Who Visits a National Park and What do They Get Out of It?: A Joint Visitor Cluster Analysis and Travel Cost Model for Yellowstone National Park

Yellowstone National Park visitor data were obtained from a survey collected for the National Park Service by the Park Studies Unit at the University of Idaho. Travel cost models have been conducted for national parks in the United States; however, this study builds on these studies and investigates how benefits vary by types of visitors who participate in different activities while at the park. Visitor clusters were developed based on activities in which a visitor participated while at the park. The clusters were analyzed and then incorporated into a travel cost model to determine the economic value (consumer surplus) that the different visitor groups received from visiting the park. The model was estimated using a zero-truncated negative binomial regression corrected for endogenous stratification. The travel cost price variable was estimated using both 1/3 and 1/4 the wage rate to test for sensitivity to opportunity cost specification. The average benefit across all visitor cluster groups was estimated at between $235 and $276 per person per trip. However, per trip benefits varied substantially across clusters; from $90 to $103 for the “value picnickers,” to $185–$263 for the “backcountry enthusiasts,” $189–$278 for the “do it all adventurists,” $204–$303 for the “windshield tourists,” and $323–$714 for the “creature comfort” cluster group.     

Seasonal changes in the free glycerol level in the body parts of the adult barnacle Balanus balanoides

Seasonal changes in the free glycerol level in body parts of the adult barnacle Balanus balanoides have been followed during the 1969 season. Glycerol levels were highest in winter when the barnacles were most cold-tolerant and lowest in summer when they were least cold-tolerant. It is suggested that glycerol, and possibly other solutes, may be concentrated in the blood of B. balanoides, thus promoting supercooling and reducing the amount of ice formed at sub-zero temperatures.     

Criteria and air-toxic emissions from in-use automobiles in the National Low-Emission Vehicle program

The U.S. Environmental Protection Agency (EPA) implemented a program to identify tailpipe emissions of criteria and air-toxic contaminants from in-use, light-duty low-emission vehicles (LEVs). EPA recruited 25 LEVs in 2002 and measured emissions on a chassis dynamometer using the cold-start urban dynamometer driving schedule of the Federal Test Procedure. The emissions measured included regulated pollutants, particulate matter, speciated hydrocarbon compounds, and carbonyl compounds. The results provided a comparison of emissions from real-world LEVs with emission standards for criteria and air-toxic compounds. Emission measurements indicated that a portion of the in-use fleet tested exceeded standards for the criteria gases. Real-time regulated and speciated hydrocarbon measurements demonstrated that the majority of emissions occurred during the initial phases of the cold-start portion of the urban dynamometer driving schedule. Overall, the study provided updated emission factor data for real-world, in-use operation of LEVs for improved emissions modeling and mobile source inventory development.     

Important meteorological data for use in risk assessment

This paper presents a methodology for the calculation of atmospheric stability classes in correlation with wind velocities for six sites of the Greek territory, namely Ellinikon (Athens), Elefsis, Megara, Heraklion, Chania and Patras, based on real data obtained from meteorological observations in these sites and on computations related with their geographic position. In addition to that, a comparison is presented of the atmospheric stability classes produced with online measurements for the Ellinikon (Athens) site with significant coincidence in the results.

These calculated values of the meteorological parameters (particularly of atmospheric stability) are most appropriate for uncertainty calculations in quantified risk assessments (QRAs) of hazardous installations sited in the above-mentioned areas, especially when risk and safety-related decisions need to be taken. Consequent results obtained with these parameters are more realistic compared to the “classical” assumption of D5/F2, which leads to significant diversification in the estimation of risk.     

Self-reported driving under the influence of alcohol and cannabis among Ontario students: Associations with graduated licensing,risk taking,and substance abuse

Objective: This article describes the patterns of self-reported driving under the influence of alcohol (DUIA) and driving under the influence of cannabis (DUIC) among licensed Ontario students in 2009 and examines their associations with graduated licensing, risk taking, and substance use problems for understanding DUIA and DUIC behaviors. Ontario's graduated licensing system requires new drivers to hold a G1 license for a minimum of 8 months and a G2 license for a minimum of 12 months before a full and unrestricted G license can be obtained. Among other restrictions, G1 drivers must maintain a 0 blood alcohol content (BAC), have an experienced driver in the passenger seat, not drive on any high-speed expressways, and not drive between the hours of midnight and 5 a.m. A G2 license is more similar to a G license, with fewer restrictions.

Method: This study analyzed data from the 2009 Ontario Student Drug Use and Health Survey (OSDUHS). The OSDUHS is a biennial population-based survey of students (grades 7 to 12) in Ontario, Canada.

Results: The results showed that 16.3% of licensed students in Ontario reported DUIC and 11.5% reported DUIA during the past year. After controlling for the effect of age, type of license emerged as a robust predictor for both DUIA and DUIC behavior, because students with a G2 and full license were significantly more likely to report DUIA and DUIC than drivers with a G1 license. Multivariate analyses suggested that risk-seeking behaviors were more important for understanding DUIA behavior than for DUIC behavior. Elevated problem indicators for alcohol and for cannabis were associated with DUIA and DUIC, respectively.

Conclusions: Though much attention has been paid to drinking and driving among adolescents, this research shows that more Ontario students now report driving after cannabis use than after drinking alcohol. The results identify important correlates of both behaviors that may be useful for prevention purposes.     

A comparison of antimony and lead profiles over the past 2500 years in Flanders Moss ombrotrophic peat bog, Scotland

Two cores collected in 2001 and 2004 from Flanders Moss ombrotrophic peat bog in central Scotland were dated (14C, 210Pb) and analysed (ICP-OES, ICP-MS) to derive and compare the historical atmospheric deposition records of Sb and Pb over the past 2500 years. After correction, via Sc, for contributions from soil dust, depositional fluxes of Sb and Pb peaked from ca. 1920-1960 A.D., with >95% of the anthropogenic inventories deposited post-1800 A.D. Over the past two centuries, trends in Sb and Pb deposition have been broadly similar, with fluctuations in the anthropogenic Sb/Pb ratio reflecting temporal variations in the relative input from emission sources such as the mining and smelting of Pb ores (in which Sb is commonly present, as at Leadhills/Wanlockhead in southern Scotland), combustion of coal (for which the Sb/Pb ratio is approximately an order of magnitude greater than in Pb ores) and exhaust emissions (Pb from leaded petrol) and abrasion products from the brake linings (Sb from heat-resistant Sb compounds) of automobiles. The influence of leaded petrol has been most noticeable in recent decades, firstly through the resultant minima in Sb/Pb and 206Pb/207Pb ratios (the latter arising from the use of less radiogenic Australian Pb in alkylPb additives) and then, during its phasing out and the adoption of unleaded petrol, complete by 2000 A.D., the subsequent increase in both Sb/Pb and 206Pb/207Pb ratios. The extent of the 20th century maximum anthropogenic enrichment of Sb and Pb, relative to the natural Sc-normalised levels of the Upper Continental Crust, was similar at approximately 50- to 100-fold. Prior to 1800 A.D., the influence of metallurgical activities on Sb and Pb concentrations in the peat cores during both the Mediaeval and Roman/pre-Roman periods was discernible, small Sb and Pb peaks during the latter appearing attributable, on the basis of Pb isotopic composition, to the mining/smelting of Pb ores indigenous to Britain.