Glaciochemical Records from the Saint Elias Mountains, Yukon, Canada Kaplan B
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Plate Tectonics, Volcanoes, and Earthquakes / Edited by John P
ISBN 978-1-61530-106-5 Published in 2011 by Britannica Educational Publishing (a trademark of Encyclopædia Britannica, Inc.) in association with Rosen Educational Services, LLC 29 East 21st Street, New York, NY 10010. Copyright © 2011 Encyclopædia Britannica, Inc. Britannica, Encyclopædia Britannica, and the Thistle logo are registered trademarks of Encyclopædia Britannica, Inc. All rights reserved. Rosen Educational Services materials copyright © 2011 Rosen Educational Services, LLC. All rights reserved. Distributed exclusively by Rosen Educational Services. For a listing of additional Britannica Educational Publishing titles, call toll free (800) 237-9932. First Edition Britannica Educational Publishing Michael I. Levy: Executive Editor J. E. Luebering: Senior Manager Marilyn L. Barton: Senior Coordinator, Production Control Steven Bosco: Director, Editorial Technologies Lisa S. Braucher: Senior Producer and Data Editor Yvette Charboneau: Senior Copy Editor Kathy Nakamura: Manager, Media Acquisition John P. Rafferty: Associate Editor, Earth Sciences Rosen Educational Services Alexandra Hanson-Harding: Editor Nelson Sá: Art Director Cindy Reiman: Photography Manager Nicole Russo: Designer Matthew Cauli: Cover Design Introduction by Therese Shea Library of Congress Cataloging-in-Publication Data Plate tectonics, volcanoes, and earthquakes / edited by John P. Rafferty. p. cm.—(Dynamic Earth) “In association with Britannica Educational Publishing, Rosen Educational Services.” Includes index. ISBN 978-1-61530-187-4 ( eBook) 1. Plate tectonics. -
Yukon College Student Survey Results
Yukon College Student Survey Results 2014-15 Dawn Macdonald Institutional Research and Planning Officer December 24, 2014 Yukon College Student Survey Results: 2014-15 TABLE OF CONTENTS HIGHLIGHTS ...................................................................................................................................................... 3 PURPOSE AND METHODS ............................................................................................................................. 5 RESULTS .............................................................................................................................................................. 6 STUDENT SATISFACTION ............................................................................................................................................ 6 More than nine out of ten would recommend their program or courses .................................... 6 Nearly everyone is satisfied with the quality of instruction ............................................................. 7 More than nine out of ten are satisfied with course content ........................................................... 7 Nine out of ten are satisfied with support services ............................................................................. 8 Nine out of ten are satisfied with program advising and library resources ............................... 9 Satisfaction with spaces for group work lags behind satisfaction with social spaces and study spaces ................................................................................................................................................... -
A Winter Forecasting Handbook Winter Storm Information That Is Useful to the Public
A Winter Forecasting Handbook Winter storm information that is useful to the public: 1) The time of onset of dangerous winter weather conditions 2) The time that dangerous winter weather conditions will abate 3) The type of winter weather to be expected: a) Snow b) Sleet c) Freezing rain d) Transitions between these three 7) The intensity of the precipitation 8) The total amount of precipitation that will accumulate 9) The temperatures during the storm (particularly if they are dangerously low) 7) The winds and wind chill temperature (particularly if winds cause blizzard conditions where visibility is reduced). 