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Articles 61 - 90 of 383

Full-Text Articles in Geography

Protecting Brazilian Amazon Indigenous Territories Reduces Atmospheric Particulates And Avoids Associated Health Impacts And Costs, Paula R. Priest, Florencia Sangermano, Allison Bailey, Victoria Bugni, María Del Carmen Villalobos-Segura, Nataly Pimiento-Quiroga, Peter Daszak, Carlos Zambrana-Torrelio Dec 2023

Protecting Brazilian Amazon Indigenous Territories Reduces Atmospheric Particulates And Avoids Associated Health Impacts And Costs, Paula R. Priest, Florencia Sangermano, Allison Bailey, Victoria Bugni, María Del Carmen Villalobos-Segura, Nataly Pimiento-Quiroga, Peter Daszak, Carlos Zambrana-Torrelio

Geography

Indigenous territories are considered important for conservation, but little is known about their role in maintaining human health. Here we quantified the potential human health and economic benefits of protecting these territories in the Brazilian Amazon, by using cardiovascular and respiratory diseases cases, pollutant and forest cover data. Between 2010 and 2019, 1.68 tons of Particulate Matter of small size (PM2.5) were released every year, with negative effects for human health. A lower number of infections was also found in municipalities with more forested areas, and with a low level of fragmentation, which probably is related to the …

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Examining Current Bias And Future Projection Consistency Of Globally Downscaled Climate Projections Commonly Used In Climate Impact Studies, Lucas Berio Fortini, Lauren R. Kaiser, Abby Frazier, Thomas W. Giambelluca Dec 2023

Examining Current Bias And Future Projection Consistency Of Globally Downscaled Climate Projections Commonly Used In Climate Impact Studies, Lucas Berio Fortini, Lauren R. Kaiser, Abby Frazier, Thomas W. Giambelluca

Geography

The associated uncertainties of future climate projections are one of the biggest obstacles to overcome in studies exploring the potential regional impacts of future climate shifts. In remote and climatically complex regions, the limited number of available downscaled projections may not provide an accurate representation of the underlying uncertainty in future climate or the possible range of potential scenarios. Consequently, global downscaled projections are now some of the most widely used climate datasets in the world. However, they are rarely examined for representativeness of local climate or the plausibility of their projected changes. Here we explore the utility of two …

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Stories Of Challenge In South Africa: Changes In The Enabling Environment For Nutrition Among Young Children (1994–2021), Scott Drimie, Mara Van Den Bold, Lisanne Du Plessis, Laura Casu Dec 2023

Stories Of Challenge In South Africa: Changes In The Enabling Environment For Nutrition Among Young Children (1994–2021), Scott Drimie, Mara Van Den Bold, Lisanne Du Plessis, Laura Casu

Student Publications [Scholarly]

Despite important nutrition-related policy and programmatic improvements in South Africa, rates of stunting among young children remain unacceptably high, while rates of overweight and obesity in this same population group are simultaneously on the rise. This study sought to examine the changes in the enabling environment for nutrition aimed at young children in South Africa by drawing on a literature review, policy mapping, and stakeholder interviews, for the time period from the end of apartheid in 1994 to 2021. The study focuses on changes and drivers of change at national level but also in three provinces: Western Cape, North West, …

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In Africa, "Climate-Smart" Conservation Must Be Coupled With Poverty Alleviation, Saleem H. Ali, Penda Diallo, Apoli Bertrand Kameni, Philippe Le Billon, Kopo Oromeng, Kyle Frankel Davis, Edward Carr Oct 2023

In Africa, "Climate-Smart" Conservation Must Be Coupled With Poverty Alleviation, Saleem H. Ali, Penda Diallo, Apoli Bertrand Kameni, Philippe Le Billon, Kopo Oromeng, Kyle Frankel Davis, Edward Carr

Geography

In August, the Seventh Assembly of the Global Environment Facility (GEF) concluded in Vancouver, Canada, with a pledge. A total of 185 countries agreed to protect 30% of land and coastal areas by 2030 (known as the “30 by 30 pledge”). But while this surge of conservation funding is heartening, there are serious concerns. Projects and programs that appear to produce both environmental and developmental goals could actually obscure the continuing marginalization of poor and vulnerable populations. Here, we suggest that such coupling of conservation and extraction needs to pay greater attention to poverty alleviation. Otherwise, it risks further marginalizing …

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Structural Tensions Limiting Success Of Infrastructure Upgrading: A Multi-Regime Perspective, George Kiambuthi Wainaina, Bernhard Truffer, James T. Murphy Sep 2023

Structural Tensions Limiting Success Of Infrastructure Upgrading: A Multi-Regime Perspective, George Kiambuthi Wainaina, Bernhard Truffer, James T. Murphy

