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Larry Benson - One of the best experts on this subject based on the ideXlab platform.
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Influence of the Pacific decadal oscillation on the climate of the Sierra Nevada, California and Nevada
Quaternary Research, 2020Co-Authors: Larry Benson, Steve P. Lund, Braddock K. Linsley, Joe Smoot, Scott A. Mensing, Scott Stine, Andre Sarna-wojcickiAbstract:Mono Lake sediments have recorded five major oscillations in the Hydrologic Balance between A.D. 1700 and 1941. These oscillations can be correlated with tree-ring-based oscillations in Sierra Nevada snowpack. Comparison of a tree-ring-based reconstruction of the Pacific Decadal Oscillation (PDO) index (D’Arrigo et al., 2001) with a coral-based reconstruction of Subtropical South Pacific sea-surface temperature (Linsley et al., 2000) indicates a high degree of correlation between the two records during the past 300 yr. This suggests that the PDO has been a pan-Pacific phenomena for at least the past few hundred years. Major oscillations in the Hydrologic Balance of the Sierra Nevada correspond to changes in the sign of the PDO with extreme droughts occurring during PDO maxima. Four droughts centered on A.D. 1710, 1770, 1850, and 1930 indicate PDO-related drought reoccurrence intervals ranging from 60 to 80 yr.
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hibal a Hydrologic isotopic Balance model for application to paleolake systems
Quaternary Science Reviews, 2002Co-Authors: Larry Benson, Fred PailletAbstract:A simple Hydrologic-isotopic-Balance (HIBAL) model for application to paleolake d 18 O records is presented. Inputs to the model include discharge, on-lake precipitation, evaporation, and the d 18 O values of these fluidfluxes. Monthly values of climatic parameters that govern the fractionation of 18 O and 16 O during evaporation have been extracted from historical data sets and held constant in the model. The ability of the model to simulate changes in the Hydrologic Balance and the d 18 O evolution of the mixed layer has been demonstrated using measured data from Pyramid Lake, Nevada. Simulations of the response in d 18 O to step- and periodic-function changes in fluid inputs indicate that the Hydrologic Balance and d 18 O values lag climate change. Input of reconstructedriver d ischarges andtheir d 18 O values to PyramidandWalker lakes ind icates that minima andmaxima in simulated d 18 O records correspond to minima and maxima in the reconstructed volume records and that the overall shape of the volume and d 18 O records is similar. The model was also used in a simulation of abrupt oscillations in the d 18 O values of paleo-Owens Lake,
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Stable isotopes of oxygen and hydrogen in the Truckee River–Pyramid Lake surface‐water system. 2. A predictive model of δ18O and 182H in Pyramid Lake
Limnology and Oceanography, 1994Co-Authors: Steve W. Hostetler, Larry BensonAbstract:A physically based model of variations in WO and 6*H in Pyramid Lake is presented. For inputs, the model uses measurements of liquid water inflows and outflows and their associated isotopic compositions and a set of meteorological data (radiative fluxes, air temperature, relative humidity, and windspced). The model simulates change of lake volume, thermal and isotopic stratification, evaporation, and the isotopic composition of evaporation. A validation of the model for 1987-1989 and 199 1 indicates that it can reproduce measured intra- and interannual variations of 6’*0 and 6*H. Three applications of the model demonstrate its ability to simulate longer term responses of VO to change in the Hydrologic Balance and Hydrologic characteristics (opening and closing) of the lake. Annual variations of the isotopic (al80 and a2H) composition of Pyramid Lake are associated by Benson (1994) with annual patterns of precipitation, evaporation, streamflow discharge, and lake mixing (stratification). Larger, long-term changes in isotopic composition are linked to change in the Hydrologic Balance and the Hydrologic state (e.g. whether the lake is open or closed) of the lake. In this paper, we present a model used to simulate variations in 6180 and 62H in Pyramid Lake that occur in response to change in the Hydrologic Balance and climate. Several steady state and dynamic models of al80 and 62H have been developed and applied
