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  • 1
    Electronic Resource
    Electronic Resource
    SYNTHESIS OF FLOW-DURATION CURVES FOR UNREGULATED STREAMS IN NEW HAMPSHIRE (1978)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 14 (1978), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : Flow-duration curves are concise pictures of flow variability at a point on a stream, and provide essential information for all water-resource planning. In New Hampshire, useful estimates of flow-duration curves for ungaged points on unregulated streams can be made using only information readily available from contour maps: 1) area of the basin above the point of interest; and 2) either the measured mean basin elevation or the elevations of the highest and lowest points in the basin. Measured or estimated mean basin elevation is then used in regression equations to estimate mean flow QC and the flow exceeded 95% of the time, Q95. QC is assumed to occur at the 27% exceedance frequency. Q02, Q05, and Q30 are estimated as multiples of QC. Equations are provided for calculating 95% confidence intervals for future estimates using the method. The dependence of mean flow on elevation is due to positive vertical precipitation gradients and negative vertical evapotranspiration gradients. The dependence of Q95 on elevation appears to be due largely to the fact that it rains more often, that snowmelt takes longer, and that evapotranspiration is reduced at higher elevations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1978.tb02298.x
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  • 2
    Electronic Resource
    Electronic Resource
    DISCUSSION (1978)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 14 (1978), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1978.tb05596.x
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  • 3
    Electronic Resource
    Electronic Resource
    NEW ENGLAND DROUGHT AND RELATIONS WITH LARGE SCALE ATMOSPHERIC CIRCULATION PATTERNS (2002)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 38 (2002), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : To provide a basis for regional hydroclimatic forecasting, New England (NE) precipitation and streamflow are compared with indices for the El Niño/Southern Oscillation, the Pacific North American (PNA) pattern, and the North Atlantic Oscillation (NAO). Significant positive correlations are found between the NAO index and monthly streamflow at western inland locations, with the strongest seasonal correlations occurring in winter. Smoothed records for the winter NAO and winter streamflow are highly correlated at some sites, suggesting that interrelationships are most significant in the low frequency spectrum. However, correlations between the NAO and precipitation are not significant, so further examination of other factors is needed to explain the relationship between the NAO and streamflow. NAO related regional air temperature, sea surface temperature (SST), storm tracking, and snowfall variability are possible mechanisms for the observed teleconnection. Exceptionally cool regional air temperatures, and SSTs, and unique regional storm track patterns characterized NE's climate during the famous 1960s drought, suggesting that concurrent (persistent) negative NAO conditions may have contributed to the severity of that event. Monthly and winter averaged regional streamflow variability are also significantly correlated with the PNA index. This, along with results from previous studies, suggests that tropospheric wave character and associated North Pacific SST anomalies are also related to NE regional drought conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.2002.tb04348.x
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  • 4
    Electronic Resource
    Electronic Resource
    COMPARISON OF MODELS FOR ESTIMATING FLOOD QUANTILES IN NEW HAMPSHIRE AND VERMONT (1999)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 35 (1999), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: We develop and compare three regression models for estimating flood quantiles at ungaged stream reaches in New Hampshire and Vermont. These models emerge from systematic analysis and validation of relations between flood magnitude and six candidate predictors reflecting basin size, topography, and climate and channel size at 36 gaging stations with record lengths exceeding 20 years. Of the candidate predictors, bank full width is most highly correlated with flood magnitude and the best prediction equation is based on width. Thus channel geometry is closely related to the current hydrologic regime in spite of geologically recent glaciation and apparently non-alluvial bank materials. We also develop models that use information obtainable from maps or GIS. The best of these uses drainage area and drainage-basin elevation as predictors, but it is substantially less precise than the width-based relation. A third relation using only drainage area as a predictor is even less precise but may be useful for some purposes. No other single predictors or combinations yielded useful predictions, although some had been included in previously-established models for the region. Model comparison included examination of residuals generated by regression using one-at-a-time suppression of data points and comparison with precision obtainable with gaging records of varying lengths.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1999.tb04210.x