Geography

Unfettered growth of slums is a daunting transition challenge and many upgrading programs fail to sustainably improve the livelihoods of slum residents. This paper elaborates a transitions perspective on structural tensions that may lead to success or failure of slum upgrading programs. We conceptualize slums as urban subsystems, governed by sociotechnical (infrastructure) and socioeconomic livelihood regimes (related to production and social reproduction). The framework permits examination of the tensions due to mis/alignments of rules associated with newly introduced infrastructures, and those that regulate existing production and social reproduction practices of slum residents. This approach extends transition studies by accounting for …

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Improved Fine-Scale Tropical Forest Cover Mapping For Southeast Asia Using Planet-Nicfi And Sentinel-1 Imagery, Feng Yang, Xin Jiang, Alan D. Ziegler, Lyndon Estes, Jin Wu, Anping Chen, Philippe Ciais Aug 2023

Improved Fine-Scale Tropical Forest Cover Mapping For Southeast Asia Using Planet-Nicfi And Sentinel-1 Imagery, Feng Yang, Xin Jiang, Alan D. Ziegler, Lyndon Estes, Jin Wu, Anping Chen, Philippe Ciais

Geography

The accuracy of existing forest cover products typically suffers from “rounding” errors arising from classifications that estimate the fractional cover of forest in each pixel, which often exclude the presence of large, isolated trees and small or narrow forest clearings, and is primarily attributable to the moderate resolution of the imagery used to make maps. However, the degree to which such high-resolution imagery can mitigate this problem, and thereby improve large-area forest cover maps, is largely unexplored. Here, we developed an approach to map tropical forest cover at a fine scale using Planet and Sentinel-1 synthetic aperture radar (SAR) imagery …

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The Flow Matrix Offers A Straightforward Alternative To The Problematic Markov Matrix, Jessica Stzempko, Robert Gilmore Pontius Jul 2023

The Flow Matrix Offers A Straightforward Alternative To The Problematic Markov Matrix, Jessica Stzempko, Robert Gilmore Pontius

Geography

The Flow matrix is a novel method to describe and extrapolate transitions among categories. The Flow matrix extrapolates a constant transition size per unit of time on a time continuum with a maximum of one incident per observation during the extrapolation. The Flow matrix extrapolates linearly until the persistence of a category shrinks to zero. The Flow matrix has concepts and mathematics that are more straightforward than the Markov matrix. However, many scientists apply the Markov matrix by default because popular software packages offer no alternative to the Markov matrix, despite the conceptual and mathematical challenges that the Markov matrix …

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Cropland Mapping In Tropical Smallholder Systems With Seasonally Stratified Sentinel-1 And Sentinel-2 Spectral And Textural Features, Manushi B. Trivedi, Michael Marshall, Lyndon Estes, C.A.J.M. De Bie, Ling Chang, Andrew Nelson Jun 2023

Cropland Mapping In Tropical Smallholder Systems With Seasonally Stratified Sentinel-1 And Sentinel-2 Spectral And Textural Features, Manushi B. Trivedi, Michael Marshall, Lyndon Estes, C.A.J.M. De Bie, Ling Chang, Andrew Nelson

Geography

Mapping arable field areas is crucial for assessing agricultural productivity but poses challenges in sub-Saharan agroecosystems because of diverse crop calendars, small and irregularly shaped fields, persistent cloud cover, and lack of high-quality model training data. This study proposes several methodological improvements to overcome these challenges. Specifically, it utilizes long-term MODIS data to stratify finer Sentinel-2 reflectance and Sentinel-1 backscatter image features on a per-pixel basis. It also incorporates texture features and employs a machine learning approach with over 300,000 samples. The eastern region of Ghana was stratified into seven seasonal strata exhibiting distinct vegetation seasonality, capturing diversity in crop …

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Disturbance Regimes And Management Strategies Of Mountain Ash Forest Ecosystems In Victoria, Australia; A Literature Review, Zoe Plumb May 2023

Disturbance Regimes And Management Strategies Of Mountain Ash Forest Ecosystems In Victoria, Australia; A Literature Review, Zoe Plumb

Sustainability and Social Justice

This paper discusses the ecology of mountain ash forests, the disturbances regimes that currently exist in these ecosystems, and finally addresses the current management practices and future management practices. Mountain ash forests are subjected to a wide range of research in the Central Highlands of Victoria, an area approximately 14,000 hectares in range. These forests are dominated by montane ash trees (Eucalyptus regnans F. Muell), which are critically endangered and at risk of collapse, attributed to the decline in large hollow-bearing trees throughout the region. Management of these forests are controlled by the Department of Environment, Land, Water, and …

