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Evaluating Snow And Ice Cover In Tierra Del Fuego, Argentina, Zoe Pitman

Geosciences Undergraduate Honors Theses

Evaluating changes in snow and ice cover is an important field for studying climate change and its impacts. This evaluation is commonly done using remote sensing because of its ability to evaluate large areas. The purpose of this study is to determine the reliability of one remote sensing technology, the Moderate Resolution Imaging Spectroradiometer (MODIS), by comparing it to in-situ snow and climate data from the weather station at the Austral Center for Scientific Research (CADIC). Data was converted from daily to monthly averages and was sorted into a series of graphs to compare the two data sets. Correlations were …

A Workshop On Using Nasa Airs Data To Monitor Drought For The U.S. Drought Monitor, Alireza Farahmand,, Sharon Ray, Heidar Thrastarson, Stephen Licata, Stephanie Granger, Brian Fuchs

Drought Mitigation Center: Faculty Publications

Recent studies indicate that drought indicators based on near-surface air relative humidity (RH), air temperature (T), and air vapor pressure deficit (VPD), derived from the Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s Aqua satellite can detect the onset of drought earlier than other drought indicators, specifically standardized precipitation index (SPI), which is widely used for drought onset detection. A recent study showed that standardized relative humidity index (SRHI) can detect drought signals earlier than SPI (Farahmand et al. 2015). Relative humidity is a climate variable defined as the ratio of air vapor pressure to saturated vapor pressure. Precipitation and relative …

Evaluating Spatial-Temporal Patterns In Us Tornado Occurrence With Space Time Cube Analysis And Linear Kernel Density Estimation: 1950-2019, Darrell L. Wiser

Electronic Theses and Dissertations

This research estimated the spatial-temporal patterns of tornadoes in the continental United States from 1950-2019 using the National Weather Service Storm Prediction Center’s Severe Weather GIS (SVRGIS) database. This study employed Space-Time Cube Analysis and Linear Kernel Density (Kernel Density Linear Process, (KDLP)) rather than the standard Kernel Density Estimation (KDE) approach; to evaluate whether tornado hotspot locations and intensities shift over time.

The first phase of the study utilized KDLP to map changes in tornado hotspots and qualitatively assess decadal shifts in hotspot locations and intensities by occurrence and magnitude between decades using ArcGIS Pro and CrimeStat. Next an …

High-Tide Floods And Storm Surges During Atmospheric Rivers On The Us West Coast, Christopher G. Piecuch, Sloan Coats, Sönke Dangendorf, Felix W. Landerer, J. T. Reager, Philip R. Thompson, Thomas Wahl

CCPO Publications

Amospheric rivers (ARs) effect inland hydrological impacts related to extreme precipitation. However, little is known about the possible coastal hazards associated with these storms. Here we elucidate high-tide floods (HTFs) and storm surges during ARs through a statistical analysis of data from the US West Coast during 1980-2016. HTFs and landfalling ARs co-occur more often than expected from random chance. Between 10%-63% of HTFs coincide with landfalling ARs, depending on location. However, only 2%-15% of ARs coincide with HTFs, suggesting that ARs typically must co-occur with anomalously high tides or mean sea levels to cause HTFs. Storm surges during ARs …

The Multidisciplinary Enrichment Of Undergraduate Environmental Geology Students From International Summer Programs. Case Study: Summer 2019 3mugis, Russia, Ruslana Baker, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer

Publications and Research

Hosted by the People’s Friendly University of Russia (RUDN), the Modeling, Monitoring, and Managing of Urban Green Infrastructure (3MUGIS) summer program was organized by the collaboration of the New York City Urban Soil Institute (NYC-USI), City University of New York – Brooklyn College, and under the auspices of the International Union of Soil Sciences (IUSS). The program consisted of one-week lecture sessions and two-weeks of fieldwork across five bioclimatic zones, ranging from the sub-arctic tundra of the Kola Peninsula to the Southern Steps of Rostov, Black Sea. Faculty and guest lecturers included scientists with various expertise from Germany, USA, Russia, …

Corrigendum To "Upper Water Structure And Mixed Layer Depth In Tropical Waters: The Seats Station In The Northern South China Sea, Jen-Hua Tai, George T.F. Wong, Xiaoju Pan

OES Faculty Publications

No abstract provided.

