Journal of Atmospheric and Oceanic Technology最新文献_第9页

A Precise Zenith Hydrostatic Delay Calibration Model in China Based on Nonlinear Least Square Method 基于非线性最小二乘法的中国天顶静压延迟精确校准模型

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-23 DOI: 10.1175/jtech-d-22-0111.1

Kaiyun Lv, Weifeng Yang, Zhiping Chen, Pengfei Xia, Xiaoxing He, Zhigao Chen, Tieding Lu

{"title":"A Precise Zenith Hydrostatic Delay Calibration Model in China Based on Nonlinear Least Square Method","authors":"Kaiyun Lv, Weifeng Yang, Zhiping Chen, Pengfei Xia, Xiaoxing He, Zhigao Chen, Tieding Lu","doi":"10.1175/jtech-d-22-0111.1","DOIUrl":"https://doi.org/10.1175/jtech-d-22-0111.1","url":null,"abstract":"\u0000Zenith Hydrostatic Delay (ZHD) is a crucial parameter in Global Navigation Satellite System (GNSS) navigation and positioning and GNSS meteorology. Since Saastamoinen ZHD model has a larger error in China, it is significant to improve the Saastamoinen ZHD model. This work firstly estimated the Saastamoinen model using the integrated ZHD as reference values obtained from radiosonde data collected at 73 stations in China from 2012 to 2016. Then, the residuals between the reference values and the Saastamoinen modeled ZHDs were calculated, the correlations between the residuals and meteorological parameters were explored. The continuous wavelet transform method was used to recognize the annual and semi-annual characteristics of the residuals. Because of the nonlinear variation characteristics of residuals, the nonlinear least square estimation method was introduced to establish an improved ZHD model-China Revised Zenith Hydrostatic Delay (CRZHD) adapted for China. The accuracy of CRZHD model was assessed using radiosonde data and IGS (International GNSS Service, IGS) data in 2017, the radiosonde data results show that CRZHD model is superior to Saastamoinen model with a 69.6% improvement. The three IGS stations with continuous meteorological data present that the BIAS/RMSE are decreased by 2.7 /1.5 (URUM), 5.9 /5.3 (BJFS) and 9.6 /8.8 mm (TCMS). The performance of the CRZHD model retrieving PWV was discussed using radiosonde data in 2017. It is shown that the CRZHD model retrieving PWV (CRZHD-PWV) outperforms Saastamoinen model (SAAS-PWV), which the precision is improved by 44.4%. The BIAS ranged from -1 to 1 mm and RMSE ranged from 0 to 2 mm in CRZHD-PWV account for 89.0%/95.9%, while SAAS-PWV account for 46.6%/ 58.9%.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42481250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Effects of Spatial Interpolation on a Novel, Dual-Doppler 3D Wind Retrieval Technique 空间插值对一种新的双多普勒三维风反演技术的影响

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-19 DOI: 10.1175/jtech-d-23-0004.1

Jordan Brook, A. Protat, C. Potvin, J. Soderholm, H. McGowan

引用次数: 1

Scripps Argo Trajectory-Based Velocity Product: Global Estimates of Absolute Velocity Derived from Core, Biogeochemical, and Deep Argo Float Trajectories at Parking Depth 基于Scripps-Argo轨迹的速度乘积：从堆芯、生物地球化学和深Argo漂浮轨迹得出的绝对速度的全球估计

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-19 DOI: 10.1175/jtech-d-22-0065.1

N. Zilberman, M. Scanderbeg, A. Gray, P. Oke

引用次数: 1

Quantifying Daytime Heating Biases in Marine Air Temperature Observations from Ships 量化船舶海洋气温观测中的日间加热偏差

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-18 DOI: 10.1175/jtech-d-22-0080.1