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Stable isotopes of oxygen and hydrogen in the Truckee River‐Pyramid Lake surface‐water system. 3. Source of water vapor overlying Pyramid Lake
Limnology and Oceanography, 1994Co-Authors: Larry Benson, James W. C. WhiteAbstract:During 1988 and 1989, a series of water-vapor extractions were conducted in the Pyramid Lake basin to determine the source of moisture that overlies the lake. Calculations of the isotopic and water-vapor Balances were made from isotopic and meteorological data from the Pyramid Lake and Reno, Nevada, areas. The results indicate that in the warm season, most of the moisture that overlies the lake is derived from evaporation as opposed to advected moisture. Isotopic fluxes at the lake surface can be approximated by climatic data from the lake site, which simplifies the calculation of this input in numerical simulations of the isotopic evolution of the lake. The stable-isotopic composition of a lake is a function of the volume-weighted isotopic values of each component of the lake’s Hydrologic Balance. Researchers have used the stable-isotope history of a lake together with the volume-weighted isotopic composition of easily measured components of the Hydrologic Balance to estimate the stable-isotope values or amounts of less easily measured components of the Hydrologic Balance (see IAEA 1970, 1979). It is usually relatively simple to quantify the amounts and isotopic compositions of components of the surface-water system and the isotopic composition of groundwater. It is often more difficult to quantify the amount and direction of groundwater transport across the sediment-water interface and the amount and isotopic composition of lake surface evaporation. The isotopic value of water evaporated from a lake is highly dependent on the isotopic value Acknowledgments We express our appreciation to those who assisted in sampling, including Jim Davis, Dan Mosley, and Nancy Vucinich. Special thanks to Irving Friedman, who loaned us the copper traps used for water-vapor extraction; to Carol Kendall and Tyler Coplen, who oversaw the isotopic analyses; to James Ashby, who maintained the weather stations; and to Steve Hostetler, who extracted the meteorological data from the weather-station database and stratified the wind data for the Sutcliffc and Northshore sites. We also thank Zell Peterman, Steve Hostetler, and Pieter Tans for reviews of earlier versions of this manuscript.
Stephen S. Howe - One of the best experts on this subject based on the ideXlab platform.
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Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Journal of Paleolimnology, 2006Co-Authors: Fasong Yuan, Braddock K. Linsley, Stephen S. HoweAbstract:Walker Lake, a Hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860. A high-resolution multi-proxy sediment core record from Walker Lake has been generated through analysis of total inorganic carbon (TIC), total organic carbon (TOC), and oxygen and carbon isotope ratios (δ^18O and δ^13 C) of both downcore bulk TIC and ostracods over the last 200 yr. This allows us to examine how these sediment indices respond to actual changes in this lake’s Hydrologic Balance at interannual to decadal timescales. In Walker Lake sediments, changes in %TIC, %TOC, and δ^13C and δ^18O of TIC and ostracods are all associated to varying degrees with changes in the lake’s Hydrologic Balance, with δ^18O of the TIC fraction (δ^18O_TIC) being the most highly correlated and the most effective Hydrologic indicator in this closed-basin lake. The δ^18O_TIC record from Walker Lake nearly parallels the instrumental lake-level record back to 1860. However, comparison with sporadic lake-water δ^18O and dissolved inorganic carbon δ^13C (δ^13C_DIC) results spanning the last several decades suggests that the isotopic values of downcore carbonate sediments may not be readily translated into absolute or even relative values of corresponding lake-water δ^18O and δ^13C_DIC. Changes in the lake’s Hydrologic Balance usually lead to changes in isotopic composition of lake waters and downcore sediments, but not all the variations in downcore isotopic composition are necessarily caused by Hydrologic changes.