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Pandemic Produce: Impacts Of Covid-19 On Florida's Fruit And Vegetable Industries, Christa D. Court, David Outerbridge, Lauri Baker, Laura Birou, Catherine Campbell, Gigi Digiacomo, Sebastian Galindo, John Lai, Alexandre Magnier, Michelle Miller, Gustavo De L.T. Oliveira, Eyrika Orlando, Hikaru Hanawa Peterson, Xiaohui Qiao, Fritz Roka, Andrew Ropicki, Bijeta Bijen Saha, Andrew W. Stevens, Li Zhang May 2023

Pandemic Produce: Impacts Of Covid-19 On Florida's Fruit And Vegetable Industries, Christa D. Court, David Outerbridge, Lauri Baker, Laura Birou, Catherine Campbell, Gigi Digiacomo, Sebastian Galindo, John Lai, Alexandre Magnier, Michelle Miller, Gustavo De L.T. Oliveira, Eyrika Orlando, Hikaru Hanawa Peterson, Xiaohui Qiao, Fritz Roka, Andrew Ropicki, Bijeta Bijen Saha, Andrew W. Stevens, Li Zhang

Geography

Florida has one of the most diverse agricultural economies in the United States, producing several dozen types of fruits and vegetables that are consumed within the state, across the country, and around the world. The COVID-19 pandemic and resulting policy responses occurred during the peak of spring harvest season for many crops in Florida, abruptly removing market demand from the food service industry and shifting consumer purchasing habits, which enabled insights into several aspects of the fruit and vegetable supply chain. This article examines how the COVID-19 pandemic impacted fruit and vegetable industries in Florida, how these industries responded to …

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Is Closing The Agricultural Yield Gap A "Risky" Endeavor?, Nicolas Gatti, Michael Cecil, Kathy Baylis, Lyndon Estes, Jordan Blekking, Thomas Heckelei, Noemi Vergopolan, Tom Evans May 2023

Is Closing The Agricultural Yield Gap A "Risky" Endeavor?, Nicolas Gatti, Michael Cecil, Kathy Baylis, Lyndon Estes, Jordan Blekking, Thomas Heckelei, Noemi Vergopolan, Tom Evans

Geography

CONTEXT: Sub-Saharan Africa (SSA) has the climatic and biophysical potential to grow the crops it needs to meet rapidly growing food demand; however, agricultural productivity remains low. While potential maize yields in Zambia are 9 t per hectare (t/ha), the average farmer produces only 1–2. OBJECTIVE: We evaluate the contribution of responses to weather risk to that gap by decomposing the yield gap in maize in Zambia. While we know that improved seed and fertilizer can expand yield and profit, they may also increase the variance of yield under different weather outcomes, reducing their adoption. METHODS: We use a novel …

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Limited Evidence Of Cumulative Effects From Recurrent Droughts In Vegetation Responses To Australia's Millennium Drought, Tong Jiao, Christopher A. Williams, Martin De Kauwe, Belinda E. Medlyn May 2023

Limited Evidence Of Cumulative Effects From Recurrent Droughts In Vegetation Responses To Australia's Millennium Drought, Tong Jiao, Christopher A. Williams, Martin De Kauwe, Belinda E. Medlyn

Geography

Drought-induced vegetation declines have been reported across the globe and may have widespread implications for ecosystem composition, structure, and functions. Thus, it is critical to maximizing our understanding of how vegetation has responded to recent drought extremes. To date, most drought assessments emphasized the importance of drought intensity for vegetation responses. However, drought timing, duration, and repeat exposure all may be important aspects of ecosystem response with the potential for non-linear effects. Cumulative effects are one such phenomenon, representing the additional decline due to repeated exposure to drought, and indicating gradual loss of ecosystem resistance. This study quantifies the frequency …

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Changes In Nigeria’S Enabling Environment For Nutrition From 2008 To 2019 And Challenges For Reducing Malnutrition, Olutayo Adeyemi, Mara Van Den Bold, Nicholas Nisbett, Namukolo Covic Apr 2023

Changes In Nigeria’S Enabling Environment For Nutrition From 2008 To 2019 And Challenges For Reducing Malnutrition, Olutayo Adeyemi, Mara Van Den Bold, Nicholas Nisbett, Namukolo Covic

Student Publications [Scholarly]

Key 2025 global nutrition targets are unlikely to be met at current rates of progress. Although actions necessary to reduce undernutrition are already mostly known, knowledge gaps remain about how to implement these actions in contextually appropriate ways, and at scales commensurate with the magnitude of the problem. This study describes the nutrition enabling environment in Nigeria, a country that contributes significantly to the global undernutrition burden, and identifies potential entry points for improving the enabling environment that could facilitate implementation and scale-up of essential intervention coverage. Study data were obtained from two sources: content analysis of 48 policies/strategies from …