T. Cropper, D. Berry, R. Cornes, Elizabeth C. Kent

{"title":"Quantifying Daytime Heating Biases in Marine Air Temperature Observations from Ships","authors":"T. Cropper, D. Berry, R. Cornes, Elizabeth C. Kent","doi":"10.1175/jtech-d-22-0080.1","DOIUrl":"https://doi.org/10.1175/jtech-d-22-0080.1","url":null,"abstract":"\u0000Marine air temperatures recorded on ships during the daytime are known to be biased warm on average due to energy storage by the superstructure of the vessels. This makes unadjusted daytime observations unsuitable for many applications including for the monitoring of long-term temperature change over the oceans. In this paper a physics-based approach is used to estimate this heating bias in ship observations from ICOADS. Under this approach, empirically determined coefficients represent the energy transfer terms of a heat budget model which quantifies the heating bias and is applied as a function of cloud cover and the relative wind speed over individual ships. The coefficients for each ship are derived from the anomalous diurnal heating relative to nighttime air temperature. Model coefficients, cloud cover and relative wind speed are then used to estimate the heating bias ship-by-ship and generate nighttime-equivalent time series. A variety of methodological approaches were tested. Application of this method enables the inclusion of some daytime observations in climate records based on marine air temperatures, allowing an earlier start date and giving an increase in spatial coverage compared to existing records that exclude daytime observations.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47574740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Experimental Validation of Float Array Tidal Current Measurements in Agate Pass, WA 浮子阵列在WA玛瑙关潮汐测量的实验验证

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-12 DOI: 10.1175/jtech-d-22-0034.1

T. Harrison, Nate Clemett, B. Polagye, J. Thomson

{"title":"Experimental Validation of Float Array Tidal Current Measurements in Agate Pass, WA","authors":"T. Harrison, Nate Clemett, B. Polagye, J. Thomson","doi":"10.1175/jtech-d-22-0034.1","DOIUrl":"https://doi.org/10.1175/jtech-d-22-0034.1","url":null,"abstract":"\u0000Tidal currents, particularly in narrow channels, can be challenging to characterize due to high current speeds (> 1 m s−1), strong spatial gradients, and relatively short synoptic windows. To assess tidal currents in Agate Pass, WA, we cross-evaluated data products from an array of acoustically-tracked underwater floats and from acoustic Doppler current profilers (ADCPs) in both station-keeping and drifting modes. While increasingly used in basin-scale science, underwater floats have seen limited use in coastal environments. This study presents the first application of a float array towards small-scale (< 1 km), high resolution (< 5 m) measurements of mean currents in energetic tidal channel and utilizes a new prototype float, the µFloat, designed specifically for sampling in dynamic coastal waters. We show that a float array (20 floats) can provide data with similar quality to ADCPs, with measurements of horizontal velocity differing by less than 10% of nominal velocity, except during periods of low flow (0.1 m s−1). Additionally, floats provided measurements of the three dimensional temperature field, demonstrating their unique ability to simultaneously resolve in situ properties that cannot be remotely observed.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48026285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

A Neural Network-based Cloud Mask for PREFIRE and Evaluation with Simulated Observations 基于神经网络的预燃云掩模及模拟观测评估

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-10 DOI: 10.1175/jtech-d-22-0023.1

C. Bertossa, T. L’Ecuyer, A. Merrelli, Xianglei Huang, Xiuhong Chen

{"title":"A Neural Network-based Cloud Mask for PREFIRE and Evaluation with Simulated Observations","authors":"C. Bertossa, T. L’Ecuyer, A. Merrelli, Xianglei Huang, Xiuhong Chen","doi":"10.1175/jtech-d-22-0023.1","DOIUrl":"https://doi.org/10.1175/jtech-d-22-0023.1","url":null,"abstract":"\u0000The Polar Radiant Energy in the Far InfraRed Experiment (PREFIRE) will fill a gap in our understanding of polar processes and the polar climate by offering widespread, spectrally-resolved measurements through the Far InfraRed (FIR) with two identical CubeSat spacecraft. While the polar regions are typically difficult for skillful cloud identification due to cold surface temperatures, the reflection by bright surfaces, and frequent temperature inversions, the inclusion of the FIR may offer increased spectral sensitivity, allowing for the detection of even thin ice clouds. This study assesses the potential skill, as well as limitations, of a neural network-based cloud mask using simulated spectra mimicking what the PREFIRE mission will capture. Analysis focuses on the polar regions. Clouds are found to be detected approximately 90% of time using the derived neural network. The NN’s assigned confidence for whether a scene is ‘clear’ or ‘cloudy’ proves to be a skillful way in which quality flags can be attached to predictions. Clouds with higher cloud top heights are typically more easily detected. Low-altitude clouds over polar surfaces, which are the most difficult for the NN to detect, are still detected over 80% of the time. The FIR portion of the spectrum is found to increase the detection of clear scenes and increase mid-to-high altitude cloud detection. Cloud detection skill improves through the use of the overlapping fields of view produced by the PREFIRE instrument’s sampling strategy. Overlapping fields of view increase accuracy relative to the baseline NN while simultaneously predicting on a sub-FOV scale.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47561150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 Mount Washington Observatory Regional Mesonet: A Technical Overview of a Mountain-Based Mesonet 华盛顿山天文台区域Mesonet:基于山的Mesonet的技术概述

