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Articles 1 - 21 of 21

Full-Text Articles in Geography

Techniques For Tree Species Classification With Hyperspectral Imagery At Neon Science Sites, Anthony T. Albanese May 2023

Techniques For Tree Species Classification With Hyperspectral Imagery At Neon Science Sites, Anthony T. Albanese

Theses and Dissertations

Studies three sets of techniques for hyperspectral tree species classification at NEON science sites, aiming to work towards producing a general classification model.


Correlation Of Road Network Structure And Urban Mobility Intensity: An Exploratory Study Using Geo-Tagged Tweets, Li Geng, Ke Zhang Dec 2022

Correlation Of Road Network Structure And Urban Mobility Intensity: An Exploratory Study Using Geo-Tagged Tweets, Li Geng, Ke Zhang

Publications and Research

Urban planners have been long interested in understanding how urban structure and activities are mutually influenced. Human mobility and economic activities naturally drive the formation of road network structure and the accessibility of the latter shapes the patterns of movement flow across urban space. In this paper, we perform an exploratory study on the relationship between the street network structure and the intensity of human movement in urban areas. We focus on two cities and we utilize a dataset of geo-tagged tweets that can form a proxy to urban mobility and the corresponding street networks as obtained from OpenStreetMap. We …


Studying Factors Of Environmental Injustice And Ways To Achieve Equity, Arham Hussain, Reginald Metellus Dec 2022

Studying Factors Of Environmental Injustice And Ways To Achieve Equity, Arham Hussain, Reginald Metellus

Publications and Research

In today's day of age, the biggest concern for current and future generations: the environment. The urban heat island (UHi) with its significant energy, health, and societal impacts is among the major environmental issues in urban regions, especially in historically underserved and socially vulnerable communities (HUSVCs). In the 1930s, the former federal agency, Homeowners' Loan Corporation (H0Lq, created ''Residential Security" maps of major cities, known today as "redlined" areas. These neighborhoods were often designated as "hazardous" due to the high percentages of people of color living there, leading to systematic disinvestment based on race. While the program ended in 1968, …


Systematic Review Of A Ramsar Wetland And Unesco Biosphere Reserve In A Climate Change Hotspot (Ichkeul Lake, Tunisia), Sabrine Sahbani, Béchir Béjaoui, Sihem Benabdalla, Rachid Toujani, Afef Fathalli, Noureddine Zaaboub, Jalel Aouissi, Zeineb Kassouk, Nabil Hamdi, Nabiha Ben Mbarek, Hechmi Missaoui, Leila Basti, Reginald Blake, Hamidreza Norouzi Dec 2022

Systematic Review Of A Ramsar Wetland And Unesco Biosphere Reserve In A Climate Change Hotspot (Ichkeul Lake, Tunisia), Sabrine Sahbani, Béchir Béjaoui, Sihem Benabdalla, Rachid Toujani, Afef Fathalli, Noureddine Zaaboub, Jalel Aouissi, Zeineb Kassouk, Nabil Hamdi, Nabiha Ben Mbarek, Hechmi Missaoui, Leila Basti, Reginald Blake, Hamidreza Norouzi

Publications and Research

Tunisia's Ichkeul Lake is among the most productive ecosystems in the Mediterranean, with a great regional value thanks to its diversity of habitats. It is an important overwintering area for waterfowl species. It is a RAMSAR wetland, a National Park, a UNESCO World Heritage, and a Biosphere Reserve. This review paper provides a broad overview of the climatic, hydraulic, biogeochemical features, bio-resources, and bio-productivity of the Lake. The interconnectivity between the different environmental components of the lake is presented, highlighting the main characteristics of this vital ecosystem. Its ecosystem consists of a permanent lake bordered by temporary marshes. It is …


Remote Sensing & Land Surface Temperature From Satellite Observations, Isatu Jollah May 2022

Remote Sensing & Land Surface Temperature From Satellite Observations, Isatu Jollah

Publications and Research

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument is designed and developed in 1995. • It is a critical instrument aboard Terra and Aqua satellites. Terra's orbit around the Earth is timed so that it crosses the equator from north to south in the morning, while Aqua crosses the equator from south to north in the afternoon. • Every 1 to 2 days, Terra MODIS and Aqua MODIS scan the entire Earth's surface, collecting data in groups of wavelengths. • In this research, a whole month of MODIS Land Surface Temperature data from both Aqua and Terra were explored and investigated.


