|
Showing 1 - 25 of
37 matches in All Departments
Water-resources data for the 2004 water year for North Carolina
consist of records of stage, discharge, water quality for streams;
stage and contents for lakes and reservoirs; precipitation; and
ground-water levels and water quality of ground water. Volume 1
contains discharge records for 217 gaging stations; stage and
contents for 58 lakes and reservoirs; stage only records for 22
gaging stations; elevations for 9 stations; water quality for 39
gaging stations and 5 miscellaneous sites, and continuous water
quality for 35 sites; and continuous precipitation at 127 sites.
Volume 2 contains ground-water-level data from 161 observation
wells, ground-water-quality data from 38 wells, continuous water
quality for 7 sites and continuous precipitation at 7 sites.
Additional water data were collected at 51 sites not involved in
the systematic data-collection program, and are published as
miscellaneous measurements in Volume 1. The collection of
water-resources data in North Carolina is a part of the National
Water-Data System operated by the U.S. Geological Survey in
cooperation with State, municipal, and Federal agencies.
Weather and climate are strong drivers of population dynamics,
plant and animal spatial distributions, community interactions, and
ecosystem states. Information on local weather and climate is
crucial in interpreting trends and patterns in the natural
environment for resource management, research, and visitor
enjoyment. This document describes the weather and climate
monitoring program at the Channel Islands National Park (fig. 1),
initiated in the 1990s. Manual and automated stations, which
continue to evolve as technology changes, are being used for this
program. The document reviews the history of weather data
collection on each of the five Channel Islands National Park
islands, presents program administrative structure, and provides an
overview of procedures for data collection, archival, retrieval,
and reporting. This program overview is accompanied by the 'Channel
Islands National Park Remote Automated Weather Station Field
Handbook' and the 'Channel Islands National Park Ranger Weather
Station Field Handbook'. These Handbooks are maintained separately
at the Channel Island National Park as 'live documents' that are
updated as needed to provide a current working manual of weather
and climate monitoring procedures. They are available on request
from the Weather Program Manager (Channel Islands National Park,
1901 Spinnaker Dr., Ventura, CA 93001; 805.658.5700). The two Field
Handbooks describe in detail protocols for managing the four remote
automated weather stations (RAWS) and the seven manual Ranger
Weather Stations on the islands, including standard operating
procedures for equipment maintenance and calibration; manufacturer
operating manuals; data retrieval and archiving; metada collection
and archival; and local, agency, and vendor contracts.
A new analytical method for the determination of elements in
filtered aqueous matrices using inductively coupled plasma-mass
spectrometry (ICP-MS) has been implemented at the U.S. Geological
Survey National Water Quality Laboratory that uses
collision/reaction cell technology to reduce molecular ion
interferences. The updated method can be used to determine elements
in filtered natural-water and other filtered aqueous matrices,
including whole-water, biota, sediment, and soil digestates. Helium
or hydrogen is used as the collision or reaction gas, respectively,
to eliminate or substantially reduce interferences commonly
resulting from sample-matrix composition. Helium is used for
molecular ion interferences associated with the determination of
As, Co, Cr, Cu, K, Mg, Na, Ni, V, W and Zn, whereas hydrogen is
used for Ca, Fe, Se, and Si. Other elements that are not affected
by molecular ion interference also can be determined simply by not
introducing a collision/reaction gas into the cell. Analysis time
is increased by about a factor of 2 over the previous method
because of the additional data acquisition time in the hydrogen and
helium modes. Method detection limits for As, Ca, Co, Cr, Cu, Fe,
K, Mg, Na, Ni, Se, Si (as SiO2), V, W, and Zn, all of which use a
collision/reaction gas, are 0.06 microgram per liter (?g/L) As,
0.04 milligram per liter (mg/L) Ca, 0.02 ?g/L Co, 0.02 ?g/L Cr,
0.04 ?g/L Cu, 1 ?g/L Fe, 0.007 mg/L K, 0.009 mg/L Mg, 0.09 mg/L Na,
0.05 ?g/L Ni, 0.04 ?g/L Se, 0.03 mg/L SiO2, 0.05 ?g/L V, 0.03 ?g/L
W, and 0.04 ?g/L Zn. Most method detection limits are lower or
relatively unchanged compared to earlier methods except for Co, K,
Mg, Ni, SiO2, and Tl, which are less than a factor of 2 higher.
