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Ultrasonic hydrometer  


The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time "t" between the initial and returning impulses. Considering the distance "d" between the spaced sonic surfaces and the measured time "t", the sonic velocity "V" is calculated with the equation "V=2d/t". The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between and C. and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation. The disclosed modified battery has a hollow spacer nub on the battery side wall, the sonic surfaces being on the inside of the nub and the electrolyte filling between the surfaces to the exclusion of intervening structure. An accessible pad exposed on the nub wall opposite one sonic surface allows the reliable placement thereagainst of the transducer.

Swoboda, Carl A. (Naperville, IL)



Calibration of hydrometers  

Microsoft Academic Search

After a brief description of the different methods employed in periodic calibration of hydrometers used in most cases to measure the density of liquids in the range between 500 kg m-3 and 2000 kg m-3, particular emphasis is given to the multipoint procedure based on hydrostatic weighing, known as well as Cuckow's method. The features of the calibration apparatus and

Salvatore Lorefice; Andrea Malengo



The Great Hydrometer Construction Contest!  

ERIC Educational Resources Information Center

The relationship between specific gravity, salinity, and density in brine solutions is investigated. Students construct hydrometers to reinforce concepts learned in oceanography. Background information, salt requirements for the unknowns, directions, and reproducible worksheets are included. (KR)

McGinnis, James Randy; Padilla, Michael J.



Operational Hydromet Data Management System. Design Characteristics.  

National Technical Information Service (NTIS)

The hydromet system under development will include a central data bank operated by the U.S. Corps of Engineers, a large number of automated hydromet data gathering stations interfacing with the central data bank, and data retrieval facilities for interfac...



27 CFR 30.22 - Hydrometers and thermometers.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Hydrometers and thermometers. 30.22 Section 30.22 Alcohol...Instruments § 30.22 Hydrometers and thermometers. The hydrometers used...for gauging spirits. Hydrometers and thermometers shall be used and the true...



27 CFR 30.22 - Hydrometers and thermometers.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Hydrometers and thermometers. 30.22 Section 30.22 Alcohol...Instruments § 30.22 Hydrometers and thermometers. The hydrometers used...for gauging spirits. Hydrometers and thermometers shall be used and the true...



Ultrasonic hydrometer. [Specific gravity of electrolyte  


The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time t between the initial and returning impulses. Considering the distance d between the spaced sonic surfaces and the measured time t, the sonic velocity V is calculated with the equation V = 2d/t. The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between 0 and 40/sup 0/C and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation.

Swoboda, C.A.



27 CFR 30.23 - Use of precision hydrometers and thermometers.  

Code of Federal Regulations, 2010 CFR

...Use of precision hydrometers and thermometers. 30.23 Section 30.23...Use of precision hydrometers and thermometers. Care should be exercised to obtain accurate hydrometer and thermometer readings. In order to...



27 CFR 30.23 - Use of precision hydrometers and thermometers.  

Code of Federal Regulations, 2010 CFR

...Use of precision hydrometers and thermometers. 30.23 Section 30.23...Use of precision hydrometers and thermometers. Care should be exercised to obtain accurate hydrometer and thermometer readings. In order to...




Microsoft Academic Search

In a widely-used method for particle size analysis of soils, the weight percentages of sand, silt, and clay are calculated from the density of an aqueous soil suspension measured by hydrometer. There are many versions of the procedure, differing in the type of dispersing solution, the volume of the suspension, the time of settling before taking hydrometer readings, or in

John Ashworth; Doug Keyes; Rhonda Kirk; Robert Lessard



SHORT COMMUNICATION: An image processing approach to calibration of hydrometers  

Microsoft Academic Search

The usual method adopted for multipoint calibration of glass hydrometers is based on the measurement of the buoyancy by hydrostatic weighing when the hydrometer is plunged in a reference liquid up to the scale mark to be calibrated. An image processing approach is proposed by the authors to align the relevant scale mark with the reference liquid surface level. The

S. Lorefice; A. Malengo



Alignment of the Measurement Scale Mark during Immersion Hydrometer Calibration Using an Image Processing System  

PubMed Central

The present work presents an improved method to align the measurement scale mark in an immersion hydrometer calibration system of CENAM, the National Metrology Institute (NMI) of Mexico, The proposed method uses a vision system to align the scale mark of the hydrometer to the surface of the liquid where it is immersed by implementing image processing algorithms. This approach reduces the variability in the apparent mass determination during the hydrostatic weighing in the calibration process, therefore decreasing the relative uncertainty of calibration.

Pena-Perez, Luis Manuel; Pedraza-Ortega, Jesus Carlos; Ramos-Arreguin, Juan Manuel; Arriaga, Saul Tovar; Fernandez, Marco Antonio Aceves; Becerra, Luis Omar; Hurtado, Efren Gorrostieta; Vargas-Soto, Jose Emilio



Alignment of the measurement scale mark during immersion hydrometer calibration using an image processing system.  


The present work presents an improved method to align the measurement scale mark in an immersion hydrometer calibration system of CENAM, the National Metrology Institute (NMI) of Mexico, The proposed method uses a vision system to align the scale mark of the hydrometer to the surface of the liquid where it is immersed by implementing image processing algorithms. This approach reduces the variability in the apparent mass determination during the hydrostatic weighing in the calibration process, therefore decreasing the relative uncertainty of calibration. PMID:24284770

Pea-Perez, Luis Manuel; Pedraza-Ortega, Jesus Carlos; Ramos-Arreguin, Juan Manuel; Arriaga, Saul Tovar; Fernandez, Marco Antonio Aceves; Becerra, Luis Omar; Hurtado, Efren Gorrostieta; Vargas-Soto, Jose Emilio



Comparison of American Society of Testing Materials and Soil Science Society of America Hydrometer Methods for Particle-Size Analysis  

SciTech Connect

Particle-size analysis (PSA) is widely used in both soil science and geo-engineering. Soil classification schemes are built on PSA values while recent developments in pedotransfer functions rely on PSA to estimate soil hydraulic properties. Because PSA is method dependent, the standardization of experimental procedures is important for the comparison of reported results. A study was conducted to compare the American Society of Testing Materials (ASTM) hydrometer method (D422) for particle-size analysis with the hydrometer method published by the Soil Science Society of America (SSSA). Tests on soils ranging in texture from sand to a sandy clay loam were conducted at temperatures ranging from 20 C to 30 C. The main difference between methods is the temperature correction, with the ASTM method relying on an empirical correction and the SSSA method using a blank hydrometer reading. Identical texture estimates for all but one sample was observed between methods. Percent fines, silt, and clay demonstrated relatively consistent values between methods. D50 and D30 showed reasonable agreement between methods, with differences of less than 4 percent and 8 percent. For D10 values, the agreement was less satisfactory, with uncertainties of as much as 10 percent. The results suggest that ASTM and SSSA methods can be used interchangeably for textural analysis.

Keller, Jason M.; Gee, Glendon W.



KEY COMPARISON: EUROMET.M.DK4\\/EUROMET Project 702: Comparison of the calibrations of high-resolution hydrometers for liquid density determinations  

Microsoft Academic Search

The main objective of the EUROMET project 702 was to compare the extent of comparability among eleven participating European national metrology institutes (INRIM (IT), OMH (HU), PTB (DE), BEV (AT), IPQ (PT), LNE (FR), MIKES (FI), GUM (PL), SMU (SK), UME (TR) and VNIIM (RU)) in performing calibrations of high-resolution hydrometers for liquid density determination in the range between 600

S. Lorefice; A. Malengo; C. Vmossy; H. Bettin; H. Toth; M. do Cu Ferreira; A. Gosset; T. Madec; M. Heinonen; C. Buchner; E. Lenard; R. Spurny; U. Akcadag; N. Domostroeva



SUPPLEMENTARY COMPARISON: Report of the bilateral comparison of the calibrations of hydrometers for liquid density determination between CENAM-Mexico and INRIM-Italy: SIM.M.DS1  

Microsoft Academic Search

Hydrometers are instruments usually made of glass which are widely used for different levels of precision to measure liquid density and related quantities to control different products and processes. This bilateral comparison on the calibration of hydrometers shows that results reported by CENAM-Mexico and INRIM-Italy are consistent within the claimed uncertainty in the range of 800 kg\\/m3 to 1200 kg\\/m3.

Luis Omar Becerra; Salvatore Lorefice



Bilateral comparison on the calibrations of hydrometers for liquid density between INRIMItaly and INMETROBrazil: SIM.M.DS2  

Microsoft Academic Search

The results of the SIM.M.D-S2 bilateral comparison between INRIMItaly and INMETROBrazil are summarized in this report. The aims of this comparison were to check the stated uncertainty levels and the degrees of equivalence between the two institutes on the calibration of hydrometers for liquid density in the range of 800 kg m?3 to 1000 kg m?3 at 20 C, by

Salvatore Lorefice; Dalni Malta; Paulo Roberto Marteleto



SUPPLEMENTARY COMPARISON Bilateral comparison on the calibrations of hydrometers for liquid density between INRIM-Italy and INMETRO-Brazil: SIM.M.DS2  

Microsoft Academic Search

The results of the SIM.M.D-S2 bilateral comparison between INRIM-Italy and INMETRO-Brazil are summarized in this report. The aims of this comparison were to check the stated uncertainty levels and the degrees of equivalence between the two institutes on the calibration of hydrometers for liquid density in the range of 800 kg m-3 to 1000 kg m-3 at 20 C, by

Salvatore Lorefice; Dalni Malta; Jos Julio Pinheiro; Paulo Roberto Marteleto



Measurement of particle size distribution of soil and selected aggregate sizes using the hydrometer method and laser diffractometry  

NASA Astrophysics Data System (ADS)

