources’ contribution also turns out to be diverse in the overall warm season.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140727266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Which Error Components in TRMM-Based Multisatellite Precipitation Estimates Reduce over Chinese Mainland after Official Bias Adjustments: Systematic or Random? 基于 TRMM 的多卫星降水量估算中的哪些误差成分在官方偏差调整后会在中国大陆上空减少？系统性还是随机性？

Journal of Hydrometeorology Pub Date : 2024-04-01 DOI: 10.1175/jhm-d-23-0172.1

Z. Shen, Bin Yong, Hao Wu

{"title":"Which Error Components in TRMM-Based Multisatellite Precipitation Estimates Reduce over Chinese Mainland after Official Bias Adjustments: Systematic or Random?","authors":"Z. Shen, Bin Yong, Hao Wu","doi":"10.1175/jhm-d-23-0172.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0172.1","url":null,"abstract":"\u0000Climatological calibration algorithm (CCA) and satellite–gauge combination (SG) are two official bias adjustments for satellite precipitation estimates (SPE) in the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA). The CCA is designed for the near-real-time SPEs, while the SG procedure is a final step to merge pure SPEs with gauge observations. This study explored the impacts of CCA and SG on the systematic and random errors of TMPA SPEs. The errors of TMPA version-7 near-real-time products before and after CCA (RT_UC, RT_C), and the research product TMPA 3B42 (V7), were decomposed into systematic and random components, benchmarked by the China Gauge-based Daily Precipitation Analysis (CGDPA). After being calibrated by CCA, RT_C reduced the systematic errors relative to RT_UC over the Chinese mainland, except in the Tibetan Plateau and Tianshan Mountains. However, CCA did not aid in reducing random errors; instead, it even exacerbated the random errors. On the other hand, the SG merging is more effective in reducing systematic errors of SPEs than CCA calibration because of the direct inclusion of simultaneous gauge data from the Global Precipitation Climatology Centre (GPCC). We also found that SG merging reduced the random errors of pure SPEs over regions with relatively higher elevations. Despite lower random errors in V7 over the complex terrain region, the SG unfavorably increased the random errors over southeastern China. The results reported here may offer valuable insights into the effects of CCA and SG techniques drawn from TMPA, with the potential to advance the development of bias-adjusting algorithms for SPEs in the future.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140777010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Using Median Point in Keeling Plot to Reduce the Uncertainty of the Isotopic Composition of Evapotranspiration 利用基林图中的中值点降低蒸散同位素组成的不确定性

Journal of Hydrometeorology Pub Date : 2024-04-01 DOI: 10.1175/jhm-d-23-0133.1

Yusen Yuan, Lixin Wang, Zhongwang Wei, H. Ajami, Honglang Wang, Taisheng Du

{"title":"Using Median Point in Keeling Plot to Reduce the Uncertainty of the Isotopic Composition of Evapotranspiration","authors":"Yusen Yuan, Lixin Wang, Zhongwang Wei, H. Ajami, Honglang Wang, Taisheng Du","doi":"10.1175/jhm-d-23-0133.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0133.1","url":null,"abstract":"\u0000The isotopic composition of evapotranspiration δET is a crucial parameter in isotope-based evapotranspiration (ET) partitioning and moisture recycling studies. The Keeling plot method is the most prevalent method to calculate δET, though it contains large extrapolated uncertainties from the least squares regression. Traditional Keeling regression uses the mean point of individual measurements. Here, a modified Keeling plot framework was proposed using the median point of individual measurements. We tested the δET uncertainty using the mean point [σET (mean)] and median point [σET (median)]. Multiple resolutions of input and output data from six independent sites were used to test the performance of the two methods. The σET (mean) would be greater than σET (median) when the mean value of inverse vapor concentration () is greater than the median value of inverse vapor concentration []. When applying the filter of r2 > 0.8, around 70% of σET (mean) was greater than σET (median). This phenomenon might be due to the normality of the vapor concentration Cυ producing the asymmetric distribution of 1/Cυ. The median method could perform significantly better than the mean method when inputting high-resolution measurements (e.g., 1 Hz) and when the water vapor concentration Cυ is relatively low. Compared to the mean method, applying the median method could on average reduce 6.88% of ET partitioning uncertainties and could on average reduce 9.00% of moisture recycling uncertainties. This study provided a new insight of the Keeling plot method and emphasized handling model output uncertainty from multiple perspectives instead of only from input parameters.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140797489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Artificial Trends or Real Changes? Investigating Precipitation Records in Ny-Ålesund, Svalbard 人为趋势还是真实变化？调查斯瓦尔巴群岛尼-奥勒松的降水记录