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Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Journal of Paleolimnology, 2006Co-Authors: Fasong Yuan, Braddock K. Linsley, Stephen S. HoweAbstract:Walker Lake, a Hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860. A high-resolution multi-proxy sediment core record from Walker Lake has been generated through analysis of total inorganic carbon (TIC), total organic carbon (TOC), and oxygen and carbon isotope ratios (δ18O and δ13 C) of both downcore bulk TIC and ostracods over the last 200 yr. This allows us to examine how these sediment indices respond to actual changes in this lake’s Hydrologic Balance at interannual to decadal timescales. In Walker Lake sediments, changes in %TIC, %TOC, and δ13C and δ18O of TIC and ostracods are all associated to varying degrees with changes in the lake’s Hydrologic Balance, with δ18O of the TIC fraction (δ18OTIC) being the most highly correlated and the most effective Hydrologic indicator in this closed-basin lake. The δ18OTIC record from Walker Lake nearly parallels the instrumental lake-level record back to 1860. However, comparison with sporadic lake-water δ18O and dissolved inorganic carbon δ13C (δ13CDIC) results spanning the last several decades suggests that the isotopic values of downcore carbonate sediments may not be readily translated into absolute or even relative values of corresponding lake-water δ18O and δ13CDIC. Changes in the lake’s Hydrologic Balance usually lead to changes in isotopic composition of lake waters and downcore sediments, but not all the variations in downcore isotopic composition are necessarily caused by Hydrologic changes.
Fasong Yuan - One of the best experts on this subject based on the ideXlab platform.
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Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Journal of Paleolimnology, 2006Co-Authors: Fasong Yuan, Braddock K. Linsley, Stephen S. HoweAbstract:Walker Lake, a Hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860. A high-resolution multi-proxy sediment core record from Walker Lake has been generated through analysis of total inorganic carbon (TIC), total organic carbon (TOC), and oxygen and carbon isotope ratios (δ^18O and δ^13 C) of both downcore bulk TIC and ostracods over the last 200 yr. This allows us to examine how these sediment indices respond to actual changes in this lake’s Hydrologic Balance at interannual to decadal timescales. In Walker Lake sediments, changes in %TIC, %TOC, and δ^13C and δ^18O of TIC and ostracods are all associated to varying degrees with changes in the lake’s Hydrologic Balance, with δ^18O of the TIC fraction (δ^18O_TIC) being the most highly correlated and the most effective Hydrologic indicator in this closed-basin lake. The δ^18O_TIC record from Walker Lake nearly parallels the instrumental lake-level record back to 1860. However, comparison with sporadic lake-water δ^18O and dissolved inorganic carbon δ^13C (δ^13C_DIC) results spanning the last several decades suggests that the isotopic values of downcore carbonate sediments may not be readily translated into absolute or even relative values of corresponding lake-water δ^18O and δ^13C_DIC. Changes in the lake’s Hydrologic Balance usually lead to changes in isotopic composition of lake waters and downcore sediments, but not all the variations in downcore isotopic composition are necessarily caused by Hydrologic changes.
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Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Journal of Paleolimnology, 2006Co-Authors: Fasong Yuan, Braddock K. Linsley, Stephen S. HoweAbstract:Walker Lake, a Hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860. A high-resolution multi-proxy sediment core record from Walker Lake has been generated through analysis of total inorganic carbon (TIC), total organic carbon (TOC), and oxygen and carbon isotope ratios (δ18O and δ13 C) of both downcore bulk TIC and ostracods over the last 200 yr. This allows us to examine how these sediment indices respond to actual changes in this lake’s Hydrologic Balance at interannual to decadal timescales. In Walker Lake sediments, changes in %TIC, %TOC, and δ13C and δ18O of TIC and ostracods are all associated to varying degrees with changes in the lake’s Hydrologic Balance, with δ18O of the TIC fraction (δ18OTIC) being the most highly correlated and the most effective Hydrologic indicator in this closed-basin lake. The δ18OTIC record from Walker Lake nearly parallels the instrumental lake-level record back to 1860. However, comparison with sporadic lake-water δ18O and dissolved inorganic carbon δ13C (δ13CDIC) results spanning the last several decades suggests that the isotopic values of downcore carbonate sediments may not be readily translated into absolute or even relative values of corresponding lake-water δ18O and δ13CDIC. Changes in the lake’s Hydrologic Balance usually lead to changes in isotopic composition of lake waters and downcore sediments, but not all the variations in downcore isotopic composition are necessarily caused by Hydrologic changes.