Soil particle size distribution has been traditionally determined by the hydrometer or the sieve-pipette methods, both of them time consuming and requiring a relatively large soil sample. This might be a limitation in situations, such as for instance analysis of suspended sediment, when the sample is small. A possible alternative to these methods are the optical techniques such as laser diffractometry. However the literature indicates that the use of this technique as an alternative to traditional methods is still limited, because the difficulty in replicating the results obtained with the standard methods. In this study we present the percentages of soil grain size determined using laser diffractometry within ranges set between 0.04 - 2000 ?m. A Beckman-Coulter LS-230 with a 750 nm laser beam and software version 3.2 in five soils, representative of southern Spain: Alameda, Benacazn, Conchuela, Lanjarn and Pedrera. In three of the studied soils (Alameda, Benacazn and Conchuela) the particle size distribution of each aggregate size class was also determined. Aggregate size classes were obtained by dry sieve analysis using a Retsch AS 200 basic . Two hundred grams of air dried soil were sieved during 150 s, at amplitude 2 mm, getting nine different sizes between 2000 ?m and 10 ?m. Analyses were performed by triplicate. The soil sample preparation was also adapted to our conditions. A small amount each soil sample (less than 1 g) was transferred to the fluid module full of running water and disaggregated by ultrasonication at energy level 4 and 80 ml of sodium hexametaphosphate solution during 580 seconds. Two replicates of each sample were performed. Each measurement was made for a 90 second reading at a pump speed of 62. After the laser diffractometry analysis, each soil and its aggregate classes were processed calibrating its own optical model fitting the optical parameters that mainly depends on the color and the shape of the analyzed particle. As a second alternative a unique optical model valid for a broad range of soils developed by the Department of Soil, Water, and Environmental Science of the University of Arizona (personal communication, already submitted) was tested. The results were compared with the particle size distribution measured in the same soils and aggregate classes using the hydrometer method. Preliminary results indicate a better calibration of the technique using the optical model of the Department of Soil, Water, and Environmental Science of the University of Arizona, which obtained a good correlations (r2>0.85). This result suggests that with an appropriate calibration of the optical model laser diffractometry might provide a reliable soil particle characterization.

Guzmn, G.; Gmez, J. A.; Girldez, J. V.




Microsoft Academic Search

Laser diffraction method commonly used in many engineering and industrial fields such as ceramic, sand, clay, cement, abrasion, powder metallurgy, food, pharmacology, cosmetics, paint, and sedimentology has been used in geotechnical engineering field in recent years as an alternative of the hydrometer\\/pipette method. In this study, clay content of 72 natural soil samples taken from various locations of Turkey determined

Mustafa ZER


Optical-Type Hydrometer for Lead-Acid Batteries and its Applications  

Microsoft Academic Search

As the most widely used means to know the charged condition of a lead-acid battery, the method to measure the specific gravity of the electrolyte is adopted. Here we report in this paper on an optical-type sensor taking advantage of the fact that the sulfuric acid electrolyte has a certain definite refractive index in accordance with its specific gravity and

Yoshiki Nagai; Yasuharu Tomokuni; Tomoki Matsui



A High Resolution Hydrometer Phase Classifier Based on Analysis of Cloud Radar Doppler Spectra.  

SciTech Connect

The lifecycle and radiative properties of clouds are highly sensitive to the phase of their hydrometeors (i.e., liquid or ice). Knowledge of cloud phase is essential for specifying the optical properties of clouds, or else, large errors can be introduced in the calculation of the cloud radiative fluxes. Current parameterizations of cloud water partition in liquid and ice based on temperature are characterized by large uncertainty (Curry et al., 1996; Hobbs and Rangno, 1998; Intriery et al., 2002). This is particularly important in high geographical latitudes and temperature ranges where both liquid droplets and ice crystal phases can exist (mixed-phase cloud). The mixture of phases has a large effect on cloud radiative properties, and the parameterization of mixed-phase clouds has a large impact on climate simulations (e.g., Gregory and Morris, 1996). Furthermore, the presence of both ice and liquid affects the macroscopic properties of clouds, including their propensity to precipitate. Despite their importance, mixed-phase clouds are severely understudied compared to the arguably simpler single-phase clouds. In-situ measurements in mixed-phase clouds are hindered due to aircraft icing, difficulties distinguishing hydrometeor phase, and discrepancies in methods for deriving physical quantities (Wendisch et al. 1996, Lawson et al. 2001). Satellite-based retrievals of cloud phase in high latitudes are often hindered by the highly reflecting ice-covered ground and persistent temperature inversions. From the ground, the retrieval of mixed-phase cloud properties has been the subject of extensive research over the past 20 years using polarization lidars (e.g., Sassen et al. 1990), dual radar wavelengths (e.g., Gosset and Sauvageot 1992; Sekelsky and McIntosh, 1996), and recently radar Doppler spectra (Shupe et al. 2004). Millimeter-wavelength radars have substantially improved our ability to observe non-precipitating clouds (Kollias et al., 2007) due to their excellent sensitivity that enables the detection of thin cloud layers and their ability to penetrate several non-precipitating cloud layers. However, in mixed-phase clouds conditions, the observed Doppler moments are dominated by the highly reflecting ice crystals and thus can not be used to identify the cloud phase. This limits our ability to identify the spatial distribution of cloud phase and our ability to identify the conditions under which mixed-phase clouds form.

Luke,E.; Kollias, P.



Comparison of American Society of Testing Materials and Soil Science Society of America Hydrometer Methods for Particle-Size Analysis  

Microsoft Academic Search

Particle-size analysis (PSA) is widely used in both soil science and geo-engineering. Soil classification schemes are built on PSA values while recent developments in pedotransfer functions rely on PSA to estimate soil hydraulic properties. Because PSA is method dependent, the standardization of experimental procedures is important for the comparison of reported results. A study was conducted to compare the American

Jason M. Keller; Glendon W. Gee



27 CFR 30.61 - Table 1, showing the true percent of proof spirit for any indication of the hydrometer at...  

Code of Federal Regulations, 2010 CFR

...temperatures between zero and 100 degrees Fahrenheit. 30.61 Section 30.61 Alcohol...temperatures between zero and 100 degrees Fahrenheit. This table shows the true percent...temperatures between zero and 100 degrees Fahrenheit and shall be used in determining...



27 CFR 30.61 - Table 1, showing the true percent of proof spirit for any indication of the hydrometer at...  

Code of Federal Regulations, 2010 CFR

...temperatures between zero and 100 degrees Fahrenheit. 30.61 Section 30.61 Alcohol...temperatures between zero and 100 degrees Fahrenheit. This table shows the true percent...temperatures between zero and 100 degrees Fahrenheit and shall be used in determining...



27 CFR 30.64 - Table 4, showing the fractional part of a gallon per pound at each percent and each tenth percent...  

Code of Federal Regulations, 2013 CFR

...degrees Fahrenheit) of distilled spirits containing dissolved solids from the total weight of the liquid and its apparent proof (hydrometer...350 pounds of blended whisky containing added solids Temperature °F 75.0° Hydrometer...



76 FR 53403 - Foreign-Trade Zone 14-Little Rock, AR; Application for Subzone; Mitsubishi Power Systems Americas...  

Federal Register 2010, 2011, 2012, 2013

...hydraulic assemblies, accumulators, valves, bearings, housings, lighting equipment, windings, electronic components, thermometers, hydrometers, gauges, measuring instruments, heaters, thermostats, regulators, switches, lamps, clock...



21 CFR 146.140 - Pasteurized orange juice.  

Code of Federal Regulations, 2013 CFR

...quantity reasonably necessary to raise the Brix or the Brix-acid ratio to any point within the normal range usually...the Brix hydrometer reading to the grams of anhydrous citric acid per 100 milliliters of juice is not less than 10 to...



Factors Associated with Colostral Specific Gravity in Dairy Cows  

Microsoft Academic Search

The objectives of this study were to identify factors associated with colostral specific gravity in dairy cows, as measured by a commercially available hydrometer (Colostrometer). Colostral specific gravity was mea- sured in 1085 first-milking colostrum samples from 608 dairy cows of four breeds on a single farm during a 5- yr period. Effects of breed, lactation number, and month and

D. E. Morin; P. D. Constable; F. P. Maunsell; G. C. McCoy



Use of combined radar and radiometer systems in space for precipitation measurement: Some ideas  

NASA Technical Reports Server (NTRS)

A brief survey is given of some fundamental physical concepts of optimal polarization characteristics of a transmission path or scatter ensemble of hydrometers. It is argued that, based on this optimization concept, definite advances in remote atmospheric sensing are to be expected. Basic properties of Kennaugh's optimal polarization theory are identified.

Moore, R. K.



Particle-Size Analysis  

Microsoft Academic Search

Book Chapter describing methods of particle-size analysis for soils. Includes a variety of classification schemes. Standard methods for size distributions using pipet and hydrometer techniques are described. New laser-light scattering and related techniques are discussed. Complete with updated references.

Glendon W. Gee; Dani; G. C. Topp J. H. Dane



A Method for Calculating the Baum Reading of Condensed Ice Cream Mixes  

Microsoft Academic Search

The manufacture of ice cream mixes in the vacuum pan has created a need for a method for the accurate forecasting of the Baum6 hydrometer reading of these mixes, in order to prevent over or under condensation, and to provide a guide for indicating when the mix is ready to draw. This Baum6 reading has been and is still largely

R. A. Larson; P. S. Lucas



Termite Infestation Associated with Type of Soil in Pulau Pinang, Malaysia (Isoptera: Rhinotermitidae)  

PubMed Central

Nine soil samples from nine buildings infested with Coptotermes gestroi in Pulau Pinang, Malaysia, were tested for the type of soil texture. The soil texture analysis procedures used the hydrometer method. Four of nine buildings (44%) yielded loamy sand-type soil, whereas five of nine buildings (56%) contained sandy loam-type soil.

Majid, Abdul Hafiz Ab; Ahmad, Abu Hassan



Optical method for determining the state of charge of a lead-acid battery  

NASA Astrophysics Data System (ADS)

An optic device which utilizes the index of refraction and critical angle to determine the state of charge of a lead acid battery is discussed. The approach utilizes the change in the index of refraction of the battery acid vs. battery state of charge. The dynamic hydrometer is a float similar to the one used in a normal hydrometer whose position can be continuously monitored with a capacity sensor. The advantage is that the liquid level in the battery does not affect the reading, only the specific gravity is indicated. It is concluded that with the proper adjustment of angles, the instrument can be used for in situ monitoring of many chemical processes in which the index of refraction is used as an indicator.