Journal of Hydrometeorology Pub Date : 2024-03-29 DOI: 10.1175/jhm-d-23-0182.1

Olivier Champagne, Olga Zolina, Jean-Pierre Dedieu, Mareile Wolff, Hans-Werner Jacobi

{"title":"Artificial Trends or Real Changes? Investigating Precipitation Records in Ny-Ålesund, Svalbard","authors":"Olivier Champagne, Olga Zolina, Jean-Pierre Dedieu, Mareile Wolff, Hans-Werner Jacobi","doi":"10.1175/jhm-d-23-0182.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0182.1","url":null,"abstract":"\u0000The Svalbard archipelago, in the Atlantic-Arctic region, has been affected by a strong increase in precipitation in the last decades, with major potential impacts for the cryosphere, bio-geochemical cycles, and the ecosystems. Ny-Ålesund (79°N), in the northwest part of Svalbard, hosts invaluable meteorological records widely used by many researchers. Among the observed parameters, the amount of precipitation is subject to large biases, mainly due to the well-known precipitation gauges undercatch during windy conditions. The purpose of this study is to investigate if the observed trend of precipitation in Ny-Ålesund in the 1975-2022 period was real and how it was impacted by the gauge undercatch. We applied several correction factors developed in the last decades, based on local wind speed and temperature. We forced these corrections with 12-hourly precipitation data from the Ny-Ålesund weather station. Taking the period 1975-2022, the trend of precipitation increased from 3.8 mm/year in the observations to 4.5 mm/year (±0.2) after the corrections, mainly due to enhanced snowfall in November to January months. Taking the most recent 40 years period (1983-2022), the amount of precipitation still increased by 3.8 mm/year in the observations, but only by 2.6 mm/year (±0.5) after the corrections. The recent observed trend of precipitation stays large due to an increase of wet snowfall and rainfall that are measured more efficiently by the precipitation gauge. This result shows the need of applying corrections factors when using precipitation gauge data, especially in regions exhibiting large inter-annual changes of weather conditions.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140366617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Subseasonal forecast skill of evaporative demand, soil moisture, and flash drought onset from two dynamic models over the contiguous United States 两个动态模型对美国毗连地区蒸发需求、土壤水分和山洪暴发干旱的次季节预报技能

Journal of Hydrometeorology Pub Date : 2024-03-29 DOI: 10.1175/jhm-d-23-0124.1

Kyle Lesinger, Di Tian, Hailan Wang

{"title":"Subseasonal forecast skill of evaporative demand, soil moisture, and flash drought onset from two dynamic models over the contiguous United States","authors":"Kyle Lesinger, Di Tian, Hailan Wang","doi":"10.1175/jhm-d-23-0124.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0124.1","url":null,"abstract":"\u0000Flash droughts are rapid developing subseasonal climate extreme events that are manifested as suddenly decreased soil moisture, driven by increased evaporative demand and/or sustained precipitation deficits. Over each climate region in the contiguous United States (CONUS), we evaluated forecast skill of weekly root-zone soil moisture (RZSM), evaporative demand (ETo), and relevant flash drought (FD) indices derived from two dynamic models (GEOSV2p1 and GEFSv12) in the Subseasonal Experiment (SubX) project between years 2000-2019 against three reference datasets: MERRA-2, NLDAS-2, and GEFSv12 reanalysis. ETo and its forcing variables at lead week 1 have moderate to high anomaly correlation coefficient (ACC) skill (~0.70-0.95) except downwelling shortwave radiation, and by weeks 3-4 predictability was low for all forcing variables (ACC <0.5). RZSM (0-100cm) for model GEFSv12 showed high skill at lead week 1 (~0.7-0.85 ACC) in the High Plains, West, Midwest, and South CONUS regions when evaluated against GEFSv12 reanalysis but lower skill against MERRA-2 and NLDAS-2 and ACC skill are still close to 0.5 for lead weeks 3-4, better than ETo forecasts. GEFSv12 analysis has not been evaluated against in situ observations and has substantial RZSM anomaly differences when compared to NLDAS-2 and our analysis identified GEFSv12 reforecast prediction limit, which can maximally achieve ACC ~0.6 for RZSM forecasts between lead weeks 3-4. Analysis of major FD events reveal that GEFSv12 reforecast inconsistently captured the correct location of atmospheric and RZSM anomalies contributing to FD onset, suggesting the needs for improving the dynamic models’ assimilation and initialization procedures to improve subseasonal FD predictability.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140367750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Classifying microwave radiometer observations over The Netherlands into dry, shallow-, and non-shallow precipitation using a random forest model 利用随机森林模型将荷兰上空的微波辐射计观测数据分为干降水、浅降水和非浅降水三类

