Journal of Applied Meteorology and Climatology最新文献

On the efficacy of Monin-Obukhov and bulk Richardson surface-layer parameterizations over drylands 旱地上Monin-Obukhov和bulk Richardson表层参数化的有效性

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-08 DOI: 10.1175/jamc-d-23-0092.1

Temple R. Lee, Sandip Pal, Praveena Krishnan, Brian Hirth, M. Heuer, Tilden P. Meyers, Rick D. Saylor, John Schroeder

{"title":"On the efficacy of Monin-Obukhov and bulk Richardson surface-layer parameterizations over drylands","authors":"Temple R. Lee, Sandip Pal, Praveena Krishnan, Brian Hirth, M. Heuer, Tilden P. Meyers, Rick D. Saylor, John Schroeder","doi":"10.1175/jamc-d-23-0092.1","DOIUrl":"https://doi.org/10.1175/jamc-d-23-0092.1","url":null,"abstract":"\u0000Surface-layer parameterizations for heat, mass, momentum, and turbulence exchange are a critical component of the land surface models (LSMs) used in weather prediction and climate models. Although formulations derived from Monin-Obukhov Similarity Theory (MOST) have long been used, bulk Richardson (Rib) parameterizations have recently been suggested as a MOST alternative but have been evaluated over a limited number of land cover and climate types. Examining the parameterizations’ applicability over other regions, particularly drylands that cover approximately 41% of terrestrial land surfaces, is a critical step toward implementing the parameterizations into LSMs. One year (1 January through 31 December 2018) of eddy covariance measurements from a 10-m tower in southeastern Arizona and a 200-m tower in western Texas were used to determine how well the Rib parameterizations for friction velocity (u*), sensible heat flux (H), and turbulent kinetic energy (TKE) compare against MOST-derived parameterizations of these quantities. Independent of stability, wind speed regime, and season, the Rib u* and TKE parameterizations performed better than the MOST parameterizations, whereas MOST better represented H. Observations from the 200-m tower indicated that the parameterizations’ performance degraded as a function of height above ground. Overall, the Rib parameterizations revealed promising results, confirming better performance than traditional MOST relationships for kinematic (i.e., u*) and turbulence (i.e., TKE) quantities, although caution is needed when applying the H Rib parameterizations to drylands. These findings represent an important milestone for the use of Rib parameterizations, given the large fraction of Earth’s surface covered by drylands.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41761858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Comparison of Radar-Observed Tornadic and Nontornadic MCS Cells using Probability Matched Means 利用概率匹配方法比较雷达观测到的龙卷风和非龙卷风MCS单元

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-08 DOI: 10.1175/jamc-d-23-0070.1

Amanda M. Murphy, C. Homeyer

{"title":"Comparison of Radar-Observed Tornadic and Nontornadic MCS Cells using Probability Matched Means","authors":"Amanda M. Murphy, C. Homeyer","doi":"10.1175/jamc-d-23-0070.1","DOIUrl":"https://doi.org/10.1175/jamc-d-23-0070.1","url":null,"abstract":"\u0000Forecasting tornadogenesis remains a difficult problem in meteorology, especially for short-lived, predominantly non-supercellular tornadic storms embedded within mesoscale convective systems (MCSs). This study compares populations of tornadic non-supercellular MCS storm cells to their nontornadic counterparts, focusing on nontornadic storms that have similar radar characteristics to tornadic storms. Comparison of single-polarization radar variables during storm lifetimes show that median values of low-level, mid-level, and column-maximum azimuthal shear, as well as low-level radial divergence, enable the highest degree of separation between tornadic and nontornadic storms. Focusing on low-level azimuthal shear values, null storms were randomly selected such that the distribution of null low-level azimuthal shear values matches the distribution of tornadic values. After isolating the null cases from the nontornadic population, signatures emerge in single-polarization data that enable discrimination between nontornadic and tornadic storms. In comparison, dual-polarization variables show little deviation between storm types. Tornadic storms both at tornadogenesis and at 20-minute lead time show collocation of the primary storm updraft with enhanced near-surface rotation and convergence, facilitating the non-mesocyclonic tornadogenesis processes.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47743857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Modelled multidecadal trends of lightning and (very) large hail in Europe and North America (1950–2021) 欧洲和北美数十年来闪电和（非常）大冰雹的模拟趋势（1950–2021）