Derouin, C. R.; Bobbett, R. E.; McCormick, J. B.; Kerwin, W. J.


SUNRAYCE 95: Working safely with lead-acid batteries and photovoltaic power systems  

SciTech Connect

This document is a power system and battery safety handbook for participants in the SUNRAYCE 95 solar powered electric vehicle program. The topics of the handbook include batteries, photovoltaic modules, safety equipment needed for working with sulfuric acid electrolyte and batteries, battery transport, accident response, battery recharging and ventilation, electrical risks on-board vehicle, external electrical risks, electrical risk management strategies, and general maintenance including troubleshooting, hydrometer check and voltmeter check.

DePhillips, M.P.; Moskowitz, P.D.; Fthenakis, V.M. [Brookhaven National Lab., Upton, NY (United States). Biomedical and Environmental Assessment Group



Abstracts of papers presented at the Eleventh International Laser Radar Conference  

NASA Technical Reports Server (NTRS)

Abstracts of 39 papers discuss measurements of properties from the Earth's ocean surface to the mesosphere, made with techniques ranging from elastic and inelastic scattering to Doppler shifts and differential absorption. Topics covered include: (1) middle atmospheric measurements; (2) meteorological parameters: temperature, density, humidity; (3) trace gases by Raman and DIAL techniques; (4) techniques and technology; (5) plume dispersion; (6) boundary layer dynamics; (7) wind measurements; visibility and aerosol properties; and (9) multiple scattering, clouds, and hydrometers.



Homogeneous Nucleation Rate for Highly Supercooled Cirrus Cloud Droplets  

Microsoft Academic Search

A mixed-phase hydrometer growth model has been applied to determining the nucleation mode and rate responsible for the glaciation of a highly supercooled liquid cloud studied jointly by ground-based polarization lidar and aircraft in situ probes. The cloud droplets were detected at the base of an orographically induced cirrus cloud at temperatures between 34.3 and 37.3C. The vertical distribution above

Kenneth Sassen; Gregory C. Dodd



SUNRAYCE 1995: Working safely with lead-acid batteries and photovoltaic power systems  

NASA Astrophysics Data System (ADS)

This document is a power system and battery safety handbook for participants in the SUNRAYCE 95 solar powered electric vehicle program. The topics of the handbook include batteries, photovoltaic modules, safety equipment needed for working with sulfuric acid electrolyte and batteries, battery transport, accident response, battery recharging and ventilation, electrical risks on-board vehicle, external electrical risks, electrical risk management strategies, and general maintenance including troubleshooting, hydrometer check and voltmeter check.

Dephillips, M. P.; Moskowitz, P. D.; Fthenakis, V. M.



A New Inversion-Based Algorithm for Retrieval of Over-Water Rain Rate from SSM/I Multichannel Imagery  

NASA Technical Reports Server (NTRS)

This paper discusses certain aspects of a new inversion based algorithm for the retrieval of rain rate over the open ocean from the special sensor microwave/imager (SSM/I) multichannel imagery. This algorithm takes a more detailed physical approach to the retrieval problem than previously discussed algorithms that perform explicit forward radiative transfer calculations based on detailed model hydrometer profiles and attempt to match the observations to the predicted brightness temperature.

Petty, Grant W.; Stettner, David R.



A Quality Control study of the distribution of NOAA MIRS Cloudy retrievals during Hurricane Sandy  

NASA Astrophysics Data System (ADS)

Cloudy radiance present a difficult challenge to data assimilation (DA) systems, through both the radiative transfer system as well the hydrometers required to resolve the cloud and precipitation. In most DA systems the hydrometers are not control variables due to many limitations. The National Oceanic and Atmospheric Administration's (NOAA) Microwave Integrated Retrieval System (MIRS) is producing products from the NPP-ATMS satellite where the scene is cloud and precipitation affected. The test case that we present here is the life time of Hurricane and then Superstorm Sandy in October 2012. As a quality control study we shall compare the retrieved water vapor content during the lifetime of Sandy with the first guess and the analysis from the NOAA Gridpoint Statistical Interpolation (GSI) system. The assessment involves the gross error check system against the first guess with different values for the observational error's variance to see if the difference is within three standard deviations. We shall also compare against the final analysis at the relevant cycles to see if the products which have been retrieved through a cloudy radiance are similar, given that the DA system does not assimilate cloudy radiances yet.

Fletcher, S. J.



Three-dimensional aspects of radiative transfer in remote sensing of precipitation: Application to the 1986 COHMEX storm  

NASA Technical Reports Server (NTRS)

Several multifrequency techniques for passive microwave estimation of precipitation based on the absorption and scattering properties of hydrometers have been proposed in the literature. In the present study, plane-parallel limitations are overcome by using a model based on the discrete-ordinates method to solve the radiative transfer equation in three-dimensional rectangular domains. This effectively accounts for the complexity and variety of radiation problems encountered in the atmosphere. This investigation presents result for plane-parallel and three-dimensional radiative transfer for a precipitating system, discusses differences between these results, and suggests possible explanations for these differences. Microphysical properties were obtained from the Colorado State University Regional Atmospehric Modeling System and represent a hailstorm observed during the 1986 Cooperative Huntsville Meteorological Experiment. These properties are used as input to a three-dimensional radiative transfer model in order to simulate satellite observation of the storm. The model output consists of upwelling brightness temperatures at several of the frequencies on the Special Sensor Microwave/Imager. The radiative transfer model accounts for scattering and emission of atmospheric gases and hydrometers in liquid and ice phases. Brightness temperatures obtained from the three-dimensional model of this investigation indicate that horizontal inhomogeneities give rise to brightness temperature fields that can be quite different from fields obtained using plane-parallel radiative transfer theory. These differences are examined for various resolutions of the satellite sensor field of view. In adddition, the issue of boundary conditions for three-dimensional atmospheric radiative transfer is addressed.

Haferman, J. L.; Krajewski, W. F.; Smith, T. F.



RAWS: The spaceborne radar wind sounder  

NASA Technical Reports Server (NTRS)

The concept of the Radar Wind Sounder (RAWS) is discussed. The goals of the RAWS is to estimate the following three qualities: the echo power, to determine rain rate and surface wind velocity; the mean Doppler frequency, to determine the wind velocity in hydrometers; and the spread of the Doppler frequency, to determine the turbulent spread of the wind velocity. Researchers made significant progress during the first year. The feasibility of the concept seems certain. Studies indicate that a reasonably sized system can measure in the presence of ice clouds and dense water clouds. No sensitivity problems exist in rainy environments. More research is needed on the application of the radar to the measurement of rain rates and winds at the sea surface.

Moore, Richard K.



An improved version of the extended velocity-azimuth display analysis of single-Doppler radar data  

NASA Astrophysics Data System (ADS)

Extended velocity-azimuth display (EVAD) analysis is useful for obtaining vertical profiles of horizontal divergence, vertical air velocity, vertical hydrometer velocity, and hydrometeor terminal fall speed in widespread precipitation. The technique uses a volume of velocity data collected with a single Doppler radar. Several improvements to the previously reported EVAD technique are discussed. They include the weighting of Fourier series coefficients to reflect their estimated error, a correction for heteroscedasticity (the systematic variation of residuals) in the regression analysis, and the weighting of data from different elevation angles to compensate for the finite thickness of the layers in which each analysis is performed. Vertical air velocity is obtained through a variational procedure. Procedures for dealiasing the velocity data and for rejecting outliers from the dataset are summarized. Recommendations for collecting radar data for use in EVAD analysis are made.

Matejka, Thomas; Srivastava, Ramesh C.



Ultrasonic dispersion of soils for routine particle size analysis: recommended procedures  

SciTech Connect

Ultrasonic techniques were found to be more effective than standard mechanical techniques to disperse soils for routine particle-size analysis (i.e., using a dispersing agent and mechanical mixing). Soil samples were tested using an ultrasonic homogenizer at various power outputs. The samples varied widely in texture and mineralogy, and included sands, silts, clays, volcanic soils, and soils high in organic matter. A combination of chemical and ultrasonic dispersion techniques were used in all tests. Hydrometer techniques were used for particle-size analysis. For most materials tested, clay percentage values indicated that ultrasonic dispersion was more complete than mechanical dispersion. Soils high in volcanic ash or iron oxides showed 10 to 20 wt % more clay when using ultrasonic mixing rather than mechanical mixing. The recommended procedure requires ultrasonic dispersion of a 20- to 40-g sample for 15 min at 300 W with a 1.9-cm-diameter ultrasonic homogenizer. 12 references, 5 figures, 1 table.

Heller, P.R.; Hayden, R.E.; Gee, G.W.



Wireless sensor node for surface seawater density measurements.  


An electronic meter to measure surface seawater density is presented. It is based on the measurement of the difference in displacements of a surface level probe and a weighted float, which according to Archimedes' law depends on the density of the water. The displacements are simultaneously measured using a high-accuracy magnetostrictive sensor, to which a custom electronic board provides a wireless connection and power supply so that it can become part of a wireless sensor network. The electronics are designed so that different kinds of wireless networks can be used, by simply changing the wireless module and the relevant firmware of the microcontroller. Lastly, laboratory and at-sea tests are presented and discussed in order to highlight the functionality and the performance of a prototype of the wireless density meter node in a Bluetooth radio network. The experimental results show a good agreement of the values of the calculated density compared to reference hydrometer readings. PMID:22736986

Baronti, Federico; Fantechi, Gabriele; Roncella, Roberto; Saletti, Roberto



Water Body Salinities II  

NSDL National Science Digital Library

In this activity, learners discuss the different salinities of oceans, rivers and estuaries. Learners then use experimentation to determine which sample is the best model of each type of natural water source. For the first test, learners make a hydrometer and use it to measure the density of the liquid samples. In the second test, learners freeze the water samples and examine them at certain time intervals to check degree of freezing, texture of the frozen samples, and other specifics that vary according to the amount of salt in the water. This activity can follow the Water Salinities I activity and/or be used in conjunction with the Estuaries activity, both of which can be found on SMILE.

