Growing Operational Use of FY-3 Data in the ECMWF System

This paper reviews the data quality and impact of observations from the FY-3 satellite series used operationally in the ECMWF system. This includes data from the passive microwave radiometers MWHS-1, MWHS-2 and MWRI, as well as observations from the radio occultation receiver GNOS. Evaluations against background equivalents show that the quality of the observations is broadly comparable to that of similar instruments on other polar-orbiting satellites, even though biases for the passive microwave observations can be somewhat larger and more complex for some channels. An observing system experiment shows that the FY-3 instruments jointly contribute significantly to the forecast skill in the ECMWF system. Positive impact of up to 2% is seen for most variables out to the day-2 forecasts over hemispheric scales, with significant benefits for total column water vapor or for temperature and wind in the stratosphere out to day 4.

Automated Soil Moisture Monitoring Wireless Sensor Network for Long-Term Cal/Val Applications

The design and development of a wireless sensor network for soil moisture measurement in an unlevelled 10 km × 10 km area, is described. It was specifically deployed for the characterization of a reference area, in campaigns of calibration and validation of the space mission SMOS (Soil Moisture and Ocean Salinity), but the system is easily extensible to monitor other climatic or environmental variables, as well as to other regions of ecological interest. The network consists of a number of automatic measurement stations, strategically placed following soil homogeneity and land uses criteria. Every station includes acquisition, conditioning and communication systems. The electronics are battery operated with the help of solar cells, in order to have a total autonomous system. The collected data is then transmitted through long radio links, with ling ranges above 8 km. A standard PC linked to internet is finally used in order to control the whole network, to store the data, and to allow the remote access to the real-time data.

Method study and uncertainty analysis of calibration coefficients validation based on the Inner Mongolia test site

Calibration coefficients validation is the foundation for ascertaining the sensor performance and carrying out the quantitative application.Based on the analysis of the differences between the calibration and validation,two calibration coefficients validation methods were introduced in this paper.Taking the HJ-1A satellite CCD1 camera as an example,the uncertainties of calibration coefficients validation were analyzed.The calibration coefficients validation errors were simulated based on the measured data at an Inner Mongolia test site.The result showed that in the large view angle,the ground directional reflectance variation and the atmospheric path variation were the main error sources in calibration coefficients validation.The ground directional reflectance correction and atmospheric observation angle normalization should be carried out to improve the validation accuracy of calibration coefficients.

Numerical modelling of reinforced concrete flexural members strengthened using textile reinforced mortars

Externally bonded(EB)and near-surface mounted(NSM)bonding are two widely adopted and researched strengthening methods for reinforced-concrete structures.EB composite substrates are easy to reach and repair using appropriate surface treatments,whereas NSM techniques can be easily applied to the soffit and concrete member sides.The EB bonded fiber-reinforced polymer(FRP)technique has a significant drawback:combustibility,which calls for external protective agents,and textile reinforced mortar(TRM),a class of EB composites that is noncombustible and provides a similar functionality to any EB FRP-strengthened substrate.This study employs a finite element analysis technique to investigate the failing failure of carbon textile reinforced mortar(CTRM)-strengthened reinforced concrete beams.The principal objective of this numerical study was to develop a finite element model and validate a set of experimental data in existing literature.A set of seven beams was modelled and calibrated to obtain concrete damage plasticity(CDP)parameters.The predicted results,which were in the form of load versus deflection,load versus rebar strain,tensile damage,and compressive damage patterns,were in good agreement with the experimental data.Moreover,a parametric study was conducted to verify the applicability of the numerical model and study various influencing factors such as the concrete strength,internal reinforcement,textile roving spacing,and externally-applied load span.The ultimate load and deflection of the predicted finite element results had a coefficient of variation(COV)of 6.02%and 5.7%,respectively.A strain-based numerical comparison with known methods was then conducted to investigate the debonding mechanism.The developed finite element model can be applied and tailored further to explore similar TRM-strengthened beams undergoing debonding,and the preventive measures can be sought to avoid premature debonding.

Evaluation of reference evapotranspiration methods for the northeastern region of India

The study planed to identify a suitable alternative to the FAO 56 Penman-Monteith(FAO56PM)equation for calculating reference evapotranspiration(ET_(0))from chosen te mperature and radiation based models utilizing monthly meteorological data from 30 destinations in diverse agro-ecologial regions of the Northeast(NE)India ie,Assam Bengal Plain(ABP),eastern Himalaya(EH),and the northeastern hilly(NEH)region.Radiation-based IRMAK3 most appropriate in the ABP(weighted root mean square deviation,WRMSD=0.17 mm d^(-1),r^(2)=0.98,for Nagrakata),and TURC model being in the first three rank of most of the sites,with the lowest error and highest correlation in NEH(WRMSD=0.10 mm d^(-1),r^(2)=0.92,for Shillong),and EH(WRMSD=0.23 mm d^(-1),r^(2)=-0.95,for Gangtok).Findings reveal that IRMAK3 and TURC models performed equally well and were observed to be the best among selected modets for the majority of stations followed by FAO24 Blaney-Criddle(FAO24BC),and 1957MAKK Pair-wise regession equations were developed for preferred FAO56PM ET_(0) estimates to ET_(0) estimates by alternative methods.Cross-correlation of eighteen chose methods demonstrated that the five equations(i.e.four radiation-and one temperature-based)performed eceptionally well when contrasted with the FAO56PM model,thus being advised for assessing ET_(0)。under limiting data conditions as have yielded a better estimate of ET_(0) with a small error.