Examining The Effects Of Greenland Ice Sheet Melting And Atlantic Meridional Shutdown On The Climate Of Scandinavia And The British Isles, Tyler Lemburg

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Earth’s climate has been rapidly changing over the last hundred years, and its global average temperature is rising. However, climate change is far more complicated than a simple increase in temperature. For example, it is theorized that certain regions of Earth, including Scandinavia and the British Isles, could actually become cooler through ongoing climate change processes. Two of these processes are Greenland Ice Sheet (GrIS) melting, and slowdown of the Atlantic Meridional Overturning Circulation (AMOC). This research examines if climate change, through GrIS melting and AMOC slowdown, could contribute to cooler, instead of warmer, temperatures in Scandinavia and the British …

A 12 Year Temperature And Wind Speed Climatology For The Marshall Field Site Near Boulder Colorado 2006-2018, John Nicholas Adrian, Scott Landolt

STAR Program Research Presentations

The Denver-Boulder region in Colorado is located on the border of two distinct weather regimes, the Rocky Mountains to the west and the Great Plains to the east. This region experiences inclement and sometimes unpredictable weather events, which can be accompanied by changes in temperatures and wind speed. To better understand the climate for the region, nearly 12 years of temperature and wind speed data from the Marshall Field Site were analyzed to assess changes in these parameters over time. Methods: Temperature recordings were primarily taken from a CS-500L probe, with data gaps filled in from a Lufft WS600 and …

Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Climate variability at global and regional scales is escalating with increased atmospheric carbon and is expected to magnify the intensity and duration of meteorological extremes, especially droughts. From the many environmental stresses that diminish crop production (e.g., soil salinity, frost, soil erosion) drought is one of the most prevalent. This study focuses on the sensitivity of three key crops produced in the northwestern United States to climatological anomalies, while controlling for attribution using anomalies in price. The study differs from similar studies in that we focus on variability in production which captures both yield (tonnes/ha) and cropping area (ha), as …

Upper Water Structure And Mixed Layer Depth In Tropical Waters: The Seats Station In The Northern South China Sea, Jen-Hua Tai, George T. F. Wong, Xiaoju Pan

OES Faculty Publications

The variability of the upper water hydrographic structure, the efficacy of the different schemes for estimating the mixed layer depth (MLD), the inter-comparability estimation of the MLDs and diurnal and intra-annual MLD climatology in the tropical waters in the northern South China Sea were accessed in 702 depth-profiles of potential temperature (θ) and salinity collected in 64 cruises between 17.5 and 18.5°N and 115.3 and 116.3°E from 1997 to 2013. The hydrographic structure may be subdivided into three principal types: the classical type, with quasi-isopycnal surface mixed layer followed by an abrupt increase in the depth-gradient in θ and potential …

Interferometric Swath Processing Of Cryosat Data For Glacial Ice Topography, L. Gray, D. Burgess, L. Copland, R. Cullen, N. Galin, R. Hawley, V. Helm

Dartmouth Scholarship

We have derived digital elevation models (DEMs) over the western part of the Devon Ice Cap in Nunavut, Canada, using "swath processing" of interferometric data collected by Cryosat between February 2011 and January 2012. With the standard ESA (European Space Agency) SARIn (synthetic aperture radar interferometry) level 2 (L2) data product, the interferometric mode is used to map the cross-track position and elevation of the "point-of-closest-approach" (POCA) in sloping glacial terrain. However, in this work we explore the extent to which the phase of the returns in the intermediate L1b product can also be used to map the heights of …

Transition In The Fractal Geometry Of Arctic Melt Ponds, C. Hohenegger, B. Alali, K. R. Steffen, D. K. Perovich, K. M. Golden

Dartmouth Scholarship

During the Arctic melt season, the sea ice surface undergoes a remarkable transformation from vast expanses of snow covered ice to complex mosaics of ice and melt ponds. Sea ice albedo, a key parameter in climate modeling, is determined by the complex evolution of melt pond configurations. In fact, ice–albedo feedback has played a major role in the recent declines of the summer Arctic sea ice pack. However, understanding melt pond evolution remains a significant challenge to improving climate projections. By analyzing area–perimeter data from hundreds of thousands of melt ponds, we find here an unexpected separation of scales, where …

