Identification_Information: Citation: Citation_Information: Originator: Reheis, Marith C. Originator: Kihl, Rolf Publication_Date: 1995 Title: Dust Deposition in Southern Nevada and California, 1984- 1989: Relations to climate, source area, and lithology Edition: 1 Series_Information: Series_Name: Journal of Geophysical Research Issue_Identification: volume 100(D5), pages 8893-8918 Publication_Information: Publication_Place: Publisher: Online_Linkage: Description: Abstract: Dust samples taken annually for five years from 55 sites in southern Nevada and California provide an unparalleled source of information on modern rates of dust deposition, grain size, and mineralogical and chemical composition. The relations of modern dust to climatic factors, type and lithology of dust source, and regional wind patterns shed new light on the processes of dust entrainment and deposition. A project to study modern dust deposition relative to soils in southern Nevada and California was initiated in 1984 under the auspices of the Yucca Mountain Site Characterization Project (Interagency Agreement DE-AI08-78ET44802). The primary purpose of the dust-deposition project was to provide data on modern dust composition and influx rates to a computer model relating soil carbonate to paleoclimate. A secondary purpose was to provide data on dust influx rates at specific sites in the southern Great Basin and Mojave Desert where soil chronosequences were studied in support of tectonic and stratigraphic investigations for the Yucca Mountain Project. The initial 46 sampling sites, including one site with five traps, were established in 1984 and were supplemented by nine more sites in 1985 to provide dust data to soil studies by other investigators along the Elsinore Fault and in the Transverse Ranges of southern California. Purpose: The purpose of this research is to obtain data on the composition and deposition rate of eolian dust in southern Nevada and California from 1984 to 1989, and to relate these properties to controlling variables such as climate, lithology of local dust source, and type of source. Further work will relate modern dust to soil properties and compare modern rates of dust influx with long-term rates estimated from soils at selected sites. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1984 Ending_Date: 1989 Currentness_Reference: 1984 was the first year dust traps were deployed for this study; 1989 was the last year in which dust samples described in this report were collected. Status: Progress: Complete Maintenance_and_Update_Frequency: Irregular Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -118.0 East_Bounding_Coordinate: -114.0 North_Bounding_Coordinate: 38.25 South_Bounding_Coordinate: 32.50 Keywords: Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Dust Theme_Keyword: Dust deposition rates Theme_Keyword: Chemistry Theme_Keyword: Mineralogy Place: Place_Keyword_Thesaurus: None Place_Keyword: CA Place_Keyword: California Place_Keyword: NV Place_Keyword: Nevada Access_Constraints: none Use_Constraints: none Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Marith Reheis Contact_Address: Address_Type: mailing address Address: Box 25046, MS 913 U.S. Geological Survey Denver Federal Center City: Denver State_or_Province: CO Postal_Code: 80225-0046 Country: USA Contact_Voice_Telephone: (303) 236-1270 Contact_Facsimile_Telephone: (303) 236-0214 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Samples were obtained from the dust traps by carefully washing the marbles, screen, and pan with distilled water into plastic liter bottles. In the laboratory, the sample was gradually dried at about 35°C in large evaporating dishes; coarse organic material is removed during this process. Subsequent analyses on dust samples included, in the order they were performed: (1) moisture, (2) organic matter, (3) soluble salts and gypsum, (4) total carbonate (calcite plus dolomite), (5) grain size, (6) major-oxide chemistry, and (7) mineralogy (sand, silt, and clay fractions). The database for any given site commonly contains gaps depending on how far the sample for a particular year could be stretched through the analytical cascade. In some cases, samples from different years at the same site or adjacent sites were combined to obtain enough material for measuring grain size. A sample was commonly retrieved and used in more than one analysis if the first analytical procedure used was non- destructive. These sequential analytical techniques included: (1) Moisture and organic-matter content (Walkley- Black procedure in Black, 1965) were measured on the same split using 0.05 g. (2) The entire sample was used to extract the solution to measure soluble salts (Jackson, 1958) and was then dried and recovered; thus, subsequent analyses were performed on samples without soluble salts. (3) A 0.25-g split was used to analyze total carbonate (Chittick procedure in Singer and Janitzky, 1986). This split, free of carbonate after the analysis, was recovered and used to analyze for major oxides and zirconium. (4) When sufficient sample (0.4g) existed to obtain grain size using the Sedigraph rather than by pipette analysis, the clay and silt fractions were saved and used to analyze mineralogy by X-ray diffraction. Most of the laboratory analyses were performed in the Sedimentation Laboratory of the Institute of Arctic and Alpine Research in Boulder, Colorado, using standard laboratory techniques for soil samples (see Black, 1965, and Singer and Janitzky, 1986) that we adapted for use on very small samples (the non-organic content of a dust sample collected from one trap typically weighs less than 1 g/yr). These adaptations generally result in larger standard errors than normal for the results of different techniques because the amount of sample used is smaller than the recommended amount. Logical_Consistency_Report: The sampling design for this study was not statistically based; rather, sites were chosen to provide data on dust influx at soil- study sites and to answer specific questions about the relations of dust to local source lithology and type, distance from source, and climate. Some sites were chosen for their proximity to potential dust sources of different lithologic composition (for example, playas versus granitic, calcic, or mafic alluvial fans). Other sites were placed along transects crossing topographic barriers downwind from a dust source. These transects include sites east of Tonopah (43-46) crossing the rhyolitic Kawich Range, sites downwind of northern (40, 35, 36) and central Death Valley ( 38, 39, 11-14) crossing the mixed-lithology Grapevine and