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Comparing The Trajectory Of Urban Impervious Surface In Two Cities: The Case Of Accra And Kumasi, Ghana, Thomas Mumuni Bilintoh, Andrews Korah, Antwi Opuni, Adeline Akansobe Apr 2023

Comparing The Trajectory Of Urban Impervious Surface In Two Cities: The Case Of Accra And Kumasi, Ghana, Thomas Mumuni Bilintoh, Andrews Korah, Antwi Opuni, Adeline Akansobe

Student Publications [Scholarly]

In this study, we present methods to assess newly developed urban impervious surface (UIS) datasets derived from satellite imagery of the cities of Kumasi and Accra, Ghana, at three different time points. Each city has three binary maps from 2000, 2011, and 2021, in which one shows the presence of UIS and zero shows its absence. We employed the binaryTimeSeries method to compare the gross gains and losses in the two cities. In addition, we show how three components of change—quantity, allocation, and alternation—compare across the two sites. The results show that both cities experienced a large proportion of gains …

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Reduced Fire Severity Offers Near-Term Buffer To Climate-Driven Declines In Conifer Resilience Across The Western United States, Kimberley T. Davis, Marcos D. Robles, Kerry B. Kemp, Philip E. Higuera, Teresa Chapman, Kerry L. Metlen, Jamie L. Peeler, Kyle C. Rodman, Travis Woolley, Robert N. Addington, Brian J. Buma, Alina C. Cansler, Michael J. Case, Brandon M. Collins, Jonathan D. Coop, Solomon Z. Dobrowski, Nathan S. Gill, Collin Haffey, Lucas B. Harris, Brian J. Harvey, Ryan D. Haugo, Matthew D. Hurteau, Dominik Kulakowski, Caitlin E. Littlefield, Lisa A. Mccauley, Nicholas Povak, Kristen L. Shive, Edward Smith, Jens T. Stevens, Camille S. Stevens-Rumann, Alan H. Taylor, Alan J. Tepley, Derek J.N. Young, Robert A. Andrus, Mike A. Battaglia, Julia K. Berkey, Sebastian U. Busby, Amanda R. Carlson, Marin E. Chambers, Erich Kyle Dodson, Daniel Donato, William M. Downing, Paula J. Fornwalt, Joshua S. Halofsky, Ashley Hoffman, Andrés Holz, Jose M. Iniguez, Meg A. Krawchuk, Mark R. Krieder, Andrew J. Larson, Garrett W. Meigs, John Paul Roccaforte, Monica T. Rother, Hugh Safford, Michael Schaedel, Jason S. Sibold, Megan P. Singleton, Alexandra K. Urza, Kyra D. Clark-Wolf, Monica G. Turner Mar 2023

Reduced Fire Severity Offers Near-Term Buffer To Climate-Driven Declines In Conifer Resilience Across The Western United States, Kimberley T. Davis, Marcos D. Robles, Kerry B. Kemp, Philip E. Higuera, Teresa Chapman, Kerry L. Metlen, Jamie L. Peeler, Kyle C. Rodman, Travis Woolley, Robert N. Addington, Brian J. Buma, Alina C. Cansler, Michael J. Case, Brandon M. Collins, Jonathan D. Coop, Solomon Z. Dobrowski, Nathan S. Gill, Collin Haffey, Lucas B. Harris, Brian J. Harvey, Ryan D. Haugo, Matthew D. Hurteau, Dominik Kulakowski, Caitlin E. Littlefield, Lisa A. Mccauley, Nicholas Povak, Kristen L. Shive, Edward Smith, Jens T. Stevens, Camille S. Stevens-Rumann, Alan H. Taylor, Alan J. Tepley, Derek J.N. Young, Robert A. Andrus, Mike A. Battaglia, Julia K. Berkey, Sebastian U. Busby, Amanda R. Carlson, Marin E. Chambers, Erich Kyle Dodson, Daniel Donato, William M. Downing, Paula J. Fornwalt, Joshua S. Halofsky, Ashley Hoffman, Andrés Holz, Jose M. Iniguez, Meg A. Krawchuk, Mark R. Krieder, Andrew J. Larson, Garrett W. Meigs, John Paul Roccaforte, Monica T. Rother, Hugh Safford, Michael Schaedel, Jason S. Sibold, Megan P. Singleton, Alexandra K. Urza, Kyra D. Clark-Wolf, Monica G. Turner