Variations In Climatic Parameters And Food Crop Yields: Implications On Food Security In Benue State, Nigeria., Emmanuel Adamgbe, Fanan Ujoh

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Agricultural production in Nigeria like in other developing countries is highly vulnerable to variations in climatic parameters which may have inverse or direct effect on the performance of food crops. This paper examines the patterns and trends of the variations in the climatic parameters and the implications of such variations on efficient yield rates of some food crops in Benue State using data on climatic variables (rainfall, temperature, sunshine) and the yield of some crops per hectare for 25 years (1986-2010). Data on the climatic variables were collected from the Nigerian Meteorological Agency, AirForce Base, Makurdi while the data on …

Rainfall Variability And Crop Zones Classification For The Federal Capital Territory, Nigeria, Shaibu M. Hassan Phd

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

This study aims at analyzing agro-climatological parameters and establishing a link between some selected agro-climatological indices and sustainability of agricultural production in the Federal Capital Territory (FCT). Two sets of data, climatic and crop yield data were collected and subjected to various agro-climatological analyses. Agro-climatological analyses include the derivation of Onset, Cessation and Length of Rainy Season (LRS), Seasonality Index, Drought Index and Precipitation Periodicity Index. The statistical analyses include monthly and annual means, deviation from the mean, trend line. The result of moisture index in line with crops optimum moisture requirement was used to classify the Territory into agro-climatic …

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopologues: 1. Comparison Between Models And Observations, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Debra Wunch, Vanessa Sherlock, Nicholas Deutscher, David Griffith, Paul O. Wennberg, Kimberly Strong, Dan Smale, Emmanuel Mahieu, Sabine Barthlott, Frank Hase, Omaira García, Justus Notholt, Thorsten Warneke, Geoffrey Toon, David Sayres, Sandrine Bony, Jeonghoon Lee, Derek Brown, Ryu Uemura, Christophe Sturm

Chemistry & Biochemistry Faculty Publications

The goal of this study is to determine how H₂O and HDO measurements in water vapor can be used to detect and diagnose biases in the representation of processes controlling tropospheric humidity in atmospheric general circulation models (GCMs). We analyze a large number of isotopic data sets (four satellite, sixteen ground-based remote-sensing, five surface in situ and three aircraft data sets) that are sensitive to different altitudes throughout the free troposphere. Despite significant differences between data sets, we identify some observed HDO/H₂O characteristics that are robust across data sets and that can be used to evaluate …

Process-Evaluation Of Tropospheric Humidity Simulated By General Circulation Models Using Water Vapor Isotopic Observations: 2. Using Isotopic Diagnostics To Understand The Mid And Upper Tropospheric Moist Bias In The Tropics And Subtropics, Camille Risi, David Noone, John Worden, Christian Frankenberg, Gabriele Stiller, Michael Kiefer, Bernd Funke, Kaley Walker, Peter Bernath, Matthias Schneider, Sandrine Bony, Jeonghoon Lee, Derek Brown, Christophe Sturm

Chemistry & Biochemistry Faculty Publications

Evaluating the representation of processes controlling tropical and subtropical tropospheric relative humidity (RH) in atmospheric general circulation models (GCMs) is crucial to assess the credibility of predicted climate changes. GCMs have long exhibited a moist bias in the tropical and subtropical mid and upper troposphere, which could be due to the mis-representation of cloud processes or of the large-scale circulation, or to excessive diffusion during water vapor transport. The goal of this study is to use observations of the water vapor isotopic ratio to understand the cause of this bias. We compare the three-dimensional distribution of the water vapor isotopic …

Late 20th Century Hydrologic Change In Western North America: Regional Impacts And The Role Of Climate, Shaleen Jain

University of Maine Office of Research Administration: Grant Reports

Hydroclimatic variations and change directly impact the freshwater supplies in western North America. Streamflow in this region has shown increased variability of annual flow volumes and increasing synchroneity in the largest basins in the west towards the end of last century. As land-use change seems to play a lesser role, the PI will study the sensitivity of the western North American winter precipitation and related streamflow to El Nino-Southern Oscillation variations. The PI will use observations and multi-model ensemble integrations to study the decadal variations. The broader impact of this project will be an increase of the scientific knowledge required …

