Eclipse Ice Core Accumulation and Stable Isotope Variability as an Indicator of North Pacific Climate

The high accumulation rate and negligible amount of melt at Eclipse Icefield (3017 m) in the Saint Elias Range of Yukon, Canada, allows for the preservation of a high-resolution isotopic and glaciochemical records valuable for reconstruction of climatic variables. Each of the three Eclipse ice cores have a well-constrained depth–age scale with dozens of reference horizons over the twentieth century that permits an exceptional level of confi- dence in the results of the current calibration exercise. Stacked time series of accumulation and stable isotopes were divided into cold and warm seasons and seasons of extreme high and extreme low accumulation and stable isotope values (eight groups). For each group, season-averaged composites of 500-hPa geopotential height grids, and the individual seasons that constitute them, were analyzed to elucidate common anomalous flow patterns. This analysis shows that the most fractionated isotopes and lowest accumulation cold seasons reflect a more zonal height pattern in the North Pacific associated with negative Pacific–North American (PNA) and Pacific decadal oscillation (PDO) indices. Conversely, the least fractionated isotopes and highest accumulation cold seasons are associated with a positive PNA pattern. Although only a maximum of approximately 20% of the total number of accumulation and stable isotope seasons exhibit a relatively consistent relationship with 500-hPa geopotential height patterns, these results support the hypothesis that the most extreme accumulation and extreme isotope cold-season values in the Saint Elias Mountains are related to consistent atmospheric circulation and oceanic sea surface temperature patterns

The climatological rise in winter temperature- and dewpoint-based thaw events and their impact on snow depth on Mount Washington, New Hampshire

Author Posting. © American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Applied Meteorology and Climatology 60(9), (2021): 1361–1370, https://doi.org/10.1175/JAMC-D-20-0254.1.We analyze how winter thaw events (TE; T > 0°C) are changing on the summit of Mount Washington, New Hampshire, using three metrics: the number of TE, number of thaw hours, and number of thaw degree-hours for temperature and dewpoint for winters from 1935/36 to 2019/20. The impact of temperature-only TE and dewpoint TE on snow depth are compared to quantify the different impacts of sensible-only heating and sensible-and-latent heating, respectively. Results reveal that temperature and dewpoint TE for all metrics increased at a statistically significant rate (p < 0.05) over the full time periods studied for temperature (1935/36–2019/20) and dewpoint (1939/40–2019/20). Notably, around 2000/01, the positive trends increased for most variables, including dewpoint-thaw degree-hours that increased by 82.11 degree-hours decade−1 during 2000–20, which is approximately 5 times as faster as the 1939–2020 rate of 17.70 degree-hours decade−1. Furthermore, a clear upward shift occurred around 1990 in the lowest winter values of thaw hours and thaw degree-hours—winters now have a higher baseline amount of thaw than before 1990. Snow-depth loss during dewpoint TE (0.36 cm h−1) occurred more than 2 times as fast as temperature-only TE (0.14 cm h−1). With winters projected to warm throughout the twenty-first century in the northeastern United States, it is expected that the trends in winter thaw events, and the sensible and latent energy that they bring, will continue to rise and lead to more frequent winter flooding, fewer days of good quality snow for winter recreation, and changes in ecosystem function

Climate Change in the Piscataqua/Great Bay Region: Past, Present, and Future

Earth ’s climate changes. It always has and always will. However, an extensive body of scientific evidence indicates that human activities are now a significant force driving change in the Earth’s climate system. This report describes how the climate of the Piscataqua/Great Bay region of coastal New Hampshire in the United States has changed over the past century and how the future climate of the region will be affected by human activities that are warming the planet. Overall, the region has been getting warmer and wetter over the last century, and the rate of change has increased over the last four decades. To generate future climate projections for the region, simulated temperature and precipitation from four general circulation models were fitted to local, long-term weather observations. Unknowns regarding future fossil fuel consumption were accounted for by using two future emissions scenarios. As greenhouse gases continue to accumulate in the atmosphere, temperatures will rise, extreme heat days are projected to occur more often and will be hotter, extreme cold temperatures are projected to occur less often, and cold days will be warmer.. Annual average precipitation is projected to increase 12 to 17% by end-of-century and the region can expect to see more extreme precipitation events in the future. Tidal gauge data indicates relative sea level at Portsmouth has risen 0.7 inches per decade over the past eight decades. Projected sea level rise of 1.7 to 6.3 feet will result in higher storm surges and more frequent flooding in coastal New Hampshire

Ice Layers as an Indicator of Summer Warmth and Atmospheric Blocking in Alaska

Samples were collected from a snow pit and shallow urn core near Kahiltna Pass (2970 m a.s.l.), Denali National Park, Alaska, USA, in May 2008. The record spans autumn 2003 to spring 2008 and reveals clusters of ice layers interpreted as summertime intervals of above-freezing temperatures. High correlation coefficients (0.75-1.00) between annual ice-layer thickness and regional summertime station temperatures for 4 years (n=4) indicate ice-layer thickness is a good proxy for mean and extreme summertime temperatures across Alaska, at least over the short period of record. A Rex-block (aka high-over-low) pattern, a downstream trough over Hudson Bay, Canada, and an upstream trough over eastern Siberia occurred during the three melting events that lasted at least 2 weeks. About half of all shorter melting events were associated with a cut-off low traversing the Gulf of Alaska. We hypothesize that a surface-to-bedrock core extracted from this location would provide a high-quality record of summer temperature and atmospheric blocking variability for the last several hundred years

Sexuality and intimacy among people living with serious mental illnesses: Factors contributing to sexual activity

