Study of seasonal trend in the difference between radiosonde and microwave soundings of tropospheric temperature

Ground-based microwave radiometers are increasingly used in operational meteorology and nowcasting. These instruments continuously measure the spectra of downwelling atmospheric radiation in the range 20–60 GHz used for the retrieval of tropospheric temperature and water vapor profiles. Spectroscopic uncertainty is an important part of the retrieval error budget, as it leads to systematic bias. In this study, we analyze the difference between observed and simulated microwave spectra obtained from more than four years of microwave and radiosonde observations over Nizhny Novgorod (56.2° N, 44° E). We focus on zenith-measured and elevation-scanning data in clear-sky conditions. The simulated spectra are calculated by a radiative transfer model with the use of radiosonde profiles and different absorption models, corresponding to the latest spectroscopy research. In the case of zenith-measurements, we found a systematic bias (up to ~2 K) of simulated spectra at 51–54 GHz. The sign of bias depends on the absorption model. A thorough investigation of the error budget points to a spectroscopic nature of the observed differences. The dependence of the results on the elevation angle and absorption model can be explained by the basic properties of radiative transfer and by cloud contamination at elevation angles.

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The Effect of Hydrometeors on MSU/AMSU Temperature Observations over the Tropical Ocean

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-17-0190.1 ◽

2018 ◽

Vol 35 (5) ◽

pp. 1141-1150 ◽

Cited By ~ 1

Author(s):

Hamid A. Pahlavan ◽

Qiang Fu ◽

John M. Wallace

Keyword(s):

Regression Coefficient ◽

Temperature Fields ◽

Tropospheric Temperature ◽

Tropical Ocean ◽

Microwave Sounding Unit ◽

Mean Fields ◽

Microwave Sounding ◽

Temperature Observations ◽

The Difference ◽

Grid Points

AbstractThe temperature of Earth’s atmosphere has been monitored continuously since late 1978 by the Microwave Sounding Unit (MSU) and the Advanced Microwave Sounding Unit (AMSU) flown on polar-orbiting weather satellites. It is well known that these measurements are affected by the scattering and emission from hydrometeors, including cloud water, precipitation, and ice particles. In this study the hydrometeor effects on MSU/AMSU temperature observations are investigated by comparing satellite-observed temperature of the middle troposphere (TMT) with synthetic TMT constructed using temperature fields from ECMWF Interim [ERA-Interim (ERA-I)]. Precipitation data have been used to estimate how much of the difference between these two TMT fields is due to hydrometeor contamination effects. It is shown that there exists a robust linear proportionality between TMT deficit (i.e., the measured TMT minus the synthetic TMT) and precipitation at individual grid points in monthly mean fields. The linear correlation is even stronger in the annual mean and seasonally varying climatology and also in the spatial pattern of ENSO-related anomalies. The linear regression coefficient obtained in all of these analyses is virtually identical: −0.042 K (mm day−1)−1. The channel that senses lower-tropospheric temperature (TLT) is more sensitive to precipitation than the TMT channel: the regression coefficient is −0.059 K (mm day−1)−1. It is shown that correcting the TMT or TLT monthly anomalies by removing the hydrometeor contamination does not significantly influence estimates of tropical mean temperature trends, but it could affect the pattern of temperature trend over the tropical oceans.

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Comparison and Calculation of Different Atmospheric Delay Models Using Atmospheric Parameters of VLBI Stations of China

Symposium - International Astronomical Union ◽

10.1017/s0074180900173231 ◽

1993 ◽

Vol 156 ◽

pp. 212-212

Author(s):

Zhigen Yang

Keyword(s):