Jersey, New; Center, Liberty S.; Coalition, New J.



Evaluation of quick tests for phosphorus determination in dairy manures.  


Nutrients in animal manure are valuable inputs in agronomic crop production. Rapid and timely information about manure nutrient content are needed to minimize the risks of phosphorus (P) over-application and losses of dissolved P (DP) in runoff from fields treated with manure. We evaluated the suitability of a commercial hand-held reflectometer, a hydrometer, and an electrical conductivity (EC) meter for determining DP and total P (TP) in dairy manures. Bulk samples (n = 107) collected from farms across CT, MD, NY, PA, and VA were highly variable in total solids (TS) concentration, ranging from 11 to 213gL(-1), in suspensions' pH (6.3-9.2), and EC (6.2-53.3 dS m(-1)). Manure DP concentrations measured using the RQFlex reflectometer (RQFlex-DP(s)) were related to molybdate-reactive P (MRP(s)) concentrations as follows: RQFlex-DP(s) = 0.471 x MRP(s) + 1102 (r2 = 0.29). Inclusion of pH and squared-pH terms improved the prediction of manure DP from RQFlex results (r2 = 0.66). Excluding five outlier samples that had pH < or = 6.9 the coefficient of determination (r2) for the MRP(s) and RQFlex-DP(s) relationship was 0.83 for 95% of the samples. Manure TS were related to hydrometer specific gravity readings (r2 = 0.53) that were in turn related to TP (r2 = 0.34), but not to either RQFlex-DP or MRP. Relationships between suspensions' EC and DP or TP were non-significant. Therefore, the RQFlex method is the only viable option for on-site quick estimates of DP that can be made more robust when complemented with TS and pH measurements. The DP quick test can provide near real-time information on soluble manure nutrient content across a wide range of handling and storage conditions on dairy farms and quick estimates of potential soluble P losses in runoff following land applications of manure. PMID:15701402

Lugo-Ospina, A; Dao, Thanh H; Van Kessel, J A; Reeves, J B



Total Lightning and Radar Storm Characteristics Associated with Severe Storms in Central Florida  

NASA Technical Reports Server (NTRS)

A number of prior studies have examined the association of lightning activity with the occurrence of severe weather and tornadoes, in particular. High flash rates are often observed in tornadic storms (Taylor, 1973; Johnson, 1980; Goodman and Knupp, 1993) but not always. Taylor found that 23% of nontornadic storms and 1% of non-severe storms had sferics rates comparable to the tornadic storms. MacGorman (1993) found that storms with mesocyclones produced more frequent intracloud (IC) lightning than cloud-to-ground (CG) lightning. MacGorman (1993) and others suggest that the lightning activity accompanying tomadic storms will be dominated by intracloud lightning-with an increase in intracloud and total flash rates as the updraft increases in depth, size, and velocity. In a recent study, Perez et al. (1998) found that CG flash rates alone are too variable to be a useful predictor of (F4, F5) tornado formation. Studies of non-tomadic storms have also shown that total lightning flash rates track the updraft, with rates increasing as the updraft intensities and decreasing rapidly with cessation of vertical growth or downburst onset (Goodman et al., 1988; Williams et al., 1989). Such relationships result from the development of mixed phase precipitation and increased hydrometer collisions that lead to the efficient separation of charge. Correlations between updraft strength and other variables such as cloud-top height, cloud water mass, and hail size have also been observed.

Goodman, Steven J.; Raghavan, Ravi; Ramachandran, Rahul; Buechler, Dennis; Hodanish, Stephen; Sharp, David; Williams, Earle; Boldi, Bob; Matlin, Anne; Weber, Mark



Permeability and compressibility of resedimented Gulf of Mexico mudrock  

NASA Astrophysics Data System (ADS)

We use a constant-rate-of strain consolidation test on resedimented Gulf of Mexico mudrock to determine the compression index (Cc) to be 0.618 and the expansion index (Ce) to be 0.083. We used crushed, homogenized Pliocene and Pleistocene mudrock extracted from cored wells in the Eugene Island block 330 oil field. This powdered material has a liquid limit (LL) of 87, a plastic limit (PL) of 24, and a plasticity index (PI) of 63. The particle size distribution from hydrometer analyses is approximately 65% clay-sized particles (<2 ?m) with the remainder being less than 70 microns in diameter. Resedimented specimens have been used to characterize the geotechnical and geophysical behavior of soils and mudstones independent of the variability of natural samples and without the effects of sampling disturbance. Previous investigations of resedimented offshore Gulf of Mexico sediments (e.g. Mazzei, 2008) have been limited in scope. This is the first test of the homogenized Eugene Island core material. These results will be compared to in situ measurements to determine the controls on consolidation over large stress ranges.

Betts, W. S.; Flemings, P. B.; Schneider, J.



Development of the millimeter-wave complex, intended for environmental control of nuclear, chemical, and power production facilities  

NASA Astrophysics Data System (ADS)

The paper is concerned with the development of the millimeter wave complex, intended for environmental control. To organize a reliable system for control and monitoring of the atmosphere one needs an adequate set of the measurement methods and devices for carrying out the needed measurements. At best, the devices must be capable of the remote sensing of the atmosphere in the continuous mode and should have proper means for communication with the central data acquisition system. The most informative methods for the atmospheric measurements are based on the microwave remote sensing. Particularly, using a 5-millimeter receiver (radiometer) it is possible to measure temperature vs. height dependence up to 1 km with required for temperature and height resolutions. Besides, a 3-millimeter coherent radar can be used for measuring the amount of condensed water (fog, rain, clouds) and smoke. Such hydrometers and other small particles support a dissipation of pollution from the accident to the distant areas. Besides, the radar allows us to measure the speed and direction of wind, which is very important for prediction of the danger for the other areas. So, the microwave complex, consisting of a 5-mm radiometer and a 3-mm coherent radar enables us to obtain needed information about the atmosphere state and to predict situation after the accident took place.

Kosov, A. S.; Vald-Perlov, V. M.; Strukov, I. A.



Quartz resonator state-of-charge monitor for lead-acid batteries  

NASA Astrophysics Data System (ADS)

We have demonstrated that a thickness shear mode quartz resonator can be used as a real-time, in situ monitor of the state-of-charge of lead-acid batteries. The resonator is sensitive to changes in the density and viscosity of the sulfuric acid electrolyte. Both of these liquid parameters vary monotonically with the battery state-of-charge. This new monitor is more precise than sampling hydrometers, and since it is compatible with the corrosive electrolyte environment, it can be used for in situ monitoring. A TSM resonator consists of gold electrodes deposited on opposite surfaces of a thin AT-cut quartz crystal. When an RF voltage is applied to the electrodes, a shear strain is introduced in the piezoelectric quartz and mechanical resonance occurs between the surfaces. A liquid in contact with one of the quartz surfaces is viscously entrained, which perturbs the resonant frequency and resonance magnitude. If the surface is smooth, the changes in both frequency and magnitude are proportional to (rho(eta))(exp (1/2)), where rho is the liquid density and eta is the viscosity.

Cernosek, R. W.; Martin, S. J.; Wessendorf, K. O.; Rumpf, A. N.


A numerical modeling study of a Montana thunderstorm: 1. Model results versus observations involving nonelectrical aspects  

NASA Astrophysics Data System (ADS)

A recently developed Storm Electrification Model (SEM) has been used to simulate the July 19, 1981, Cooperative Convective Precipitation Experiment (CCOPE) case study cloud. This part of the investigation examines the comparison between the model results and the observations of the actual cloud with respect to its nonelectrical aspects. A timing equivalence is established between the simulation and observations based on an explosive growth phase which was both observed and modeled. This timing equivalence is used as a basis upon which the comparisons are made. The model appears to do a good job of reproducing (in both space and time) many of the observed characteristics of the cloud. These include: (1) the general cloud appearance; (2) cloud size; (3) cloud top rise rate; (4) rapid growth phase; (5) updraft structure; (6) first graupel appearance; (7) first radar echo; (8) qualitative radar range-height indicator evolution; (9) cloud decay; and (10) the location of hydrometers with respect to the updraft/-downdraft structure. Some features that are not accurately modeled are the cloud base height, the maximum liquid water content, and the time from first formation of precipitation until it reaches the ground. While the simulation is not perfect, the faithfulness of the model results to the observations is sufficient to give us confidence that the microphysical processes active in this storm are adequately represented in the model physics. Areas where model improvement is indicated are also discussed.

Helsdon, John H.; Farley, Richard D.



QA/QC requirements for physical properties sampling and analysis  

SciTech Connect

This report presents results of an assessment of the available information concerning US Environmental Protection Agency (EPA) quality assurance/quality control (QA/QC) requirements and guidance applicable to sampling, handling, and analyzing physical parameter samples at Comprehensive Environmental Restoration, Compensation, and Liability Act (CERCLA) investigation sites. Geotechnical testing laboratories measure the following physical properties of soil and sediment samples collected during CERCLA remedial investigations (RI) at the Hanford Site: moisture content, grain size by sieve, grain size by hydrometer, specific gravity, bulk density/porosity, saturated hydraulic conductivity, moisture retention, unsaturated hydraulic conductivity, and permeability of rocks by flowing air. Geotechnical testing laboratories also measure the following chemical parameters of soil and sediment samples collected during Hanford Site CERCLA RI: calcium carbonate and saturated column leach testing. Physical parameter data are used for (1) characterization of vadose and saturated zone geology and hydrogeology, (2) selection of monitoring well screen sizes, (3) to support modeling and analysis of the vadose and saturated zones, and (4) for engineering design. The objectives of this report are to determine the QA/QC levels accepted in the EPA Region 10 for the sampling, handling, and analysis of soil samples for physical parameters during CERCLA RI.

Innis, B.E.