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-06 DOI: 10.1175/jamc-d-22-0195.1

Francesco Battaglioli, Pieter Groenemeijer, T. Púčik, Mateusz Taszarek, Uwe Ulbrich, Henning Rust

{"title":"Modelled multidecadal trends of lightning and (very) large hail in Europe and North America (1950–2021)","authors":"Francesco Battaglioli, Pieter Groenemeijer, T. Púčik, Mateusz Taszarek, Uwe Ulbrich, Henning Rust","doi":"10.1175/jamc-d-22-0195.1","DOIUrl":"https://doi.org/10.1175/jamc-d-22-0195.1","url":null,"abstract":"\u0000We have developed additive logistic models for the occurrence of lightning, large (≥ 2 cm), and very large (≥ 5 cm) hail to investigate the evolution of these hazards in the past, in the future, and for forecasting applications. The models, trained with lightning observations, hail reports, and predictors from atmospheric reanalysis, assign an hourly probability to any location and time on a 0.25° × 0.25° × 1-hourly grid as a function of reanalysis-derived predictor parameters, selected following an ingredients-based approach. The resulting hail models outperform the Significant Hail Parameter and the simulated climatological spatial distributions and annual cycles of lightning and hail are consistent with observations from storm report databases, radar, and lightning detection data. As a corollary result, CAPE released above the -10°C isotherm was found to be a more universally skilful predictor for large hail than CAPE. In the period 1950–2021, the models applied to the ERA5 reanalysis indicate significant increases of lightning and hail across most of Europe, primarily due to rising low-level moisture. The strongest modelled hail increases occur in northern Italy with increasing rapidity after 2010. Here, very large hail has become 3 times more likely than it was in the 1950s. Across North America trends are comparatively small, apart from isolated significant increases in the direct lee of the Rocky Mountains and across the Canadian Plains. In the southern Plains, a period of enhanced storm activity occurred in the 1980s and 1990s.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49549926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Simulating Wintertime Orographic Cloud Seeding over the Snowy Mountains of Australia 澳大利亚雪山上空冬季地形云播种模拟

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-06 DOI: 10.1175/jamc-d-23-0012.1

Sisi Chen, L. Xue, S. Tessendorf, Thomas H. Chubb, Andrew Peace, Luis Ackermann, Artur Gevorgyan, Yi Huang, S. Siems, Roy Rasmussen, Suzanne Kenyon, Johanna Speirs

{"title":"Simulating Wintertime Orographic Cloud Seeding over the Snowy Mountains of Australia","authors":"Sisi Chen, L. Xue, S. Tessendorf, Thomas H. Chubb, Andrew Peace, Luis Ackermann, Artur Gevorgyan, Yi Huang, S. Siems, Roy Rasmussen, Suzanne Kenyon, Johanna Speirs","doi":"10.1175/jamc-d-23-0012.1","DOIUrl":"https://doi.org/10.1175/jamc-d-23-0012.1","url":null,"abstract":"\u0000This study presents the first numerical simulations of seeded clouds over the Snowy Mountains of Australia. WRF-WxMod®, a novel glaciogenic cloud seeding model, was utilized to simulate the cloud response to winter orographic seeding under various meteorological conditions. Three cases during the 2018 seeding periods were selected for model evaluation, coinciding with an intensive ground-based measurement campaign. The campaign data were used for model validation and evaluation.\u0000Comparisons between simulations and observations demonstrate that the model realistically represents cloud structures, liquid water path, and precipitation. Sensitivity tests were performed to pinpoint key uncertainties in simulating natural and seeded clouds and precipitation processes. They also shed light on the complex interplay between various physical parameters/processes and their interaction with large-scale meteorology.\u0000Our study found that in unseeded scenarios, the warm and cold biases in different initialization datasets can heavily influence the intensity and phase of natural precipitation. Secondary ice production via Hallett-Mossop processes exerts a secondary influence. On the other hand, the seeding impacts are primarily sensitive to aerosol conditions and the natural ice nucleation process. Both factors alter the supercooled liquid water availability and the precipitation phase, consequently impacting the AgI nucleation rate. Furthermore, model sensitivities were inconsistent across cases, indicating no single model configuration optimally represents all three cases. This highlights the necessity of employing an ensemble approach for a more comprehensive and accurate assessment of the seeding impact.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49410492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Large-eddy Simulations of the Tropical Cyclone Boundary Layer at Landfall in an Idealized Urban Environment 理想城市环境下登陆时热带气旋边界层的大涡模拟