Elevation Angle ◽

Mapping Function ◽

Physical Models ◽

Lapse Rate ◽

Tropospheric Temperature ◽

Atmospheric Parameters ◽

Temperature Lapse Rate ◽

Atmospheric Delay ◽

Vlbi Observations ◽

The Difference

The values of the atmospheric time delay for the “Chao”, “Marini” and “CfA−2.2” mapping function are calculated by using the atmospheric parameters in summer and winter at Shanghai, Kunming and Urumqi station respectively. A comparison among these values shows that the derivations of “Marini” from “Chao” and “CfA” are relatively large. On the other hand, the difference of values between the “Chao” and the “CfA” in the case of ∊ = 40° ∼ 10°, which is the average for the three stations, is from +1 mm to +47 mm for the “wet” part of the delay in summer, while is from −2 mm to −28 mm for the “dry” part in winter. For the case of low elevation angle ɛ ≐ 5°, the difference for the “wet” part can be about 400 mm in summer. Therefore, it is indispensable to make a further comparison between “Chao” and “CfA” mapping function by using the data of VLBI observations, in order to make a better revision to the adopted models of atmospheric delay.The monthly averages of the height of tropopause ht and the tropospheric temperature lapse rate βt for the three stations mentioned above are used to calculate the dry atmospheric delay by the “CfA” mapping function. The results show that the amplitudes of the annual changing of delay dτa, which is caused by ht and βt for the case of ∊ = 20° ∼ 10° at Urumqi station, are about 1 ∼ 5 mm and 2 ∼ 15 mm respectively. Therefore, taking the parameters of ht and βt of the stations into account in “CfA” model, instead of using fixed constants, would be much favourable for the requirements of 1 ps precision of VLBI physical models.

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Contribution Analysis of “Suroboyo Bus” in Waste Management Based on Two Form of Complete Fourier Series Estimator

Jurnal Matematika MANTIK ◽

10.15642/mantik.2021.7.1.86-95 ◽

2021 ◽

Vol 7 (1) ◽

pp. 86-95

Author(s):

M. Fariz Fadillah Mardianto ◽

Reynaldy Aries Ariyanto ◽

Raka Andriawan ◽

Devayanti Anugerahing Husada

Keyword(s):

Fourier Series ◽

Waste Management ◽

Goodness Of Fit ◽

Data Modeling ◽

Plastic Waste ◽

Seasonal Trend ◽

Percentage Contribution ◽

Contribution Analysis ◽

The Difference

Plastic waste is a problem that almost exists in all countries. This problem arises because of the lack of facilities that can handle the plastic waste. Suroboyo Bus is an innovation for this problem because Suroboyo Bus uses plastic bottles as payment. The purpose of this research is to predict the percentage contribution of Suroboyo Bus in handling plastic waste. The Fourier series estimator performs well for data modeling with seasonal trend patterns. This paper examines two approaches to the Fourier series. The difference between the approaches is the inclusion of the phi (π) function in the model. The result shows the goodness of fit criterion model with π function are for and 0,08% for MAPE whereas the fit criterion model without π function is 100% for and 0,07% for MAPE. In conclusion, the Fourier series model without the π function is better because the Fourier series model without the π function is more satisfy the goodness of fit criteria than the Fourier series model with the π.

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The incidence of Anoplocephaline cestodes in a population of rabbits in Surrey, England

Parasitology ◽

10.1017/s0031182000046576 ◽

1973 ◽

Vol 67 (3) ◽

pp. 351-364 ◽

Cited By ~ 9

Author(s):

A. R. Mead-Briggs ◽

J. A. Vaughan

Keyword(s):