Development of advanced cloud parameterizations to examine air quality, cloud properties, and cloud-radiation feedback in mesoscale models  

SciTech Connect

The distribution of atmospheric pollutants is governed by dynamic processes that create the general conditions for transport and mixing, by microphysical processes that control the evolution of aerosol and cloud particles, and by chemical processes that transform chemical species and form aerosols. Pollutants emitted into the air can undergo homogeneous gas reactions to create a suitable environment for the production by heterogeneous nucleation of embryos composed of a few molecules. The physicochemical properties of preexisting aerosols interact with newly produced embryos to evolve by heteromolecular diffusion and coagulation. Hygroscopic particles wig serve as effective cloud condensation nuclei (CCN), while hydrophobic particles will serve as effective ice-forming nuclei. Clouds form initially by condensation of water vapor on CCN and evolve in a vapor-liquid-solid system by deposition, sublimation, freezing, melting, coagulation, and breakup. Gases and aerosols that enter the clouds undergo aqueous chemical processes and may acidity hydrometer particles. Calculations for solar and longwave radiation fluxes depend on how the respective spectra are modified by absorbers such as H{sub 2}O, CO{sub 2}, O{sub 3}, CH{sub 4}, N{sub 2}O, chlorofruorocarbons, and aerosols. However, the flux calculations are more complicated for cloudy skies, because the cloud optical properties are not well defined. In this paper, key processes such as tropospheric chemistry, cloud microphysics parameterizations, and radiation schemes are reviewed in terms of physicochemical processes occurring, and recommendations are made for the development of advanced modules applicable to mesoscale models.

Lee, In Young



Factors associated with colostral specific gravity in dairy cows.  


The objectives of this study were to identify factors associated with colostral specific gravity in dairy cows, as measured by a commercially available hydrometer (Colostrometer). Colostral specific gravity was measured in 1085 first-milking colostrum samples from 608 dairy cows of four breeds on a single farm during a 5-yr period. Effects of breed, lactation number, and month and year of calving on colostral specific gravity were determined, as were correlations between colostral specific gravity, nonlactating period length, and 305-d yields of milk, protein, and fat. For 75 multiparous Holstein cows, relationships between colostral specific gravity, colostral IgG1, protein, and fat concentrations, and season of calving were determined. Colostral specific gravity values were lower for Brown Swiss and Ayrshire cows than for Jersey and Holstein cows, and lower for cows entering first or second lactation than third or later lactations. Month of calving markedly affected colostral specific gravity values, with highest values occurring in autumn and lowest values in summer. In multiparous Holstein cows, colostral specific gravity was more strongly correlated with colostral protein concentration (r = 0.76) than IgG1 concentration (r = 0.53), and colostral protein concentration varied seasonally (higher in autumn than summer). Our results demonstrate that colostral specific gravity more closely reflects colostral protein concentration than IgG1 concentration and is markedly influenced by month of calving. These results highlight potential limitations of using colostral specific gravity as an indicator of IgG1 concentration. PMID:11352170

Morin, D E; Constable, P D; Maunsell, F P; McCoy, G C



Evaluating regional cloud-permitting simulations of the WRF model for the Tropical Warm Pool International Cloud Experiment (TWP-ICE, Darwin 2006)  

SciTech Connect

Data from the Tropical Warm Pool I5 nternational Cloud Experiment (TWPICE) were used to evaluate two suites of high-resolution (4-7 km, convection-resolving) simulations of the Advanced Research Weather Research and Forecasting (WRF) model with a focus on the performance of different cloud microphysics (MP) schemes. The major difference between these two suites of simulations is with and without the reinitializing process. Whenreinitialized every three days, the four cloud MP schemes evaluated can capture the general profiles of cloud fraction, temperature, water vapor, winds, and cloud liquid and ice water content (LWC and IWC, respectively). However, compared with surface measurements of radiative and moisture fluxes and satellite retrieval of top-of-the-atmosphere (TOA) fluxes, disagreements do exist. Large discrepancies with observed LWC and IWC and derived radiative heating profiles can be attributed to both the limitations of the cloud property retrievals and model performance. The simulated precipitation also shows a wide range of uncertainty as compared with observations, which could be caused by the cloud MP schemes, complexity of land-sea configuration, and the high temporal and spatial variability. In general, our result indicates the importance of large-scale initial and lateral boundary conditions in re-producing basic features of cloudiness and its vertical structures. Based on our case study, we find overall the six-hydrometer single-moment MP scheme(WSM6) [Hong and Lim, 2006] in the WRF model si25 mulates the best agree- ment with the TWPICE observational analysis.

Wang, Yi; Long, Charles N.; Leung, Lai-Yung R.; Dudhia, Jimy; McFarlane, Sally A.; Mather, James H.; Ghan, Steven J.; Liu, Xiaodong



Quantifying Sediment Transport in a Premontane Transitional Cloud Forest  

NASA Astrophysics Data System (ADS)

Quantifying sediment transport is a difficult task in any watershed, and relatively little direct measurement has occurred in tropical, mountainous watersheds. The Howler Monkey Watershed (2.2 hectares) is located in a premontane transitional cloud forest in San Isidro de Peas Blancas, Costa Rica. In June 2012, a V-notch stream-gaging weir was built in the catchment with a 8 ft by 6 ft by 4 ft concrete stilling basin. Sediment captured by the weir was left untouched for an 11 month time period. To collect the contents of the weir, the stream was rerouted and the weir was drained. The stilling basin contents were systematically sampled, and samples were taken to a lab and characterized using sieve and hydrometer tests. The wet volume of the remaining sediment was obtained, and dry mass was estimated. Particle size distribution of samples were obtained from lab tests, with 96% of sediment trapped by the weir being sand or coarser. The efficiency of the weir as a sediment collector was evaluated by comparing particle fall velocities to residence time of water in the weir under baseflow conditions. Under these assumptions, only two to three percent of the total mass of soil transported in the stream is thought to have been suspended in the water and lost over the V-notch. Data were compared to the Universal Soil Loss Equation (USLE), a widely accepted method for predicting soil loss in agricultural watersheds. As expected, application of the USLE to a tropical rainforest was problematic with uncertainty in parameters yielding a soil loss estimate varying by a factor of 50. Continued monitoring of sediment transport should yield data for improved methods of soil loss estimation applicable to tropical mountainous forests.

Waring, E. R.; Brumbelow, J. K.



Glacier Mass Balance measurements in Bhutan  

NASA Astrophysics Data System (ADS)

Long-term glacier measurements are scarce in the Himalayas, partly due to lack of resources as well as inaccessibility of most of the glaciers. There are over 600 glaciers in Bhutan in the Eastern Himalayas, but no long-term measurements. However, such studies are an important component of hydrological modelling, and especially relevant to the proposed expansion of hydropower resources in this area. Glaciological studies are also critical to understanding the risk of jkulhlaups or GLOFS (glacier lake outburst floods) from glaciers in this region. Glacier mass balance measurements have been initiated on a glacier in the Chamkhar Chu region in central Bhutan by the Department of Hydro-Met Services in co-operation with the Norwegian Water Resources and Energy Directorate. Chamkhar Chu is the site of two proposed hydropower plants that will each generate over 700 MW, although the present and future hydrological regimes in this basin, and especially the contribution from glaciers, are not well-understood at present. There are about 94 glaciers in the Chamkhar Chhu basin and total glacier area is about 75 sq. km. The glaciers are relatively accessible for the Himalayas, most of them can be reached after only 4-5 days walk from the nearest road. One of the largest, Thana glacier, has been chosen as a mass balance glacier and measurements were initiated in 2013. The glacier area is almost 5 sq. km. and the elevation range is 500 m (5071 m a.s.l. to 5725 m a.s.l.) making it suitable as a benchmark glacier. Preliminary measurements on a smaller, nearby glacier that was visited in 2012 and 2013 showed 1 m of firn loss (about 0.6 m w.eq.) over 12 months.

Jackson, Miriam; Tenzin, Sangay; Tashi, Tshering



The first one year measurements at the Monte Portella (Italy) climate high altitude station  

NASA Astrophysics Data System (ADS)

With the purpose of contributing in providing information about atmospheric composition baseline variability in the Mediterranean basin, an atmospheric station has been installed at a high mountain site in Central Italy (Monte Portella, 2401 m a.s.l.), on July 20th 2012. Monte Portella is not far from the Corno Grande (the highest peak of the Italian Appennines, 2912 m a.s.l.) and the Calderone, the southernmost glacier in Europe. This remote site is very interesting for the analysis of the atmospheric processes occurring in the free troposphere of the Mediterranean Basin since local emissions are not in its proximity; moreover, Cristofanelli et al. (2013) found that during the July 2009 the air masses reaching the site originate mainly from the Mediterranean basin, but also from the Continental Europe and from the Northern Italy and that different origins of the air masses impact differently on the ozone budget. This station is part of the SHARE (Station at High Altitude for Environmental Research) Project. The instrumentation until now available includes: a meteorological station (VAISALA Hydromet for measurements of Temperature, Pressure, Relative Humidity, Wind speed and direction, Solar Radiation and precipitation), ozone monitor (2B technologies, model 205), NO monitor (2B technologies, model 410), aerosol size distribution (OPC monitor multichannel, FAI instruments. In our study we will show the results of the first one year of continuous measurements collected. In particular, we will study the ozone trend as a function of meteorological parameter and, in detail, of the wind direction. We will show also the PM1 and PM10 annual trends individuating events of pollution transport in free troposphere and analyzing their dependence on different air masses origins. These analyses represent the first hints about atmospheric composition variability at high altitude in the central Italy. Reference Cristofanelli, P., Di Carlo, P., D'Altorio, A., Dari Salisburgo, C., Tuccella, P., Biancofiore, F., Stocchi, P., Verza, G.P., Landi, T.C., Marinoni, A., Calzolari, F., Duchi, R., and Bonasoni, P., Analysis of summer Ozone observations at a high mountain site in central Italy, Pure Appl. Geophys., DOI 10.1007/s00024-012-0630-1, 2013.