Constructing A Flash Flood Climatology Of The Appalachian Mountains: Comparison Of Eastern Kentucky And West Virginia Summer Time Rain Events, Jane Marie Wix

Mahurin Honors College Capstone Experience/Thesis Projects

The Appalachian Mountains are subject to flash floods due to interactions between complex terrain and frequent rainfall. Previous studies have shown that a number of environmental factors can trigger flash floods, which can leave behind a variety of outcomes. However, there is a lack of research concerning flash floods in the Appalachian region. This study addresses these concerns by examining summer (June-August) rainfall frequency and intensity in connection with flash floods in the Appalachian region of eastern Kentucky and West Virginia during 1995-2005. Flash floods were identified using the National Climatic Data Center’s (NCDC) Storm Database. Radar estimated rainfall data …

Collaborative Research: Chronology Of Ice Fluctuations In The South Shetland Islands Since The Last Glacial Maximum, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

This award supports a study of the timing of climate changes in the Southern Hemisphere with the goal of reconstructing former ice extent and fluctuations, as well as paleoclimate, along the key latitudinal transect from temperate Tierra del Fuego to the polar Antarctic Peninsula. Samples already in hand will allow the dating of ice fluctuations in the South Shetland Islands (SSI), a critical location where that transect crosses the Antarctic Convergence. Surprisingly little concrete evidence exists concerning former ice extent in the island chain. The results of this study will answer a number of basic questions regarding ice extent and …

Satellite Remote Sensing Of Glaciers And Ice Caps In Svalbard, Eurasian High Arctic, Gordon S. Hamilton

University of Maine Office of Research Administration: Grant Reports

Recent compilations of climate-related observations show that important changes are now underway in the High Arctic, probably as a response to anthropogenic greenhouse gas emissions over the last approximately 250 years. These changes include warming of the troposphere, reductions in sea ice cover, decreases in snow cover area, warming of tundra permafrost, and negative mass balances of glaciers and ice caps. In many instances, observations of change are relatively short in duration or sparse in spatial extent. The Principal Investigators will study glacier and ice cap variations over the approximately last 80 years and at a large scale on Svalbard. …

A New Mt. Logan Ice Core Record - Change In Climate And Chemistry Of The Atmosphere For The North Pacific, Paul Andrew Mayewski, Gregory Zielinski, Karl J. Kreutz, Andrei V. Kurbatov

University of Maine Office of Research Administration: Grant Reports

Mt. Logan, in the St. Elias Range, southeast Alaska, offers a unique opportunity for monitoring climate change and change in the atmospheric chemistry of the Gulf of Alaska and the North Pacific. In 1980, a 103-meter (M) ice core was recovered from Mt. Logan which spanned AD 1689-1980. It revealed well-defined annual layers, calibrated through the identification of radioactive bomb and volcanic horizons, allowing continuous, sub-seasonal sampling for stable isotopes and ion chemistry. The -29 degree C mean annual temperature at the site assures that the soluble, insoluble, and isotopic components of the core are well preserved.

In 2001 and …

Glaciology Of Blue Ice Areas In Antarctica, Gordon Hamilton

University of Maine Office of Research Administration: Grant Reports

A 'horizontal ice core' was collected at the Mount Moulton blue ice field in West Antarctica and preliminary analyses of the sample material suggests that a ~500 kyr climate record is preserved in the ice at this site. This award will contribute to the understanding of the Mt Moulton record by assessing the potential for ice-flow induced deformation of the stratigraphic profile. In addition, this award builds on the recognition of blue ice areas as archives of long climate records by conducting reconnaissance studies for a potential horizontal ice core location at the Allan Hills in East Antarctica. The objectives …

A Science Management Office For The U. S. Component Of The International Trans Antarctic Expedition (Us Itase Smo)Ûa Collaborative Pgrm Of Research From S. Pole To N. Victoria Land, Paul A. Mayewski, Gordon S. Hamilton

