scholarly journals Impact of Long-Term Observation on the Sampling Characteristics of TRMM PR Precipitation

2017 ◽  
Vol 56 (3) ◽  
pp. 713-723 ◽  
Author(s):  
Masafumi Hirose ◽  
Yukari N. Takayabu ◽  
Atsushi Hamada ◽  
Shoichi Shige ◽  
Munehisa K. Yamamoto
Keyword(s):  
Sampling Error ◽  
Tropical Rainfall Measuring Mission ◽  
High Impact ◽  
Trmm Pr ◽  
Areal Fraction ◽  
Large Systems ◽  
Long Term Observation ◽  
Degree Of Similarity ◽  
Semiarid Tropics

AbstractObservations of the Tropical Rainfall Measuring Mission Precipitation Radar (TRMM PR) over 16 yr yielded hundreds of large precipitation systems (≥100 km) for each 0.1° grid over major rainy regions. More than 90% of the rainfall was attributed to large systems over certain midlatitude regions such as La Plata basin and the East China Sea. The accumulation of high-impact snapshots reduced the significant spatial fluctuation of the rain fraction arising from large systems and allowed the obtaining of sharp images of the geographic rainfall pattern. Widespread systems were undetected over low-rainfall areas such as regions off Peru. Conversely, infrequent large systems brought a significant percentage of rainfall over semiarid tropics such as the Sahel. This demonstrated an increased need for regional sampling of extreme phenomena. Differences in data collected over a period of 16 yr were used to examine sampling adequacy. The results indicated that more than 10% of the 0.1°-scale sampling error accounted for half of the TRMM domain even for a 10-yr data accumulation period. Rainfall at the 0.1° scale was negatively biased in the first few years for over more than half of the areas because of a lack of high-impact samples. The areal fraction of the 0.1°-scale climatology with a 50% accuracy exceeded 95% in the ninth year and in the fifth year for those areas with rainfall >2 mm day−1. A monotonic increase in the degree of similarity of finescale rainfall to the best estimate with an accuracy of 10% illustrated the need for further sampling.

scholarly journals Incidence-Angle Dependency of TRMM PR Rain Estimates

2012 ◽  
Vol 29 (2) ◽  
pp. 192-206 ◽  
Author(s):  
Masafumi Hirose ◽  
Shuji Shimizu ◽  
Riko Oki ◽  
Toshio Iguchi ◽  
David A. Short ◽  
...  
Keyword(s):  
Error Detection ◽  
Incidence Angle ◽  
Tropical Rainfall Measuring Mission ◽  
Global Precipitation Climatology Project ◽  
Residual Effects ◽  
Coherent Signals ◽  
Low Level ◽  
Multiple Sensors ◽  
Trmm Pr ◽  
Long Term Observation

Abstract The incidence-angle differences of estimated surface rainfall obtained from the precipitation radar (PR) on board the Tropical Rainfall Measuring Mission (TRMM) satellite were investigated. The bias before the orbit boost in August 2001 relative to the near-nadir statistics was 2.7% over the ocean and −5.8% over land. After the boost, the bias was −3.2% and −9.5%, respectively. These biases were further quantified with respect to error sources, that is, the beam mismatch correction error, detection capability of storms with low-level storm-top height, and residual effects. For shallow storms lower than 3 km, most incidence-angle differences were caused by main lobe contamination. For nonshallow storms, several error factors resulted in 5.3% overestimates over the ocean and 5.1% underestimates over land for the period before the boost. The remaining uncertainty in local low-level profiles was identified as a controversial issue. The bias-corrected dataset updates the interannual variation in rainfall obtained from the TRMM PR. The increasing rainfall features and recent high-rainfall years were consistent with prior studies based on other microwave sensors. The coherent signals and slight differences in the temporal variation compared with the Global Precipitation Climatology Project (GPCP) data indicate the importance of further internal and cross validations based on long-term observation by multiple sensors.

Morphology, Intensity, and Rainfall Production of MJO Convection: Observations from DYNAMO Shipborne Radar and TRMM

2015 ◽  
Vol 72 (2) ◽  
pp. 623-640 ◽  
Author(s):  
Weixin Xu ◽  
Steven A. Rutledge
Keyword(s):  
Mesoscale Convective System ◽  
Tropical Rainfall Measuring Mission ◽  
Radar Data ◽  
Convective System ◽  
Precipitation Radar ◽  
Convective Systems ◽  
Trmm Pr ◽  
Mesoscale Convective ◽  
Trmm Precipitation

Abstract This study uses Dynamics of the Madden–Julian Oscillation (DYNAMO) shipborne [Research Vessel (R/V) Roger Revelle] radar and Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) datasets to investigate MJO-associated convective systems in specific organizational modes [mesoscale convective system (MCS) versus sub-MCS and linear versus nonlinear]. The Revelle radar sampled many “climatological” aspects of MJO convection as indicated by comparison with the long-term TRMM PR statistics, including areal-mean rainfall (6–7 mm day−1), convective intensity, rainfall contributions from different morphologies, and their variations with MJO phase. Nonlinear sub-MCSs were present 70% of the time but contributed just around 20% of the total rainfall. In contrast, linear and nonlinear MCSs were present 10% of the time but contributed 20% and 50%, respectively. These distributions vary with MJO phase, with the largest sub-MCS rainfall fraction in suppressed phases (phases 5–7) and maximum MCS precipitation in active phases (phases 2 and 3). Similarly, convective–stratiform rainfall fractions also varied significantly with MJO phase, with the highest convective fractions (70%–80%) in suppressed phases and the largest stratiform fraction (40%–50%) in active phases. However, there are also discrepancies between the Revelle radar and TRMM PR. Revelle radar data indicated a mean convective rain fraction of 70% compared to 55% for TRMM PR. This difference is mainly due to the reduced resolution of the TRMM PR compared to the ship radar. There are also notable differences in the rainfall contributions as a function of convective intensity between the Revelle radar and TRMM PR. In addition, TRMM PR composites indicate linear MCS rainfall increases after MJO onset and produce similar rainfall contributions to nonlinear MCSs; however, the Revelle radar statistics show the clear dominance of nonlinear MCS rainfall.