Aruffo, Eleonora; Di Carlo, Piero; D'Altorio, Alfonso; Busilacchio, Marcella; Biancofiore, Fabio; Giammaria, Franco; Del Grande, Francesco; Bonasoni, Paolo; Cristofanelli, Paolo; Vuillermoz, Elisa



Principles and practical implementation for high resolution multi-sensor QPE  

NASA Astrophysics Data System (ADS)

The multi-sensor Quantitative Precipitation Estimation (MPE) is a principle and a practical concept and is becoming a well-known term in the scientific circles of hydrology and atmospheric science. The main challenge in QPE is that precipitation is a highly variable quantity with extensive spatial and temporal variability at multiple scales. There are MPE products produced from satellites, radars, models and ground sensors. There are MPE products at global scale (Heinemann et al. 2002), continental scale (Seo et al. 2010; Zhang et al. 2011) and regional scale (Kitzmiller et al. 2011). Lots of the MPE products are used to alleviate the problems of one type of sensor by another. Some multi-sensor products are used to move across scales. This paper looks at a comprehensive view of the "concept of multi sensor precipitation estimate", from different perspectives. This paper delineates the MPE problem into three categories namely, a) Scale based MPE, b) MPE for accuracy enhancement and coverage and c) Integrative across scales. For example, by introducing dual polarization radar data to the MPE system, QPE can be improved significantly. In last decade, dual polarization radars are becoming an important tool for QPE in operational networks. Dual polarization radars offer an advantage to interpret more accurate physical models by providing information of the size, shape, phase and orientation of hydrometers (Bringi and Chandrasekar 2001). In addition, these systems have the ability to provide measurements that are immune to absolute radar calibration and partial beam blockage as well as help in data quality enhancement. By integrating these characteristics of dual polarization radar, QPE performance can be improved in comparison of single polarization radar based QPE (Cifelli and Chandrasekar 2010). Dual-polarization techniques have been applied to S and C band radar systems for several decades and higher frequency system such as X band are now widely available to the radar community. One solution to the dilemma of precipitation variability across scales can be to supplement existing long-range radar networks with short-range higher frequency systems (X band). The smaller X band systems provide more portability and higher data resolution, and networks of these systems may be a cost-effective option for improved rainfall estimation for radar networks with large separation distances (McLaughlin et al. 2009). This paper will describe the principles of the MPE concept and implementation issues of within the context of the classification described above.

Chandra, C. V.; Lim, S.; Cifelli, R.



Rip current monitoring using GPS buoy system  

NASA Astrophysics Data System (ADS)

The occurrence of rip current in the Haeundae beach, which is one of the most famous beaches in South Korea, has been threatening beach-goers security in summer season annually. Many coastal scientists have been investigating rip currents by using field observations and measurements, laboratory measurements and wave tank experiments, and computer and numerical modeling. Rip current velocity is intermittent and may rapidly increase within minutes due to larger incoming wave groups or nearshore circulation instabilities. It is important to understand that changes in rip current velocity occur in response to changes in incoming wave height and period as well as changes in water level. GPS buoys have been used to acquire sea level change data, atmospheric parameters and other oceanic variables in sea for the purposes of vertical datum determination, tide correction, radar altimeter calibration, ocean environment and marine pollution monitoring. Therefore, we adopted GPS buoy system for an experiment which is to investigate rip current velocity; it is sporadic and may quickly upsurge within minutes due to larger arriving wave groups or nearshore flow uncertainties. In this study, for high accurate positioning of buy equipment, a Satellite Based Argumentation System DGPS data logger was deployed to investigate within floating object, and it can be acquired three-dimensional coordinate or geodetic position of buoy with continuous NMEA-0183 protocol during 24 hours. The wave height measured by in-situ hydrometer in a cross-shore array clearly increased before and after occurrence of rip current, and wave period also was lengthened around an event. These results show that wave height and period correlate reasonably well with long-shore current interaction in the Haeundae beach. Additionally, current meter data and GPS buoy data showed that rip current velocities, about 0.2 m/s, may become dangerously strong under specific conditions. Acknowledgement This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology(2010-0024670)

Song, DongSeob; Kim, InHo; Kang, DongSoo



Development of a database-driven system for simulating water temperature in the lower Yakima River main stem, Washington, for various climate scenarios  

USGS Publications Warehouse

A model for simulating daily maximum and mean water temperatures was developed by linking two existing models: one developed by the U.S. Geological Survey and one developed by the Bureau of Reclamation. The study area included the lower Yakima River main stem between the Roza Dam and West Richland, Washington. To automate execution of the labor-intensive models, a database-driven model automation program was developed to decrease operation costs, to reduce user error, and to provide the capability to perform simulations quickly for multiple management and climate change scenarios. Microsoft SQL Server 2008 R2 Integration Services packages were developed to (1) integrate climate, flow, and stream geometry data from diverse sources (such as weather stations, a hydrologic model, and field measurements) into a single relational database; (2) programmatically generate heavily formatted model input files; (3) iteratively run water temperature simulations; (4) process simulation results for export to other models; and (5) create a database-driven infrastructure that facilitated experimentation with a variety of scenarios, node permutations, weather data, and hydrologic conditions while minimizing costs of running the model with various model configurations. As a proof-of-concept exercise, water temperatures were simulated for a "Current Conditions" scenario, where local weather data from 1980 through 2005 were used as input, and for "Plus 1" and "Plus 2" climate warming scenarios, where the average annual air temperatures used in the Current Conditions scenario were increased by 1degree Celsius (C) and by 2C, respectively. Average monthly mean daily water temperatures simulated for the Current Conditions scenario were compared to measured values at the Bureau of Reclamation Hydromet gage at Kiona, Washington, for 2002-05. Differences ranged between 1.9 and 1.1C for February, March, May, and June, and were less than 0.8C for the remaining months of the year. The difference between current conditions and measured monthly values for the two warmest months (July and August) were 0.5C and 0.2C, respectively. The model predicted that water temperature generally becomes less sensitive to air temperature increases as the distance from the mouth of the river decreases. As a consequence, the difference between climate warming scenarios also decreased. The pattern of decreasing sensitivity is most pronounced from August to October. Interactive graphing tools were developed to explore the relative sensitivity of average monthly and mean daily water temperature to increases in air temperature for model output locations along the lower Yakima River main stem.

Voss, Frank; Maule, Alec



Carbon exchange variability over Amazon Basin using coupledhydrometeorological-mixed layer PBL-carbon dioxide assimilation modeling system forced by satellite-derived surface radiation and precipitation  

NASA Astrophysics Data System (ADS)

A hydrometeorological model is modified to include a simple slab model of the mixed layer for the estimation of CO2 fluxes in Amazonia. Three carbon assimilation models are examined for use in the FSU hydromet model, of which the NCAR LSM module is chosen because respiration rates are provided and CO2, latent and sensible heat fluxes are coupled through stomatal resistance. Initial calculations of NEP show a necessity for modeling canopy-boundary layer interactions to reproduce observed morning effluxes at forest tower sites at Manaus and Jaru. CO2 concentrations in five layers in and above the canopy are modeled with associated fluxes. Sensible heat fluxes are consistently overestimated until canopy heat capacity is taken into account. Estimations of canopy heat storage are found using observed differences between net incoming radiation and latent and sensible heat fluxes, or observed total residual energy. Calibration of fluxes at three tower sites is conducted using modeled total residual energy at the forest sites and modified photosynthesis parameters at the pasture site. The forcing parameters of downwelling solar radiation (K ?) and temperature are found to exert the most influence over modeled CO2 fluxes at the tower sites. Model application over the basin shows that while vegetation type is the primary factor controlling CO2 fluxes area-wide, K ? is the primary forcing variable that produces spatial and temporal variability of CO2 fluxes. Modeled CO2 fluxes show mean monthly uptake values in the range of 1-3 mumol m-2 s-1 and diurnal progressions of large coherent areas of CO2 effluxes over the forest, progressing from SE to NW in December, and from NE to SW in June. Inspection of area-wide modeled fluxes near tower sites shows that the use of ECMWF winds and temperatures creates a spurious nocturnal stability that produces much larger morning efflux magnitudes than observations suggest. Comparison of CO2 fluxes at nearly 20,000 forest points within Amazonia with overall forest mean values using eight months of model output suggest that flux observations from five strategically placed towers used in conjunction with existing towers at Manaus and Jaru would be sufficient to reproduce representative area-wide CO 2 flux variability.

Grose, Andrew


Flood forecasting for the Ukrainian part of the Tisza Basin: linking with the numerical weather forecasts, comparative testing of distributed and lumped models  

NASA Astrophysics Data System (ADS)

The implementation of new flood forecasting systems for the Ukrainian part of the Tisza basin has started last years by the customisation of Mike-11 model for the Uzh River and Latoritsa River (part of the Bodrog Catchment) in the frame of the joint project with the 'DHI Water&Environment'. The calibration and testing of the lumped parameter model NAM was provided in collaboration with the Ukrainian Hydrometcenter and the Uzhgorod Hydrometcenter for the period 1998-2000, which includes two hazardous floods of years 1998 and 2000. The tuning of hydrodynamical module of Mike-11 is provided in collaboration with the Transcarpathian Branch of State Committee of Water Management (SCWM), Uzhgorod. The information about existing and designed hydraulic structures in the river channels, -bridges, polders, dikes, pump stations is used for the model tuning. The flood forecasting system for Uzh River and Latoritsa River based on Mike -11 is in pre-operational use in Uzhgorod Hydromet and SCUWM offices. The advance time of the flood forecasts can be increased by the real-time assimilation of the precipitation forecasts of a Numerical Weather Predictions (NWP) model. The Penn State University /UCAR NWP model MM5 was customized for the Ukrainian territory in resolution 30*30 km on the basis of the rare gridded forecasting data from the German meteorological center Offenbach, assimilating the data from the Ukrainian meteorological stations, processed by the Ukrainian Hydrometcenter. The region of the Uzh and Latoritsa watersheds was simulated by MM5 in the resolution 10*10 km for the linking with the Mike -11 (NAM). The preliminary results of flood forecasting on the basis of the meteorological forecasts are analyzed. For further improvement of the flood forecasting systems the implementations of GIS based distributed models are planned. Two types of distributed models based upon physically meaningful parameters are comparatively studied- 2-D finite- difference model RUNTOX (Kivva, Zheleznyak, 2001) based on Saint Venant equations and TOPographic Kinematic Approximation and Integration - TOPKAPI model (Todini, 1995,2000). The new computer code was developed, based on the TOPKAPI equations. Both models was initially tested for the small watersheds ( from 0.085 km2 to 0.40 km2 ) of the Boguslav Field Experimental Laboratory of the Ukrainian Hydrometeorological Institute. The comparison with the experimental data shows that TOPKAPI produces the reasonable results for the different floods without special tuning of the model parameters. The study of the applicability of TOPKAPI for the sub-watersheds of Uzh and Latoritsa rivers is going on.