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  • 5
    Electronic Resource
    Electronic Resource
    ESTIMATING LOW-FLOW QUANTILES FROM DRAINAGE-BASIN CHARACTERISTICS IN NEW HAMPSHIRE AND VERMONT (1995)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 31 (1995), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : This study systematically develops, validates, and compares alternative approaches for estimating quantiles of the distribution of annual minimum seven-day-average flows (7Q) for ungaged, unregulated drainage basins in New Hampshire and Vermont via regression on map-measurable drainage-basin characteristics. At 47 gaging stations in the region, the hypotheses that 7Q is log normally distributed and serially independent are not rejected, and the regional average spatial correlation is R= 0.35. Step-forward examination of a suite of potential predictor variables revealed that logarithm of drainage area, mean elevation, and fraction of basin covered with sand and gravel deposits are significant predictors of quantiles of 7Q. The regression equations were incorporated into four approaches to estimate the 7Q value with a nonexceedence probability of 0.1, 7Q10. Comparison of observed values and values predicted via a delete-one jackknife resampling validation indicates that one of the approaches gives estimates with acceptable bias and precision, with median relative error of 33 percent and prediction error of 64 percent. This is equivalent to the precision obtainable with only one to two years of gaging records. In spite of this limited precision, the approaches developed herein are useful for predicting 7Q quantiles at ungaged sites. Further improvement in precision will likely be possible only by exploiting the spatial correlation of annual 7Q.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1995.tb03377.x
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  • 6
    Electronic Resource
    Electronic Resource
    APPLICATION OF KRIGING TO ESTIMATING MEAN ANNUAL PRECIPITATION IN A REGION OF OROGRAPHIC INFLUENCE (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 24 (1988), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : Estimates of mean annual precipitation (MAP) over areas are the starting point for all computations of water and chemical balances for drainage basins and surface water bodies. Any errors in the estimates of MAP are propagated through the balance computations. These errors can be due to: (1) failures of individual gages to collect the amount of precpitation that actually falls; (2) operator errors; and (3) failure of the raingage network to adequately sample the region of interest. This paper attempts to evaluate the last of these types of error by applying kriging in two different approaches to estimating MAP in New Hampshire and Vermont, USA. The data base is the 1951–1980 normal precipitation at 120 raingages in the two states and in adjacent portions of bordering states and provinces. In the first approach, kriging is applied directly to the MAP values, while in the second, kriging is applied to a “precipitation delivery factor” that represents the MAP with the orographic effect removed. The first approach gives slightly better kriged estimates of MAP at seven validation stations that were not included in the original analysis, but results in an error surface that is highly contorted and in larger maximum errors over most of the region. The second approach had a considerably smoother error surface and, thus, is generally preferable as a basis for point and areal estimates of MAP. MAP estimates in the region have 95 percent confidence intervals of about 20 cm/yr at low and moderate elevations, and up to 35 cm/yr at high elevations. These uncertainties amount to about 20 percent of estimated MAP values.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1988.tb02991.x
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  • 7
    Electronic Resource
    Electronic Resource
    PLANNING LEVEL ESTIMATES OF THE VALUE OF RESERVOIRS FOR WATER SUPPLY AND FLOW AUGMENTATION IN NEW HAMPSHIRE (1981)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of the American Water Resources Association 17 (1981), S. 0 
    Details
    ISSN: 1752-1688
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: : In general, the choice among reservoirs for water supply or flow augmentation is a multiobjective problem. Choices are based in part on the yield available from water supply reservoirs or, in the case of flow augmentation reservoirs, on the increase in low flows at downstream locations. Detailed estimates of these effects may be too costly for basin planning purposes. Thus this paper presents methods for rapid estimation of those quantities for New Hampshire. For water supply reservoirs, a composite empirical relation between Y95 (the draft available 95 percent of the time) and storage ratio, S*, is developed from previous studies in the region. For flow augmentation reservoirs, empirical relations between S* and degree of regulation, R*, are applied to each upstream regulating reservoir. Values of regulation arc then summed and divided by the mean flow at the downstream reach of interest. This parameter, (ΓR)*, is then related to increase in flow available 95 percent of the time by an empirical relation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1752-1688.1981.tb01277.x