Infection Rate ◽

Seasonal Trend ◽

The Other ◽

Intermediate Hosts ◽

Small Areas ◽

Low Level ◽

The Mean ◽

The Difference ◽

Host Infection

Samples of approximately five wild rabbits were obtained each week over the 4-year period 1967–70, and their intestines examined for adult tapeworms. Pour species of anoplocephalinae were found, Cittotaenia pectinata, C. denticulata, C. ctenoides and Andrya cuniculi. C. pectinata was found in 29% of the 968 rabbits examined, C. denticulata in 14%, C. ctenoides in 12% and A. cuniculi in 6%. There were 63 double infections, of which 44 involved A. cuniculi, and three triple infections. The most frequent number of worms per infection was one for C. pectinata and A. cuniculi and two for C. denticulata and C. clenoides, although the mean numbers for these species were respectively 7·2, 5·3, 2·7 and 1·8. A. cuniculi, and to a lesser extent C. ctenoides, were very restricted in distribution within the study area, occurring only on the higher, chalk downland (250–550 ft A.S.L.). This finding implies that individual rabbits usually spend their lives within relatively small areas. Considering all the material a seasonal trend in host infection rate was apparent only with C. denticulata, which increased in abundance from July to a peak in September and then declined gradually to a low level, lasting from April to June. Infections, including small specimens of any of the four species, were rare from February to June and it is presumed that infected intermediate hosts were correspondingly rare during this period. Except for C. denticulata, which was found more frequently in male rabbits than females, the sex of the host had no influence on its likelihood of infection. However, except for C. pectinata, the age of the host was important. Thus, C. denticulata and A. cuniculi were significantly more frequent in juveniles than adults whilst the reverse was true for C. ctenoides. Small (‘young’) specimens of C. denticulata and A. cuniculi were more frequent in juvenile than adult rabbits, but the difference was not significant for the other two species. It is concluded that only C. ctenoides survives for more than a year and that this species and C. pectinata are more likely to infect rabbits that are adult than are the other two species.

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Abstract 18: Seasonal Characteristic Of Kawasaki Disease With The Onset At The Different Seasons

Circulation ◽

10.1161/circ.131.suppl_2.18 ◽

2015 ◽

Vol 131 (suppl_2) ◽

Author(s):

Yukie Ozeki ◽

Fumiya Yamada ◽

Tsuyoshi Kishimoto ◽

Yosikazu Nakamura

Keyword(s):

Kawasaki Disease ◽

Serum Albumin ◽

Epidemiologic Study ◽

Seasonal Trend ◽

Albumin Concentration ◽

Female Ratio ◽

Number Of Patients ◽

Different Seasons ◽

Patient Groups ◽

The Difference

Background: Kawasaki disease (KD) has been diagnosed in more than 60 countries. Seasonal trend of the patients with KD is observed in many countries. Little is known about the difference between the patient groups in the term of high incidence. Objective: The aim of this study was to characterize the two patient groups during the winter and summer seasons in Japan. Methods: Epidemiologic characteristics were compared between January and July, through the 22th nationwide survey included patients who visited hospitals during 2011-2012. The proportions of survey items were observed by age-adjustment. Results: The total number of patients during 2011-12 was 26,691, the number of patients was 2812 in January and 2302 in July, and the male/female ratio was 1.4, respectively. The patients <3 years account for 66% of each group (1854/2812, 1530/2302). The proportion of <8 months of age was 13.0% (365/2812) in January, 17.8% (409/2302) in July, that of 15 months to 3 years was 38.8% (1092/2812), and 33.5% (771/2302). Concurrence with the diagnostic guidelines was examined, the typical cases in July were 1.6% lower than in January, and the suspected cases were 1.3% higher than in January. The suspected cases of less than 4 principle symptoms had 5.3% higher than in January. The treatment cases with γ-globulin started within 5 days of illness were 2.2% less than in July. The cases of cardiac sequelae (giant aneurysm, aneurysm, dilatation, and stenosis) were 0.3% higher than in July. The cases of serum albumin concentration less than 3.2g/dL were 3.6% higher than in July. The percentage of occurrence cardiac sequelae in this class was 9.5% higher than in July. Discussion: The difference in age distribution in the two patient groups diagnosed in January and July was observed. The symptom had a slight difference, too. These result do not contradict a hypothesis that onset of KD is concerned with plural infections with different seasonal trend and targeting for the specific age. The association between low levels of serum albumin and cardiac sequelae has been known. The association between this class and the patients in the specific season will be clear in future epidemiologic study. Conclusion: This study clarified part of the characteristic of the patient diagnosed in the different seasons.

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The Dependence of ITCZ Structure on Model Resolution and Dynamical Core in Aquaplanet Simulations

Journal of Climate ◽

10.1175/jcli-d-13-00269.1 ◽

2014 ◽

Vol 27 (6) ◽

pp. 2375-2385 ◽

Cited By ~ 28

Author(s):

Kiranmayi Landu ◽

L. Ruby Leung ◽

Samson Hagos ◽

V. Vinoj ◽

Sara A. Rauscher ◽

...