Funeral Mountains, respectively, and sites downwind of Desert Dry Lake crossing the calcareous Sheep Range (47-50) north of Las Vegas. In addition, some sites were chosen for their proximity to weather stations. Specific locations for dust traps were chosen on the basis of the above criteria plus accessibility, absence of dirt roads or other artificially disturbed areas upwind, and inconspicuousness. The last factor is important because the sites are not protected or monitored; hence, most sites are at least 0.5 mile from a road or trail. Despite these precautions, dust traps are sometimes tampered with, often violently. This is a particular problem in areas close to population centers, and most of these sites (52-55 near Los Angeles and 17-19 and 22 near Las Vegas) have been abandoned. A few other sites, mostly those that appeared to be greatly influenced by nearby farming (20, 21, and 41), were eliminated in 1989. Dust traps were also generally placed in flat, relatively open areas to mitigate wind-eddy effects created by tall vegetation or topographic irregularities. See notes in the Attribute_Accuracy_Report regarding combination of samples too small for individual analyses. Generally the data from ICP, oxides, and mineralogy are for combined samples. Completeness_Report: The 55 sites established in 1984 and 1985 were sampled annually through 1989 in order to establish an adequate statistical basis to calculate annual dust flux. Sampling continues at 37 of these sites (many sites now have two or more dust traps) every two or three years as opportunity and funding permit. The most important factors that influenced dust-trap design in this study were: (1) measuring the amount of dust added to soils; (2) sampling on an annual basis; (3) no protection other than being hard to find; and (4) the cost and ready availability of components that might have to be replaced from sources in small towns. The original design consists of a single-piece Teflon- coated angel-food cake pan (see note 1) painted flat black on the outside to maximize water evaporation and mounted on a steel fence post about 2 m above the ground. A circular piece of 1/4-inch- mesh galvanized hardware cloth is fitted into the pan so that it rests 3-4 cm below the rim, and glass marbles fill the upper part of the pan above the hardware cloth. The Teflon coating is non- reactive and adds no mineral contamination to the dust sample should it flake. The hardware cloth resists weathering under normal conditions. The 2-m height eliminates most sand-sized particles that travel by saltation rather than by suspension in air; sand grains are not generally pertinent to soil genesis because they are too large to be translocated downward into soil profiles. The marbles imitate the effect of a gravelly fan surface and prevent dust that has filtered or washed into the bottom of the pan from being blown away. The empty space below the hardware cloth provides a reservoir that prevents water from overflowing the pan during large storms. This basic design was modified in 1986 in two ways. In many areas, the traps became favored perching sites for a wide variety of birds. As a result, significant amounts of non-eolian sediment were locally added to the samples (as much as five times the normal amount of dust at some sites). All dust traps were fitted with two metal straps looped in an inverted basket shape over the top and the top surfaces of the straps were coated with Tanglefoot1. This sticky material never dries (although it eventually becomes saturated with dust and must be reapplied) and effectively discourages birds from roosting. In addition, extra dust traps surrounded by alter- type wind baffles were constructed at four sites characterized by different plant communities. These communities and sites are: blackbrush (Coleogyne ramosissima), creosote bush (Larrea divaricata), and other low brushy plants at sites 1-5 on Fortymile Wash; Joshua tree (Yucca brevifolia), other tall yucca species, and blackbrush at site 18 on the Kyle Canyon fan; pinyon-juniper (Pinus monophylla-Juniperus sp) at site 7 on Pahute Mesa; and acacia (acacia sp), creosote bush, and blackbrush at site 26 near the McCoy Mountains. The wind baffles imitate the effect of ground-level wind speed at the 2-m height of the dust trap and permit comparison of the amount of dust caught by an unshielded trap with the amount that should be caught at ground level where vegetation breaks the wind. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Trap locations were ascertained by plotting their positions on USGS topographic maps at 1:24000 scale. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: National Climatic Data Center Publication_Date: 1961-1990 Title: California: Climatological Data Annual Summary Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1992 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: NCDC 61-90 A CA Source_Contribution: Data used to calculate mean annual temperature (MAT) and mean annual precipitation (MAP) at dust trap sites Source_Information: Source_Citation: Citation_Information: Originator: National Climatic Data Center Publication_Date: 1961-1990 Title: Nevada: Climatological Data Annual Summary Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1992 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: NCDC 61-90 A NV Source_Contribution: Data used to calculate mean annual temperature (MAT) and mean annual precipitation (MAP) at dust trap sites Source_Information: Source_Citation: Citation_Information: Originator: National Climatic Data Center Publication_Date: 1992 Title: California: Monthly station normals of temperature, precipitation, and heating and cooling degree days 1961-1990 Series_Information: Series_Name: Climatography of the United States Issue_Identification: 81 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1992 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: NCDC 61-90 M CA Source_Contribution: Data used to calculate mean annual temperature (MAT) and mean annual precipitation (MAP) at dust trap sites Source_Information: Source_Citation: Citation_Information: Originator: National Climatic Data Center Publication_Date: 1992 Title: Nevada: Monthly station normals of temperature, precipitation, and heating and cooling degree days 1961-1990 Series_Information: Series_Name: Climatography of the United States Issue_Identification: 81 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1992 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: NCDC 61-90 M NV Source_Contribution: Data used to calculate mean annual temperature (MAT) and mean annual precipitation (MAP) at dust trap sites Source_Information: Source_Citation: Citation_Information: Originator: U.S. Department of Commerce (Weather Bureau) Publication_Date: 1964 Title: California: Climatic summary of the United States-- Supplement for 1951 through 1960 Series_Information: Series_Name: Climatography of the United States Issue_Identification: 86-4 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1964 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: DOC 51-60 CA Source_Contribution: Data used to calculate mean annual temperature (MAT) and mean annual precipitation (MAP) at dust trap sites Source_Information: Source_Citation: Citation_Information: Originator: U.S. Department of Commerce (Weather Bureau) Publication_Date: 1964 Title: Nevada: Climatic summary of the United States-- Supplement for 1951 through 1960 Series_Information: Series_Name: Climatography of the United States Issue_Identification: 86-4 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1964 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: DOC 51-60 NV Source_Contribution: Data used to calculate mean annual temperature (MAT) and mean annual precipitation (MAP) at dust trap sites Process_Step: Process_Description: The most important factors that influenced dust-trap design in this study were: (1) measuring the amount of dust added to soils; (2) sampling on an annual basis; (3) no protection other than being hard to find; and (4) the cost and ready availability of components that might have to be replaced from sources in small towns. The original design consists of a single-piece Teflon-coated angel-food cake pan (see note 1) painted flat black on the outside to maximize water evaporation and mounted on a steel fence post about 2 m above the ground. A circular piece of 1/4- inch-mesh galvanized hardware cloth is fitted into the pan so that it rests 3-4 cm below the rim, and glass marbles fill the upper part of the pan above the hardware cloth. The Teflon coating is non-reactive and adds no mineral contamination to the dust sample should it flake. The hardware cloth resists weathering under normal conditions. The 2-m height eliminates most sand-sized particles that travel by saltation rather than by suspension in air; sand grains are not generally pertinent to soil genesis because they are too large to be translocated downward into soil profiles. The marbles imitate the effect of a gravelly fan surface and prevent dust that has filtered or washed into the bottom of the pan from being blown away. The empty space below the hardware cloth provides a reservoir that prevents water from overflowing the pan during large storms. This basic design was modified in 1986 in two ways. In many areas, the traps became favored perching sites for a wide variety of birds. As a result, significant amounts of non-eolian sediment were locally added to the samples (as much as five times the normal amount of dust at some sites). All dust traps were fitted with two metal straps looped in an inverted basket shape over the top and the top surfaces of the straps were coated with Tanglefoot. [Use of trade names by the U.S. Geological Survey does not constitute an endorsement of the product.] This sticky material never dries (although it eventually becomes saturated with dust and must be reapplied) and effectively discourages birds from roosting. In addition, extra dust traps surrounded by alter-type wind baffles were constructed at four sites characterized by different plant communities. These communities and sites are: blackbrush (Coleogyne ramosissima), creosote bush (Larrea divaricata), and other low brushy plants at sites 1-5 on Fortymile Wash; Joshua tree (Yucca brevifolia), other tall yucca species, and blackbrush at site 18 on the Kyle Canyon fan; pinyon- juniper (Pinus monophylla-Juniperus sp) at site 7 on Pahute Mesa; and acacia (acacia sp), creosote bush, and blackbrush at site 26 near the McCoy Mountains. The wind baffles imitate the effect of ground-level wind speed at the 2-m height of the dust trap and permit comparison of the amount of dust caught by an unshielded trap with the amount that should be caught at ground level where vegetation breaks the wind. Process_Date: 1984 Process_Step: Process_Description: Samples were obtained from the dust traps by carefully washing the marbles, screen, and pan with distilled water into plastic liter bottles. In the laboratory, the sample was gradually dried at about 35°C in large evaporating dishes; coarse organic material is removed during this process. Subsequent analyses on dust samples included, in the order they were performed: (1) moisture, (2) organic matter, (3) soluble salts and gypsum, (4) total carbonate (calcite plus dolomite), (5) grain size, (6) major-oxide chemistry, and (7) mineralogy (sand, silt, and clay fractions). The database for any given site commonly contains gaps depending on how far the sample for a particular year could be stretched through the analytical cascade. In some cases, samples from different years at the same site or adjacent sites were combined to obtain enough material for measuring grain size. A sample was commonly retrieved and used in more than one analysis if the first analytical procedure used was non- destructive. These sequential analytical techniques included: (1) Moisture and organic-matter content (Walkley- Black procedure in Black, 1965) were measured on the same split using 0.05 g. (2) The entire sample was used to extract the solution to measure soluble salts (Jackson, 1958) and was then dried and recovered; thus, subsequent analyses were performed on samples without soluble salts. (3) A 0.25-g split was used to analyze total carbonate (Chittick procedure in Singer and Janitzky, 1986). This split, free of carbonate after the analysis, was recovered and used to analyze for major oxides and zirconium. (4) When sufficient sample (0.4 g) existed to obtain grain size using the Sedigraph rather than by pipette analysis, the clay and silt fractions were saved and used to analyze mineralogy by X-ray diffraction. Most of the laboratory analyses were performed in the Sedimentation Laboratory of the Institute of Arctic and Alpine Research in Boulder, Colorado, using standard laboratory techniques for soil samples (see Black, 1965, and Singer and Janitzky, 1986) that we adapted for use on very small samples (the non-organic content of a dust sample collected from one trap typically weighs less than 1 g/yr). These adaptations generally result in larger standard errors than normal for the results of different techniques because the amount of sample used is smaller than the recommended amount. Process_Date: 