Percentage bias for samples spiked at about one-third and
two-thirds of the concentration of the highest calibration standard
ranged from -8.1 to 7.9 percent for reagent water, -14 to 21
percent for surface water, and -16 to 16 percent for ground water.
The percen
The United States Geological Survey (USGS) is a scientific agency
of the United States government. The scientists of the USGS study
the landscape of the United States, its natural resources, and the
natural hazards that threaten it. The agency lives by its motto:
"Science for a changing world." The USGS publishes technical
reports, data series, investigation results, and procedural
documents for internal USGS use and the general public. These
publications include titles like Lithium Use in Batteries, Sound
Data Management, and Groundwater Qualities Across the Nation.
The United States Geological Survey (USGS) is a scientific agency
of the United States government. The scientists of the USGS study
the landscape of the United States, its natural resources, and the
natural hazards that threaten it. The agency lives by its motto:
"Science for a changing world."
This report documents the addition of shared node Local Grid
Refinement (LGR) to MODFLOW-2005, the U.S. Geological Survey
modular, transient, three-dimensional, finite-difference
ground-water flow model. LGR provides the capability to simulate
ground-water flow using one block-shaped higher-resolution local
grid (a child model) within a coarser-grid parent model. LGR
accomplishes this by iteratively coupling two separate MODFLOW-2005
models such that heads and fluxes are balanced across the shared
interfacing boundary. LGR can be used in two-and three-dimensional,
steady-state and transient simulations and for simulations of
confined and unconfined ground-water systems. Traditional one-way
coupled telescopic mesh refinement (TMR) methods can have large,
often undetected, inconsistencies in heads and fluxes across the
interface between two model grids. The iteratively coupled
shared-node method of LGR provides a more rigorous coupling in
which the solution accuracy is controlled by convergence criteria
defined by the user. In realistic problems, this can result in
substantially more accurate solutions and require an increase in
computer processing time. The rigorous coupling enables sensitivity
analysis, parameter estimation, and uncertainty analysis that
reflects conditions in both model grids. This report describes the
method used by LGR, evaluates LGR accuracy and performance for two-
and three-dimensional test cases, provides input instructions, and
lists selected input and output files for an example problem. It
also presents the Boundary Flow and Head (BFH) Package, which
allows the child and parent models to be simulated independently
using the boundary conditions obtained through the iterative
process of LGR.
The United States Geological Survey (USGS) is a scientific agency
of the United States government. The scientists of the USGS study
the landscape of the United States, its natural resources, and the
natural hazards that threaten it. The agency lives by its motto:
"Science for a changing world." The USGS publishes technical
reports, data series, investigation results, and procedural
documents for internal USGS use and the general public. These
publications include titles like Lithium Use in Batteries, Sound
Data Management, and Groundwater Qualities Across the Nation.
The United States Geological Survey (USGS) is a scientific agency
of the United States government. The scientists of the USGS study
the landscape of the United States, its natural resources, and the
natural hazards that threaten it. The agency lives by its motto:
"Science for a changing world."
The United States Geological Survey (USGS) is a scientific agency
of the United States government. The scientists of the USGS study
the landscape of the United States, its natural resources, and the
natural hazards that threaten it. The agency lives by its motto:
"Science for a changing world." The USGS publishes technical
reports, data series, investigation results, and procedural
documents for internal USGS use and the general public. These
publications include titles like Lithium Use in Batteries, Sound
Data Management, and Groundwater Qualities Across the Nation.
