Climate change and climate variability, population growth, land use drive the need for new hydrologic knowledge understanding. In mountainous West other similar areas worldwide, three pressing needs stand out: first, to better understand processes controlling partitioning of energy water fluxes within out from these systems; second, feedbacks between hydrological biogeochemical ecological processes; and, third, enhance our physical empirical understanding with integrated measurement...

High‐resolution (∼11 km) regional climate modeling shows total annual precipitation on the Greenland ice sheet for 1958–2007 to be up 24% and surface mass balance 63% higher than previously thought. The largest differences occur in coastal southeast Greenland, where much resolution facilitates capturing snow accumulation peaks that past five‐fold coarser models missed. trend over full period reveals classic pattern expected a warming climate, with increased snowfall interior enhanced runoff...

This study examines the air temperature/stream temperature relationship at a geographically diverse set of streams. We evaluate general relationships (both linear and nonlinear) that apply to these streams, then examine how changes in stream associated with climate variability or warming might affect dissolved oxygen levels. The majority streams showed an increase water about 0.6–0.8°C for every 1°C temperature, very few displaying 1:1 air/water trend. For most nonlinear model produced...

Using data from a water‐balance instrument cluster with spatially distributed sensors we determined the magnitude and within‐catchment variability of components catchment‐scale water balance, focusing on relationship seasonal evapotranspiration to changes in snowpack soil moisture storage. Co‐located, continuous snow depth measurements were deployed rain–snow transition catchment mixed‐conifer forest Southern Sierra Nevada. At each elevation placed open, under canopy, at drip edge both...

Significance Climate change has the potential to reduce supply of surface water by accelerating mountain vegetation growth and evapotranspiration (ET), though likelihood severity this effect are poorly known. We used upper Kings River basin in California’s Sierra Nevada as a case study sensitivity runoff increased ET with warming. found that flow is highly sensitive expansion; warming projected for 2100 could increase across watershed 28% decrease riverflow 26%. Moreover, we consistent...

Abstract Increasing drought frequency and severity in a warming climate threaten forest ecosystems with widespread tree deaths. Canopy structure is important regulating mortality during drought, but how it functions remains controversial. Here, we show that the interplay between size explains drought-induced 2012-2016 California drought. Through an analysis of over one million trees, find rate follows “negative-positive-negative” piecewise relationship height, maintains consistent negative...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBacteriophage adsorption during transport through porous media: chemical perturbations and reversibilityRoger C. Bales, Stephen R. Hinkle, Thomas W. Kroeger, Kristen Stocking, Charles P. GerbaCite this: Environ. Sci. Technol. 1991, 25, 12, 2088–2095Publication Date (Print):December 1, 1991Publication History Published online1 May 2002Published inissue 1 December...

The spatial distribution of snow water equivalent (SWE) within 16‐, 4‐, and 1‐km 2 grid elements surrounding six telemetry (SNOTEL) stations in the Rio Grande headwaters was characterized using field observations snowpack properties, satellite data, binary regression tree models, a spatially distributed net radiation/temperature index mass balance model. In some cases, SNOTEL SWE values were 200% greater than mean element SWE. Analyses designed to identify optimal location for measuring...

We combined observations from four eddy covariance towers with remote sensing to better understand the altitudinal patterns of climate, plant phenology, Gross Ecosystem CO 2 Uptake, and Evapotranspiration (ET) around Upper Kings River basin in southern Sierra Nevada Mountains. Precipitation (P) increased elevation ∼500 m, more gradually at higher elevations, while vegetation graded savanna 405 m evergreen oak pine forest mid‐montane subalpine 2700 m. uptake transpiration peaked spring (March...

Abstract Water managers, cattle ranchers, and wildland fire managers face several barriers to effectively using climate forecasts. Repeatedly, these decision makers state that they lack any quantitative basis for evaluating forecast credibility. That is because the evaluations currently available typically reflect forecaster perspectives rather thanthose of users, or are not in forms users can easily obtain understand. Seasonal climateforecasts evaluated from perspective distinct user...

Regression tree models have been shown to provide the most accurate estimates of distributed snow water equivalent (SWE) when intensive field observations are available. This work presents a comparison regression using different source digital elevation (DEMs) and combinations independent variables. Different residual interpolation techniques also compared. The analysis was performed in 19·1 km2 Tokopah Basin, located southern Sierra Nevada California. Snow depth, dependent variable...

Inverse weighted distance and regression nonexact techniques were evaluated for interpolating methods snow water equivalent (SWE) across the entire Colorado River Basin of western United States. A 1‐km spacing was used gridding telemetry (SNOTEL) measurements years 1993, 1998, 1999, which on average, represented higher than lower average years. Because terrain effects, (hypsometric elevation multivariate physiographic parameter) found to be superior approaches (inverse weighting squared,...