1985 Process_Step: Process_Description: Total dust flux is calculated by multiplying the mineral weight times the fraction less than 2 mm times the pan area times the fraction of year during which the sample accumulated (in file labdust.xls, number of days divided by 365). Other dust-flux values for various components (i. e. silt flux) are calculated by multiplying the total dust flux by the percentage of the component. Preliminary examination of the flux data indicated that samples from some sites collected in 1985 and 1986, before the trap design was modified to discourage birds from roosting, were anomalously large (50-500% greater) compared to those collected in later years. All of the anomalous samples had been recorded as having significant amounts of bird feces at the time of collection. Consultations with bird biologists confirmed that bird droppings can contain significant amounts of mineral matter, mostly derived from cropstones; the amount varies with the species and with the diet of local populations of individual species. Moreover, perching birds can contaminate the sample with material from their feet. In some cases, we have evidence of near-deliberate contamination in the form of one or two pebble-sized clasts of local rocks that were found in samples, possibly dropped (or swapped for marbles) by large birds such as ravens. Data from samples with large amounts of bird droppings were discarded from further analysis and were excluded from the computations of "selected average" flux values. Process_Date: 1987 Process_Step: Process_Description: Major elements were measured in U.S. Geological Survey laboratories on a split of the less-than-2mm fraction remaining after analysis and removal of carbonate by the Chittick method. Major elements and zirconium were analyzed by induction-coupled plasma spectroscopy (Lichte and others, 1987). In some cases, samples from different years at the same site or adjacent sites were combined to obtain enough material for measuring major-oxide composition. Process_Date: 1988 Process_Step: Process_Description: Major oxides are calculated from elemental compositions (file dusticp.txt) using the following equations based on atomic weights: > SiO2 = Si/0.467 > Al2O3 = Al/0.529 > Fe2O3 = Fe/0.699 > MgO = Mg/0.603 > CaO = Ca/0.715 > Na2O = Na/0.742 > K2O = K /0.830 > TiO2 = Ti/0.599 > MnO = Mn/0.774 > ZrO2 = Zr/0.740 The percentages of major oxides and zirconium were then recalculated to 100%, excluding water, volatiles, and minor elements, and the ratios of major oxides to ZrO2 are based on the recalculated values. Process_Date: 1988 Process_Step: Process_Description: Mineralogy was measured in U.S. Geological Survey laboratories on splits of samples that had been previously analyzed for grain size. Samples of sand, silt, and clay were slurried in water (sand samples were ground to a fine powder) and mounted dropwise on glass slides. Minerals in the sand and silt fractions were identified by characteristic peaks on X-ray diffractograms and their relative amounts were estimated by measuring peak heights. Minerals in the clay samples were identified by characteristic peaks obtained after the following treatments: air-dried, glycolated, and heated to 300 degrees C and 550 degrees C. The relative abundances of clay minerals were estimated by measuring the following peak heights (in degrees 2 theta) and adjusted for intensity variations between runs using the peak height of quartz at 26.65 2 theta: chlorite, 6.3 on the 550 degrees C trace; kaolinite, 12.6 on the glycolated trace minus the amount of chlorite; mica, 8.8 on the glycolated trace; smectite, 5.2 on the glycolated trace; mixed-layer mica- smectite, 8.85 on the 550 degrees trace minus the amounts of mica and smectite. Process_Date: 1988 Process_Step: Process_Description: The National Climatic Data Center no longer publishes mean climatic data for the entire length of record at weather stations. To obtain mean annual temperature (MAT) and precipitation (MAP) for the weather stations nearest the dust traps, averages had to be computed from climatic summaries of the United States (U.S. Department of Commerce, 1952, 1965), from station normals for 1961-1990 (National Climatic Data Center, 1992), and from various climatological data annual summaries. Comparisons could then be made of the long-term averages with those for the five years of dust collection (file climate.xls). Process_Date: 1993 Source_Used_Citation_Abbreviation: DOC 51-60 CA Source_Used_Citation_Abbreviation: DOC 51-60 NV Source_Used_Citation_Abbreviation: NCDC 61-90 A CA Source_Used_Citation_Abbreviation: NCDC 61-90 M CA Source_Used_Citation_Abbreviation: NCDC 61-90 A NV Source_Used_Citation_Abbreviation: NCDC 61-90 M NV Process_Step: Process_Description: The dust-trap sites are at different elevations from the nearest weather stations. To estimate mean annual temperature (MAT) and precipitation (MAP) at the sampling sites, annual climate data for the entire period of record was obtained for every weather station in the region, including some that are no longer maintained but excluding those in coastal California. The data in this file was combined from the data in file aveclim.xls, which included the weather stations nearest the traps, and from climatic data for other stations. For many stations with relatively complete records, this involved computation of the averages of MAT and MAP (columns under "MAT calculations" and "MAP calculations") compiled from records prior to 1961, the last year in which averages for the entire length of record were published by the U.S. Department of Commerce (1965), and from station normals for 1961-1990 (National Climatic Data Center, 1992). Normals and averages are not published for stations with missing data or those which were moved at some time; for these stations, the computation required hand-entering data for each year of record from the climatological data annual summaries (columns under "MAT records" and "MAP records"). Linear regression (bottom left of file) was used to obtain equations that relate temperature and precipitation to elevation for these weather stations (columns "Elevation", "MAT", and "MAP") and to estimate these parameters at sampling sites with different elevations. For temperature, only one equation was required; it provides estimates with a standard error (s.e.) of only 1.3 degrees C. For precipitation, equations were most useful when the stations were divided into three geographic regions, including the area of the Mexican border and the Colorado River-southeast Nevada corridor (s.e.