Belov, S.; Donchytz, G.; Kivva, S.; Kuschan, A.; Zheleznyak, M.



An Observationally-Based Evaluation of Cloud Ice and Liquid Water in CMIP3 and CMIP5 GCMs and Contemporary Reanalyses Using Contemporary Satellite Data (Invited)  

NASA Astrophysics Data System (ADS)

Representing clouds and cloud climate feedbacks in global climate models (GCMs) remains a pressing challenge to reduce and quantify uncertainties associated with climate change projection. Vertical structures of clouds simulated by present-day models have not been extensively examined using vertically-resolved cloud hydrometers such as cloud ice water (CIW) content and cloud liquid water (CLW) content. The gap in available observations for cloud mass was clearly evident from the wide disparity in the CIW path [Waliser et al., 2009] and CLW path [Li et al., 2008;2011] values exhibited in the CMIP3 GCMs. We present an observationally-based evaluation of the CIW and CLW of present-day GCMs, notably 20th century CMIP5 simulations, and compare these results to the CMIP3 and two recent reanalyses (ECMWF and MERRA). We use three different CloudSat+CALIPSO CIW products as well as three different observation CLW products, CloudSat, MODIS and AMSRE and their combined product for CLW with methods to remove the contribution from the convective core ice mass and/or precipitating cloud hydrometeors with variable sizes and falling speeds so that a robust observational estimate with uncertainty can be obtained for model evaluations. Note, considering the CloudSat's limitations of CLW retrievals due to contamination from the precipitation and from radar clutter near the surface, an alternative CLW is synergistically constructed using MODIS CLW and CloudSat CLW. The results show that for annual mean CIW path, there are factors of 2-10 in the differences between observations and models for a majority of the GCMs and for a number of regions. Based on a number of metrics, the ensemble behavior of CMIP5 has improved considerably relative to CMIP3 (~ 50%), although neither the CMIP5 ensemble mean nor any individual model performs particularly well, and there are still a number of models that exhibit very large biases despite the availability of relevant observations. For CLW, most of the CMIP3/CMIP5 annual mean CLW path values are overestimated by factors of 2-10 compared to observations globally. For the vertical structure of CIW/CLW content, significant systematic biases are found with many models biased significantly. Based on the Taylor diagram, the ensemble performance of CMIP5 CLW path simulation shows little or no improvement relative to CMIP3. The implications of these results on model representations of the earth radiation balance are discussed, along with caveats and uncertainties associated with the observational estimates, model and observation representations of the precipitating and cloudy ice components, relevant physical processes and parameterizations.

Li, J. F.; Waliser, D. E.; Chen, W.; Deng, M.; Lebsock, M. D.; Stephens, G. L.; Guan, B.; Christensen, M.; Teixeira, J.



Observations to support adaptation: Principles, scales and decision-making  

NASA Astrophysics Data System (ADS)

As has been long noted, a comprehensive, coordinated observing system is the backbone of any Earth information system. Demands are increasingly placed on earth observation and prediction systems and attendant services to address the needs of economically and environmentally vulnerable sectors and investments, including energy, water, human health, transportation, agriculture, fisheries, tourism, biodiversity, and national security. Climate services include building capacity to interpret information and recognize standards and limitations of data in the promotion of social and economic development in a changing climate. This includes improving the understanding of climate in the context of a variety of temporal and spatial scales (including the influence of decadal scale forcings and land surface feedbacks on seasonal forecast reliability). Climate data and information are central for developing decision options that are sensitive to climate-related uncertainties and the design of flexible adaptation pathways. Ideally monitoring should be action oriented to support climate risk assessment and adaptation including informing robust decision making to multiple risks over the long term. Based on the experience of global observations programs and empirical research we outline- Challenges in developing effective monitoring and climate information systems to support adaptation. The types of observations of critical importance needed for sector planning to enhance food, water and energy security, and to improve early warning for disaster risk reduction Observations needed for ecosystem-based adaptation including the identification of thresholds, maintenance of biological diversity and land degradation The benefits and limits of linking regional model output to local observations including analogs and verification for adaptation planning To support these goals a robust systems of integrated observations are needed to characterize the uncertainty surrounding emergent risks including overcoming unrealistically precise information demands. While monitoring systems design and operation should be guided by the standards and requirements of management, those who provide information to the system (e.g. hydromet services) should also derive benefits. Drawing on identified information needs to support climate risk management (in drought, water resources and other areas) we outline principles of effective monitoring and develop preliminary strategic guidance for information systems being developed through the GEO, GCOS and Global and national frameworks for climate services. The efficacy of such services are improved by a problem-solving orientation, participatory planning, extension management and improvements in the use and value of existing data to legitimize new investments.

Pulwarty, R. S.



Deep convection in the tropical area: Hector a case study using TRMM data and high resolution model simulation.  

NASA Astrophysics Data System (ADS)

The tropics are one of the most important regions for the exchange and transport of water vapor and chemical species from the upper troposphere to the lower stratosphere; changes in emissions of chemicals at the ground or how quickly they are carried aloft could cause the chemistry of the stratosphere to change and as a consequence the net radiative balance. The tropical storms are one of the main devices for this type of interaction. In Australia, the tropical thunderstorms have different possible sources; in particular the development of equatorial events is related to convergence zones typical of the ITCZ (Intertropical Convergence Zone). One of the deepest convective systems of the globe is the tropical thunderstorm Hector that develops almost daily in the Tiwi Islands, near Darwin city (tropical northern Australia), during the pre-monsoon period and break monsoon. The thunderstorm Hector has been observed to reach to altitudes of 20 km and thus potentially in the lower stratosphere, so it represents one of processes for exchange between the troposphere and the stratosphere. Hector is the topics of numerous campaigns because of difficulties in its predictability: during the SCOUT-O3 project (Stratosphere-Climate Links with emphasis on the Upper Troposphere and Lower Stratosphere), a campaign was held on Tiwi Islands to the purposes of improving the understanding of the interaction between convection and the tropical tropopause layer. In the framework of this UE project a study of Hector tropical thunderstorm is performed to the aim of evaluating the vertical transport. The triggering factor together with the microphysical structure of this deep tropical cyclone has been investigated using MM5V3 and the new model WRF with data from the TRMM Precipitation Radar and from TRMM Microwave Imager. A comparison between the hydrometers retrieved by the TRMM Precipitation Radar (PR) and the one detected by the TRMM Microwave Imager (TMI) has been carried out. The model results confirm previous studies concerning Hector classification (type A or type B), and the associated vertical velocities. On the other hand the comparison with TRMM data allows for assessing a good agreement for both the amount and the vertical distribution of hydrometeors between model and observations. Eventually, the goodness of the vertical distribution of the hydrometeors would support the hypothesis of a correct estimation of Hector updrafts.

Gentile, Sabrina; Ferretti, Rossella; Silvio Marzano, Frank



On the measure of large woody debris in an alpine catchment  

NASA Astrophysics Data System (ADS)

The management of large woody debris (LWD) in Alpine torrents is a complex and ambiguous task. On one side the presence of LWD contributes to in-channel and floodplain morphological processes and plays an important role in landscape ecology and biodiversity. On the other side LWD increases considerably flood hazards when some river cross-sections result critical for the human interface (e.g. culverts, bridges, artificial channels). Only few studies provide quantitative data of LWD volumes in Alpine torrents. Research is needed both at basin scale processes (LWD recruiting from hillslopes) and at channel scale processes (feeding from river bank, storage/transport/deposition of LWD along the river bed). Our study proposes an integrate field survey methodology to assess the overall LWD amount which can be entrained by a flood. This knowledge is mandatory for the scientific research, for the implementation of LWD transport models, and for a complete hazard management in mountain basins. The study site is the high-relief basin of the Cordevole torrent (Belluno Province, Central Alps, Italy) whose outlet is located at the Saviner village (basin area of 109 square kilometers). In the November 1966 an extreme flood event occurred and some torrent reaches were heavily congested by LWD enhancing the overall damages due to long-duration overflows. Currently, the LWD recruitment seems to be strictly correlated with bank erosion and hillslope instability and the conditions of forest stand suggest LWD hazard is still high. Previous studies on sub-catchments of the Cordevole torrent have also shown an inverse relation between the drainage area and the LWD storage in the river-bed. Present contribution analyzes and quantifies the presence of LWD in the main valley channel of the Cordevole basin. A new sampling methodology was applied to integrate surveys of riparian vegetation and LWD storage. Data inventory confirms the previous relationship between LWD volumes and drainage area and indicates the floating as primary origin of LWD presence in the river bed. The total amount of LWD at the basin outlet resulted 1300 cubic meters corresponding to about 12 cubic meters per square kilometer of drainage area. Additional data about in-channel dynamics and threshold discharges to move LWD are in progress. These will be obtained through an innovative monitoring approach based on active transponders (RFID, Radio Frequency Identification). 70 transponder have been inserted in selected LWD samples and 70 transponders will be inserted in standardized artificial LWD to carry out experiments during the snowmelt season. A fixed antenna is located at the outlet section on a check-dam together with a video-camera and a hydrometer. The overall arrangement of the LWD monitoring system under test is then presented.

D'Agostino, V.; Bertoldi, G.; Rigon, E.