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-06 DOI: 10.1175/jamc-d-23-0024.1

C. Rozoff, David S. Nolan, George H. Bryan, Eric A. Hendricks, J. Knievel

{"title":"Large-eddy Simulations of the Tropical Cyclone Boundary Layer at Landfall in an Idealized Urban Environment","authors":"C. Rozoff, David S. Nolan, George H. Bryan, Eric A. Hendricks, J. Knievel","doi":"10.1175/jamc-d-23-0024.1","DOIUrl":"https://doi.org/10.1175/jamc-d-23-0024.1","url":null,"abstract":"\u0000Populated urban areas along many coastal regions are vulnerable to landfalling tropical cyclones (TCs). To the detriment of surface parameterizations in mesoscale models, the complexities of turbulence at high TC wind speeds in urban canopies are presently poorly understood. Thus, this study explores impacts of urban morphology on TC-strength winds and boundary layer turbulence in landfalling TCs. To better quantify how urban structures interact with TC winds, large-eddy simulations (LES) are conducted with the Cloud Model 1 (CM1). This implementation of CM1 includes immersed boundary conditions (IBCs) to represent buildings and eddy recycling to maintain realistic turbulent flow perturbations. Within the IBCs, an idealized coastal city with varying scales is introduced. TC winds impinge perpendicular to the urbanized coastline. The numerical experiments show that buildings generate distinct, intricate flow patterns that vary significantly as the city structure is varied. Urban IBCs produce much stronger turbulent kinetic energy than is produced by conventional surface parameterizations. Strong effective eddy viscosity due to resolved eddy mixing is displayed in the wake of buildings within the urban canopy, while deep and enhanced effective eddy viscosity is present downstream. Such effects are not seen in a comparison LES simulation using a simple surface parameterization with high roughness values. Wind tunneling effects in streamwise canyons enhance pedestrian-level winds well beyond what is possible without buildings. In the arena of regional mesoscale modeling, this type of LES framework with IBCs can be used to improve parameters in surface and boundary layer schemes to more accurately represent the drag coefficient and the eddy viscosity in landfalling TC boundary layers.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44500207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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: 1

The Macro- and Microphysical Response Characteristics of the Multicell Hailstorm Hail-Suppression Operation: Case Study 多细胞冰雹降雹行动的宏观和微观物理响应特征:个案研究

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-01 DOI: 10.1175/jamc-d-22-0129.1

Yuan Lu, Yunjun Zhou, Shuping Zou, Zhe Yang, Yong Zeng

{"title":"The Macro- and Microphysical Response Characteristics of the Multicell Hailstorm Hail-Suppression Operation: Case Study","authors":"Yuan Lu, Yunjun Zhou, Shuping Zou, Zhe Yang, Yong Zeng","doi":"10.1175/jamc-d-22-0129.1","DOIUrl":"https://doi.org/10.1175/jamc-d-22-0129.1","url":null,"abstract":"\u0000This study analyzed the macro- and microphysical response characteristics of a typical multicell hailstorm after seeding on 27 April 2019 in Weining, China, using X-band dual-polarization radar (YLD1-D) data. An improved X-pol hydrometeor identification algorithm was employed for hydrometeor identification. According to the diffusion of the seeding agents, the seeded hailstorm was graded into three study regions, and the evolution of the seeded hailstorm was divided into four periods. The response characteristics of the seeded hailstorm in each region and period were compared and analyzed. The results show that 1) macroscopically, the decrease in the reflectivity and the height of strong echo mainly occurred in the seeded period, whereas the decrease in the echo top and the height of the storm was mainly in the postseeded period; the echo height variation of the unseeded hailstorm is obviously different from that of the seeded hailstorm; and 2) from the microscopic perspective, the decrease in low-density graupel and supercooled water and the increase in ice crystals and aggregates in the seeded region mainly occurred in the seeded period, which was consistent with the time required for the “benefit competition” after the silver iodide completed nucleation. When compared with the seeded region, the hydrometeors in the unseeded region had an opposite trend (or an in-phase trend with an obviously lower changing rate), which further indicated the impact of the artificial ice nuclei on microphysical processes in the seeded region. For hailstorms with a high content of supercooled droplets and graupel, the key mechanisms of hail suppression are “cloud water glaciation,” “beneficial competition,” and “early rainout.”","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45001410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Equity, Inclusion, and Justice: An Opportunity for Action for AMS Publications Stakeholders 公平，包容和正义:AMS出版物利益相关者的行动机会

