scholarly journals Technology of AIRS/AMSU/ATMS satellite data processing

2021 ◽  
Author(s):  
E.Yu. Mordvin ◽  
A.A. Lagutin ◽  
A.I. Revyakin
Keyword(s):  
Gaussian Function ◽  
Longwave Radiation ◽  
Passage Time ◽  
Advanced Technology ◽  
Strong Wind ◽  
Radiance Temperature ◽  
Software Library ◽  
Atmospheric Infrared Sounder ◽  
Processing Scheme ◽  
The Difference

The Atmospheric Infrared Sounder (AIRS) is a hyperspectral instrument with 2378 channels. It is a part of the Aqua space platform equipment. It registers outgoing longwave radiation in the IR-band from 3.74 to 15.4 microns. To correctly retrieve the atmospheric profiles in the presence of cloud structures, AIRS measurement processing scheme uses data from the 15-channel AMSU-A microwave instrument, which is also installed on Aqua. The paper proposes a technology for synthesizing the readings of AMSU-A, that failed in the fall of 2015, by using observations from the 22-channel radiometer of the Advanced Technology Microwave Sounder (ATMS) installed on Suomi-NPP and NOAA-20 satellites. These platforms were launched in 2011 and 2018, respectively. The transition between the coordinate grids of the two instruments was implemented by the “resample” software library, which transferred the radiance temperature values obtained by ATMS radiometer to the AMSU-A irregular measurement grid by means of a Gaussian function. The method was tested for the Aqua and Suomi-NPP neighboring orbits of 2015, when AMSU-A was still operating normally. It is established that the root-mean-square deviation of the radiance temperature values during the transferring of ATMS data to the AMSU-A coordinate grid does not exceed 1%, and the correlation coefficient is 0.98. Using the synthesized AMSU-A readings, reconstructions of the parameters of the atmosphere and the underlying surface were carried out. The analysis of the obtained results showed the suitability of the proposed method of replacing the microwave data from AMSU by the data from ATMS instruments. It should be noted that in the case of a rapidly changing atmosphere, for example, with a strong wind, the use of ATMS observations is possible only if the difference in the passage time of the two satellites does not exceed 10–15 minutes.

scholarly journals Assessing Stability of CERES-FM3 Daytime Longwave Unfiltered Radiance with AIRS Radiances

2012 ◽  
Vol 29 (3) ◽  
pp. 375-381 ◽  
Author(s):  
Xianglei Huang ◽  
Norman G. Loeb ◽  
Huiwen Chuang
Keyword(s):  
Radiant Energy ◽  
Longwave Radiation ◽  
Energy System ◽  
Atmospheric Infrared Sounder ◽  
Clear Sky ◽  
The Difference ◽  
Spectrally Resolved ◽  
Independent Assessment ◽  
Flight Model ◽  
Bound Estimation

Abstract Clouds and the Earth’s Radiant Energy System (CERES) daytime longwave (LW) radiances are determined from the difference between a total (TOT) channel (0.3–200 μm) measurement and a shortwave (SW) channel (0.3–5 μm) measurement, while nighttime LW radiances are obtained directly from the TOT channel. This means that a drift in the SW channel or the SW portion of the TOT channel could impact the daytime longwave radiances, but not the nighttime ones. This study evaluates daytime and nighttime CERES LW radiances for a possible secular drift in CERES LW observations using spectral radiances observed by Atmospheric Infrared Sounder (AIRS). By examining the coincidental AIRS and CERES Flight Model 3 (FM3) measurements over the tropical clear-sky oceans for all of January and July months since 2005, a secular drift of about −0.11% yr−1 in the daytime CERES-FM3 longwave unfiltered radiance can be identified in the CERES Single Scanner Footprint (SSF) Edition 2 product. This provides an upper-bound estimation for the drift in daytime outgoing longwave radiation, which is approximately −0.323 W m−2 yr−1. This estimation is consistent with the independent assessment concluded by the CERES calibration team. Such secular drift has been greatly reduced in the latest CERES SSF Edition 3 product. Comparisons are conducted for the CERES window channel as well, and it shows essentially no drift. This study serves as a practical example illustrating how the measurements of spectrally resolved radiances can be used to help evaluate data products from other narrowband or broadband measurements.

scholarly journals The influence of observed and modelled net longwave radiation on the rate of estimated potential evapotranspiration