Keyword(s):

High Resolution ◽

Large Scale ◽

Convective Available Potential Energy ◽

Specific Humidity ◽

Tropospheric Temperature ◽

Dynamical Core ◽

Community Atmosphere Model ◽

Double Itcz ◽

Lateral Extent ◽

The Difference

Abstract Aquaplanet simulations using the Community Atmosphere Model, version 4 (CAM4), with the Model for Prediction Across Scales–Atmosphere (MPAS-A) and High-Order Method Modeling Environment (HOMME) dynamical cores and using zonally symmetric sea surface temperature (SST) structure are studied to understand the dependence of the intertropical convergence zone (ITCZ) structure on resolution and dynamical core. While all resolutions in HOMME and the low-resolution MPAS-A simulations give a single equatorial peak in zonal mean precipitation, the high-resolution MPAS-A simulations give a double ITCZ with precipitation peaking around 2°–3° on either side of the equator. This study reveals that the structure of ITCZ is dependent on the feedbacks between convection and large-scale circulation. It is shown that the difference in specific humidity between HOMME and MPAS-A can lead to different latitudinal distributions of the convective available potential energy (CAPE) by influencing latent heat release by clouds and the upper-tropospheric temperature. With lower specific humidity, the high-resolution MPAS-A simulation has CAPE increasing away from the equator that enhances convection away from the equator and, through a positive feedback on the circulation, results in a double ITCZ structure. In addition, it is shown that the dominance of antisymmetric waves in the model is not enough to cause double ITCZ, and the lateral extent of equatorial waves does not play an important role in determining the width of the ITCZ but rather the latter may influence the former.

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Precipitation frequency in MED and EURO-CORDEX ensembles from 0.44° to convective permitting resolution: what explains the differences?

10.5194/egusphere-egu21-8843 ◽

2021 ◽

Author(s):

Minh Ha-Truong ◽

Sophie Bastin ◽

Philippe Drobinski ◽

Lluís Fita ◽

Marjolaine Chiriaco ◽

...

Keyword(s):

Deep Convection ◽

Convective Precipitation ◽

Lower Probability ◽

Tropospheric Temperature ◽

Mountain Areas ◽

Precipitation Frequency ◽

Data Set ◽

The Mediterranean ◽

The Difference ◽

The Impact

<p>Dynamical models are a major tool for studying climate variability and its evolution. But despite the refinements in resolution and efforts to revise the dynamical and physical processes, rainfall extremes are still poorly represented, even at regional scales. Recent studies using convection-permitting simulations have demonstrated the improvement in representing heavy rainfall. In this study, we investigate the impacts of different model resolutions and convection representations (parameterized vs. explicit) in simulating precipitation frequency over Europe and the Mediterranean and try to explain the difference between model ensembles by focusing on triggering processes. For this purpose, we used a multi-model data-set with three different resolutions (0.44&#176;, 0.11&#176; and 0.0275&#176;) produced in the context of the MED and EURO-CORDEX and the CORDEX Flagship Pilot Study on convection (FPSCONV). At 0.0275&#176;, deep convection is explicitly represented while at 0.44&#176; and 0.11&#176;, it is parameterized with different schemes. In addition, to partially separate the impact of the higher resolution and convective schemes, we remapped the outputs of resolution 0.0275&#176; to the 0.11&#176; grid. To explain the difference in simulating precipitation frequency, a multi-variate approach is applied, in which precipitation is considered in the statistical relationship with tropospheric temperature and humidity - derived from colocated observations at the supersite SIRTA near Paris and some GPS stations. The results show that precipitation frequency in the higher resolution simulations is reduced because of a lower probability to exceed the critical value of integrated water vapor (IWVcv) over which precipitation picks up for different temperature bins. At low temperature, the probability decreases mostly due to a different humidity distribution in high resolution simulations, but for the temperature bins where the dominant precipitation type changes to convective precipitation, the decrease of probability to exceed IWVcv is mainly explained by a higher value of IWVcv. In these bins, the differences between 0.0275&#176; and 0.44&#176;, 0.11&#176; resolutions become larger over southern Europe and the Mediterranean. This is not clear over mountain areas, where processes of triggering are more linked to orography than convection. Our results also suggest a decrease of model spread at higher temperature, and a stronger impact of switching off convective schemes than increasing resolution.</p>