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-09-01 DOI: 10.1175/jamc-d-23-0135.1

引用次数: 0

Narrowing the Blind Zone of the GPM Dual-Frequency Precipitation Radar to Improve Shallow Precipitation Detection in Mountainous Areas 缩小GPM双频降水雷达盲区改进山区浅层降水探测

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-08-25 DOI: 10.1175/jamc-d-22-0162.1

Riku Shimizu, S. Shige, T. Iguchi, Cheng‐Ku Yu, Lin-Wen Cheng

{"title":"Narrowing the Blind Zone of the GPM Dual-Frequency Precipitation Radar to Improve Shallow Precipitation Detection in Mountainous Areas","authors":"Riku Shimizu, S. Shige, T. Iguchi, Cheng‐Ku Yu, Lin-Wen Cheng","doi":"10.1175/jamc-d-22-0162.1","DOIUrl":"https://doi.org/10.1175/jamc-d-22-0162.1","url":null,"abstract":"\u0000The Dual-frequency Precipitation Radar (DPR), which consists of a Ku-band precipitation radar (KuPR) and a Ka-band precipitation radar (KaPR), onboard the GPM Core Observatory cannot observe precipitation at low altitudes near the ground contaminated by surface clutter. This near-surface region is called the blind zone. DPR estimates the clutter free bottom (CFB) which is the lowest altitude not included in the blind zone, and estimates precipitation at altitudes higher than the CFB. High CFBs, which are common over mountainous areas, represent obstacles to detection of shallow precipitation and estimation of low-level enhanced precipitation. We compared KuPR data with rain gauge data from the Da-Tun Mountain of northern Taiwan acquired from March 2014 to February 2020. A total of 12 cases were identified in which the KuPR missed some rainfall with intensity of >10 mm h−1 that was observed by rain gauges. Comparison of KuPR profile and ground-based radar profile revealed that shallow precipitation in the KuPR blind zone was missed because the CFB was estimated to be higher than the lower bound of the range free from surface echoes. In the original operational algorithm, CFB was estimated using only the received power data of the KuPR. In this study, the CFB was identified by the sharp increase in the difference between the received powers of the KuPR and the KaPR at altitude affected by surface clutter. By lowering the CFB, the KuPR succeeded in detection and estimation of shallow precipitation.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43825858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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: 1

Multiple Markov Chains for Categorial Drought Prediction on United States Drought Monitor at Weekly Scale 美国干旱监测系统周尺度分类干旱预测的多重马尔可夫链

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-08-22 DOI: 10.1175/jamc-d-23-0061.1

Junjie Cao, Fu Guan, Xiang Zhang, Won-Ho Nam, G. Leng, Haoran Gao, Qingqing Ye, Xihui Gu, J. Zeng, Xu Zhang, Tailai Huang, D. Niyogi