=2.6 cm), southwestern California east of the Transverse Ranges (s.e.=8.6 cm), and the interior deserts (s.e.=2.0 cm). Process_Date: 1993 Source_Used_Citation_Abbreviation: DOC 51-60 CA Source_Used_Citation_Abbreviation: DOC 51-60 NV Source_Used_Citation_Abbreviation: NCDC 61-90 A CA Source_Used_Citation_Abbreviation: NCDC 61-90 M CA Source_Used_Citation_Abbreviation: NCDC 61-90 A NV Source_Used_Citation_Abbreviation: NCDC 61-90 M NV Process_Step: Process_Description: Estimates of MAP and MAT listed under "this study" were obtained using the linear regression equations calculated from data in file regclim.xls. These equations are: > MAT = -0.0072E+23.4 > MAP (interior deserts) = 0.00555E+7.075 > MAP (Colo.R.-Salton Sea) = 0.01013+7.468 > MAP (SW Calif.) = 0.05E+5.002 where E is elevation in meters. For comparison, MAP is also calculated using other published equations. For stations on the Nevada Test Site (T-1 through T-9) I used the equation of Quiring (1983), in which y = MAP in inches and x = elevation in thousands of feet: > y = 1.36x - 0.51 For stations in southern Nevada, including the Nevada Test Site, I used the equations of French (1983), in which y = MAP in inches and x = elevation in feet. French (1983) divided southern Nevada roughly into thirds based on the paths of moisture-carrying air masses from the west and south; the eastern third has the most rainfall, the western third has the least, and the central third is intermediate: > Eastern: log y = 0.0000933x + 0.486 > Central: log y = 0.0000786x + 0.446 > Western: log y = 0.0000365x + 0.505 MAP at the closest weather station to the dust-trap site is also given. Estimates of MAP for sites near Los Angeles, including T-51 through T-54, using the equations from this study gave unrealistically low values (see file trapclim.xls) because this area is under a coastal rather than an interior climate. Thus, in the papers written using these data, MAP for these sites is assumed to be about the same as that at the nearest weather station. Process_Date: 1993 Process_Step: Process_Description: Mean monthly precipitation and temperature from 1984 to 1989 were acquired from the National Climatic Data Center (1984-1989) for weather stations in southern Nevada and California that were closest to dust-trap sites and entered into a spreadsheet in order to calculate mean annual values for climatic variables and compare them to long-term means (calculated in file aveclim.xls). Seasonal precipitation (May-October and November-April) was calculated from monthly values. Process_Date: 1993 Process_Step: Process_Description: Secondary climatic variables were calculated from the data in file climate.txt These secondary variables include monthly and annual potential evapotranspiration (PET) and the leaching index (LI) of Arkley (1963). The leaching index is a measure of available moisture obtained by subtracting monthly evapotranspiration from monthly precipitation. PET was calculated for all stations with both temperature and precipitation data using the method of Thornthwaite (1948), and for stations with mean minimum and maximum temperatures using the method of Papadakis (1965). The leaching index is calculated for both methods of PET. Pan evaporation measurements are also given where available (National Climatic Data Center and Farnsworth and others, 1982) for comparison. PET is more readily calculated by the Thornthwaite method than by the Papadakis method, because the latter requires mean minimum and maximum temperatures that are commonly not recorded at some weather stations. However, according to Taylor (1986), the Thornthwaite method applied to climatic data for arid regions yields PET values that are much too low (as much as 150% compared to evaporation-pan data for the growing season). The Papadakis method provides estimates of PET that are closest to pan data in arid climates. Many thanks to Emily Taylor (U.S. Geological Survey) for guiding me through the complex calculations of PET and providing me with the appropriate references. [Editor's note: These equations contain expressions that cannot be conveniently represented in plain ASCII text. Accordingly, I have coded the expressions using the notation of the programming language BASIC, hoping that most people will understand that. BASIC has no subscripting, however, so I used the underscore to indicate that the next character or two is subscripted. The correct notations can be obtained by examining the original document, in Microsoft Word for DOS format.] > LI = (P - PET) summed for each month in which P > PET. > > PET (Thornthwaite) = F(1.6(10t/I)^a) > > where > t temperature (degrees C) for the month > I sum for 12 months of (t/5)^1.514 (given in column "heat factor I") > a (6.75*10^(-7) * I^3) - (7.71* 10^(-5) * I^2) + (0.1792 * I) + 0.49239 (given in column "exponent a") > F day length factor (from table V in Thornthwaite, 1948) > > PET (Papadakis) = 5.625 (e_ma - e_d) > > where > e_ma is saturation vapor pressure of monthly average daily maximum temperature (mbars) > e_d is monthly average vapor pressure (dew point) (mbars) According to Lindsley and others (1975, p. 35), vapour pressures are calculated by: > e_ma = (33.869(0.00738 (max.T) + 0.8072)^8 - 0.00019 |1.8 (max.T) | + 0.001316) > e_d = (33.869(0.00738 (min.T) + 0.8072)^8 - 0.00019 |1.8 (min.T) | + 0.001316) where max.T is the monthly average maximum temperature and min.T is the monthly average minimum temperature. [Editor's note: Here are the preceding equations rendered in TeX: > {\parskip=\medskipamount > $LI = (P - PET)$ summed for each month in which $P > PET$. > $$PET (\hbox{Thornthwaite}) = F(1.6(10t/I)^a)$$ > where > $$\halign{\quad # \hfil & \quad # \hfil\cr > $t$ & temperature (degrees C) for the month\cr > $I$ & sum for twelve months of $(t/5)^{1.514}$ (given in column ``heat factor I'')\cr > $a$ & $(6.75 \times 10^{-7}I^3) - (7.71 \times 10^{-5}I^2) + (0.1792I) + 0.49239$ (given in column ``exponent a'')\cr > $F$ & day length factor (from table V in Thornthwaite, 1948)\cr > }$$ > $$PET (\hbox{Papadakis}) = 5.625 (e_{ma} - e_d)$$ > where > $$\halign{\quad # \hfil & \quad # \hfil\cr > $e_{ma}$ & is the saturation vapor pressure of monthly average daily maximum temperature (in mbar), and \cr > $e_d$ & is the monthly average vapor pressure (dew point) in mbars\cr > }$$ > According to Lindsley and others (1975, p. 35), vapor pressures are calculated by: > $$e_{ma} = (33.869(0.00738 (\hbox{max.T}) + 0.8072)^8 - 0.00019 \vert 1.8 (\hbox{max.T}) \vert + 0.001316)$$ > $$e_d = (33.869(0.00738 (\hbox{min.T}) + 0.8072)^8 - 0.00019 \vert 1.8 (\hbox{min.T}) \vert + 0.001316)$$ > where max.T is the monthly average