Lake Satellite Temperature Data Validation, Mamadou Balde, Pascal Kouogang May 2022

Lake Satellite Temperature Data Validation, Mamadou Balde, Pascal Kouogang

Publications and Research

In environmental remote sensing, satellite data isn't absolutely conclusive, for that reason, there is a natural need to verify the data acquired from the satellite. The most suitable tool to achieve such verification is on ground sensors that have the advantage of proximity. Addressing any possible discrepancies between the satellite data and the ground sensor data is sure to yield ways to come up with improvements of satellite band calibration and sensing capabilities. This research focused on correlating temperature data from the MODIS satellite with the data obtained from the In Situ sensor located in Lake Sunapee. Doing the latter …


Spatial Downscaling Of Goes-R Land Surface Temperature Over Urban Regions: A Case Study For New York City, Abdou Bah, Hamidreza Norouzi, Satya Prakash, Reginald Blake, Reza Khanbilvardi, Cynthia Rosenzweig Feb 2022

Spatial Downscaling Of Goes-R Land Surface Temperature Over Urban Regions: A Case Study For New York City, Abdou Bah, Hamidreza Norouzi, Satya Prakash, Reginald Blake, Reza Khanbilvardi, Cynthia Rosenzweig

Publications and Research

The surface urban heat island (SUHI) effect is among the major environmental issues encountered in urban regions. To better predict the dynamics of the SUHI and its impacts on extreme heat events, an accurate characterization of the surface energy balance in urban regions is needed. However, the ability to improve understanding of the surface energy balance is limited by the heterogeneity of surfaces in urban areas. This study aims to enhance the understanding of the urban surface energy budget through an innovation in the use of land surface temperature (LST) observations from remote sensing satellites. A LST database with 5–min …


A Fused Radar–Optical Approach For Mapping Wetlands And Deepwaters Of The Mid–Atlantic And Gulf Coast Regions Of The United States, Brian T. Lamb, Maria A. Tzortziou, Kyle C. Mcdonald Jun 2021

A Fused Radar–Optical Approach For Mapping Wetlands And Deepwaters Of The Mid–Atlantic And Gulf Coast Regions Of The United States, Brian T. Lamb, Maria A. Tzortziou, Kyle C. Mcdonald

Publications and Research

Tidal wetlands are critically important ecosystems that provide ecosystem services including carbon sequestration, storm surge mitigation, water filtration, and wildlife habitat provision while supporting high levels of biodiversity. Despite their importance, monitoring these systems over large scales remains challenging due to difficulties in obtaining extensive up-to-date ground surveys and the need for high spatial and temporal resolution satellite imagery for effective space-borne monitoring. In this study, we developed methodologies to advance the monitoring of tidal marshes and adjacent deepwaters in the Mid-Atlantic and Gulf Coast United States. We combined Sentinel-1 SAR and Landsat 8 optical imagery to classify marshes and …


Digital Earth: The Impact Of Geographic Technology Through The Ages, Mishka Vance Huq May 2021

Digital Earth: The Impact Of Geographic Technology Through The Ages, Mishka Vance Huq

Theses and Dissertations

Geographic technology encompasses a wide range of geographic knowledge, concepts, processes, and artifacts. Because of its interdisciplinarity and integration with other technologies, the paper examines the diffuse impacts of geographic technology within the evolving relationship between technological and societal developments over time.


Investigating Water Usage Patterns Tied To California State Water Project, Xiaoqing Wu May 2021

Investigating Water Usage Patterns Tied To California State Water Project, Xiaoqing Wu

Publications and Research

California (USA) is the largest agricultural producer and one of the populous states in the United State. As the population and agriculture grows, water consumption patterns become crucial to keep track of especially surface water. In this research project, we studied possible changes in water consumption patterns in different counties and water rights holders who obtain surface water supply from the State Water Project (SWP) in California. We conducted a time series analysis on the California Monthly Diverted Surface Water dataset through two different time series forecasting models. Our analysis indicates that the total diverted surface water presents a periodic …


Diurnal Cycle Of Passive Microwave Brightness Temperatures Over Land At A Global Scale, Zahra Sharifnezhad, Hamid Norouzi, Satya Prakash, Reginald Blake, Reze Khanbilvard Feb 2021

Diurnal Cycle Of Passive Microwave Brightness Temperatures Over Land At A Global Scale, Zahra Sharifnezhad, Hamid Norouzi, Satya Prakash, Reginald Blake, Reze Khanbilvard

Publications and Research

Satellite-borne passive microwave radiometers provide brightness temperature (TB) measurements in a large spectral range which includes a number of frequency channels and generally two polarizations: horizontal and vertical. These TBs are widely used to retrieve several atmospheric and surface variables and parameters such as precipitation, soil moisture, water vapor, air temperature profile, and land surface emissivity. Since TBs are measured at different microwave frequencies with various instruments and at various incidence angles, spatial resolutions, and radiometric characteristics, a mere direct integration of them from different microwave sensors would not necessarily provide consistency. However, when appropriately harmonized, they can provide a …