Climate related natural hazards management in the vulnerable regions of Uzbekistan - experiences in the frame of projects Climate Risk Management in Uzbekistan (CRM-Uz) and Water in Central Asia (CAWa)  

NASA Astrophysics Data System (ADS)

Increased frequency of natural hazards under conditions of observed climate change in Uzbekistan has become challenging concern and shows the need to develop more effective climate risk mechanisms towards improving the security of society and sustainable development. In the framework of presented study, the importance of drought monitoring and methodologies for early warning for such purposes in Uzbekistan are demonstrated. For the conditions of Uzbekistan, droughts are most dangerous climate related natural phenomenon. Therefore, the CRM-Uz Project on Climate Risk Management was established with focus on reducing climate risks, strengthening adaptive capacity for stimulating the development of early warning mechanisms, as well as to build up the basis for long-term investments. This serves to increase resilience to climate impacts in the country. In the frame of the CRM-Uz Project, Drought Early Warning System (DEWS), has been developed and implemented in one of the southern provinces of Uzbekistan (Kashkadarya). The main task of DEWS is to provide population with information on the possibility of upcoming drought season in advance. DEWS is used for the assessment, monitoring, prevention, early warning and decision making in this region. Such early warning system provides the required information to undertake appropriate measures against drought and to mitigate its adverse effects to society. It is clear that during years with expected drought the hydrological forecasts become much more important. Complex mathematical model which simulates of run-off formation as a basis of DEWS provides the seasonal hydrological forecasts that are used to inform all concerned sectors, especially the agricultural sector on water availability during the vegetation period. In the frame of cooperation with German Research Centre for Geosciences (GFZ) within the CAWa Project, the DEWS was extended through implementation of MODSNOW - the operational tool for snow cover monitoring at the Drought Monitoring Centre at UzHydromet. The upgrade of the DEWS withMODSNOW strengthens DEWS's capacity in terms of improvement the hydrological forecasting. Moreover, based on climate scenarios provided within the CAWa project by the University of Wrzburg, the regional hydrological model AISHF was used to asses medium and long term water availability in the Kashkadarya River which indicates a reduction of water resources in the selected basin in the future.

Merkushkin, Alexander; Gafurov, Abror; Agaltseva, Natalya; Pak, Alexander; Mannig, Birgit; Paeth, Heiko; Vorogushyn, Sergiy; Unger-Shayesteh, Katy



A granulometry and secondary mineral fingerprint of chemical weathering in periglacial landscapes and its application to blockfield origins  

NASA Astrophysics Data System (ADS)

A review of published literature was undertaken to determine if there was a fingerprint of chemical weathering in regoliths subjected to periglacial conditions during their formation. If present, this fingerprint would be applied to the question of when blockfields in periglacial landscapes were initiated. These blocky diamicts are usually considered to represent remnants of regoliths that were chemically weathered under a warm, Neogene climate and therefore indicate surfaces that have undergone only a few metres to a few 10s of metres of erosion during the Quaternary. Based on a comparison of clay and silt abundances and secondary mineral assemblages from blockfields, other regoliths in periglacial settings, and regoliths from non-periglacial settings, a fingerprint of chemical weathering in periglacial landscapes was identified. A mobile regolith origin under, at least seasonal, periglacial conditions is indicated where clay(%) ? 0.5*silt(%) + 8 across a sample batch. This contrasts with a mobile regolith origin under non-periglacial conditions, which is indicated where clay(%) ? 0.5*silt(%) - 6 across a sample batch with clay(%) ? 0.5*silt(%) + 8 in at least one sample. A range of secondary minerals, which frequently includes interstratified minerals and indicates high local variability in leaching conditions, is also commonly present in regoliths exposed to periglacial conditions during their formation. Clay/silt ratios display a threshold response to temperature, related to the freezing point of water, but there is little response to precipitation or regolith residence time. Lithology controls clay and silt abundances, which increase from felsic, through intermediate, to mafic compositions, but does not control clay/silt ratios. Use of a sedigraph or Coulter Counter to determine regolith granulometry systematically indicates lower clay abundances and intra-site variability than use of a pipette or hydrometer. In contrast to clay/silt ratios, secondary mineral assemblages vary according to regolith residence time, temperature, and/or precipitation. A microsystems model is invoked as a conceptual framework in which to interpret the concurrent formation of the observed secondary mineral ranges. According to the fingerprint of chemical weathering in periglacial landscapes, there is generally no evidence of blockfield origins under warm Neogene climates. Nearly all blockfields appear to be a product of Quaternary physical and chemical weathering. A more dominant role for periglacial processes in further bevelling elevated, low relief, non-glacial surface remnants in otherwise glacially eroded landscapes is therefore indicated.

Goodfellow, Bradley W.



A search for model parsimony in a real time flood forecasting system  

NASA Astrophysics Data System (ADS)

As regards the hydrological simulation of flood events, a physically based distributed approach is the most appealing one, especially in those areas where the spatial variability of the soil hydraulic properties as well as of the meteorological forcing cannot be left apart, such as in mountainous regions. On the other hand, dealing with real time flood forecasting systems, less detailed models requiring a minor number of parameters may be more convenient, reducing both the computational costs and the calibration uncertainty. In fact in this case a precise quantification of the entire hydrograph pattern is not necessary, while the expected output of a real time flood forecasting system is just an estimate of the peak discharge, the time to peak and in some cases the flood volume. In this perspective a parsimonious model has to be found in order to increase the efficiency of the system. A suitable case study was identified in the northern Apennines: the Taro river is a right tributary to the Po river and drains about 2000 km2 of mountains, hills and floodplain, equally distributed . The hydrometeorological monitoring of this medium sized watershed is managed by ARPA Emilia Romagna through a dense network of uptodate gauges (about 30 rain gauges and 10 hydrometers). Detailed maps of the surface elevation, land use and soil texture characteristics are also available. Five flood events were recorded by the new monitoring network in the years 2003-2007: during these events the peak discharge was higher than 1000 m3/s, which is actually quite a high value when compared to the mean discharge rate of about 30 m3/s. The rainfall spatial patterns of such storms were analyzed in previous works by means of geostatistical tools and a typical semivariogram was defined, with the aim of establishing a typical storm structure leading to flood events in the Taro river. The available information was implemented into a distributed flood event model with a spatial resolution of 90m; then the hydrologic detail was reduced by progressively assuming a uniform rainfall field and constant soil properties. A semi-distributed model, obtained by subdividing the catchment into three sub-catchment, and a lumped model were also applied to simulate the selected flood events. Errors were quantified in terms of the peak discharge ratio, the flood volume and the time to peak by comparing the simulated hydrographs to the observed ones.

Grossi, G.; Balistrocchi, M.



Precipitation from the GPM Microwave Imager and Constellation Radiometers  

NASA Astrophysics Data System (ADS)

Satellite precipitation retrievals from microwave sensors are fundamentally underconstrained requiring either implicit or explicit a-priori information to constrain solutions. The radiometer algorithm designed for the GPM core and constellation satellites makes this a-priori information explicit in the form of a database of possible rain structures from the GPM core satellite and a Bayesian retrieval scheme. The a-priori database will eventually come from the GPM core satellite's combined radar/radiometer retrieval algorithm. That product is physically constrained to ensure radiometric consistency between the radars and radiometers and is thus ideally suited to create the a-priori databases for all radiometers in the GPM constellation. Until a robust product exists, however, the a-priori databases are being generated from the combination of existing sources over land and oceans. Over oceans, the Day-1 GPM radiometer algorithm uses the TRMM PR/TMI physically derived hydrometer profiles that are available from the tropics through sea surface temperatures of approximately 285K. For colder sea surface temperatures, the existing profiles are used with lower hydrometeor layers removed to correspond to colder conditions. While not ideal, the results appear to be reasonable placeholders until the full GPM database can be constructed. It is more difficult to construct physically consistent profiles over land due to ambiguities in surface emissivities as well as details of the ice scattering that dominates brightness temperature signatures over land. Over land, the a-priori databases have therefore been constructed by matching satellite overpasses to surface radar data derived from the WSR-88 network over the continental United States through the National Mosaic and Multi-Sensor QPE (NMQ) initiative. Databases are generated as a function of land type (4 categories of increasing vegetation cover as well as 4 categories of increasing snow depth), land surface temperature and total precipitable water. One year of coincident observations, generating 20 and 80 million database entries, depending upon the sensor, are used in the retrieval algorithm. The remaining areas such as sea ice and high latitude coastal zones are filled with a combination of CloudSat and AMSR-E plus MHS observations together with a model to create the equivalent databases for other radiometers in the constellation. The most noteworthy result from the Day-1 algorithm is the quality of the land products when compared to existing products. Unlike previous versions of land algorithms that depended upon complex screening routines to decide if pixels were precipitating or not, the current scheme is free of conditional rain statements and appears to produce rain rate with much greater fidelity than previous schemes. There results will be shown.

Kummerow, Christian; Randel, David; Kirstetter, Pierre-Emmanuel; Kulie, Mark; Wang, Nai-Yu



BOOK REVIEW: Practical Density Measurement and Hydrometry  

NASA Astrophysics Data System (ADS)

Density determinations are very important not only for science and production but also in everyday life, since very often a product is sold by mass but the content of the package is measured by volume (or vice versa) so that the density is needed to convert the values. In production processes the density serves as a measure of mixing ratios and other properties. In science, the determination of Avogadro's constant using silicon single crystals and the potential replacement of the kilogram prototype boost density determination to an extremely low relative uncertainty of 10-7 or less. The book by S V Gupta explains in detail the foundations of any density measurement, namely the volume determination of solid artefacts in terms of the SI base unit of length and the density of water and mercury. Both the history and the actual state of science are reported. For practical density measurements, these chapters contain very useful formulae and tables. Water is treated in detail since it is most widely used as a standard not only for density determination but also to gravimetrically calibrate the capacity of volumetric glassware. Two thirds of the book are devoted to the practical density measurement of solids and liquids, mainly using classical instruments like pycnometers and hydrometers. Methods using free flotation of samples in a liquid without suspension are especially useful for small samples. Also, density determinations of powders and granular or porous samples are explained. Unfortunately, modern density meters of the oscillation type are dealt with in only a few pages. The book is clearly written and easy to understand. It contains a lot of evaluations of formulae that for practical measurements are represented in detailed tables. Methods and measurement procedures are described in detail, including also the calculation of uncertainty. Listings of the advantages and disadvantages of the different methods are very helpful. S V Gupta has written a book that will be a great help for scientists, students and practitioners. The book fills a gap since there is no modern book that describes density measurements and hydrometry in such detail. Horst Bettin

Gupta, S. V.