Braddock K. Linsley - One of the best experts on this subject based on the ideXlab platform.
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Influence of the Pacific decadal oscillation on the climate of the Sierra Nevada, California and Nevada
Quaternary Research, 2020Co-Authors: Larry Benson, Steve P. Lund, Braddock K. Linsley, Joe Smoot, Scott A. Mensing, Scott Stine, Andre Sarna-wojcickiAbstract:Mono Lake sediments have recorded five major oscillations in the Hydrologic Balance between A.D. 1700 and 1941. These oscillations can be correlated with tree-ring-based oscillations in Sierra Nevada snowpack. Comparison of a tree-ring-based reconstruction of the Pacific Decadal Oscillation (PDO) index (D’Arrigo et al., 2001) with a coral-based reconstruction of Subtropical South Pacific sea-surface temperature (Linsley et al., 2000) indicates a high degree of correlation between the two records during the past 300 yr. This suggests that the PDO has been a pan-Pacific phenomena for at least the past few hundred years. Major oscillations in the Hydrologic Balance of the Sierra Nevada correspond to changes in the sign of the PDO with extreme droughts occurring during PDO maxima. Four droughts centered on A.D. 1710, 1770, 1850, and 1930 indicate PDO-related drought reoccurrence intervals ranging from 60 to 80 yr.
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Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Journal of Paleolimnology, 2006Co-Authors: Fasong Yuan, Braddock K. Linsley, Stephen S. HoweAbstract:Walker Lake, a Hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860. A high-resolution multi-proxy sediment core record from Walker Lake has been generated through analysis of total inorganic carbon (TIC), total organic carbon (TOC), and oxygen and carbon isotope ratios (δ^18O and δ^13 C) of both downcore bulk TIC and ostracods over the last 200 yr. This allows us to examine how these sediment indices respond to actual changes in this lake’s Hydrologic Balance at interannual to decadal timescales. In Walker Lake sediments, changes in %TIC, %TOC, and δ^13C and δ^18O of TIC and ostracods are all associated to varying degrees with changes in the lake’s Hydrologic Balance, with δ^18O of the TIC fraction (δ^18O_TIC) being the most highly correlated and the most effective Hydrologic indicator in this closed-basin lake. The δ^18O_TIC record from Walker Lake nearly parallels the instrumental lake-level record back to 1860. However, comparison with sporadic lake-water δ^18O and dissolved inorganic carbon δ^13C (δ^13C_DIC) results spanning the last several decades suggests that the isotopic values of downcore carbonate sediments may not be readily translated into absolute or even relative values of corresponding lake-water δ^18O and δ^13C_DIC. Changes in the lake’s Hydrologic Balance usually lead to changes in isotopic composition of lake waters and downcore sediments, but not all the variations in downcore isotopic composition are necessarily caused by Hydrologic changes.
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Evaluating sedimentary geochemical lake-level tracers in Walker Lake, Nevada, over the last 200 years
Journal of Paleolimnology, 2006Co-Authors: Fasong Yuan, Braddock K. Linsley, Stephen S. HoweAbstract:Walker Lake, a Hydrologically closed, saline, alkaline lake located along the western margin of the Great Basin of western United States, has experienced a 77% reduction in volume and commitment drop in lake level as a result of anthropogenic perturbations and climatic fluctuations over the last century. The history of lake-level change in Walker Lake has been recorded instrumentally since 1860. A high-resolution multi-proxy sediment core record from Walker Lake has been generated through analysis of total inorganic carbon (TIC), total organic carbon (TOC), and oxygen and carbon isotope ratios (δ18O and δ13 C) of both downcore bulk TIC and ostracods over the last 200 yr. This allows us to examine how these sediment indices respond to actual changes in this lake’s Hydrologic Balance at interannual to decadal timescales. In Walker Lake sediments, changes in %TIC, %TOC, and δ13C and δ18O of TIC and ostracods are all associated to varying degrees with changes in the lake’s Hydrologic Balance, with δ18O of the TIC fraction (δ18OTIC) being the most highly correlated and the most effective Hydrologic indicator in this closed-basin lake. The δ18OTIC record from Walker Lake nearly parallels the instrumental lake-level record back to 1860. However, comparison with sporadic lake-water δ18O and dissolved inorganic carbon δ13C (δ13CDIC) results spanning the last several decades suggests that the isotopic values of downcore carbonate sediments may not be readily translated into absolute or even relative values of corresponding lake-water δ18O and δ13CDIC. Changes in the lake’s Hydrologic Balance usually lead to changes in isotopic composition of lake waters and downcore sediments, but not all the variations in downcore isotopic composition are necessarily caused by Hydrologic changes.