Fine-Grained, Spatiotemporal Datasets Measuring 200 Years Of Land Development In The United States, Johannes H. Uhl, Stefan Leyk, Caitlin M. Mcshane, Anna E. Braswell, Dylan S. Connor, Deborah Balk Jan 2021

Fine-Grained, Spatiotemporal Datasets Measuring 200 Years Of Land Development In The United States, Johannes H. Uhl, Stefan Leyk, Caitlin M. Mcshane, Anna E. Braswell, Dylan S. Connor, Deborah Balk

Publications and Research

The collection, processing, and analysis of remote sensing data since the early 1970s has rapidly improved our understanding of change on the Earth’s surface. While satellite-based Earth observation has proven to be of vast scientific value, these data are typically confined to recent decades of observation and often lack important thematic detail. Here, we advance in this arena by constructing new spatially explicit settlement data for the United States that extend back to the early 19th century and are consistently enumerated at fine spatial and temporal granularity (i.e. 250m spatial and 5-year temporal resolution). We create these time series using …


An Application Of The Sleuth Model: Future Urbanization Of Davidson County, Tennessee, Caitlyn J. Linehan Jan 2021

An Application Of The Sleuth Model: Future Urbanization Of Davidson County, Tennessee, Caitlyn J. Linehan

Theses

As the urban population is expected to grow in the coming decades, there is pressure on urban areas to expand to accommodate this growth. Often times, these expansions are not sustainable, they consume valuable lands and cause significant environmental, social, and economic burdens, a theory which is known as urban sprawl. Therefore it is often imperative to model areas more likely to urbanize in order for cities to plan for their expansion in the most sustainable way possible. Nashville, Tennessee located within Davidson County is an area that has been experiencing a significant period of urban growth. The objective of …


The Quest For Greener Pastures: Evaluating The Livelihoods Impacts Of Providing Vegetation Condition Maps To Pastoralists In Eastern Africa, Elia Machado, Helene Purcell, Andrew M. Simons, Stephanie Swinehart Sep 2020

The Quest For Greener Pastures: Evaluating The Livelihoods Impacts Of Providing Vegetation Condition Maps To Pastoralists In Eastern Africa, Elia Machado, Helene Purcell, Andrew M. Simons, Stephanie Swinehart

Publications and Research

The survival of millions of pastoral households in Eastern Africa has become increasingly at risk. Due to mounting socioeconomic and climatic stressors, pastoral households are faced with making migration decisions under increasing uncertainty about resource availability and limited coping strategies. We assess the potential of providing vegetation condition maps to support the migration decision of pastoralists in Ethiopia and Tanzania and the effect of map usage on their herd condition and size. The maps were generated from remotely sensed data using the Normalized Difference Vegetation Index (NDVI) as a proxy for vegetation condition and overlain with pastoralists’ preferred grazing areas. …


Snow-Albedo Feedback In Northern Alaska: How Vegetation Influences Snowmelt, Lucas C. Reckhaus Aug 2020

Snow-Albedo Feedback In Northern Alaska: How Vegetation Influences Snowmelt, Lucas C. Reckhaus

Theses and Dissertations

This paper investigates how the snow-albedo feedback mechanism of the arctic is changing in response to rising climate temperatures. Specifically, the interplay of vegetation and snowmelt, and how these two variables can be correlated. This has the potential to refine climate modelling of the spring transition season. Research was conducted at the ecoregion scale in northern Alaska from 2000 to 2020. Each ecoregion is defined by distinct topographic and ecological conditions, allowing for meaningful contrast between the patterns of spring albedo transition across surface conditions and vegetation types. The five most northerly ecoregions of Alaska are chosen as they encompass …


Utilizing Collocated Crop Growth Model Simulations To Train Agronomic Satellite Retrieval Algorithms, Nathaniel Levitan, Barry Gross Jan 2018

Utilizing Collocated Crop Growth Model Simulations To Train Agronomic Satellite Retrieval Algorithms, Nathaniel Levitan, Barry Gross

Publications and Research

Due to its worldwide coverage and high revisit time, satellite-based remote sensing provides the ability to monitor in-season crop state variables and yields globally. In this study, we presented a novel approach to training agronomic satellite retrieval algorithms by utilizing collocated crop growth model simulations and solar-reflective satellite measurements. Specifically, we showed that bidirectional long short-term memory networks (BLSTMs) can be trained to predict the in-season state variables and yields of Agricultural Production Systems sIMulator (APSIM) maize crop growth model simulations from collocated Moderate Resolution Imaging Spectroradiometer (MODIS) 500-m satellite measurements over the United States Corn Belt at a regional …


Land Change History Of Oil Palm Plantations In Northern Bengkulu Province, Sumatra Island, Reconstructed From Landsat Satellite Archives, Atsushi Tomita Feb 2017