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The sensitivity of simulated aerosol climatic impact to domain size using regional model (WRF-Chem v3.6)

Geoscientific Model Development ◽

10.5194/gmd-15-199-2022 ◽

2022 ◽

Vol 15 (1) ◽

pp. 199-218

Author(s):

Xiaodong Wang ◽

Chun Zhao ◽

Mingyue Xu ◽

Qiuyan Du ◽

Jianqiu Zheng ◽

...

Keyword(s):

Asian Summer Monsoon ◽

Eastern China ◽

Great Influence ◽

Lower Troposphere ◽

Domain Size ◽

Regional Modeling ◽

Tropospheric Temperature ◽

Climatic Impact ◽

The Difference ◽

Induced Changes

Abstract. Domain size can have significant impact on regional modeling results, but few studies examined the sensitivities of simulated aerosol impact to regional domain size. This study investigates the regional modeling sensitivities of aerosol impact on the East Asian summer monsoon (EASM) to domain size. The simulations with two different domain sizes demonstrate consistently that aerosols induce the cooling of the lower troposphere that leads to the anticyclone circulation anomalies and thus the weakening of EASM moisture transport. The aerosol-induced adjustment of monsoonal circulation results in an alternate increase and decrease pattern of precipitation over China. Domain size has a great influence on the simulated meteorological fields. For example, the simulation with larger domain size produces weaker EASM circulation, which also affects aerosol distributions significantly. This leads to the difference of simulated strength and area extent of aerosol-induced changes of lower-tropospheric temperature and pressure, which further results in different distributions of circulation and precipitation anomalies over China. For example, over southeastern China, aerosols induce the increase (decrease) of precipitation from the smaller-domain (larger-domain) simulation. Different domain sizes consistently simulate an aerosol-induced increase in precipitation around 30∘ N over eastern China. This study highlights the important influence of domain size on regional modeling results of aerosol impact on circulation and precipitation, which may not be limited to East Asia. More generally, this study also implies that proper modeling of meteorological fields with appropriate domain size is one of the keys to simulating robust aerosol climatic impact.

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Epidemiological and demographic characteristics of dengue and chikungunya infections over five years from 2014-2018, in Tamil Nadu, India

International Journal of Community Medicine and Public Health ◽

10.18203/2394-6040.ijcmph20211747 ◽

2021 ◽

Vol 8 (5) ◽

pp. 2287

Author(s):

Dhanalakshmi Velusamy ◽

Suriakumar Jayakumar ◽

Varatharaj Ramakrishnan ◽

Rajamannar Veeramanoharan ◽

Bhavna Gupta ◽

...

Keyword(s):

Trend Analysis ◽

Tamil Nadu ◽

Viral Infections ◽

Health Department ◽

The State ◽

Seasonal Trend ◽

Serum Samples ◽

The People ◽

Males And Females ◽

The Difference

Background: An epidemiological, demographic and seasonal trend analysis of dengue and chikungunya seroprevalence was performed in five districts of Tamil Nadu during 2014-2018.Methods: Serum samples from the suspected patients were screened using IgM antibody ELISA.Results: Dengue and chikungunya seropositivity ranged from 17.9-68.2% and 14.9-58.3%, respectively. Dengue cases were reported in all the years with a spike in 2017. Highest number of chikungunya cases was in 2018. Dengue cases peaked in the cooler months following monsoon while chikungunya data for seasonal trend analysis was not sufficient. Both viral infections were found common in the people >12 years, however, the difference of cases between males and females was not statistically significant.Conclusions: The findings of this study indicate that both chikungunya and dengue are actively circulating in the state and the state health department needs to direct their efforts not only to control the spread but also on the future preparedness to prevent outbreaks.

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