Geography

Increasing fire severity and warmer, drier postfire conditions are making forests in the western United States (West) vulnerable to ecological transformation. Yet, the relative importance of and interactions between these drivers of forest change remain unresolved, particularly over upcoming decades. Here, we assess how the interactive impacts of changing climate and wildfire activity influenced conifer regeneration after 334 wildfires, using a dataset of postfire conifer regeneration from 10,230 field plots. Our findings highlight declining regeneration capacity across the West over the past four decades for the eight dominant conifer species studied. Postfire regeneration is sensitive to high-severity fire, which limits …

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Unsettling Participation By Foregrounding More-Than-Human Relations In Digital Forests, Michelle Westerlaken, Jennifer Gabrys, Danilo Urzedo, Max Ritts Mar 2023

Unsettling Participation By Foregrounding More-Than-Human Relations In Digital Forests, Michelle Westerlaken, Jennifer Gabrys, Danilo Urzedo, Max Ritts

Geography

The question of who participates in making forest environments usually refers to human stakeholders. Yet forests are constituted through the participation of many other entities. At the same time, digital technologies are increasingly used in participatory projects to measure and monitor forest environments globally. However, such participatory initiatives are often limited to human involvement and overlook how more-than-human entities and relations shape digital and forest processes. To disrupt conventional anthropocentric understandings of participation, this text travels through three different processes of "unsettling"to show how more-than-human entities and relations disrupt, rework, and transform digital participation in and with forests. First, forest …

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A Super-Ensemble Approach To Map Land Cover Types With High Resolution Over Data-Sparse African Savanna Landscapes, Lei Song, Anna Bond Estes, Lyndon Despard Estes Feb 2023

A Super-Ensemble Approach To Map Land Cover Types With High Resolution Over Data-Sparse African Savanna Landscapes, Lei Song, Anna Bond Estes, Lyndon Despard Estes

Geography

Accurate and timely land cover products are critical inputs for landscape planning, and provide key information for biodiversity conservation and food security. However, poor mapping quality and low resolution are considerable issues in existing land cover maps over the African savanna, where land use is complex and changing rapidly, and necessary ground-truth data are sparse and hard to obtain. To overcome this problem, to make optimal use of existing maps, and to minimize manual training data collection, we developed a three-stage ensemble method to make land cover maps. In the first stage, we extracted the consensus of multiple existing land …

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Impacts Of Covid-19 On Us Agri-Food Supply Chain Businesses: Regional Survey Results, Hikaru Hanawa Peterson, Gigi Digiacomo, Christa D. Court, Michelle Miller, Gustavo Oliveira, Andrew W. Stevens, Li Zhang, Lauri M. Baker, Joseph Nowak, Eyrika Orlando, Bijeta Bijen Saha Feb 2023

Impacts Of Covid-19 On Us Agri-Food Supply Chain Businesses: Regional Survey Results, Hikaru Hanawa Peterson, Gigi Digiacomo, Christa D. Court, Michelle Miller, Gustavo Oliveira, Andrew W. Stevens, Li Zhang, Lauri M. Baker, Joseph Nowak, Eyrika Orlando, Bijeta Bijen Saha

Geography

Visible disruptions of appropriate food distribution for end consumers during the onset of the COVID-19 pandemic prompted calls for an urgent, renewed look at how the U.S. agri-food system is impacted by and responds to pandemics, natural disasters, and human-made crises. Previous studies suggest the COVID-19 pandemic yielded uneven impacts across agri-food supply chain segments and regions. For a rigorously comparable assessment of the impact of COVID-19 on agri-food businesses, a survey was administered from February to April 2021 to five segments of the agri-food supply chain in three study regions (California, Florida, and the two-state region of Minnesota-Wisconsin). Results …

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Estimates Of The Spatially Complete, Observational-Data-Driven Planetary Boundary Layer Height Over The Contiguous United States, Shiqi Tao, Zolal Ayazpour, Dan Li, Amy Jo Scarino, Ralph E. Kuehn, Kang Sun Jan 2023

Estimates Of The Spatially Complete, Observational-Data-Driven Planetary Boundary Layer Height Over The Contiguous United States, Shiqi Tao, Zolal Ayazpour, Dan Li, Amy Jo Scarino, Ralph E. Kuehn, Kang Sun

Student Publications [Scholarly]

This study aims to generate a spatially complete planetary boundary layer height (PBLH) product over the contiguous United States (CONUS). An eXtreme Gradient Boosting (XGB) regression model was developed using selected meteorological and geographical data fields as explanatory variables to fit the PBLH values derived from Aircraft Meteorological DAta Relay (AMDAR) reports hourly profiles at 13:00-14:00 LST (local solar time) during 2005-2019. A preprocessing step was implemented to exclude AMDAR data points that were unexplainable by the predictors, mostly under stable conditions. The PBLH prediction by this work as well as PBLHs from three reanalysis datasets (the fifth-generation European Centre …