We present a modeling approach that couples information about snow cover duration from remote sensing with distributed energy balance model to calculate the spatial distribution of water equivalence (SWE) in 1.2 km 2 mountain basin at peak accumulation season. In situ measurements incident solar radiation, longwave air temperature, relative humidity, and wind speed were around on basis topography. Snow surface albedo was assumed be spatially constant decrease time. Distributed temperature...

[1] We present a reconstruction of the Greenland Ice Sheet surface mass balance (SMB) from 1870 to 2010, based on merged Twentieth Century Reanalysis (20CR) and European Centre for Medium-Range Weather Forecasts (ECMWF) meteorological reanalyses, we compare our new SMB series with global regional climate atmospheric circulation indices during this period. demonstrate good agreement between annual constructed 20CR ECMWF reanalyses common period overlap show statistically significant long-term...

Bacteriophage transport was investigated in laboratory column experiments using sandy soil, a controlled field study wash, and fractured rock. In the soil columns, phage MS-2 exhibited significant dispersion excluded from 35 to 40% of void volume but did not adsorb. Dispersion similiar that observed laboratory. The f2 largely porous matrix two fractured-rock cores studied, coming through 1.2 2.0 times later than predicted on basis fracture flow alone. Because diffusion, nonsorbing solutes...

Abstract We live at the dynamic interface between solid Earth and its outer fluid envelopes. This interface, extending from vegetation canopy to base of active groundwater, was recently named Critical Zone because it supports life is increasingly impacted by human actions. Understanding complex interactions processes that operate in shape requires interdisciplinary approaches span wide spatial temporal scales. Tectonic processes, weathering, transport, biological control function structure...

An updated accumulation map for Greenland is presented on the basis of 39 new ice core estimates accumulation, 256 sheet from cores and snow pits used in previous maps, reanalysis time series data 20 coastal weather stations. The period 1950–2000 better represented by than are earlier periods. Ice‐sheet‐wide was estimated based kriging. average (95% confidence interval, or ±2 times standard error) over 30.0 ± 2.4 g cm −2 a −1 , with above 2000‐m elevation being essentially same, 29.9 2.2 ....

Enhanced understanding of subsurface water storage will improve prediction future impacts climate change, including drought, forest mortality, wildland fire, and strained security. Previous research has examined the importance plant‐accessible in soil, but upland landscapes within Mediterranean climates, soil often accounts for only a fraction storage. We draw insights from previous case study Southern Sierra Critical Zone Observatory to define attributes storage; review observed patterns...

Past estimates of Greenland Ice Sheet accumulation rates have been multiyear climatologies based on ice/firn cores and coastal precipitation records. Existing annually resolved incompletely quantified uncertainty, owing primarily to incomplete spatial coverage. This study improves upon these shortcomings by calibrating annual (1958–2007) solid output from the Fifth Generation Mesoscale Model modified for polar climates (Polar MM5) using firn core meteorological station data. The calibration...

Mountain runoff ultimately reflects the difference between precipitation (P) and evapotranspiration (ET), as modulated by biogeophysical mechanisms that intensify or alleviate drought impacts. These modulating are seldom measured not fully understood. The impact of warm 2012-15 California on heavily instrumented Kings River basin provides an extraordinary opportunity to enumerate four controlled mountain hydrology. Two intensified impact: (i) evaporative processes have first access local...

Abstract. The critical zone (CZ), the dynamic living skin of Earth, extends from top vegetative canopy through soil and down to fresh bedrock bottom groundwater. All humans live in depend on CZ. This has three co-evolving surfaces: canopy, ground surface, a deep subsurface below which Earth's materials are unweathered. network nine CZ observatories supported by US National Science Foundation made advances broad areas research relating surfaces. First, monitoring revealed how natural...

Hunsaker, Carolyn T., Thomas W. Whitaker, and Roger C. Bales, 2012. Snowmelt Runoff Water Yield Along Elevation Temperature Gradients in California’s Southern Sierra Nevada. Journal of the American Resources Association (JAWRA) 48(4): 667‐678. DOI: 10.1111/j.1752‐1688.2012.00641.x Abstract: Differences hydrologic response across rain‐snow transition southern Nevada were studied eight headwater catchments – Kings River Experimental Watersheds using continuous precipitation, snowpack,...

Interior Antarctica is among the most remote places on Earth and was thought to be beyond reach of human impacts when Amundsen Scott raced South Pole in 1911. Here we show detailed measurements from an extensive array 16 ice cores quantifying substantial toxic heavy metal lead pollution at throughout by 1889 – beating polar explorers more than 22 years. Unlike Arctic where peaked 1970s, as high early 20th century any time since industrialization. The similar timing magnitude changes...