maximum temperature and min.T is the monthly average minimum temperature. > } [Editor's note: end of TeX rendition of the equations.] Process_Date: 1993 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Point Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity Point Point_and_Vector_Object_Count: 101 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.01 Longitude_Resolution: 0.01 Geographic_Coordinate_Units: Decimal degrees Entity_and_Attribute_Information: Overview_Description Entity_and_Attribute_Overview: This data set contains 430 distinct attributes, some of which directly describe entities and some merely qualify the values of other attributes. Documenting these attributes using the detailed form of the Content Standards for Digital Geospatial Metadata is possible in principle but cannot be carried out in a timely fashion. In general the attributes describe two types of entities, dust samples collected from traps deployed in Southwestern Nevada and nearby California, and weather stations nearby the dust collection sites. These observations are coded in ASCII tables in which the rows typically refer to the entities and the columns typically refer to characteristics of those entities. Here is a list of attributes, sorted by the name of the file in which they appear, the column within the file, and giving the column heading that identifies the attribute. > Core/meta/samples.txt 1 Trap sample id > Core/meta/samples.txt 2 Lab No. (GRL-) > Core/meta/samples.txt 3 Days out > Core/meta/samples.txt 4 Problem? > Core/meta/trapsite.txt 1 trap > Core/meta/trapsite.txt 2 latitude > Core/meta/trapsite.txt 3 longitude > Core/meta/trapsite.txt 4 elevation (m) > Core/meta/trapsite.txt 5 geographic area > Core/meta/trapsite.txt 6 transect (km)* > Core/meta/trapsite.txt 7 primary source source** > Core/meta/trapsite.txt 8 primary source lithology*** > Core/meta/trapsite.txt 9 secondary source source** > Core/meta/trapsite.txt 10 secondary source lithology** > Core/raw/labdust.txt 1 Trap sample id > Core/raw/labdust.txt 2 Lab# (GRL-) > Core/raw/labdust.txt 3 Days out > Core/raw/labdust.txt 4 Organic carbon % > Core/raw/labdust.txt 5 Organic matter % > Core/raw/labdust.txt 6 %CaCO3 (total) > Core/raw/labdust.txt 7 %CaCO3 (OM-free) > Core/raw/labdust.txt 8 %salts (total) > Core/raw/labdust.txt 9 %salts (OM-free) > Core/raw/labdust.txt 10 %gypsum (total) > Core/raw/labdust.txt 11 %gypsum (OM-free) > Core/raw/labdust.txt 12 Mineral wt (g)** > Core/raw/labdust.txt 13 % <2mm > Core/raw/labdust.txt 14 sand % of <2mm fraction > Core/raw/labdust.txt 15 silt % of <2mm fraction > Core/raw/labdust.txt 16 clay % of <2mm fraction > Core/raw/labdust.txt 17 textural class > Core/raw/flux.txt 1 Trap > Core/raw/flux.txt 2 CO3 > Core/raw/flux.txt 3 salt > Core/raw/flux.txt 4 gypsum > Core/raw/flux.txt 5 min_wgt_Q > Core/raw/flux.txt 6 min_wgt > Core/raw/flux.txt 7 dustflux_Q > Core/raw/flux.txt 8 dustflux > Core/raw/flux.txt 9 CO3_flux_Q > Core/raw/flux.txt 10 CO3_flux > Core/raw/flux.txt 11 saltflux_Q > Core/raw/flux.txt 12 saltflux > Core/raw/flux.txt 13 gypsflux_Q > Core/raw/flux.txt 14 gypsflux > Core/raw/flux.txt 15 sandflux_Q > Core/raw/flux.txt 16 sandflux > Core/raw/flux.txt 17 siltflux_Q > Core/raw/flux.txt 18 siltflux > Core/raw/flux.txt 19 clayflux_Q > Core/raw/flux.txt 20 clayflux > Core/raw/flux_avg.txt 1 Trap > Core/raw/flux_avg.txt 2 CO3_avg > Core/raw/flux_avg.txt 3 salt_avg > Core/raw/flux_avg.txt 4 gypsum_avg > Core/raw/flux_avg.txt 5 min_wgt_avg > Core/raw/flux_avg.txt 6 min_wgt_sel_avg > Core/raw/flux_avg.txt 7 dustflux_avg > Core/raw/flux_avg.txt 8 dustflux_sel_avg > Core/raw/flux_avg.txt 9 CO3_flux_avg > Core/raw/flux_avg.txt 10 CO3_flux_sel_avg > Core/raw/flux_avg.txt 11 saltflux_avg > Core/raw/flux_avg.txt 12 saltflux_sel_avg > Core/raw/flux_avg.txt 13 gypsflux_avg > Core/raw/flux_avg.txt 14 gypsflux_sel_avg > Core/raw/flux_avg.txt 15 sandflux_avg > Core/raw/flux_avg.txt 16 sandflux_sel_avg > Core/raw/flux_avg.txt 17 siltflux_avg > Core/raw/flux_avg.txt 18 siltflux_sel_avg > Core/raw/flux_avg.txt 19 clayflux_avg > Core/raw/flux_avg.txt 20 clayflux_sel_avg > Core/raw/flux/CO3.txt 1 Trap > Core/raw/flux/CO3.txt 2 1985 > Core/raw/flux/CO3.txt 3 1986 > Core/raw/flux/CO3.txt 4 1987 > Core/raw/flux/CO3.txt 5 1988 > Core/raw/flux/CO3.txt 6 1989 > Core/raw/flux/CO3.txt 7 average > Core/raw/flux/CO3.txt 8 Selected average > Core/raw/flux/salt.txt 1 Trap > Core/raw/flux/salt.txt 2 1985 > Core/raw/flux/salt.txt 3 1986 > Core/raw/flux/salt.txt 4 1987 > Core/raw/flux/salt.txt 5 1988 > Core/raw/flux/salt.txt 6 1989 > Core/raw/flux/salt.txt 7 average > Core/raw/flux/salt.txt 8 Selected average > Core/raw/flux/gypsum.txt 1 Trap > Core/raw/flux/gypsum.txt 2 1985 > Core/raw/flux/gypsum.txt 3 1986 > Core/raw/flux/gypsum.txt 4 1987 > Core/raw/flux/gypsum.txt 5 1988 > Core/raw/flux/gypsum.txt 6 1989 > Core/raw/flux/gypsum.txt 7 average > Core/raw/flux/gypsum.txt 8 Selected average > Core/raw/flux/min_wgt.txt 1 Trap > Core/raw/flux/min_wgt.txt 2 Q85 > Core/raw/flux/min_wgt.txt 3 1985 > Core/raw/flux/min_wgt.txt 4 Q86 > Core/raw/flux/min_wgt.txt 5 1986 > Core/raw/flux/min_wgt.txt 6 Q87 > Core/raw/flux/min_wgt.txt 7 1987 > Core/raw/flux/min_wgt.txt 8 Q88 > Core/raw/flux/min_wgt.txt 9 1988 > Core/raw/flux/min_wgt.txt 10 Q89 > Core/raw/flux/min_wgt.txt 11 1989 > Core/raw/flux/min_wgt.txt 12 average > Core/raw/flux/min_wgt.txt 13 Selected average > Core/raw/flux/CO3_flux.txt 1 Trap > Core/raw/flux/CO3_flux.txt 2 Q85 > Core/raw/flux/CO3_flux.txt 3 1985 > Core/raw/flux/CO3_flux.txt 4 Q86 > Core/raw/flux/CO3_flux.txt 5 1986 > Core/raw/flux/CO3_flux.txt 6 Q87 > Core/raw/flux/CO3_flux.txt 7 1987 > Core/raw/flux/CO3_flux.txt 8 Q88 > Core/raw/flux/CO3_flux.txt 9 1988 > Core/raw/flux/CO3_flux.txt 10 Q89 > Core/raw/flux/CO3_flux.txt 11 1989 > Core/raw/flux/CO3_flux.txt 12 average > Core/raw/flux/CO3_flux.txt 13 Selected average > Core/raw/flux/saltflux.txt 1 Trap > Core/raw/flux/saltflux.txt 2 Q85 > Core/raw/flux/saltflux.txt 3 1985 > Core/raw/flux/saltflux.txt 4 Q86 > Core/raw/flux/saltflux.txt 5 1986 > Core/raw/flux/saltflux.txt 6 Q87 > Core/raw/flux/saltflux.txt 7 1987 > Core/raw/flux/saltflux.txt 8 Q88 > Core/raw/flux/saltflux.txt 9 1988 > Core/raw/flux/saltflux.txt 10 Q89 > Core/raw/flux/saltflux.txt 11 1989 > Core/raw/flux/saltflux.txt 12 average > Core/raw/flux/saltflux.txt 13 Selected average > Core/raw/flux/gypsflux.txt 1 Trap > Core/raw/flux/gypsflux.txt 2 Q85 > Core/raw/flux/gypsflux.txt 3 1985 > Core/raw/flux/gypsflux.txt 4 Q86 > Core/raw/flux/gypsflux.txt 5 1986 > Core/raw/flux/gypsflux.txt 6 Q87 > Core/raw/flux/gypsflux.txt 7 1987 > Core/raw/flux/gypsflux.txt 