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Itsdm: Isolation Forest-Based Presence-Only Species Distribution Modelling And Explanation In R, Lei Song, Lyndon Estes Jan 2023

Itsdm: Isolation Forest-Based Presence-Only Species Distribution Modelling And Explanation In R, Lei Song, Lyndon Estes

Geography

Multiple statistical algorithms have been used for species distribution modelling (SDM). Due to shortcomings in species occurrence datasets, presence-only methods (such as MaxEnt) have become increasingly widely used. However, sampling bias remains a challenging issue, particularly for density-based approaches. The Isolation Forest (iForest) algorithm is a presence-only method less sensitive to sampling patterns and over-fitting because it fits the model by describing the unsuitable instead of suitable conditions. Here, we present the itsdm package for species distribution modelling with iForest, which provides a workflow wrapper for the algorithms in iForest family and convenient tools for model diagnostic and post-modelling analysis. …

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Adaptation Rationales And Benefits: A Foundation For Understanding Adaptation Impact, Edward R. Carr, Johanna Nalau Jan 2023

Adaptation Rationales And Benefits: A Foundation For Understanding Adaptation Impact, Edward R. Carr, Johanna Nalau

Geography

Efforts to achieve coordinated, effective, and impactful adaptation outcomes are complicated by factors ranging from the local specificity of adaptation needs to the challenges of politics and prioritization that drive funding decisions. However, these and other challenges are perpetuated and exacerbated by poorly constructed, often implicit, and generally institution- or context-specific impact pathways connecting policy/institutional priorities through their materialization in specific actions to their intended outcomes. We call these impact pathways adaptation rationales, as they represent the logic of an adaptation action. The implicit nature of most current adaptation rationales makes it difficult to identify and test the accuracy and …

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A Comprehensive Satellite-Based Assessment Across The Pacific Arctic Distributed Biological Observatory Shows Widespread Late-Season Sea Surface Warming And Sea Ice Declines With Significant Influences On Primary Productivity, Karen E. Frey, Josefino C. Comiso, Larry V. Stock, Luisa N C Young, Lee W. Cooper, Jacqueline M. Grebmeier Jan 2023

A Comprehensive Satellite-Based Assessment Across The Pacific Arctic Distributed Biological Observatory Shows Widespread Late-Season Sea Surface Warming And Sea Ice Declines With Significant Influences On Primary Productivity, Karen E. Frey, Josefino C. Comiso, Larry V. Stock, Luisa N C Young, Lee W. Cooper, Jacqueline M. Grebmeier

Geography

Massive declines in sea ice cover and widespread warming seawaters across the Pacific Arctic region over the past several decades have resulted in profound shifts in marine ecosystems that have cascaded throughout all trophic levels. The Distributed Biological Observatory (DBO) provides sampling infrastructure for a latitudinal gradient of biological "hotspot" regions across the Pacific Arctic region, with eight sites spanning the northern Bering, Chukchi, and Beaufort Seas. The purpose of this study is two-fold: (a) to provide an assessment of satellite-based environmental variables for the eight DBO sites (including sea surface temperature (SST), sea ice concentration, annual sea ice persistence …

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Four Fundamental Questions To Evaluate Land Change Models With An Illustration Of A Cellular Automata–Markov Model, Cláudia M. Viana, Robert Gilmore Pontius, Jorge Rocha Jan 2023

Four Fundamental Questions To Evaluate Land Change Models With An Illustration Of A Cellular Automata–Markov Model, Cláudia M. Viana, Robert Gilmore Pontius, Jorge Rocha

Geography

Numerous models exist for users to simulate land change to communicate with an audience concerning future land change. This article raises four fundamental questions to help model users decide whether to use any model: (1) Can the user understand the model? (2) Can the audience understand the model? (3) Can the user control the model? (4) Does the model address the goals of the specific application? This article applies these questions to the popular cellular automata–Markov (CA–Markov) model as IDRISI’s CA–Markov module expresses. Sensitivity analysis examines 120 ways to set the module’s parameters. Verification compares the module’s behavior to the …

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Ten New Insights In Climate Science 2023/2024, Mercedes Bustamante, Joyashree Roy, Daniel Ospina, Ploy Achakulwisut, Anubha Aggarwal, Ana Bastos, Wendy Broadgate, Josep G. Canadell, Edward Carr, Deliang Chen, Helen A. Cleugh, Kristie L. Ebi Jan 2023

Ten New Insights In Climate Science 2023/2024, Mercedes Bustamante, Joyashree Roy, Daniel Ospina, Ploy Achakulwisut, Anubha Aggarwal, Ana Bastos, Wendy Broadgate, Josep G. Canadell, Edward Carr, Deliang Chen, Helen A. Cleugh, Kristie L. Ebi