Journal of Hydrometeorology Pub Date : 2024-03-26 DOI: 10.1175/jhm-d-23-0202.1

L. Bogerd, Chris Kidd, Christian Kummerow, H. Leijnse, A. Overeem, V. Petković, K. Whan, R. Uijlenhoet

{"title":"Classifying microwave radiometer observations over The Netherlands into dry, shallow-, and non-shallow precipitation using a random forest model","authors":"L. Bogerd, Chris Kidd, Christian Kummerow, H. Leijnse, A. Overeem, V. Petković, K. Whan, R. Uijlenhoet","doi":"10.1175/jhm-d-23-0202.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0202.1","url":null,"abstract":"\u0000Spaceborne microwave radiometers represent an important component of the Global Precipitation Measurement (GPM) mission due to their frequent sampling of rain systems. Microwave radiometers measure microwave radiation (brightness temperatures, Tb), which can be converted into precipitation estimates with appropriate assumptions. However, detecting shallow precipitation systems using space-borne radiometers is challenging, especially over land, as their weak signals are hard to differentiate from those associated with dry conditions. This study uses a random forest model (RF) to classify microwave radiometer observations as dry, shallow, or non-shallow over the Netherlands - a region with varying surface conditions and frequent occurrence of shallow precipitation. The RF is trained on five years of data (2016-2020) and tested with two independent years (2015, 2021). The observations are classified using ground-based weather radar echo top heights. Various RF models are assessed, such as using only GPM’s Microwave Imager (GMI) Tb values as input features or including spatially aligned ERA-5 2-meter temperature and freezing level reanalysis and/or Dual Precipitation Radar (DPR) observations. Independent of the input features, the model performs best in summer and worst in winter. The model classifies observations from high-frequency channels (≥85 GHz) with lower Tb-values as non-shallow, higher values as dry, and those in between as shallow. Misclassified footprints exhibit radiometric characteristics corresponding to their assigned class. Case studies reveal dry observations misclassified as shallow are associated with lower Tb-values, likely resulting from the presence of ice particles in non-precipitating clouds. Shallow footprints misclassified as dry are likely related to the absence of ice particles.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140378668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-level liquid-bearing clouds contribute to seasonal lower atmosphere stability and surface energy forcing over a high-mountain watershed environment 低层含液云有助于高山流域环境的季节性低层大气稳定性和地表能量强迫