2019 ◽  
Vol 67 (3) ◽  
pp. 280-288 ◽  
Author(s):  
Jitka Kofroňová ◽  
Miroslav Tesař ◽  
Václav Šípek
Keyword(s):  
Czech Republic ◽  
Solar Radiation ◽  
Potential Evapotranspiration ◽  
Sunshine Duration ◽  
Longwave Radiation ◽  
Radiation Balance ◽  
Parameter Calibration ◽  
Atmospheric Emissivity ◽  
The Bohemian Forest ◽  
The Difference

Abstract Longwave radiation, as part of the radiation balance, is one of the factors needed to estimate potential evapotranspiration (PET). Since the longwave radiation balance is rarely measured, many computational methods have been designed. In this study, we report on the difference between the observed longwave radiation balance and modelling results obtained using the two main procedures outlined in FAO24 (relying on the measured sunshine duration) and FAO56 (based on the measured solar radiation) manuals. The performance of these equations was evaluated in the April–October period over eight years at the Liz experimental catchment and grass surface in the Bohemian Forest (Czech Republic). The coefficients of both methods, which describe the influence of cloudiness factor and atmospheric emissivity of the air, were calibrated. The Penman-Monteith method was used to calculate the PET. The use of default coefficient values gave errors of 40–100 mm (FAO56) and 0–20 mm (FAO24) for the seasonal PET estimates (the PET was usually overestimated). Parameter calibration decreased the FAO56 error to less than 20 mm per season (FAO24 remained unaffected by the calibration). The FAO56 approach with calibrated coefficients proved to be more suitable for estimation of the longwave radiation balance.

scholarly journals Behavior and Energy Losses of Cows during the Period of Low Temperatures

2021 ◽  
Vol 24 (5) ◽  
pp. 46-53
Author(s):  
Oleksandr O. Borshch ◽  
Oleksandr V. Borshch ◽  
Yurii Mashkin ◽  
Vasyl Malina ◽  
Maxim Fedorchenko
Keyword(s):  
Low Temperatures ◽  
Heat Insulation ◽  
Energy Losses ◽  
Strong Wind ◽  
The Past ◽  
Air Temperatures ◽  
The Difference ◽  
And Behavior ◽  
Positive Effect ◽  
Moderate Climate

Over the past 20 years, dairy farms in Ukraine have been actively introducing the keeping of cows in easy-to-assemble premises. However, in a moderate climate (with four distinct year seasons), the issues of microclimate, energy losses of animals and their behavior during the cold period of the year for keeping in such premises have not been fully studied. The purpose of this work was to study the influence of the heat insulation elements use of side curtains in easy-to-assemble premises during the period of low temperatures on microclimate, energy outgoings for thermoregulation and behavior of cows. The research conducted in the central part of Ukraine (Kyiv region). The research was conducted during January-February (29-43 days of the year) 2021. This period characterized by low average daily temperatures of -12.2– -18.7°С, strong wind gusts and daily precipitation in the form of snow. Two easy-toassemble premises for 400 heads were used for research. Parameters of placements (LxWxH): 150х32х10.5 m. The first one was without the use of curtains heat insulation elements, and the second one was with these elements of heat insulation. It was found that the use of polycarbonate wall heat insulation elements had a positive effect on the microclimate in the placement during the period of low temperatures. Indicators of average daily air temperatures in the placement were 3.2 and 8.8°C higher compared to the temperature in the same premise without the use of heat insulation elements and the environment. The wind speed also differed by 0.18 and 11.04 m/s, respectively. In addition, the heat insulation of the walls affected the temperature under the lying cow (+1.8°C), energy outgoings for thermoregulation (-1.93 MJ) and the number of cows that lay in the period of the lowest temperatures (+3.23-9.83%) compared to the placement without heat insulation elements. The difference in temperature of rubber carpet in the compared premises was significant: +3.3°C in the premises with heat insulation elements compared to the premises without heat insulation

scholarly journals Improvements to the Geostationary Visible Imager Ray-Matching Calibration Algorithm for CERES Edition 4

2016 ◽  
Vol 33 (12) ◽  
pp. 2679-2698 ◽  
Author(s):  
David R. Doelling ◽  
Conor O. Haney ◽  
Benjamin R. Scarino ◽  
Arun Gopalan ◽  
Rajendra Bhatt
Keyword(s):  
Dynamic Range ◽  
Spectral Band ◽  
Radiant Energy ◽  
Convective Cloud ◽  
Energy System ◽  
Processing Scheme ◽  
Matching Algorithm ◽  
Cloud Properties ◽  
Calibration Algorithm ◽  
The Difference

