3,304 research outputs found
Temperature-index modeling of mass balance and runoff in the Valdez glacier catchment in 2012 and 2013
Thesis (M.S.) University of Alaska Fairbanks, 2015Glaciers play an important role in both storage and generation of runoff within individual watersheds. The Valdez Glacier catchment (342 km²), located in southern Alaska in the Chugach mountains off of Prince William Sound, is characterized by large annual volumes of rain- and snowfall. As Valdez Glacier and other glaciers within the catchment (comprising 58% of the catchment area) continue to melt in a warming climate, it is unclear how the runoff will be affected. Temperature-index modeling is one method used to estimate glacier mass balance and runoff in highly glacierized catchments, and may be suitable for predicting future runoff regimes. In this study, we used a combination of field measurements (air temperature, glacier mass balance, streamflow, and ground-penetrating radar (GPR)-derived snow water equivalent (SWE) from a parallel study) and modeled climate data (PRISM) to a) calibrate a temperature-index model to glacier mass balance in 2012; b) validate the model to laser altimetry; and c) calibrate a temperature-index model to runoff measurements in fall of 2012 and in spring, summer and fall of 2013. We calibrated the snow-radiation coefficient (r_snow), ice-radiation coefficient (r_ice), and melt factor (MF) of the temperature-index model to glacier mass balance measurements from 2012. Using the calibrated- r_snow, r_ice, and MF (i.e. r_snow, r_ice, and MF = 0.20, 0.50 and 4.0, respectively), we calculated 2012 annual glacier mass balance (Ba) at 0.05 ± 0.49 meters water equivalent (m w.eq.). We next validated the model to 2012 laser altimetry annual glacier mass balance estimates (Ba = 0.20 ± 0.6 m w.eq.). We then modeled glacier mass balance in 2013 using r_snow, r_ice, and MF from the 2012 calibration. The model underestimated summer glacier mass balance in 2013, resulting in annual glacier mass balance (Ba = 0.55 m w.eq.) that did not fall within the 2013 laser altimetry annual balance estimate (Ba = -1.15 +0.29/-0.30 m w.eq.). We therefore re-calibrated MF to 2013 laser altimetry measurements, resulting in an annual glacier mass balance (Ba) of -1.10 ± 0.49 m w. eq. We next calibrated the storage constants of the runoff model to hydrographs from mid-September until mid-October 2012, and from May until October 2013, with r_snow, r_ice, and MF set to values from the 2012 glacier mass balance calibration. Total modeled runoff in mid- September until mid-October 2012 was within 3% of measured runoff (E- and lnE- were 0.54 and 0.76, respectively). Modeled runoff in 2013 was calculated to within 5% of 2013 runoff measurements (E- and lnE-values of 0.79 and 0.70, respectively). We next modeled runoff in 2013 using MF from the 2013 glacier mass balance calibration to laser altimetry (i.e. MF = 7.0). The fit of 2013 modeled to measured runoff was reduced (E- and lnE- values of 0.44 and 0.54, respectively), suggesting that additional glacier mass balance measurements are necessary in 2013 in order to properly calibrate the model. Results indicate that glacier melt parameters likely vary inter-annually. Therefore, the temperature-index model is capable of modeling both glacier melt and runoff in a maritime catchment, provided that ablation stake, air temperature, precipitation, and streamflow measurements are available for the simulation period
Realizing Health Reform's Potential: Small Businesses and the Affordable Care Act of 2010
Examines current coverage of workers in small firms, insurers' administrative costs, and healthcare reform provisions such as small-business tax credits to offset premiums and exemption from shared responsibility payments and the estimated impact of each
The 2008 Presidential Candidates' Health Reform Proposals: Choices for America
Looks at key differences in the 2008 presidential candidates' health insurance reforms and evaluates them against the Commonwealth Fund Commission on a High Performance Health System's principles. Estimates each plan's impact on the number of uninsured
Squeezed: Why Rising Exposure to Health Care Costs Threatens the Health and Financial Well-Being of American Families
Examines U.S. healthcare costs compared with other industrialized countries, individual health insurance coverage, individual market regulations, and the impact of high deductible plans on the health of individuals with chronic disease
Gaps in Health Insurance: An All-American Problem
Presents findings from a survey that examines health insurance coverage, rising healthcare costs, and the health and financial consequences to families that experience breaks in insurance
Role of Social Media in Adolescent-Parent Relationships Among At-Risk Youths
This study aimed to understand the role of adolescent and parent social media use on adolescents reported at-risk behaviors, as well as the role of social media among at-risk youths and their parents. Semi-structured interviews, based on interpretive phenomenological analysis, were utilized with six pairs of individuals resulting in 12 total participants. Each pair consisted of an adolescent between the ages of 13 and 17 along with their parent. Data analysis resulted in three themes: encountering negativity on social media did not refrain the adolescent from social media usage, misunderstanding of the parent regarding social media and technology caused challenges in parental monitoring, and the quality of time spent together differed in the perception of the adolescent participants and parent participants. The findings of this study suggest that even though participant pairs reported encountering negativity on social media, they continue to use social media, and parent participants are unaware of the amount of time their adolescent spends on social media, which could be contributed to the lack of quality time they spend with one another. The findings of this research add to the current literature regarding social media and the impact it has on the parent-adolescent relationship among at-risk youth
Health Coverage for Aging Baby Boomers: Findings From The Commonwealth Fund Survey of Older Adults
Examines healthcare quality and access by baby boomers in working families. Offers recommendations for expanding coverage, including options for savings accounts and early participation in Medicare
The Health Insurance Provisions of the 2009 Congressional Health Reform Bills: Implications for Coverage, Affordability, and Costs
Analyzes the House and Senate healthcare reform bills for the number of people likely to gain coverage and the implications for federal financing, families' insurance premium and out-of-pocket costs, employers, and the potential for price competition
Driving in Early-Stage Alzheimer’s Disease: An Integrative Review of the Literature
One of the most difficult decisions for individuals with Alzheimer’s disease (AD) is when to stop driving. Because driving is a fundamental activity linked to socialization, independent functioning, and wellbeing, making the decision to stop driving is not easy. Cognitive decline in older adults can lead to getting lost while driving, difficulty detecting and avoiding hazards, as well as increased errors while driving due to compromised judgment and difficulty in making decisions. The purpose of the current literature review was to synthesize evidence regarding how individuals with early-stage AD, their families, and providers make determinations about driving safety, interventions to increase driving safety, and methods to assist cessation and coping for individuals with early-stage AD. The evidence shows that changes in driving ability start early and progress throughout the trajectory of AD. Some individuals with mild cognitive impairment or early-stage AD may be safe to drive for a period of time. Support groups aimed at helping with the transition have been shown to be helpful for individuals who stop driving. Research and practice must support interventions to help individuals maintain safety while driving, as well as cope with driving cessation
My Sister, Our Stories: Exploring the Lived Experience of School Leavers through Narrative and Poetics
The purpose of this study was to explore the educational experiences of two adult female siblings who are both school leavers. Through the use of thematic narrative analysis, sibling narratives and poetic re-presentations, their stories were developed. These stories represent the participants’ experiences of prior schooling and their current commitments to education. While each story conveyed a profound similarity in terms of prior schooling, contrasting narratives were illustrated through description of transitional moments and sibling relationship. The analysis also explored the intersections of race, gender,and social class within educative moments of the life experiences of the participants
- …