8) The uncertainty in the forecast. Some problems facing meteorologists: Winter precipitation occurs on the mesoscale The type and intensity of winter precipitation varies over short distances. Forecast products are not well tailored to winter Subtle features, such as variations in the wet bulb temperature, orography, urban heat islands, warm layers aloft, dry layers, small variations in cyclone track, surface temperature, and others all can influence the severity and character of a winter storm event. FORECASTING WINTER WEATHER Important factors: 1. Forcing a) Frontal forcing (at surface and aloft) b) Jetstream forcing c) Location where forcing will occur 2. Quantitative precipitation forecasts from models 3. Thermal structure where forcing and precipitation are expected 4. Moisture distribution in region where forcing and precipitation are expected. 5. Consideration of microphysical processes Forecasting winter precipitation in 0-48 hour time range: You must have a good understanding of the current state of the Atmosphere BEFORE you try to forecast a future state! 1. Examine current data to identify positions of cyclones and anticyclones and the location and types of fronts. -
Extending the Late Holocene White River Ash Distribution, Northwestern Canada STEPHEN D
ARCTIC VOL. 54, NO. 2 (JUNE 2001) P. 157– 161 Extending the Late Holocene White River Ash Distribution, Northwestern Canada STEPHEN D. ROBINSON1 (Received 30 May 2000; accepted in revised form 25 September 2000) ABSTRACT. Peatlands are a particularly good medium for trapping and preserving tephra, as their surfaces are wet and well vegetated. The extent of tephra-depositing events can often be greatly expanded through the observation of ash in peatlands. This paper uses the presence of the White River tephra layer (1200 B.P.) in peatlands to extend the known distribution of this late Holocene tephra into the Mackenzie Valley, northwestern Canada. The ash has been noted almost to the western shore of Great Slave Lake, over 1300 km from the source in southeastern Alaska. This new distribution covers approximately 540000 km2 with a tephra volume of 27 km3. The short time span and constrained timing of volcanic ash deposition, combined with unique physical and chemical parameters, make tephra layers ideal for use as chronostratigraphic markers. Key words: chronostratigraphy, Mackenzie Valley, peatlands, White River ash RÉSUMÉ. Les tourbières constituent un milieu particulièrement approprié au piégeage et à la conservation de téphra, en raison de l’humidité et de l’abondance de végétation qui règnent en surface. L’observation des cendres contenues dans les tourbières permet souvent d’élargir notablement les limites spatiales connues des épisodes de dépôts de téphra. Cet article recourt à la présence de la couche de téphra de la rivière White (1200 BP) dans les tourbières pour agrandir la distribution connue de ce téphra datant de l’Holocène supérieur dans la vallée du Mackenzie, située dans le Nord-Ouest canadien. -
Geographic Patterns in Morphometric and Genetic Variation for Coyote Populations with Emphasis on Southeastern Coyotes
Received: 19 March 2018 | Revised: 2 December 2018 | Accepted: 20 December 2018 DOI: 10.1002/ece3.4966 ORIGINAL RESEARCH Geographic patterns in morphometric and genetic variation for coyote populations with emphasis on southeastern coyotes Joseph W. Hinton1 | Elizabeth Heppenheimer2 | Kyla M. West3 | Danny Caudill4 | Melissa L. Karlin5 | John C. Kilgo6 | John Joseph Mayer7 | Karl V. Miller1 | Margaret Walch8 | Bridgett vonHoldt2 | Michael J. Chamberlain1 1Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Abstract Georgia Prior to 1900, coyotes (Canis latrans) were restricted to the western and central re- 2 Department of Ecology and Evolutionary gions of North America, but by the early 2000s, coyotes became ubiquitous through- Biology, Princeton University, Princeton, New Jersey out the eastern United States. Information regarding morphological and genetic 3Tacoma, Washington structure of coyote populations in the southeastern United States is limited, and 4 Florida Fish and Wildlife Conservation where data exist, they are rarely compared to those from other regions of North Commission, Gainesville, Florida America. We assessed geographic patterns in morphology and genetics of coyotes 5Department