{"title":"Multiple Markov Chains for Categorial Drought Prediction on United States Drought Monitor at Weekly Scale","authors":"Junjie Cao, Fu Guan, Xiang Zhang, Won-Ho Nam, G. Leng, Haoran Gao, Qingqing Ye, Xihui Gu, J. Zeng, Xu Zhang, Tailai Huang, D. Niyogi","doi":"10.1175/jamc-d-23-0061.1","DOIUrl":"https://doi.org/10.1175/jamc-d-23-0061.1","url":null,"abstract":"\u0000Predicting drought severity is essential for drought management and early warning systems. Although numerous physical model-based and data-driven methods have been put forward for drought prediction, their abilities are largely constrained by data requirements and modeling complexity. There remains a challenging task to efficiently predict categorial drought, especially for the United States Drought Monitor (USDM). Aiming at this issue, multiple Markov chains for USDM based categorial drought prediction are successfully proposed and evaluated in this paper. In particular, this study concentrated on how the Markov order, step size, and training set length affected prediction accuracy (PA). According to the experiments from 2000 to 2021, it was found the one-step and first-order Markov models had the best accuracy in predicting droughts up to 4 weeks ahead. The PA steadily dropped with increasing step scale, and the average accuracy at monthly scale was 88%. In terms of seasonal variability, summer (July-August) had the lowest PA while winter had the highest (January-February). In comparison to the western region, the PA in the eastern US is 25% higher. Moreover, the length of the training set had obvious impact on the PA of the model. The PA in one-step prediction was 87% and 78% under 20-year and 5-year training sets respectively. The results of the study showed that Markov models predicted categorical drought with high accuracy in the short term and showed different performances on time and space scales. Proper use of Markov models would help disaster managers and policymakers to put mitigation policies and measures into practice.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45638414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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: 1

Vertical Motions in Orographic Cloud Systems over the Payette River Basin. Part 4: Controls on Supercooled Liquid Water Content and Cloud Droplet Number Concentrations 帕耶特河流域地形云系统的垂直运动。第4部分:过冷液态水含量和云滴数浓度的控制

IF 3 3区地球科学

Journal of Applied Meteorology and Climatology Pub Date : 2023-08-10 DOI: 10.1175/jamc-d-23-0080.1

T. J. Zaremba, R. Rauber, B. Geerts, J. French, S. Tessendorf, L. Xue, K. Friedrich, C. Weeks, R. Rasmussen, M. Kunkel, D. Blestrud

{"title":"Vertical Motions in Orographic Cloud Systems over the Payette River Basin. Part 4: Controls on Supercooled Liquid Water Content and Cloud Droplet Number Concentrations","authors":"T. J. Zaremba, R. Rauber, B. Geerts, J. French, S. Tessendorf, L. Xue, K. Friedrich, C. Weeks, R. Rasmussen, M. Kunkel, D. Blestrud","doi":"10.1175/jamc-d-23-0080.1","DOIUrl":"https://doi.org/10.1175/jamc-d-23-0080.1","url":null,"abstract":"\u0000This paper examines the controls on supercooled liquid water content (SLWC) and drop number concentrations (Nt,CDP) over the Payette River Basin during the SNOWIE campaign. During SNOWIE, 27.4% of 1 Hz in situ cloud droplet probe samples were in an environment containing supercooled liquid water (SLW). The interquartile range of SLWC, when present, was found to be 0.02-0.18 g m−3, and 13.3−37.2 cm−3 for Nt,CDP, with the most extreme values reaching 0.40−1.75 g m−3 and 150−320 cm−3 in isolated regions of convection and strong shear-induced turbulence. SLWC and Nt,CDP distributions are shown to be directly related to cloud top temperature and ice particle concentrations, consistent with past research over other mountain ranges. Two classes of vertical motions were analyzed as potential controls on SLWC and Nt,CDP, the first forced by the orography and fixed in space relative to the topography (stationary waves), and the second transient, triggered by vertical shear and instability within passing synoptic-scale cyclones. SLWC occurrence and magnitudes, and Nt,CDP associated with fixed updrafts were found to be normally distributed about ridgelines when SLW was present. SLW was more likely to form at low altitudes near the terrain slope associated with fixed waves due to higher mixing ratios and larger vertical air parcel displacements at low altitudes. When considering transient updrafts, SLWC and Nt,CDP appear more uniformly distributed over the flight track with little discernable terrain dependence as a result of time and spatially varying updrafts associated with passing weather systems. The implications for cloud seeding over the basin are discussed.","PeriodicalId":15027,"journal":{"name":"Journal of Applied Meteorology and Climatology","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43487705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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