AbstractThe Clouds and the Earth’s Radiant Energy System (CERES) project relies on geostationary imager–derived TOA broadband fluxes and cloud properties to account for the regional diurnal fluctuations between the Terra and Aqua CERES and MODIS measurements. The CERES project employs a ray-matching calibration algorithm in order to transfer the Aqua MODIS calibration to the geostationary (GEO) imagers, thereby allowing the derivation of consistent fluxes and cloud retrievals across the 16 GEO imagers utilized in the CERES record. The CERES Edition 4 processing scheme grants the opportunity to recalibrate the GEO record using an improved GEO/MODIS all-sky ocean ray-matching algorithm. Using a graduated angle matching method, which is most restrictive for anisotropic clear-sky ocean radiances and least restrictive for isotropic bright cloud radiances, reduces the bidirectional bias while preserving the dynamic range. Furthermore, SCIAMACHY hyperspectral radiances are used to account for both the solar incoming and Earth-reflected spectra in order to correct spectral band differences. As a result, the difference between the linear regression offset and the maintained GEO space count was reduced, and the calibration slopes computed from the linear fit and the regression through the space count agreed to within 0.4%. A deep convective cloud (DCC) ray-matching algorithm is also presented. The all-sky ocean and DCC ray-matching timeline gains are within 0.7% of one another. Because DCC are isotropic and the brightest, Earth targets with near-uniform visible spectra, the temporal standard error of GEO imager gains, are reduced by up to 60% from that of all-sky ocean targets.

scholarly journals Effects of Drifting Snow on Surface Radiation Budget in the Katabatic Wind Zone, Antarctica

1985 ◽  
Vol 6 ◽  
pp. 238-241 ◽  
Author(s):  
Takashi Yamanouchi ◽  
Sadao Kawaguchi
Keyword(s):  
Wind Speed ◽  
Longwave Radiation ◽  
Surface Radiation ◽  
Radiative Properties ◽  
Radiation Budget ◽  
Katabatic Wind ◽  
Drifting Snow ◽  
Radiation Fluxes ◽  
Snow Drift ◽  
The Difference

Effects of drifting snow are examined from measurements of radiation fluxes at Mizuho Station in the katabatic wind zone, Antarctica. A good correlation is found between the difference of downward longwave fluxes measured at two heights and wind speed used as an index of drifting snow. The wind increases the downward flux at a rate of 2 W m-2/m s-2 when wind speed is higher than 13 m/s. Drifting snow suppresses the net longwave cooling at the surface. Direct solar radiation is depleted greatly by the drifting snow; however, the global flux decreases only slightly, compensated by the large increase of the diffuse flux, at a rate of about 1% for each 1 m/s increase in wind speed. At Mizuho Station, the effect on longwave radiation prevails throughout the year. The relation between snow drift content and wind speed is obtained from shortwave optical depth measurements as a function of wind speed. A simple parameterization of radiative properties is given.

scholarly journals Study of outgoing longwave radiation anomalies associated with Haiti earthquake

2010 ◽  
Vol 10 (10) ◽  
pp. 2169-2178 ◽  
Author(s):  
P. Xiong ◽  
X. H. Shen ◽  
Y. X. Bi ◽  
C. L. Kang ◽  
L. Z. Chen ◽  
...  
Keyword(s):  
Outgoing Longwave Radiation ◽  
Longwave Radiation ◽  
Earthquake Precursor ◽  
Field Calculation ◽  
Haiti Earthquake ◽  
Time And Space ◽  
Temporal Continuity ◽  
Eddy Field ◽  
The Difference ◽  
Seismic Anomalies

Abstract. The paper presents an analysis by using the methods of Eddy field calculation mean and wavelet maxima to detect seismic anomalies within the outgoing longwave radiation (OLR) data based on time and space. The distinguishing feature of the method of Eddy field calculation mean is that we can calculate "the total sum of the difference value" of "the measured value" between adjacent points, which could highlight the singularity within data. The identified singularities are further validated by wavelet maxima, which using wavelet transformations as data mining tools by computing the maxima that can be used to identify obvious anomalies within OLR data. The two methods has been applied to carry out a comparative analysis of OLR data associated with the earthquake recently occurred in Haiti on 12 January 2010. Combining with the tectonic explanation of spatial and temporal continuity of the abnormal phenomena, the analyzed results have indicated a number of singularities associated with the possible seismic anomalies of the earthquake and from the comparative experiments and analyses by using the two methods, which follow the same time and space, we conclude that the singularities observed from 19 to 24 December 2009 could be the earthquake precursor of Haiti earthquake.

scholarly journals The Effect of Diurnal Sea Surface Temperature Warming on Climatological Air–Sea Fluxes