Carmelo Cammalleri - One of the best experts on this subject based on the ideXlab platform.
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state and parameter update in a coupled energy Hydrologic Balance model using ensemble kalman filtering
Journal of Hydrology, 2012Co-Authors: Carmelo Cammalleri, Giuseppe CiraoloAbstract:Summary The capability to accurately monitor and describe daily evapotranspiration (ET) in a cost effective manner is generally attributed to Hydrological models. However, continuous solution of energy and water Balance provides precise estimations only when a detailed knowledge of sub-surface characteristics is available. On the other hand, residual surface energy Balance models, based on remote observation of land surface temperature, are characterised by sufficient accuracy, but their applicability is limited by the lack of high frequency and high resolution thermal data. A compromise between these two methodologies is represented by the use of data assimilation scheme to include sparse remote estimates of surface fluxes into continuous modelling. This paper aims to test the combined use of coupled energy/water budget model and data assimilation schemes to assess daily evapotranspiration at field scale in a typical Mediterranean environment characterised by sparse olive trees. The continuous model was applied at hourly scale using remote multispectral images in the short-wave and standard meteorological information. The model was validated by means of contextual micro-meteorological information adopting the best available parameterisation (including root zone depth). The validation suggests an accuracy of about 35 W m−2 for the hourly turbulent fluxes and of about 0.3–0.4 mm d−1 for the daily ET. Successively, two data assimilation schemes based on the ensemble version of the Kalman filter were tested under the hypothesis of absence of information about the root zone depth. The application of a dual state-parameter filter (2EnKF) allows to obtain results very close to the ‘optimal’ ones independently from the value adopted as initial of root zone depth. Moreover, these results were obtained both by assimilating synthetic ‘perfect’ observations and ‘real’ remotely-derived estimations of latent heat flux. The methodology, which combines a coupled energy/water budget model and a dual state-parameter assimilation scheme, seems to be suitable to provide precise estimations of daily ET also when information on root zone depth are absent or not enough accurate.
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actual evapotranspiration assessment by means of a coupled energy Hydrologic Balance model validation over an olive grove by means of scintillometry and measurements of soil water contents
Journal of Hydrology, 2010Co-Authors: Carmelo Cammalleri, Giuseppe Ciraolo, C Agnese, M Minacapilli, Giuseppe Provenzano, Giovanni RalloAbstract:Summary A coupled energy/Hydrologic model was applied to simulate the exchange of energy and water in the soil–plant-atmosphere system (SPA). The model, which uses a “two-source” approach to estimate the energy fluxes, and the “force-restore” approach to represent the water Balance, was validated by means of evapotranspiration measurements collected via scintillometry and soil moisture measurements collected via time domain reflectometry (TDR) in a Sicilian olive grove. The comparison between measured and estimated fluxes values at an hourly scale showed good agreement. Additional comparisons on a daily timescale confirmed the model’s applicability for quantifying crop water requirements. Also in terms of daily evapotranspiration and soil water content values, the obtained results confirmed the model’s applicability for those practical applications aiming to quantify the crop water requirement. Moreover, further studies should be conducted to test the feasibility of using this model for long term simulations over a broad range of conditions.