Geography

Non-technical summary: We identify a set of essential recent advances in climate change research with high policy relevance, across natural and social sciences: (1) looming inevitability and implications of overshooting the 1.5°C warming limit, (2) urgent need for a rapid and managed fossil fuel phase-out, (3) challenges for scaling carbon dioxide removal, (4) uncertainties regarding the future contribution of natural carbon sinks, (5) intertwinedness of the crises of biodiversity loss and climate change, (6) compound events, (7) mountain glacier loss, (8) human immobility in the face of climate risks, (9) adaptation justice, and (10) just transitions in food systems. Technical …

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Situational Analysis And Urban Theory, Mark Davidson Jan 2023

Situational Analysis And Urban Theory, Mark Davidson

Geography

Urban geographers have been pursuing divergent theoretical projects. Some have pushed urban theory to become ageographical, the goal being to search out and explain of a globally omnipotent urbanization process. Others have moved in a different direction, seeking to detail how singular constellations of processes produce only particular urban places. This theoretical divergence has led some to question whether middle-range urban theories continue to have purchase today. This paper seeks to contribute to this attempt to rekindle an interest in middle-range urban theory by examining the relevance of Karl Popper’s situational analysis to how we understand contemporary urbanization. © The …

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A Century Of Drought In HawaiʻI: Geospatial Analysis And Synthesis Across Hydrological, Ecological, And Socioeconomic Scales, Abby G. Frazier, Christian P. Giardina, Thomas W. Giambelluca, Laura Brewington, Yi Leng Chen, Pao Shin Chu, Lucas Berio Fortini, Danielle Hall, David A. Helweg, Victoria W. Keener, Ryan J. Longman, Matthew P. Lucas, Alan Mair, Delwyn S. Oki, Julian J. Reyes, Stephanie G. Yelenik, Clay Trauernicht Oct 2022

A Century Of Drought In HawaiʻI: Geospatial Analysis And Synthesis Across Hydrological, Ecological, And Socioeconomic Scales, Abby G. Frazier, Christian P. Giardina, Thomas W. Giambelluca, Laura Brewington, Yi Leng Chen, Pao Shin Chu, Lucas Berio Fortini, Danielle Hall, David A. Helweg, Victoria W. Keener, Ryan J. Longman, Matthew P. Lucas, Alan Mair, Delwyn S. Oki, Julian J. Reyes, Stephanie G. Yelenik, Clay Trauernicht

Geography

Drought is a prominent feature of Hawaiʻi’s climate. However, it has been over 30 years since the last comprehensive meteorological drought analysis, and recent drying trends have emphasized the need to better understand drought dynamics and multi-sector effects in Hawaiʻi. Here, we provide a comprehensive synthesis of past drought effects in Hawaiʻi that we integrate with geospatial analysis of drought characteristics using a newly developed 100-year (1920–2019) gridded Standardized Precipitation Index (SPI) dataset. The synthesis examines past droughts classified into five categories: Meteorological, agricultural, hydrological, ecological, and socioeconomic drought. Results show that drought duration and magnitude have increased significantly, consistent …

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Optimizing Automated Kriging To Improve Spatial Interpolation Of Monthly Rainfall Over Complex Terrain, Matthew P. Lucas, Ryan J. Longman, Thomas W. Giambelluca, Abby G. Frazier, Jared Mclean, Sean B. Cleveland, Yu Fen Huang, Jonghyun Lee Apr 2022

Optimizing Automated Kriging To Improve Spatial Interpolation Of Monthly Rainfall Over Complex Terrain, Matthew P. Lucas, Ryan J. Longman, Thomas W. Giambelluca, Abby G. Frazier, Jared Mclean, Sean B. Cleveland, Yu Fen Huang, Jonghyun Lee

Geography

Gridded monthly rainfall estimates can be used for a number of research applications, including hydrologic modeling and weather forecasting. Automated interpolation algorithms, such as the "autoKrige" function in R, can produce gridded rainfall estimates that validate well but produce unrealistic spatial patterns. In this work, an optimized geostatistical kriging approach is used to interpolate relative rainfall anomalies, which are then combined with long-term means to develop the gridded estimates. The optimization consists of the following: 1) determining the most appropriate offset (constant) to use when log-transforming data; 2) eliminating poor quality data prior to interpolation; 3) detecting erroneous maps using …