of Physics and Environmental Sciences, St. Mary’s University, San Antonio, with special consideration of coyotes in the southeastern United States. Mean body Texas mass of coyote populations increased along a west‐to‐east gradient, with southeast- 6United States Department of Agriculture, Forest Service Southern ern coyotes being intermediate to western and northeastern coyotes. Similarly, prin- Research Station, New Ellenton, South cipal component analysis of body mass and linear body measurements suggested Carolina that southeastern coyotes were intermediate to western and northeastern coyotes in 7United States Department of Energy, Environmental Sciences, and body size but exhibited shorter tails and ears from other populations. -
The Observation of the Lightning Induced Variations in Atmospheric Ions
XV International Conference on Atmospheric Electricity, 15-20 June 2014, Norman, Oklahoma, U.S.A. The Observation of the Lightning Induced Variations in Atmospheric Ions Xuemeng Chen1,*, Hanna E. Manninen1,2, Pasi Aalto1, Petri Keronen1, Antti Mäkelä3, Jussi Paatero3, Tuukka Petäjä1 and Markku Kulmala1 1. Department of Physics, University of Helsinki, Helsinki, Finland 2. Institute of Physics, University of Tartu, Estonia 3. Finnish Meteorological Institute, Helsinki, Finland ABSTRACT: Variations in atmospheric ion concentration were studied in a boreal forest in Finland, with emphasis on the effect of lightning. In general, changes in ion concentrations have diurnal and seasonal patterns. Distinct features were found in ions of different size ranges, namely small ions (0.8 – 1.7 nm) and intermediate ions (1.7 – 7 nm). Preliminary results on two case studies of lightning effect are present, one with rain effect and the other not. Bursts in the concentrations of small ions and intermediate ions were observed in both cases. However, different trends in trace gases were observed for the two cases. Further investigation is needed to reveal the nature of lightning ions and the mechanism in their formation. The work is under progress. INTRODUCTION Atmospheric ions, or air ions, refer to electric charge carriers present in the atmosphere. Distinct features exist in their chemical composition, mass, size as well as number of carried charges. According to Tammet [1998], atmospheric ions can be classified into small or cluster ions, intermediate ions, and large ions based on their mobility (Z) in air, being Z > 0.5 cm2V-1s-1, 0.5 cm2V-1s-1 ≤ Z ≥ 0.03 cm2V-1s-1 and Z< 0.03 cm2V-1s-1, respectively. -
The Error Is the Feature: How to Forecast Lightning Using a Model Prediction Error [Applied Data Science Track, Category Evidential]
The Error is the Feature: How to Forecast Lightning using a Model Prediction Error [Applied Data Science Track, Category Evidential] Christian Schön Jens Dittrich Richard Müller Saarland Informatics Campus Saarland Informatics Campus German Meteorological Service Big Data Analytics Group Big Data Analytics Group Offenbach, Germany ABSTRACT ACM Reference Format: Despite the progress within the last decades, weather forecasting Christian Schön, Jens Dittrich, and Richard Müller. 2019. The Error is the is still a challenging and computationally expensive task. Current Feature: How to Forecast Lightning using a Model Prediction Error: [Ap- plied Data Science Track, Category Evidential]. In Proceedings of 25th ACM satellite-based approaches to predict thunderstorms are usually SIGKDD Conference on Knowledge Discovery and Data Mining (KDD ’19). based on the analysis of the observed brightness temperatures in ACM, New York, NY, USA, 10 pages. different spectral channels and emit a warning if a critical threshold is reached. Recent progress in data science however demonstrates 1 INTRODUCTION that machine learning can be successfully applied to many research fields in science, especially in areas dealing with large datasets. Weather forecasting is a very complex and challenging task requir- We therefore present a new approach to the problem of predicting ing extremely complex models running on large supercomputers. thunderstorms based on machine learning. The core idea of our Besides delivering forecasts for variables such as the temperature, work is to use the error of two-dimensional optical flow algorithms one key task for meteorological services is the detection and pre- applied to images of meteorological satellites as a feature for ma- diction of severe weather conditions. -