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-06 DOI: 10.1175/jtech-d-22-0054.1

Brian Fitzgerald, J. Broccolo, K. Garrett

{"title":"The Mount Washington Observatory Regional Mesonet: A Technical Overview of a Mountain-Based Mesonet","authors":"Brian Fitzgerald, J. Broccolo, K. Garrett","doi":"10.1175/jtech-d-22-0054.1","DOIUrl":"https://doi.org/10.1175/jtech-d-22-0054.1","url":null,"abstract":"\u0000The Mount Washington Observatory Regional Mesonet (MWRM) is a network of 18 remote meteorological monitoring stations (as of 2022), including the Auto Road Vertical Profile (ARVP), located across the White Mountains of Northern New Hampshire. Each station measures temperature and relative humidity, with additional variables at many locations. All stations need to withstand the frequent combination of intense cold, high precipitation amounts, icing, and hurricane-force winds in a mountain environment. Due to these challenges, the MWRM employs rugged instrumentation, an innovative radio-communications relay approach, and carefully selected sites that balance ideal measuring environments with station survivability. Data collected from the MWRM are used operationally by forecasters (including Mount Washington Observatory and National Weather Service staff) to validate model guidance, by alpine and climate scientists, by recreationalists accessing conditions in the backcountry, by groups operating on the mountain (Cog Railway, toll Auto Road) and by search and rescue organizations. This paper provides a detailed description of the network, with emphasis on how the challenging climate and terrain of this mountain region impacts sensor selection, site maintenance and overall operation.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46069878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Updates on CYGNSS Ocean Surface Wind Validation in the Tropics CYGNSS热带海面风验证的最新进展

4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2023-01-01 DOI: 10.1175/jtech-d-21-0168.1

Shakeel Asharaf, Derek J. Posselt, Faozi Said, Christopher S. Ruf

{"title":"Updates on CYGNSS Ocean Surface Wind Validation in the Tropics","authors":"Shakeel Asharaf, Derek J. Posselt, Faozi Said, Christopher S. Ruf","doi":"10.1175/jtech-d-21-0168.1","DOIUrl":"https://doi.org/10.1175/jtech-d-21-0168.1","url":null,"abstract":"Abstract Global Navigation Satellite System Reflectometry (GNSS-R)-based wind retrieval techniques use the global positioning system (GPS) signals scattered from the ocean surface in the forward direction, and can potentially work in all weather conditions. An overview of recent progress made in the Cyclone Global Navigation Satellite System (CYGNSS) level-2 surface wind products is given. To this end, four publicly released CYGNSS surface wind products—Science Data Record (SDR) v2.1, SDR v3.0, Climate Data Record (CDR) v1.1, and science wind speed product NOAA v1.1—are validated quantitatively against high-quality data from tropical buoy arrays. The latest released CYGNSS wind products (e.g., CDR v1.1, SDR v3.0, NOAA v1.1), as compared with these tropical buoy data, significantly outperform the SDR v2.1. Moreover, the uncertainty among these products is found to be less than 2 m s −1 root-mean-squared difference, meeting the NASA science mission level-1 uncertainty requirement for wind speeds below 20 m s −1 . The quality of the CYGNSS wind is further assessed under different precipitation conditions in low winds, and in large-scale convective regions. Results show that the presence of rain appears to cause a slightly positive wind speed bias in all CYGNSS data. Nonetheless, the outcomes are encouraging for the recently released CYGNSS wind products in general, and for CYGNSS data in regions with precipitating deep convection. The overall comparison indicates a significant improvement in wind speed quality and sample size when going from the older version to any of the newer datasets.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136296842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 2