2013 ◽  
Vol 26 (8) ◽  
pp. 2546-2556 ◽  
Author(s):  
Carol Anne Clayson ◽  
Alec S. Bogdanoff
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Heat Budget ◽  
Longwave Radiation ◽  
Heat Fluxes ◽  
Sea Surface ◽  
Diurnal Variability ◽  
Diurnal Warming ◽  
Yearly Average ◽  
The Difference

Abstract Diurnal sea surface warming affects the fluxes of latent heat, sensible heat, and upwelling longwave radiation. Diurnal warming most typically reaches maximum values of 3°C, although very localized events may reach 7°–8°C. An analysis of multiple years of diurnal warming over the global ice-free oceans indicates that heat fluxes determined by using the predawn sea surface temperature can differ by more than 100% in localized regions over those in which the sea surface temperature is allowed to fluctuate on a diurnal basis. A comparison of flux climatologies produced by these two analyses demonstrates that significant portions of the tropical oceans experience differences on a yearly average of up to 10 W m−2. Regions with the highest climatological differences include the Arabian Sea and the Bay of Bengal, as well as the equatorial western and eastern Pacific Ocean, the Gulf of Mexico, and the western coasts of Central America and North Africa. Globally the difference is on average 4.45 W m−2. The difference in the evaporation rate globally is on the order of 4% of the total ocean–atmosphere evaporation. Although the instantaneous, year-to-year, and seasonal fluctuations in various locations can be substantial, the global average differs by less than 0.1 W m−2 throughout the entire 10-yr time period. A global heat budget that uses atmospheric datasets containing diurnal variability but a sea surface temperature that has removed this signal may be underestimating the flux to the atmosphere by a fairly constant value.

Integration of Network Resources Based on Unified Identity Authentication

2014 ◽  
Vol 623 ◽  
pp. 258-261
Author(s):  
Pei Ying Fan ◽  
Yang Qiu
Keyword(s):  
Governance Structure ◽  
Advanced Technology ◽  
Network Resources ◽  
Teaching Resources ◽  
Network Teaching ◽  
Main Research ◽  
Article Analysis ◽  
The Difference ◽  
Set Up ◽  
Unified Authentication

This article analysis the current situation of the virtual construction in university, which information non-sharing, poor safety and difficult management. Aiming at data diversification and the difference between platform, develop tools and system, making every network teaching resources system as an “information islet”, thus cause the disperse and independence of resources and data, integrate each resources system effectively by looking for a service governance structure. We proposed management system and method for private universities of long-term development. The main research is to set up the unified authentication system which can complete unified authentication and authority and administer. Using the virtual server technology, Information Office will set up a virtual campus portal platform with unified planning and concentration deployment, which is simple operation, advanced technology, safe and reliable, to realize unified management and guarantee the information resources interoperability and consistency.

Longwave Radiation Corrections for the OMNI Buoy Network

2021 ◽  
Keyword(s):  
Indian Ocean ◽  
Longwave Radiation ◽  
Field Measurements ◽  
North Indian Ocean ◽  
Shortwave Radiation ◽  
Data Logger ◽  
Clear Sky ◽  
The Difference ◽  
Radiation Measurements ◽  
Moored Buoy

Abstract The inception of a moored buoy network in the northern Indian Ocean in 1997 paved the way for systematic collection of longterm time series observations of meteorological and oceanographic parameters. This buoy network was revamped in 2011 with OMNI (Ocean Moored buoy Network for north Indian Ocean) buoys fitted with additional sensors to better quantify the air-sea fluxes. An inter-comparison of OMNI buoy measurements with the nearby WHOI mooring during the year 2015 revealed an overestimation of downwelling longwave radiation (LWR↓). Analysis of the OMNI and WHOI radiation sensors at a test station at NIOT during 2019 revealed that the accurate and stable amplification of the thermopile voltage records along with the customized data logger in the WHOI system results in better estimations of LWR↓. The offset in NIOT measured LWR↓ is estimated firstly by segregating the LWR↓ during clear sky conditions identified using the downwelling shortwave radiation measurements from the same test station, and secondly, finding the offset by taking the difference with expected theoretical clear sky LWR↓. The corrected LWR↓ exhibited good agreement with that of collocated WHOI measurements, with a correlation of 0.93. This method is applied to the OMNI field measurements and again compared with the nearby WHOI mooring measurements, exhibiting a better correlation of 0.95. This work has led to the revamping of radiation measurements in OMNI buoys and provides a reliable method to correct past measurements and improve estimation of air-sea fluxes in the Indian Ocean.

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