8 Q88 > Core/raw/flux/gypsflux.txt 9 1988 > Core/raw/flux/gypsflux.txt 10 Q89 > Core/raw/flux/gypsflux.txt 11 1989 > Core/raw/flux/gypsflux.txt 12 average > Core/raw/flux/gypsflux.txt 13 Selected average > Core/raw/flux/dustflux.txt 1 Trap > Core/raw/flux/dustflux.txt 2 Q85 > Core/raw/flux/dustflux.txt 3 1985 > Core/raw/flux/dustflux.txt 4 Q86 > Core/raw/flux/dustflux.txt 5 1986 > Core/raw/flux/dustflux.txt 6 Q87 > Core/raw/flux/dustflux.txt 7 1987 > Core/raw/flux/dustflux.txt 8 Q88 > Core/raw/flux/dustflux.txt 9 1988 > Core/raw/flux/dustflux.txt 10 Q89 > Core/raw/flux/dustflux.txt 11 1989 > Core/raw/flux/dustflux.txt 12 average > Core/raw/flux/dustflux.txt 13 Selected average > Core/raw/flux/sandflux.txt 1 Trap > Core/raw/flux/sandflux.txt 2 Q85 > Core/raw/flux/sandflux.txt 3 1985 > Core/raw/flux/sandflux.txt 4 Q86 > Core/raw/flux/sandflux.txt 5 1986 > Core/raw/flux/sandflux.txt 6 Q87 > Core/raw/flux/sandflux.txt 7 1987 > Core/raw/flux/sandflux.txt 8 Q88 > Core/raw/flux/sandflux.txt 9 1988 > Core/raw/flux/sandflux.txt 10 Q89 > Core/raw/flux/sandflux.txt 11 1989 > Core/raw/flux/sandflux.txt 12 average > Core/raw/flux/sandflux.txt 13 Selected average > Core/raw/flux/siltflux.txt 1 Trap > Core/raw/flux/siltflux.txt 2 Q85 > Core/raw/flux/siltflux.txt 3 1985 > Core/raw/flux/siltflux.txt 4 Q86 > Core/raw/flux/siltflux.txt 5 1986 > Core/raw/flux/siltflux.txt 6 Q87 > Core/raw/flux/siltflux.txt 7 1987 > Core/raw/flux/siltflux.txt 8 Q88 > Core/raw/flux/siltflux.txt 9 1988 > Core/raw/flux/siltflux.txt 10 Q89 > Core/raw/flux/siltflux.txt 11 1989 > Core/raw/flux/siltflux.txt 12 average > Core/raw/flux/siltflux.txt 13 Selected average > Core/raw/flux/clayflux.txt 1 Trap > Core/raw/flux/clayflux.txt 2 Q85 > Core/raw/flux/clayflux.txt 3 1985 > Core/raw/flux/clayflux.txt 4 Q86 > Core/raw/flux/clayflux.txt 5 1986 > Core/raw/flux/clayflux.txt 6 Q87 > Core/raw/flux/clayflux.txt 7 1987 > Core/raw/flux/clayflux.txt 8 Q88 > Core/raw/flux/clayflux.txt 9 1988 > Core/raw/flux/clayflux.txt 10 Q89 > Core/raw/flux/clayflux.txt 11 1989 > Core/raw/flux/clayflux.txt 12 average > Core/raw/flux/clayflux.txt 13 Selected average > Core/raw/minerals/claymin.txt 1 Sample no. > Core/raw/minerals/claymin.txt 2 Chlorite > Core/raw/minerals/claymin.txt 3 Kaolinite > Core/raw/minerals/claymin.txt 4 Mica > Core/raw/minerals/claymin.txt 5 Smectite > Core/raw/minerals/claymin.txt 6 Mixed-layer > Core/raw/minerals/claymin.txt 7 Quartz > Core/raw/minerals/claymin.txt 8 Other > Core/raw/minerals/sandmin.txt 1 Sample no. > Core/raw/minerals/sandmin.txt 2 Quartz > Core/raw/minerals/sandmin.txt 3 Anorthoclase > Core/raw/minerals/sandmin.txt 4 High-temp sanidine > Core/raw/minerals/sandmin.txt 5 High-temp albite > Core/raw/minerals/sandmin.txt 6 Anorthite > Core/raw/minerals/sandmin.txt 7 Orthoclase > Core/raw/minerals/sandmin.txt 8 Microcline > Core/raw/minerals/sandmin.txt 9 Low-temp albite > Core/raw/minerals/sandmin.txt 10 Muscovite + biotite > Core/raw/minerals/sandmin.txt 11 Pyroxene > Core/raw/minerals/sandmin.txt 12 Hornblende* > Core/raw/minerals/sandmin.txt 13 Dolomite > Core/raw/minerals/sandmin.txt 14 Calcite > Core/raw/minerals/sandmin.txt 15 Other > Core/raw/minerals/siltmin.txt 1 Sample no. > Core/raw/minerals/siltmin.txt 2 Quartz > Core/raw/minerals/siltmin.txt 3 Anorthoclase > Core/raw/minerals/siltmin.txt 4 High-temp sanidine > Core/raw/minerals/siltmin.txt 5 High-temp albite > Core/raw/minerals/siltmin.txt 6 Anorthite > Core/raw/minerals/siltmin.txt 7 Orthoclase > Core/raw/minerals/siltmin.txt 8 Microcline > Core/raw/minerals/siltmin.txt 9 Low-temp albite > Core/raw/minerals/siltmin.txt 10 Muscovite + biotite > Core/raw/minerals/siltmin.txt 11 Chlorite > Core/raw/minerals/siltmin.txt 12 Apatite > Core/raw/minerals/siltmin.txt 13 Pyroxene > Core/raw/minerals/siltmin.txt 14 Hornblende* > Core/raw/minerals/siltmin.txt 15 Dolomite > Core/raw/minerals/siltmin.txt 16 Other > Core/raw/minerals/combine.txt 1 combined sample id > Core/raw/minerals/combine.txt 2 component sample 1 > Core/raw/minerals/combine.txt 3 component sample 2 > Core/raw/minerals/combine.txt 4 component sample 3 > Core/raw/minerals/combine.txt 5 component sample 4 > Core/raw/minerals/combine.txt 6 component sample 5 > Core/raw/minerals/combine.txt 7 component sample 6 > Core/raw/chemistry/dusticp.txt 1 Traps > Core/raw/chemistry/dusticp.txt 2 Si > Core/raw/chemistry/dusticp.txt 3 Al > Core/raw/chemistry/dusticp.txt 4 Fe > Core/raw/chemistry/dusticp.txt 5 Mg > Core/raw/chemistry/dusticp.txt 6 Ca > Core/raw/chemistry/dusticp.txt 7 Na > Core/raw/chemistry/dusticp.txt 8 K > Core/raw/chemistry/dusticp.txt 9 Ti > Core/raw/chemistry/dusticp.txt 10 Mn > Core/raw/chemistry/dusticp.txt 11 Zr > Core/raw/chemistry/dustox.txt 1 Traps > Core/raw/chemistry/dustox.txt 2 raw SiO2 > Core/raw/chemistry/dustox.txt 3 raw Al2O3 > Core/raw/chemistry/dustox.txt 4 raw Fe2O3 > Core/raw/chemistry/dustox.txt 5 raw MgO > Core/raw/chemistry/dustox.txt 6 raw CaO > Core/raw/chemistry/dustox.txt 7 raw Na2O > Core/raw/chemistry/dustox.txt 8 raw K2O > Core/raw/chemistry/dustox.txt 9 raw TiO2 > Core/raw/chemistry/dustox.txt 10 raw MnO > Core/raw/chemistry/dustox.txt 11 raw ZrO2 > Core/raw/chemistry/dustox.txt 12 norm SiO2 > Core/raw/chemistry/dustox.txt 13 norm Al2O3 > Core/raw/chemistry/dustox.txt 14 norm Fe2O3 > Core/raw/chemistry/dustox.txt 15 norm MgO > Core/raw/chemistry/dustox.txt 16 norm CaO > Core/raw/chemistry/dustox.txt 17 norm Na2O > Core/raw/chemistry/dustox.txt 18 norm K2O > Core/raw/chemistry/dustox.txt 19 norm TiO2 > Core/raw/chemistry/dustox.txt 20 norm MnO > Core/raw/chemistry/dustox.txt 21 norm ZrO2 > Core/raw/chemistry/dustox.txt 22 Si/Zr02 > Core/raw/chemistry/dustox.txt 23 Al/Zr02 > Core/raw/chemistry/dustox.txt 24 Fe/Zr02 > Core/raw/chemistry/dustox.txt 25 Mg/Zr02 > Core/raw/chemistry/dustox.txt 26 Ca/Zr02 > Core/raw/chemistry/dustox.txt 27 Na/Zr02 > Core/raw/chemistry/dustox.txt 28 K/Zr02 > Core/raw/chemistry/dustox.txt 29 Ti/Zr02 > Core/raw/chemistry/dustox.txt 30 Mn/Zr02 > Core/raw/climate/climreg.txt 1 Station > Core/raw/climate/climreg.txt 2 Group > Core/raw/climate/climreg.txt 3 Elevation > Core/raw/climate/climreg.txt 4 MAT > Core/raw/climate/climreg.txt 5 MAP > Core/raw/climate/climreg.txt 6 number of yrs<1961 > Core/raw/climate/climreg.txt 7 MAT before 1961 > Core/raw/climate/climreg.txt 8 number of years1961-90 > Core/raw/climate/climreg.txt 9 MAT from 1961-90 > Core/raw/climate/climreg.txt 10 number of yrs<1961 > Core/raw/climate/climreg.txt 11 MAP before 1961 > Core/raw/climate/climreg.txt 12 number of years1961-90 > Core/raw/climate/climreg.txt 13 MAP from 1961-90 > Core/raw/climate/climreg.txt 14 1961 MAT