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High Resolution, Annual Maps Of Field Boundaries For Smallholder-Dominated Croplands At National Scales, Lyndon D. Estes, Su Ye, Lei Song, Boka Luo, J. Ronald Eastman, Zhenhua Meng, Qi Zhang, Dennis Mcritchie, Stephanie R. Debats, Justus Muhando, Angeline H. Amukoa, Brian W. Kaloo, Jackson Makuru, Ben K. Mbatia, Isaac M. Muasa, Julius Mucha, Adelide M. Mugami, Judith M. Mugami, Francis W. Muinde, Fredrick M. Mwawaza, Jeff Ochieng, Charles J. Oduol, Purent Oduor, Thuo Wanjiku, Joseph G. Wanyoike, Ryan B. Avery, Kelly K. Caylor Feb 2022

High Resolution, Annual Maps Of Field Boundaries For Smallholder-Dominated Croplands At National Scales, Lyndon D. Estes, Su Ye, Lei Song, Boka Luo, J. Ronald Eastman, Zhenhua Meng, Qi Zhang, Dennis Mcritchie, Stephanie R. Debats, Justus Muhando, Angeline H. Amukoa, Brian W. Kaloo, Jackson Makuru, Ben K. Mbatia, Isaac M. Muasa, Julius Mucha, Adelide M. Mugami, Judith M. Mugami, Francis W. Muinde, Fredrick M. Mwawaza, Jeff Ochieng, Charles J. Oduol, Purent Oduor, Thuo Wanjiku, Joseph G. Wanyoike, Ryan B. Avery, Kelly K. Caylor

Geography

Mapping the characteristics of Africa’s smallholder-dominated croplands, including the sizes and numbers of fields, can provide critical insights into food security and a range of other socioeconomic and environmental concerns. However, accurately mapping these systems is difficult because there is 1) a spatial and temporal mismatch between satellite sensors and smallholder fields, and 2) a lack of high-quality labels needed to train and assess machine learning classifiers. We developed an approach designed to address these two problems, and used it to map Ghana’s croplands. To overcome the spatio-temporal mismatch, we converted daily, high resolution imagery into two cloud-free composites (the …

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Ten Facts About Land Systems For Sustainability, Patrick Meyfroidt, Ariane De Bremond, Casey M. Ryan, Emma Archer, Richard Aspinall, Abha Chhabra, Gilberto Camara, Rinku Roy Chowdhury, Esteve Corbera, Ruth Defries, Sandra Díaz, Jinwei Dong, Erle C. Ellis, Karl Heinz Erb, Janet A. Fisher, Rachael D. Garrett, Nancy E. Golubiewski, H. Ricardo Grau, J. Morgan Grove, Helmut Haberl, Andreas Heinimann, Patrick Hostert, Esteban G. Jobbágy, Suzi Kerr, Tobias Kuemmerle, Eric F. Lambin, Sandra Lavorel, Sharachandra Lele, Ole Mertz, Peter Messerli, Graciela Metternicht, Darla K. Munroe, Harini Nagendra Jan 2022

Ten Facts About Land Systems For Sustainability, Patrick Meyfroidt, Ariane De Bremond, Casey M. Ryan, Emma Archer, Richard Aspinall, Abha Chhabra, Gilberto Camara, Rinku Roy Chowdhury, Esteve Corbera, Ruth Defries, Sandra Díaz, Jinwei Dong, Erle C. Ellis, Karl Heinz Erb, Janet A. Fisher, Rachael D. Garrett, Nancy E. Golubiewski, H. Ricardo Grau, J. Morgan Grove, Helmut Haberl, Andreas Heinimann, Patrick Hostert, Esteban G. Jobbágy, Suzi Kerr, Tobias Kuemmerle, Eric F. Lambin, Sandra Lavorel, Sharachandra Lele, Ole Mertz, Peter Messerli, Graciela Metternicht, Darla K. Munroe, Harini Nagendra

Geography

Land use is central to addressing sustainability issues, including biodiversity conservation, climate change, food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard truths that have strong, general, empirical support. These facts help to explain the challenges of achieving sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and values of land are socially constructed and contested; 2) land systems exhibit complex behaviors with abrupt, hard-to-predict changes; 3) irreversible changes and path dependence …

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What Makes Wildfires Destructive In California?, Alexandra D. Syphard, Jon E. Keeley, Mike Gough, Mitchell Lazarz, John Rogan Jan 2022

What Makes Wildfires Destructive In California?, Alexandra D. Syphard, Jon E. Keeley, Mike Gough, Mitchell Lazarz, John Rogan

Geography

As human impacts from wildfires mount, there is a pressing need to understand why structures are lost in destructive fires. Despite growing research on factors contributing to structure loss, fewer studies have focused on why some fires are destructive and others are not. We characterized overall differences between fires that resulted in structure loss (“destructive fires”) and those that did not (“non-destructive wildfires”) across three California regions. Then, we performed statistical analyses on large fires only (≥100 ha) to distinguish the primary differences between large destructive large fires and large non-destructive fires. Overall, destructive fires were at least an order …

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