scholarly journals SAT0137 Long-term observation of fibromyalgia patients

2001 ◽  
Author(s):  
L Szczepanski ◽  
C Stepniak ◽  
B Targonska-Stepniak
Keyword(s):  
Long Term Observation

scholarly journals Phenotype of the Aging-Dependent Spontaneous Onset of Hearing Loss in DBA/2 Mice

2021 ◽  
Vol 8 (3) ◽  
pp. 49
Author(s):  
Min-Soo Seo ◽  
Byeonghyeon Lee ◽  
Kyung-Ku Kang ◽  
Soo-Eun Sung ◽  
Joo-Hee Choi ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Early Stage ◽  
Auditory Brainstem ◽  
Dependent Manner ◽  
Intrinsic Properties ◽  
Hearing Ability ◽  
Brainstem Response ◽  
Long Term Observation ◽  
Spontaneous Onset

DBA/2 mice are a well-known animal model for hearing loss developed due to intrinsic properties of these animals. However, results on the phenotype of hearing loss in DBA/2 mice have been mainly reported at an early stage in mice aged ≤7 weeks. Instead, the present study evaluated the hearing ability at 5, 13, and 34 weeks of age using DBA/2korl mice. Auditory brainstem response test was performed at 8–32 KHz at 5, 13, and 34 weeks of age, and hearing loss was confirmed to be induced in a time-dependent manner. In addition, histopathological evaluation at the same age confirmed the morphological damage of the cochlea. The findings presented herein are the results of the long-term observation of the phenotype of hearing loss in DBA/2 mice and can be useful in studies related to aging-dependent hearing loss.

scholarly journals Posterior Uveal Effusion after Cataract Surgery

2021 ◽  
pp. 62-67
Author(s):  
Annegret Abaza ◽  
Özlem Dikmetas ◽  
Irmingard Neuhann ◽  
Faik Gelisken
Keyword(s):  
Cataract Surgery ◽  
Corticosteroid Therapy ◽  
Anterior Segment ◽  
Subretinal Fluid ◽  
Posterior Pole ◽  
Functional Improvement ◽  
Long Term Observation ◽  
The Right ◽  
Uveal Effusion

We report a case of posterior uveal effusion (UE) with a long-term follow-up that has occurred following cataract surgery. A 64-year-old woman presented with diminished vision of the right eye (RE) 3 weeks after an uneventful phacoemulsification and intraocular lens implantation. Complete ophthalmic examination including fluorescein angiography (FA), indocyanine green angiography (ICGA), echography and optical coherence tomography (OCT) were performed. Best corrected visual acuity (BCVA) of the RE was 20/50. Anterior segment and intraocular pressure were unremarkable. OCT revealed prominent folds of the choroid and retina, subretinal fluid and darkening of the choroid with reduced visibility of the choroidal vessels and the scleral border. The left eye (LE) was unremarkable. BCVA of the LE was: 20/20. After topical anti-inflammatory and systemic corticosteroid therapy for 5 months, no morphological change of the macula was seen. The patient was observed without any treatment. Forty-three months after the cataract surgery and 38 months after cessation of the corticosteroid therapy, OCT revealed a normal macular morphology and the BCVA improved to 20/25. Even though rare, UE at the posterior pole may occur after modern cataract surgery. OCT examination is a reliable tool in monitoring the macular morphology. Since morphological and functional improvement can be seen in long-term, observation may be considered for some cases of posterior UE with resistance to the therapy.

scholarly journals Atmospheric Thermal and Dynamic Vertical Structures of Summer Hourly Precipitation in Jiulong of the Tibetan Plateau

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 505
Author(s):  
Yonglan Tang ◽  
Guirong Xu ◽  
Rong Wan ◽  
Xiaofang Wang ◽  
Junchao Wang ◽  
...  
Keyword(s):  
Wind Speed ◽  
Tibetan Plateau ◽  
Precipitation Amount ◽  
Summer Precipitation ◽  
The Tibetan Plateau ◽  
Hourly Precipitation ◽  
Air Convection ◽  
Precipitation Variation ◽  
Long Term Observation

It is an important to study atmospheric thermal and dynamic vertical structures over the Tibetan Plateau (TP) and their impact on precipitation by using long-term observation at representative stations. This study exhibits the observational facts of summer precipitation variation on subdiurnal scale and its atmospheric thermal and dynamic vertical structures over the TP with hourly precipitation and intensive soundings in Jiulong during 2013–2020. It is found that precipitation amount and frequency are low in the daytime and high in the nighttime, and hourly precipitation greater than 1 mm mostly occurs at nighttime. Weak precipitation during the daytime may be caused by air advection, and strong precipitation at nighttime may be closely related with air convection. Both humidity and wind speed profiles show obvious fluctuation when precipitation occurs, and the greater the precipitation intensity, the larger the fluctuation. Moreover, the fluctuation of wind speed is small in the morning, large at noon and largest at night, presenting a similar diurnal cycle to that of convective activity over the TP, which is conductive to nighttime precipitation. Additionally, the inverse layer is accompanied by the inverse humidity layer, and wind speed presents multi-peaks distribution in its vertical structure. Both of these are closely related with the underlying surface and topography of Jiulong. More studies on physical mechanism and numerical simulation are necessary for better understanding the atmospheric phenomenon over the TP.

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