2020 January Scree
the SCREE Mountaineering Club of Alaska January 2020 Volume 63, Number 1 Contents Mount Anno Domini Peak 2330 and Far Out Peak Devils Paw North Taku Tower Randoism via Rosie’s Roost "The greatest danger for Berlin Wall most of us is not that our aim is too high and we Katmai and the Valley of Ten Thousand Smokes miss it, but that it is too Peak of the Month: Old Snowy low and we reach it." – Michelangelo JANUARY MEETING: Wednesday, January 8, at 6:30 p.m. Luc Mehl will give the presentation. The Mountaineering Club of Alaska www.mtnclubak.org "To maintain, promote, and perpetuate the association of persons who are interested in promoting, sponsoring, im- proving, stimulating, and contributing to the exercise of skill and safety in the Art and Science of Mountaineering." This issue brought to you by: Editor—Steve Gruhn assisted by Dawn Munroe Hut Needs and Notes Cover Photo If you are headed to one of the MCA huts, please consult the Hut Gabe Hayden high on Devils Paw. Inventory and Needs on the website (http://www.mtnclubak.org/ Photo by Brette Harrington index.cfm/Huts/Hut-Inventory-and-Needs) or Greg Bragiel, MCA Huts Committee Chairman, at either [email protected] or (907) 350-5146 to see what needs to be taken to the huts or repaired. All JANUARY MEETING huts have tools and materials so that anyone can make basic re- Wednesday, January 8, at 6:30 p.m. at the BP Energy Center at pairs. Hutmeisters are needed for each hut: If you have a favorite 1014 Energy Court in Anchorage. -
The Alaska-Yukon Region of the Circumboreal Vegetation Map (CBVM)
CAFF Strategy Series Report September 2015 The Alaska-Yukon Region of the Circumboreal Vegetation Map (CBVM) ARCTIC COUNCIL Acknowledgements CAFF Designated Agencies: • Norwegian Environment Agency, Trondheim, Norway • Environment Canada, Ottawa, Canada • Faroese Museum of Natural History, Tórshavn, Faroe Islands (Kingdom of Denmark) • Finnish Ministry of the Environment, Helsinki, Finland • Icelandic Institute of Natural History, Reykjavik, Iceland • Ministry of Foreign Affairs, Greenland • Russian Federation Ministry of Natural Resources, Moscow, Russia • Swedish Environmental Protection Agency, Stockholm, Sweden • United States Department of the Interior, Fish and Wildlife Service, Anchorage, Alaska CAFF Permanent Participant Organizations: • Aleut International Association (AIA) • Arctic Athabaskan Council (AAC) • Gwich’in Council International (GCI) • Inuit Circumpolar Council (ICC) • Russian Indigenous Peoples of the North (RAIPON) • Saami Council This publication should be cited as: Jorgensen, T. and D. Meidinger. 2015. The Alaska Yukon Region of the Circumboreal Vegetation map (CBVM). CAFF Strategies Series Report. Conservation of Arctic Flora and Fauna, Akureyri, Iceland. ISBN: 978- 9935-431-48-6 Cover photo: Photo: George Spade/Shutterstock.com Back cover: Photo: Doug Lemke/Shutterstock.com Design and layout: Courtney Price For more information please contact: CAFF International Secretariat Borgir, Nordurslod 600 Akureyri, Iceland Phone: +354 462-3350 Fax: +354 462-3390 Email: [email protected] Internet: www.caff.is CAFF Designated -
Climatic Information of Western Sahel F
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Clim. Past Discuss., 10, 3877–3900, 2014 www.clim-past-discuss.net/10/3877/2014/ doi:10.5194/cpd-10-3877-2014 CPD © Author(s) 2014. CC Attribution 3.0 License. 10, 3877–3900, 2014 This discussion paper is/has been under review for the journal Climate of the Past (CP). Climatic information Please refer to the corresponding final paper in CP if available. of Western Sahel V. Millán and Climatic information of Western Sahel F. S. Rodrigo (1535–1793 AD) in original documentary sources Title Page Abstract Introduction V. Millán and F. S. Rodrigo Conclusions References Department of Applied Physics, University of Almería, Carretera de San Urbano, s/n, 04120, Almería, Spain Tables Figures Received: 11 September 2014 – Accepted: 12 September 2014 – Published: 26 September J I 2014 Correspondence to: F. S. Rodrigo ([email protected]) J I Published by Copernicus Publications on behalf of the European Geosciences Union. Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion 3877 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract CPD The Sahel is the semi-arid transition zone between arid Sahara and humid tropical Africa, extending approximately 10–20◦ N from Mauritania in the West to Sudan in the 10, 3877–3900, 2014 East. The African continent, one of the most vulnerable regions to climate change, 5 is subject to frequent droughts and famine. One climate challenge research is to iso- Climatic information late those aspects of climate variability that are natural from those that are related of Western Sahel to human influences. -
Marine Tephrochronology of the Mt
Quaternary Research 73 (2010) 277–292 Contents lists available at ScienceDirect Quaternary Research journal homepage: www.elsevier.com/locate/yqres Marine tephrochronology of the Mt. Edgecumbe Volcanic Field, Southeast Alaska, USA Jason A. Addison a,b,⁎, James E. Beget a,b, Thomas A. Ager c, Bruce P. Finney d a Alaska Quaternary Center and Department of Geology and Geophysics, University of Alaska Fairbanks, 900 Yukon Drive, PO Box 755780, Fairbanks, AK 99775-5780, USA b Alaska Quaternary Center, PO Box 755940, University of Alaska Fairbanks, Fairbanks, AK 99775-5940, USA c U.S. Geological Survey, Mail Stop 980, Box 25045, Denver Federal Center, Denver, CO 80225, USA d Department of Biological Sciences, Idaho State University, Pocatello, ID 83209-8007, USA article info abstract Article history: The Mt. Edgecumbe Volcanic Field (MEVF), located on Kruzof Island near Sitka Sound in southeast Alaska, Received 30 March 2009 experienced a large multiple-stage eruption during the last glacial maximum (LGM)–Holocene transition Available online 11 December 2009 that generated a regionally extensive series of compositionally similar rhyolite tephra horizons and a single well-dated dacite (MEd) tephra. Marine sediment cores collected from adjacent basins to the MEVF contain Keywords: both tephra-fall and pyroclastic flow deposits that consist primarily of rhyolitic tephra and a minor dacitic Tephra tephra unit. The recovered dacite tephra correlates with the MEd tephra, whereas many of the rhyolitic Alaska North Pacific Ocean tephras correlate with published MEVF rhyolites. Correlations were based on age constraints and major Cryptotephra oxide compositions of glass shards. In addition to LGM–Holocene macroscopic tephra units, four marine Mt. -
Forecasting of Thunderstorms in the Pre-Monsoon Season at Delhi
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Publications of the IAS Fellows Meteorol. Appl. 6, 29–38 (1999) Forecasting of thunderstorms in the pre-monsoon season at Delhi N Ravi1, U C Mohanty1, O P Madan1 and R K Paliwal2 1Centre for Atmospheric Sciences, Indian Institute of Technology, New Delhi 110 016, India 2National Centre for Medium Range Weather Forecasting, Mausam Bhavan Complex, Lodi Road, New Delhi 110 003, India Accurate prediction of thunderstorms during the pre-monsoon season (April–June) in India is essential for human activities such as construction, aviation and agriculture. Two objective forecasting methods are developed using data from May and June for 1985–89. The developed methods are tested with independent data sets of the recent years, namely May and June for the years 1994 and 1995. The first method is based on a graphical technique. Fifteen different types of stability index are used in combinations of different pairs. It is found that Showalter index versus Totals total index and Jefferson’s modified index versus George index can cluster cases of occurrence of thunderstorms mixed with a few cases of non-occurrence along a zone. The zones are demarcated and further sub-zones are created for clarity. The probability of occurrence/non-occurrence of thunderstorms in each sub-zone is then calculated. The second approach uses a multiple regression method to predict the occurrence/non- occurrence of thunderstorms. A total of 274 potential predictors are subjected to stepwise screening and nine significant predictors are selected to formulate a multiple regression equation that gives the forecast in probabilistic terms.