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  • 8
    Electronic Resource
    Electronic Resource
    Sharp Interface Models of Salt Water Intrusion and Wellhead Delineation on Nantucket Island, Massachusetts (1998)
    Oxford, UK : Blackwell Publishing Ltd
    Ground water 36 (1998), S. 0 
    Details
    ISSN: 1745-6584
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Notes: Inferred increases in 1981 to 1997 pumping records suggest that by the year 2020, the majority of Nantucket Island municipal wellfields will be pumping near or at capacity. A sharp-interface model is used in this study to assess the impact of projected increases in pumping from the Wyers Valley and proposed State Forest municipal wellfields on Nantucket Island, Massachusetts. The model was first calibrated as part of a sensitivity study using a nine-year record of monthly water level data from a monitoring well network and salinity data from a deep borehole completed near the island's center. Best-fit values of hydraulic conductivity and specific storage obtained in the sensitivity analysis are in good agreement with those measured by single and multiple well aquifer tests across the island.The calibrated model was used to assess hydrologic conditions across the island between 1997 and 2020 due to projected increases in municipal wellfield pumping. Transient simulation results suggest that salt water will invade the well screen of the deep (32 m) Wyers Valley production well by the year 2014. Further, the width of the fresh water/salt water mixing zone under the municipal wellfields will triple by 2020 due to increasing seasonal fluctuations in pumping required to accommodate summer tourism. Using published estimates of 2020 municipal wellfield pumping, wellhead delineation zones were also calculated using a variety of assumptions regarding the island's fresh water lens geometry (uniform, variable thickness with no upconing; variable thickness with upconing). Results indicate that the calculated delineation zones are most sensitive to island geometry and, to a lesser extent, to the fresh water lens thickness.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1745-6584.1998.tb02190.x
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  • 9
    Electronic Resource
    Electronic Resource
    Altered Calcium Homeostasis in Adults with Cystic Fibrosis (1999)
    Springer
    Osteoporosis international 10 (1999), S. 102-108 
    Details
    ISSN: 1433-2965
    Keywords: Key words:Calcium – Cystic fibrosis – Malabsorption – Osteoporosis – Vitamin D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract: Bone mineral density (BMD) in cystic fibrosis (CF) patients falls progressively below normal with advancing age, in part due to steroid administration, low levels of sex hormones, chronic inflammatory disease, physical inactivity, and chronic malabsorption of calcium and/or vitamin D. The purpose of this study was to compare the fractional absorption of 45Ca and urinary excretion of calcium in CF subjects and normal controls following a high-calcium breakfast containing 45Ca. Seven young men and 5 young women with CF with pancreatic insufficiency were studied on two separate occasions, with and without administration of pancreatic enzymes. Eleven healthy young adults with normal BMD measurements served as controls. Mean T-scores at the lumbar spine and femur were significantly lower in the CF subjects (p〈0.002). Following baseline, fasting collections, timed serum and urine samples were obtained for 5 h after the meal. Fractional absorption (FA) of 45Ca was estimated by the method of Marshall and Nordin. At baseline, CF subjects had lower mean serum 25-hydroxyvitamin D, calcium and albumin values (p〈0.03 for each), slightly, but not significantly (p= 0.12), lower albumin-corrected calcium values, equivalent serum 1,25-dihydroxyvitamin D values and a trend toward a higher mean serum parathyroid hormone (PTH) value (p= 0.10). Without pancreatic enzymes, CF subjects showed significantly impaired calcium absorption (5 h FA: 11.8 ± 0.5 for controls vs 8.9 ± 0.2 for CF subjects, p= 0.02) and excretion (4 h excretion: 0.20 ± 0.08 mg Ca/mg creatinine for controls vs 0.16 ± 0.09 mg Ca/mg for CF subjects, p= 0.025). Addition of pancreatic enzymes did not fully compensate for this deficiency. In addition, CF patients had higher serum PTH values after a high-calcium meal (p= 0.03), suggesting mild secondary hyperparathyroidism. Altered calcium homeostasis is likely to be a factor in the development of bone disease in CF patients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001980050202
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