Application of Machine Learning Techniques to Ocean Mooring Time-Series Data 机器学习技术在海洋系泊时间序列数据中的应用

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2022-12-28 DOI: 10.1175/jtech-d-21-0183.1

B. Sloyan, C. Chapman, R. Cowley, A. Charantonis

{"title":"Application of Machine Learning Techniques to Ocean Mooring Time-Series Data","authors":"B. Sloyan, C. Chapman, R. Cowley, A. Charantonis","doi":"10.1175/jtech-d-21-0183.1","DOIUrl":"https://doi.org/10.1175/jtech-d-21-0183.1","url":null,"abstract":"\u0000In situ observations are vital to improving our understanding of the variability and dynamics of the ocean. A critical component of the ocean circulation are the strong, narrow and highly variable western boundary currents. Ocean moorings that extend from the sea floor to the surface remain the most effective and efficient method to fully observe these currents. For various reasons mooring instruments may not provide continuous records. Here we assess the application of the Iterative Completion Self Organising Maps (ITCOMPSOM) machine learning technique to fill observational data gaps in a 7.5 year time-series of the East Australian Current. The method was validated by withholding parts of fully known profiles, and reconstructing them. For 20% random withholding of known velocity data validation statistics of the u- and v-velocity components are R2 coefficients of 0.70 and 0.88 and, root mean square errors of 0.038 m s−1 and 0.064 m s−1, respectively. Withholding 100 days of known velocity profiles over a depth range between 60 m to 700 m has mean profile residual differences between true and predicted u- and v-velocity of 0.009 m s−1 and 0.02 m s−1, respectively. The ITCOMPSOM also reproduces the known velocity variability. For 20% withholding of temperature and salinity data root mean square error of 0.04 and 0.38°C, respectively, are obtained. The ITCOMPSOM validation statistics are significantly better than those obtained when standard data filling methods are used. We suggest that machine learning techniques can be an appropriate method to fill missing data and enable production of observational-derived data products.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2022-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49582257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Assessment of Atmospheric and Oceanographic Measurements from an Autonomous Surface Vehicle 自主水面飞行器的大气和海洋测量评估

IF 2.2 4区地球科学

Journal of Atmospheric and Oceanic Technology Pub Date : 2022-12-15 DOI: 10.1175/jtech-d-22-0060.1

A. Amador, S. Merrifield, E. Terrill

{"title":"Assessment of Atmospheric and Oceanographic Measurements from an Autonomous Surface Vehicle","authors":"A. Amador, S. Merrifield, E. Terrill","doi":"10.1175/jtech-d-22-0060.1","DOIUrl":"https://doi.org/10.1175/jtech-d-22-0060.1","url":null,"abstract":"\u0000The present work details the measurement capabilities ofWave Glider Autonomous Surface Vehicles (ASVs) for research-grade meteorology, wave, and current data. Methodologies for motion compensation are described and tested, including a correction technique to account for Doppler shifting of the wave signal. Wave Glider measurements are evaluated against observations obtained fromWorld Meteorological Organization (WMO)-compliant moored buoy assets located off the coast of Southern California. The validation spans a range of field conditions and includes multiple deployments to assess the quality of vehicle-based observations. Results indicate that Wave Gliders can accurately measure wave spectral information, bulk wave parameters, water velocities, bulk winds, and other atmospheric variables with the application of appropriate motion compensation techniques. Measurement errorswere found to be comparable to those from reference moored buoys and within WMO operational requirements. The findings of this study represent a step towards enabling the use of ASV-based data for the calibration and validation of remote observations and assimilation into forecast models.","PeriodicalId":15074,"journal":{"name":"Journal of Atmospheric and Oceanic Technology","volume":" ","pages":""},"PeriodicalIF":2.2,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44971506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 4