OBJECTIVE: Limited research has focused on sexuality for those diagnosed with a severe mental illness. We aimed to extend existing work by exploring relationships between mastery (perception of control of one's life and future), sexual self-esteem (perceptions of one's capacity to engage in healthy sexual behavior), sexual attitudes (permissive ideas about sexuality), and perceived importance of relationships/sexuality and number of sexual partners. METHOD: A secondary analysis of survey data from adult participants living with a severe mental illness (N = 401) in the Indiana Mental Health Services and HIV-Risk Study (Perry & Wright, 2006) was conducted. Analysis of covariance (controlling for marital status) compared those with 0 partners, 1 partner, or multiple partners over the past 3 months on the dependent variables of mastery, sexual self-esteem, sexual attitudes, and perceived importance. RESULTS: Participants with more permissive attitudes, greater perceived importance, and higher mastery were more likely to be sexually active with multiple partners. Self-esteem did not differentiate groups. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Given the key role of sexual satisfaction in quality of life and the high rates of sexual risk behavior in this population, it is important that clinicians systematically assess mastery, perceived importance, and attitudes about sexuality when working with consumers diagnosed with a severe mental illness. Individually tailoring existing interventions on the basis of consumers' levels of mastery, related to self-efficacy for implementing changes in life, could improve long-term outcomes for these programs. Future research should examine other constructs that may account for more variance in sexual activity, such as perceptions of risk, intentions for sexual safety, or romantic relationship functioning

Digital droplet PCR and IDAA for the detection of CRISPR indel edits in the malaria species <i>Anopheles stephensi</i>

CRISPR/Cas9 technology is a powerful tool for the design of gene-drive systems to control and/or modify mosquito vector populations; however, CRISPR/Cas9-mediated nonhomologous end joining mutations can have an important impact on generating alleles resistant to the drive and thus on drive efficiency. We demonstrate and compare the insertions or deletions (indels) detection capabilities of two techniques in the malaria vector mosquito Anopheles stephensi: Indel Detection by Amplicon Analysis (IDAA™) and Droplet Digital™ PCR (ddPCR™). Both techniques showed accuracy and reproducibility for indel frequencies across mosquito samples containing different ratios of indels of various sizes. Moreover, these techniques have advantages that make them potentially better suited for high-throughput nonhomologous end joining analysis in cage trials and contained field testing of gene-drive mosquitoes

Eclipse Ice Core Accumulation and Stable Isotope Variability as an Indicator of North Pacific Climate

The high accumulation rate and negligible amount of melt at Eclipse Icefield (3017 m) in the Saint Elias Range of Yukon, Canada, allows for the preservation of a high-resolution isotopic and glaciochemical records valuable for reconstruction of climatic variables. Each of the three Eclipse ice cores have a well-constrained depth–age scale with dozens of reference horizons over the twentieth century that permits an exceptional level of confidence in the results of the current calibration exercise. Stacked time series of accumulation and stable isotopes were divided into cold and warm seasons and seasons of extreme high and extreme low accumulation and stable isotope values (eight groups). For each group, season-averaged composites of 500-hPa geopotential height grids, and the individual seasons that constitute them, were analyzed to elucidate common anomalous flow patterns. This analysis shows that the most fractionated isotopes and lowest accumulation cold seasons reflect a more zonal height pattern in the North Pacific associated with negative Pacific–North American (PNA) and Pacific decadal oscillation (PDO) indices. Conversely, the least fractionated isotopes and highest accumulation cold seasons are associated with a positive PNA pattern. Although only a maximum of approximately 20% of the total number of accumulation and stable isotope seasons exhibit a relatively consistent relationship with 500-hPa geopotential height patterns, these results support the hypothesis that the most extreme accumulation and extreme isotope cold-season values in the Saint Elias Mountains are related to consistent atmospheric circulation and oceanic sea surface temperature patterns.Keywords: Teleconnections, Pacific decadal oscillation, Pacific-North American pattern/oscillation, North Pacific Ocean, Paleoclimate, Climate variabilit

Interannual and interdecadal variability in the predominant Pacific region SST anomaly patterns and their impact on climate in the mid-Mississippi valley region

Previous research has demonstrated that Pacific Region SSTs and SST anomalies can be separated into seven general synoptic classifications (“clusters”) (A-G). Clusters B and G (C, D, and F) [A and E] were shown to be generally representative of La Niña (El Niño) [neutral] type SST distributions. Further, an analysis of the SST patterns from 1955 - 1993 demonstrated that clusters A - D were prominent from 1955-1977, while types E and F dominated the later period. Type G clusters were comparatively rare, but occurred during both periods. In retrospect, this shift during 1977 corresponds roughly with a change in phase of the Pacific Decadal Oscillation (PDO). After updating the analysis to include the 1994 to 2005 period, there was a corresponding change in the predominant SSTs associated with a change in phase of the PDO during 1999 and 2000. The results show that SST patterns did evolve from predominantly E and F-type anomalies in 1994 to A, B, D, and G-type anomalies through 2005. Thus, these results suggest that A through D-type (C, E, and F-type) SST clusters are characteristic of the negative (positive) phase of the PDO. Also, using a modified technique for generating phase diagrams, it is shown that there are interannual and interdecadal variations in the mid-Mississippi region monthly mean surface temperature and precipitation records that can be associated with the ENSO and PDO. Additionally, an analysis was performed to see if there was any statistical association between temperature and precipitation anomalies in the mid-Mississippi region and prolonged SST regimes. B, D and G anomalies were associated with warmer-than-normal conditions, while C and E type anomalies tended to be associated with cooler-than-normal conditions across the region. C, D, F, and G anomalies were associated with drier than normal conditions