Journal of Hydrometeorology Pub Date : 2024-03-25 DOI: 10.1175/jhm-d-23-0144.1

Joseph Sedlar, Tilden Meyers, Christopher J. Cox, Bianca Adler

{"title":"Low-level liquid-bearing clouds contribute to seasonal lower atmosphere stability and surface energy forcing over a high-mountain watershed environment","authors":"Joseph Sedlar, Tilden Meyers, Christopher J. Cox, Bianca Adler","doi":"10.1175/jhm-d-23-0144.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0144.1","url":null,"abstract":"\u0000Measurements of atmospheric structure and surface energy budgets distributed along a high-altitude mountain watershed environment near Crested Butte, Colorado, USA, from two separate, but coordinated, field campaigns, SAIL and SPLASH, are analyzed. This study identifies similarities and differences in how clouds influence the radiative budget over one snow-free summer season (2022) and two snow-covered seasons (2021-22; 2022-23) for this alpine location. A relationship between lower tropospheric stability stratification and longwave radiative flux from the presence or absence of clouds is identified. When low clouds persisted, often with signatures of supercooled liquid in winter, the lower troposphere experienced weaker stability, while radiatively clear skies that are less likely to be influenced by liquid droplets were associated with appreciably stronger lower tropospheric stratification. Corresponding surface turbulent heat fluxes partitioned differently based upon the cloud-stability stratification regime derived from early morning radiosounding profiles. Combined with the differences in the radiative budget largely resulting from dramatic seasonal differences in surface albedo, the lower atmosphere stratification, surface energy budget, and near-surface thermodynamics are shown to be modified by the effective longwave radiative forcing of clouds. The diurnal evolution of thermodynamics and surface energy components varied depending on early morning stratification state. Thus, the importance of quiescent versus synoptically-active large-scale meteorology is hypothesized as a critical forcing for cloud properties and associated surface energy budget variations. The physical relationships between clouds, radiation, and stratification can provide a useful suite of metrics for process-understanding and to evaluate numerical models in such an undersampled, highly complex terrain environment.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140381454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A retrospective hydrological uncertainty analysis using precipitation estimation ensembles for a poorly gauged basin in High Mountain Asia 利用降水估测集合对亚洲高山缺测流域进行水文不确定性回顾分析

Journal of Hydrometeorology Pub Date : 2024-03-20 DOI: 10.1175/jhm-d-23-0170.1

P. Reggiani, Oleksiy Boyko

{"title":"A retrospective hydrological uncertainty analysis using precipitation estimation ensembles for a poorly gauged basin in High Mountain Asia","authors":"P. Reggiani, Oleksiy Boyko","doi":"10.1175/jhm-d-23-0170.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0170.1","url":null,"abstract":"\u0000We study the impact of uncertain precipitation estimates on simulated streamflows for the poorly gauged Yarlung Tsangpo basin (YTB), High Mountain Asia (HMA). A process-based hydrological model at 0.5 km resolution is driven by an ensemble of precipitation estimation products (PEPs), including analyzed ground observations, high-resolution precipitation estimates, climate data records and reanalyses over the 2008-2015 control period. The model is then forced retrospectively from 1983 onward to obtain seamless discharge estimates till 2007, a period for which there is very sparse flow data coverage. Whereas temperature forcing is considered deterministic, precipitation is sampled from the predictive distribution, which is obtained through processing PEPs by means of a probabilisitc processor of uncertainty. The employed Bayesian processor combines the PEPs and outputs the predictive densities of daily precipitation depth accumulation as well as the probability of precipitation occurrence, from which random precipitation fields for probabilistic model forcing are sampled. The predictive density of precipitation is conditional on the precipitation estimation predictors that are bias-corrected and variance adjusted. For the selected HMA study site, discharges simulated from reanalysis and climate data records score lowest against observations at three flow gauging points, whereas high-resolution satellite estimates perform better, but are still outperformed by precipitation fields obtained from analyzed observed precipitation and merged products, which were corrected against ground observations. The applied methodology indicates how missing flows for poorly gauged sites can be retrieved and is further extendable to hydrological projections of climate.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140225920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Life Cycle of Precipitating Cloud Systems from Synergistic Satellite Observations: Evolution of Macrophysical Properties and Precipitation Statistics from Geostationary Cloud tracking and GPM Active and Passive Microwave Measurements 从协同卫星观测中了解降水云系的生命周期：地球静止云跟踪和 GPM 主动与被动微波测量的宏观物理特性和降水统计的演变