Land Change History Of Oil Palm Plantations In Northern Bengkulu Province, Sumatra Island, Reconstructed From Landsat Satellite Archives, Atsushi Tomita

Dissertations, Theses, and Capstone Projects

The aim of this study is to reconstruct the history of land conversion to oil palm plantation in tropical Asia using multi-temporal satellite data. A new method was constructed with a newly developed computer model, Land Change Detection and Land Definition Model (LC/LD Model) to map out spatio-temporal distribution of land changes. A comprehensive, cloud-free Landsat dataset was created from all the available Landsat data from 1988 to 2015. The pixel-based dataset was converted into a polygon-based dataset by applying the multi-temporal image segmentation method. The representation of the spectral information was also reduced to a single index of IB45, …


Aerosol And Urban Heat Island Effects On Warm Cloud-Top Shortwave Infrared Reflectance And Visible Albedo, Heather Glickman-Eliezer Sep 2015

Aerosol And Urban Heat Island Effects On Warm Cloud-Top Shortwave Infrared Reflectance And Visible Albedo, Heather Glickman-Eliezer

Dissertations, Theses, and Capstone Projects

This study uses ten years of Geostationary Operational Environmental Satellite (GOES) data (1999-2009) to assess urban effects of anthropogenic aerosols and Urban Heat Island (UHI) on cloud-top radiative properties of optically thick clouds. GOES images at noon local time of channels 1, 2, and 4 are used to calculate visible albedo, and shortwave infrared reflectance at 3.9-µm. Cloud-top particle radius is inversely related with SWIRR. Albedo and cloud fraction are measured for cold and warm clouds, and SWIRR is used as a particle-radius proxy for warm clouds only. AERONET fine-mode particle retrievals (fAOD) from the CCNY station are used for …


Effects Of Temperature Stress On Coral Fluorescence And Reflectance, Andrea Gomez Jan 2015

Effects Of Temperature Stress On Coral Fluorescence And Reflectance, Andrea Gomez

Dissertations and Theses

Around the world, climate change, land-based pollution and fishing impacts are recognized as principal threats to coral reef ecosystems. Sea surface temperatures, in particular, are expected to change dramatically over the next decades and result in high coral mortality in some regions. Through controlled experiments, I examined changes in coral fluorescence and reflectance in response to water temperature alterations to assess the potential of employing these signatures as a diagnostic tool to measure coral health. At the NOAA Coral Culture and Collaborative Research Facility, I conducted controlled laboratory-based heat stress experiments on three Caribbean species of coral: Acropora cervicornis, Orbicella …


Mapping Forest Canopy Structure With On-Demand Fusion Of Remotely Sensed Data, Gordon M. Green Oct 2014

Mapping Forest Canopy Structure With On-Demand Fusion Of Remotely Sensed Data, Gordon M. Green

Dissertations, Theses, and Capstone Projects

Current methods of mapping forest canopy structure often result in data products that are limited in resolution, coverage, or ease of access. On-demand processing introduces several new ways in which existing data products can be combined and re-purposed, mitigating some of these limitations. In this research, we investigate several methods of extending the spatial and temporal resolution, coverage, and accessibility of existing forest canopy datasets by processing them on demand. These methods include downscaling coarse-resolution canopy height data dynamically to estimate height at 30 m and 1 m resolution for any location within the contiguous United States. A related method …


Allometric Scaling And Resource Limitations Model Of Tree Heights: Part 2. Site Based Testing Of The Model, Sungho Choi, Xiliang Ni, Yuli Shi, Sangram Ganguly, Gong Zhang, Hieu V. Duong, Michael A. Lefsky, Marc Simard, Sassan S. Saatchi, Shihyan Lee, Wenge Ni-Meister, Shilong Piao, Chunxiang Cao, Ramakrishna R. Nemani, Ranga B. Myneni Jan 2013

Allometric Scaling And Resource Limitations Model Of Tree Heights: Part 2. Site Based Testing Of The Model, Sungho Choi, Xiliang Ni, Yuli Shi, Sangram Ganguly, Gong Zhang, Hieu V. Duong, Michael A. Lefsky, Marc Simard, Sassan S. Saatchi, Shihyan Lee, Wenge Ni-Meister, Shilong Piao, Chunxiang Cao, Ramakrishna R. Nemani, Ranga B. Myneni

Publications and Research

The ultimate goal of this multi-article series is to develop a methodology to generate continuous fields of tree height and biomass. The first paper demonstrated the need for Allometric Scaling and Resource Limitation (ASRL) model optimization and its ability to generate spatially continuous fields of tree heights over the continental USA at coarse (1 km) spatial resolution. The objective of this second paper is to provide an assessment of that approach at site scale, specifically at 12 FLUXNET sites where more accurate data are available. Estimates of tree heights from the Geoscience Laser Altimeter System (GLAS) waveform data are used …