The United States Geological Survey (USGS) is a scientific agency
of the United States government. The scientists of the USGS study
the landscape of the United States, its natural resources, and the
natural hazards that threaten it. The agency lives by its motto:
"Science for a changing world." The USGS publishes technical
reports, data series, investigation results, and procedural
documents for internal USGS use and the general public. These
publications include titles like Lithium Use in Batteries, Sound
Data Management, and Groundwater Qualities Across the Nation.
Water-resources data for the 2004 water year for Texas are
presented in six volumes, and consist of records of stage,
discharge, and water quality of streams and canals; stage,
contents, and water-quality of lakes and reservoirs; and water
levels and water quality of ground-water wells. Volume 4 contains
records for water discharge at 68 gaging stations; elevation at 14
lakes and reservoirs; and water quality at 30 gaging stations. Also
included are data for 11 partial-record stations comprised of 3
flood-hydrograph, 7 low-flow, and 1 crest-stage station. Also
included are lists of discontinued surface-water discharge or
stage-only stations and discontinued surface- water-quality
stations. Additional water data were collected at various sites,
not part of the systematic data-collection program, and are
published as miscellaneous measurements. These data represent that
part of the National Water Data System operated by the U.S.
Geological Survey and cooperating Federal, State, and local
agencies in Texas. Records for a few pertinent stations in the
bordering States also are included.
The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code
1710 is to present a method to determine the 13C of dissolved
inorganic carbon (DIC) of water. The DIC of water is precipitated
using ammoniacal strontium chloride (SrCl2) solution to form
strontium carbonate (SrCO3). The 13C is analyzed by reacting SrCO3
with 100-percent phosphoric acid (H3PO4) to liberate carbon
quantitatively as carbon dioxide (CO2), which is collected,
purified by vacuum sublimation, and analyzed by dual inlet
isotope-ratio mass spectrometry (DI-IRMS). The DI-IRMS is a DuPont
double-focusing mass spectrometer. One ion beam passes through a
slit in a forward collector and is collected in the rear collector.
The other measurable ion beams are collected in the front
collector. By changing the ion-accelerating voltage under computer
control, the instrument is capable of measuring mass/charge (m/z)
45 or 46 in the rear collector and m/z 44 and 46 or 44 and 45,
respectively, in the front collector. The ion beams from these m/z
values are as follows: m/z 44 = CO2 = 12C16O16O, m/z 45 = CO2 =
13C16O16O primarily, and m/z 46 = CO2 = 12C16O18O primarily. The
data acquisition and control software calculates 13C values.
When beginning hydrologic investigations, a first action is often
to gather existing sources of well information, compile this
information into a single dataset, and visualize this information
in a geographic information system (GIS) environment. This report
presents tools (macros) developed using Visual Basic for
Applications (VBA) for Microsoft Excel 2007 to assist in these
tasks. One tool combines multiple datasets into a single worksheet
and formats the resulting data for use by the other tools. A second
tool produces summary information about the dataset, such as a list
of unique site identification numbers, the number of water-level
observations for each, and a table of the number of sites with a
listed number of water-level observations. A third tool creates
subsets of the original dataset based on user-specified options and
produces a worksheet with water-level information for each well in
the subset, including the average and standard deviation of
water-level observations and maximum decline and rise in water
levels between any two observations, among other information. This
water-level information worksheet can be imported directly into
ESRI ArcMap as an 'XY Data' file, and each of the fields of summary
well information can be used for custom display. A separate set of
VBA tools distributed in an additional Excel workbook creates
hydrograph charts of each of the wells in the data subset produced
by the aforementioned tools and produces portable document format
(PDF) versions of the hydrograph charts. These PDF hydrographs can
be hyperlinked to well locations in ArcMap or other GIS
applications.
|
You may like...
Loot
Nadine Gordimer
Paperback
(2)
R398
R330
Discovery Miles 3 300
Loot
Nadine Gordimer
Paperback
(2)
R398
R330
Discovery Miles 3 300
|