University of Maine Office of Research Administration: Grant Reports

This award supports a science management office for a pilot ice-core drilling and analysis program to test the feasibility of obtaining well-dated, high-resolution isotope and chemistry records from East Antarctica. Shallow ice cores will be obtained from two locations: 1) ~100 km from South Pole towards the Pole of Inaccessibility, as an extension of the Byrd Station-to-South Pole ITASE traverse [International Trans Antarctic Scientific Expedition]; 2) at Taylor Dome, near the original deep coring site, and (3) possibly at AGO 3 and AGO 4 as part of a logistics traverse to these sites. All of the cores collected will be …

Glacial History Of The Amundsen Sea Shelf, Thomas B. Kellogg, Daniel Belknap, Davida Kellogg, Terence Hughes

University of Maine Office of Research Administration: Grant Reports

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a marine geological investigation of the Amundsen Sea region toward a better understanding of the deglaciation history of the West Antarctic Ice Sheet (WAIS). The WAIS may be inherently unstable because it is the last marine-based ice sheet in the world. Unlike other embayments in West Antarctica, major ice streams draining into the Amundsen Sea from the interior of the WAIS lack buttressing ice shelves. Mass balance data for the distal portions of these ice streams (Pine Island and Thwaites glaciers) appear to …

Collaborative Research: Southern Andes Paleoclimate; A Testof Abrupt Ocean-Atmosphere Reorganizations In Glacial Cycle, George Denton

University of Maine Office of Research Administration: Grant Reports

In the late 1980s, Broecker and Denton prepared papers on the concept that glacial-to-interglacial transitions involved global reorganizations of the ocean-atmosphere system (Broecker, W. S. and Denton, G. H., 1989. The role of ocean-atmosphere reorganizations in glacial cycles. Geochimica et Cosmochimica Acta, 53, 2465-2501; Broecker, W. S. and Denton, G. H., 1990, What drives glacial cycles? Sci. American, 262, 49-56). These reorganizations were thought to constitute jumps of Earth's climate systems between stable modes of operation, and they featured changes in the greenhouse-gas content or reflectivity of the atmosphere. In that concept, switches in thermohaline circulation, resulting from changes in …

A New Ice Core From The Devon Ice Cap Canadian Arctic: Continued Development Of High-Resolution Proxy Records To Evaluate The Regionalization Of Climate In The Circum-Arctic, George A. Zielinski, Cameron Wake

University of Maine Office of Research Administration: Grant Reports

The primary goal of this project was to collect an ice core from the Summit of the Devon Ice Cap, Devon Island, Canadian Arctic. A 302-m core was collected during the spring of 1998 with additional field work in 1999. Individuals supported by this grant participated in the field work, although the GSC did the actual drilling. Glacier flow models as well as physical characteristics of the ice and d18O records suggest that basal ice recovered is about 86,000 years old. The first 200 meters were collected under dry drilling conditions, whereas the final 52 meters were collected with a …

Examination Of The 500,000-Year Climate Record In Ice At Mt. Moulton, West Antarctica, Gregory A. Zielinski, Paul Andrew Mayewski

University of Maine Office of Research Administration: Grant Reports

This project was a pilot project to determine if the ice on Mt. Moulton provides a reliable record of past climatic conditions. The area of study is a several hundred-meter section of blue ice (Trench A) that spans the time period from approximately the early Holocene to over 492k years ago. Dating control is obtained through radiometrically-dated tephra layers (i.e., air fall deposits) within the section (Figure 1) originating from the adjacent Mt. Berlin. Fieldwork during the 1999-2000 field season included the trenching of the complete section with electric chain saws mounted on a wheeled frame. Blocks were extracted and …

Acquisition Of Ion Chromatographs And Related Glaciochemistry Equipment, Paul Andrew Mayewski

University of Maine Office of Research Administration: Grant Reports

The goal of this project has been to upgrade the ice core processing and analytical equipment. This has been accomplished in three major areas: the design and construction of an ice core lathe, develpoment of a continuous melting system, and new ion chromatographs. The lathe is a unique ice core processing tool that operates similiar to a wood lathe. The lathe will reduce or eliminate the need for the cores to be hand scraped, the first cleaning step of core preparation.

Our continuous melting system is a modification of existing designs. Unlike other systems, we will collect discrete samples for …

Climate Of Nebraska, Richard E. Myers

Conservation and Survey Division

No abstract provided.

Irrigation Scheduling Of Corn Utilizing Infrared Thermometry, Kirk L. Clawson

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.