records 1961 through 1990 > Core/raw/climate/climreg.txt 15 1962 > Core/raw/climate/climreg.txt 16 1963 > Core/raw/climate/climreg.txt 17 1964 > Core/raw/climate/climreg.txt 18 1965 > Core/raw/climate/climreg.txt 19 1966 > Core/raw/climate/climreg.txt 20 1967 > Core/raw/climate/climreg.txt 21 1968 > Core/raw/climate/climreg.txt 22 1969 > Core/raw/climate/climreg.txt 23 1970 > Core/raw/climate/climreg.txt 24 1971 > Core/raw/climate/climreg.txt 25 1972 > Core/raw/climate/climreg.txt 26 1973 > Core/raw/climate/climreg.txt 27 1974 > Core/raw/climate/climreg.txt 28 1975 > Core/raw/climate/climreg.txt 29 1976 > Core/raw/climate/climreg.txt 30 1977 > Core/raw/climate/climreg.txt 31 1978 > Core/raw/climate/climreg.txt 32 1979 > Core/raw/climate/climreg.txt 33 1980 > Core/raw/climate/climreg.txt 34 1981 > Core/raw/climate/climreg.txt 35 1982 > Core/raw/climate/climreg.txt 36 1983 > Core/raw/climate/climreg.txt 37 1984 > Core/raw/climate/climreg.txt 38 1985 > Core/raw/climate/climreg.txt 39 1986 > Core/raw/climate/climreg.txt 40 1987 > Core/raw/climate/climreg.txt 41 1988 > Core/raw/climate/climreg.txt 42 1989 > Core/raw/climate/climreg.txt 43 1990 > Core/raw/climate/climreg.txt 44 1961 MAP records 1961 through 1990 > Core/raw/climate/climreg.txt 45 1962 > Core/raw/climate/climreg.txt 46 1963 > Core/raw/climate/climreg.txt 47 1964 > Core/raw/climate/climreg.txt 48 1965 > Core/raw/climate/climreg.txt 49 1966 > Core/raw/climate/climreg.txt 50 1967 > Core/raw/climate/climreg.txt 51 1968 > Core/raw/climate/climreg.txt 52 1969 > Core/raw/climate/climreg.txt 53 1970 > Core/raw/climate/climreg.txt 54 1971 > Core/raw/climate/climreg.txt 55 1972 > Core/raw/climate/climreg.txt 56 1973 > Core/raw/climate/climreg.txt 57 1974 > Core/raw/climate/climreg.txt 58 1975 > Core/raw/climate/climreg.txt 59 1976 > Core/raw/climate/climreg.txt 60 1977 > Core/raw/climate/climreg.txt 61 1978 > Core/raw/climate/climreg.txt 62 1979 > Core/raw/climate/climreg.txt 63 1980 > Core/raw/climate/climreg.txt 64 1981 > Core/raw/climate/climreg.txt 65 1982 > Core/raw/climate/climreg.txt 66 1983 > Core/raw/climate/climreg.txt 67 1984 > Core/raw/climate/climreg.txt 68 1985 > Core/raw/climate/climreg.txt 69 1986 > Core/raw/climate/climreg.txt 70 1987 > Core/raw/climate/climreg.txt 71 1988 > Core/raw/climate/climreg.txt 72 1989 > Core/raw/climate/climreg.txt 73 1990 > Core/raw/climate/aveclim.txt 1 Station > Core/raw/climate/aveclim.txt 2 Time interval > Core/raw/climate/aveclim.txt 3 TJan > Core/raw/climate/aveclim.txt 4 TFeb > Core/raw/climate/aveclim.txt 5 TMar > Core/raw/climate/aveclim.txt 6 TApr > Core/raw/climate/aveclim.txt 7 TMay > Core/raw/climate/aveclim.txt 8 TJun > Core/raw/climate/aveclim.txt 9 TJul > Core/raw/climate/aveclim.txt 10 TAug > Core/raw/climate/aveclim.txt 11 TSep > Core/raw/climate/aveclim.txt 12 TOct > Core/raw/climate/aveclim.txt 13 TNov > Core/raw/climate/aveclim.txt 14 TDec > Core/raw/climate/aveclim.txt 15 Mean yearly temperature > Core/raw/climate/aveclim.txt 16 PJan > Core/raw/climate/aveclim.txt 17 PFeb > Core/raw/climate/aveclim.txt 18 PMar > Core/raw/climate/aveclim.txt 19 PApr > Core/raw/climate/aveclim.txt 20 PMay > Core/raw/climate/aveclim.txt 21 PJun > Core/raw/climate/aveclim.txt 22 PJul > Core/raw/climate/aveclim.txt 23 PAug > Core/raw/climate/aveclim.txt 24 PSep > Core/raw/climate/aveclim.txt 25 POct > Core/raw/climate/aveclim.txt 26 PNov > Core/raw/climate/aveclim.txt 27 PDec > Core/raw/climate/aveclim.txt 28 Annual total precipitation > Core/raw/climate/trapclim.txt 1 Trap > Core/raw/climate/trapclim.txt 2 Est MAT (+-1.3C) > Core/raw/climate/trapclim.txt 3 Est MAP (cm) > Core/raw/climate/trapclim.txt 4 s.e. MAP(cm) > Core/raw/climate/trapclim.txt 5 Quiring est. MAP (NTS) > Core/raw/climate/trapclim.txt 6 French est MAP (so NV) > Core/raw/climate/trapclim.txt 7 WS nearest > Core/raw/climate/trapclim.txt 8 WS Elevation (m) > Core/raw/climate/trapclim.txt 9 WS MAP (cm) > Core/raw/climate/climate.txt 1 Station > Core/raw/climate/climate.txt 2 State > Core/raw/climate/climate.txt 3 Latitude > Core/raw/climate/climate.txt 4 Longitude > Core/raw/climate/climate.txt 5 Elevation (m) > Core/raw/climate/climate.txt 6 Time interval > Core/raw/climate/climate.txt 7 TJan > Core/raw/climate/climate.txt 8 TFeb > Core/raw/climate/climate.txt 9 TMar > Core/raw/climate/climate.txt 10 TApr > Core/raw/climate/climate.txt 11 TMay > Core/raw/climate/climate.txt 12 TJun > Core/raw/climate/climate.txt 13 TJul > Core/raw/climate/climate.txt 14 TAug > Core/raw/climate/climate.txt 15 TSep > Core/raw/climate/climate.txt 16 TOct > Core/raw/climate/climate.txt 17 TNov > Core/raw/climate/climate.txt 18 TDec > Core/raw/climate/climate.txt 19 Mean annual T > Core/raw/climate/climate.txt 20 PJan > Core/raw/climate/climate.txt 21 PFeb > Core/raw/climate/climate.txt 22 PMar > Core/raw/climate/climate.txt 23 PApr > Core/raw/climate/climate.txt 24 PMay > Core/raw/climate/climate.txt 25 PJun > Core/raw/climate/climate.txt 26 PJul > Core/raw/climate/climate.txt 27 PAug > Core/raw/climate/climate.txt 28 PSep > Core/raw/climate/climate.txt 29 POct > Core/raw/climate/climate.txt 30 PNov > Core/raw/climate/climate.txt 31 PDec > Core/raw/climate/climate.txt 32 Total P > Core/raw/climate/climate.txt 33 PNov-Apr > Core/raw/climate/climate.txt 34 PMay-Oct Entity_and_Attribute_Detail_Citation: Fuller details are available in Core/meta/report.txt in this data set. Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Peter N. Schweitzer Contact_Address: Address_Type: mailing address Address: Mail Stop 918 National Center U.S. Geological Survey 12201 Sunrise Valley Drive City: Reston State_or_Province: VA Postal_Code: 22092 Country: USA Contact_Voice_Telephone: (703) 648-6533 Contact_Facsimile_Telephone: (703) 648-6560 Contact_Electronic_Mail_Address: pschweitzer@usgs.gov Resource_Description: Distribution_Liability Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: TEXT Format_Information_Content: Dust data Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: Network_Resource_Name: Online_Computer_and_Operating_System: Data General AViiON 6220 system running DG/UX version 5.4R3.10 (UNIX) Fees: none Metadata_Reference_Information: Metadata_Date: 19950720 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Peter N. Schweitzer Contact_Address: Address_Type: mailing address Address: Mail Stop 918 U.S. Geological Survey 12201 Sunrise Valley Drive City: Reston State_or_Province: VA Postal_Code: 20192 Country: USA Contact_Voice_Telephone: (703) 648-6533 Contact_Facsimile_Telephone: (703) 648-6560 Contact_Electronic_Mail_Address: pschweitzer@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: 19940608