Journal of Hydrometeorology Pub Date : 2024-03-15 DOI: 10.1175/jhm-d-23-0185.1

C. Guilloteau, E. Foufoula‐Georgiou

{"title":"Life Cycle of Precipitating Cloud Systems from Synergistic Satellite Observations: Evolution of Macrophysical Properties and Precipitation Statistics from Geostationary Cloud tracking and GPM Active and Passive Microwave Measurements","authors":"C. Guilloteau, E. Foufoula‐Georgiou","doi":"10.1175/jhm-d-23-0185.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0185.1","url":null,"abstract":"\u0000Observations of clouds and precipitation in the microwave domain from the active radar (DPR) and the passive imager (GMI) onboard the GPM Core Observatory satellite are used in synergy with cloud tracking information derived from infrared imagery from the GOES-13 and Meteosat-7 geostationary satellites for analysis of the life cycle of precipitating cloud systems, in terms of temporal evolution of their macro-physical characteristics, in several oceanic and continental regions of the Tropics. The life cycle of each one of the several hundred thousand cloud systems tracked during the two-year (2015-2016) analysis period is divided into five equal-duration stages between initiation and dissipation. The average cloud size, precipitation intensity, precipitation top height, and convective and stratiform precipitating fractions are documented at each stage of the life cycle for different cloud categories (based upon lifetime duration). The average life cycle dynamics is found remarkably homogeneous across the different regions and is consistent with previous studies: systems peak in size around mid-life; precipitation intensity and convective fraction tend to decrease continuously from the initiation stage to the dissipation. Over the three continental regions, Amazonia, Central Africa and Sahel, at the early stages of clouds‘ life cycle, precipitation estimates from the passive GMI instrument are systematically found to be 15 to 40% lower than active radar estimates. By highlighting stage-dependent biases in state-of-the-art passive microwave precipitation estimates over land we demonstrate the potential usefulness of cloud tracking information for improving retrievals, and suggest new directions for the synergistic use of geostationary and low-Earth-orbit satellite observations.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140240253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nowcasting of high-intensity rainfall for urban applications in the Netherlands 为荷兰城市应用进行高强度降雨预报

Journal of Hydrometeorology Pub Date : 2024-03-12 DOI: 10.1175/jhm-d-23-0194.1

Guo-Shiuan Lin, R. Imhoff, Marc Schleiss, R. Uijlenhoet

{"title":"Nowcasting of high-intensity rainfall for urban applications in the Netherlands","authors":"Guo-Shiuan Lin, R. Imhoff, Marc Schleiss, R. Uijlenhoet","doi":"10.1175/jhm-d-23-0194.1","DOIUrl":"https://doi.org/10.1175/jhm-d-23-0194.1","url":null,"abstract":"\u0000Radar rainfall nowcasting has mostly been applied to relatively large (often rural) domains (e.g., river basins), although rainfall nowcasting in small urban areas is expected to be more challenging. Here, we selected 80 events with high rainfall intensities (at least one 1-km2 grid cell experiences precipitation > 15 mm h−1 for 1-h events or 30 mm d−1 for 24-h events) in five urban areas (Maastricht, Eindhoven, The Hague, Amsterdam, and Groningen) in the Netherlands. We evaluated the performance of 9,060 probabilistic nowcasts with 20 ensemble members by applying the short-term ensemble prediction system (STEPS) from Pysteps to every 10-min issue time for the selected events. We found that nowcast errors increased with decreasing (urban) areas especially when below 100 km2. In addition, at 30-min lead time, the underestimation of nowcasts was 38% larger and the discrimination ability was 11% lower for 1-h events than for 24-h events. A set of gridded correction factors for the Netherlands, CARROTS (Climatology-based Adjustments for Radar Rainfall in an Operational Setting) could adjust the bias in real-time QPE and nowcasts by 70%. Yet, nowcasts were still found to underestimate rainfall more than 50% above 40-min lead time compared to the reference, which indicates that this error originates from the nowcasting model itself. Also, CARROTS did not adjust the rainfall spatial distribution in urban areas much. In summary, radar-based nowcasting for urban areas (between 67 and 213 km2) in the Netherlands exhibits a short skillful lead time of about 20 minutes, which can only be used for last-minute warning and preparation.","PeriodicalId":503314,"journal":{"name":"Journal of Hydrometeorology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140248526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0