Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Sea ice (7)
- Climate change (5)
- Chukchi Sea (3)
- Climate (3)
- Resilience (3)
-
- Air-sea interaction (2)
- Arctic (2)
- Arctic Ocean (2)
- Bering Sea (2)
- Carbon cycle (2)
- Carbon dioxide (2)
- Chlorophyll (2)
- Dendroctonus rufipennis (2)
- Drought (2)
- Gas exchange (2)
- Ice cover (2)
- Infrastructure (2)
- Landscape (2)
- Marine ecosystems (2)
- Photodegradation (2)
- Picea engelmannii (2)
- Absorption (1)
- Adaptation (1)
- Air temperature (1)
- Altitude (1)
- Animal (1)
- Annual variation (1)
- Anthropogenic effect (1)
- Aquatic organism (1)
- ArcGIS Online (1)
- Publication
- Publication Type
Articles 1 - 26 of 26
Full-Text Articles in Climate
Phytoplankton Bloom Stages Estimated From Chlorophyll Pigment Proportions Suggest Delayed Summer Production In Low Sea Ice Years In The Northern Bering Sea, Clare B. Gaffey, Karen E. Frey, Lee W. Cooper, Jacqueline M. Grebmeier
Phytoplankton Bloom Stages Estimated From Chlorophyll Pigment Proportions Suggest Delayed Summer Production In Low Sea Ice Years In The Northern Bering Sea, Clare B. Gaffey, Karen E. Frey, Lee W. Cooper, Jacqueline M. Grebmeier
Geography
Decreased sea ice cover in the northern Bering Sea has altered annual phytoplankton phenology owing to an expansion of open water duration and its impact on ocean stratification. Limitations of satellite remote sensing such as the inability to detect bloom activity throughout the water column, under ice, and in cloudy conditions dictate the need for shipboard based measurements to provide more information on bloom dynamics. In this study, we adapted remote sensing land cover classification techniques to provide a new means to determine bloom stage from shipboard samples. Specifically, we used multiyear satellite time series of chlorophyll a to determine …
Sidebar: Observations Of Declining Primary Productivity In The Western Bering Strait, Karen E. Frey, Jaclyn Clement Kinney, Larry V. Stock, Robert Osinski
Sidebar: Observations Of Declining Primary Productivity In The Western Bering Strait, Karen E. Frey, Jaclyn Clement Kinney, Larry V. Stock, Robert Osinski
Geography
No abstract provided.
Climate Adaptation For Tropical Island Land Stewardship: Adapting A Workshop Planning Process To Hawai'i, Ryan J. Longman, Courtney L. Peterson, Madeline Baroli, Abby G. Frazier, Zachary Cook, Elliott W. Parsons, Maude Dinan, Katie L. Kamelamela, Caitriana Steele, Reanna Burnett, Chris Swanston, Christian P. Giardina
Climate Adaptation For Tropical Island Land Stewardship: Adapting A Workshop Planning Process To Hawai'i, Ryan J. Longman, Courtney L. Peterson, Madeline Baroli, Abby G. Frazier, Zachary Cook, Elliott W. Parsons, Maude Dinan, Katie L. Kamelamela, Caitriana Steele, Reanna Burnett, Chris Swanston, Christian P. Giardina
Geography
No abstract provided.
The Pacific Drought Knowledge Exchange: A Co-Production Approach To Deliver Climate Resources To User Groups, Ryan J. Longman, Abby G. Frazier, Christian P. Giardina, Elliott W. Parsons, Sierra Mcdaniel
The Pacific Drought Knowledge Exchange: A Co-Production Approach To Deliver Climate Resources To User Groups, Ryan J. Longman, Abby G. Frazier, Christian P. Giardina, Elliott W. Parsons, Sierra Mcdaniel
Geography
Drought is a growing threat to hydrological, ecological, agricultural, and socio-cultural systems of the tropics, especially tropical islands of the Pacific where severe droughts can compromise food and water security. Overcoming barriers to knowledge sharing between land managers and researchers is a critical cross-sector strategy for engaging and mitigating or adapting to drought. Here we describe the establishment and functioning of the Pacific Drought Knowledge Exchange (PDKE), which provides users with easier access to: (1) sector- and geography-specific climate information; (2) better and more comprehensive information; (3) improved technical assistance; and (4) a more collaborative information-transfer environment through participation in …
Application Of Autoencoders For Latent Pattern Analysis In Image Time Series, Jiena He
Application Of Autoencoders For Latent Pattern Analysis In Image Time Series, Jiena He
Sustainability and Social Justice
The Earth system is considered to possess certain modes - preferred patterns of variability that can represent the latent structure of the climate system, also known as teleconnections. There are approaches to discover these patterns, Principal Components Analysis and Empirical Orthogonal Teleconnection (EOT) analysis. However, while the latter is very effective, it is computationally intensive. An autoencoder is an unsupervised neural network that learns an efficient neural representation of input data. It is considered as a dimensionality reduction tool that is highly similar to PCA and EOT. The hidden layer of an autoencoder represents the most significant information of the …
Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D’Amato, Tiphaine Després, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Álvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, Thomas Kitzberger, Dominik Kulakowski, David Lindenmayer, Akira S. Mori, Jörg Müller, Juan Paritsis, George L.W. Perry, Scott L. Stephens, Miroslav Svoboda, Monica G. Turner, Thomas T. Veblen, Rupert Seidl
Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D’Amato, Tiphaine Després, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Álvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, Thomas Kitzberger, Dominik Kulakowski, David Lindenmayer, Akira S. Mori, Jörg Müller, Juan Paritsis, George L.W. Perry, Scott L. Stephens, Miroslav Svoboda, Monica G. Turner, Thomas T. Veblen, Rupert Seidl
Geography
Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and …
Unraveling Phytoplankton Community Dynamics In The Northern Chukchi Sea Under Sea-Ice-Covered And Sea-Ice-Free Conditions, A. R. Neeley, L. A. Harris, K. E. Frey
Unraveling Phytoplankton Community Dynamics In The Northern Chukchi Sea Under Sea-Ice-Covered And Sea-Ice-Free Conditions, A. R. Neeley, L. A. Harris, K. E. Frey
Geography
The timing of sea ice retreat, light availability, and sea surface stratification largely control the phytoplankton community composition in the Chukchi Sea. This region is experiencing a significant warming trend, an overall decrease in sea ice cover, and a documented decline in annual sea ice persistence and thickness over the past several decades. The consequences of earlier seasonal sea ice retreat and a longer sea-ice-free season on phytoplankton community composition warrant investigation. We applied multivariate statistical techniques to elucidate the mechanisms that relate environmental variables to phytoplankton community composition in the Chukchi Sea using data collected during a single field …
(Un)Frozen Spaces: Exploring The Role Of Sea Ice In The Marine Socio-Legal Spaces Of The Bering And Beaufort Seas, Kristen L. Shake, Karen E. Frey, Deborah G. Martin, Philip E. Steinberg
(Un)Frozen Spaces: Exploring The Role Of Sea Ice In The Marine Socio-Legal Spaces Of The Bering And Beaufort Seas, Kristen L. Shake, Karen E. Frey, Deborah G. Martin, Philip E. Steinberg
Geography
Sea ice is a dynamic physical element of the greater Arctic marine system, one that has myriad connections to human systems on a variety of spatial and temporal scales. Changes to the spatial extent of sea ice simultaneously permits and endangers maritime operations, as well as impacts current debates over maritime boundaries, presenting an interesting challenge for international law. Sea ice is not a stationary object; it moves through time and space in response to the physical forces of wind, ocean currents, and heating. It has a tangible, material and substantive role in contestations over territory, resources and marine boundaries …
Trends In Benthic Macrofaunal Populations, Seasonal Sea Ice Persistence, And Bottom Water Temperatures In The Bering Strait Region, Jacqueline M. Grebmeier, Karen E. Frey, Lee W. Cooper, Monika Kędra
Trends In Benthic Macrofaunal Populations, Seasonal Sea Ice Persistence, And Bottom Water Temperatures In The Bering Strait Region, Jacqueline M. Grebmeier, Karen E. Frey, Lee W. Cooper, Monika Kędra
Geography
Recent declines in sea ice extent and warming seawater temperatures in the Arctic have the potential to impact regional and pan-Arctic marine ecosystems. To investigate marine biological response to these key drivers and other environmental factors, we undertook a robust trend analysis of benthic macrofaunal populations and environmental drivers in the Bering Strait region. Our focus was on the waters of the northern Bering and southern Chukchi Seas, which are shallow (m) and seasonally productive, with strong pelagic-benthic coupling between water-column-derived organic matter and the seafloor. Studies indicate that both in situ production and advection of upstream phytodetritus support persistent …
Data Descriptor: Compilation Of Climate Data From Heterogeneous Networks Across The Hawaiian Islands, Ryan J. Longman, Thomas W. Giambelluca, Michael A. Nullet, Abby G. Frazier, Kevin Kodama, Shelley D. Crausbay, Paul D. Krushelnycky, Susan Cordell, Martyn P. Clark, Andy J. Newman, Jeffrey R. Arnold
Data Descriptor: Compilation Of Climate Data From Heterogeneous Networks Across The Hawaiian Islands, Ryan J. Longman, Thomas W. Giambelluca, Michael A. Nullet, Abby G. Frazier, Kevin Kodama, Shelley D. Crausbay, Paul D. Krushelnycky, Susan Cordell, Martyn P. Clark, Andy J. Newman, Jeffrey R. Arnold
Geography
Long-term, accurate observations of atmospheric phenomena are essential for a myriad of applications, including historic and future climate assessments, resource management, and infrastructure planning. In Hawai'i, climate data are available from individual researchers, local, State, and Federal agencies, and from large electronic repositories such as the National Centers for Environmental Information (NCEI). Researchers attempting to make use of available data are faced with a series of challenges that include: (1) identifying potential data sources; (2) acquiring data; (3) establishing data quality assurance and quality control (QA/QC) protocols; and (4) implementing robust gap filling techniques. This paper addresses these challenges by …
Resource Extraction And Infrastructure Threaten Forest Cover And Community Rights, Anthony J. Bebbington, Denise Humphreys Bebbington, Laura Aileen Sauls, John Rogan, Sumali Agrawal, César Gamboa, Aviva Imhof, Kimberly Johnson, Herman Rosa, Antoinette Royo, Tessa Toumbourou, Ricardo Verdum
Resource Extraction And Infrastructure Threaten Forest Cover And Community Rights, Anthony J. Bebbington, Denise Humphreys Bebbington, Laura Aileen Sauls, John Rogan, Sumali Agrawal, César Gamboa, Aviva Imhof, Kimberly Johnson, Herman Rosa, Antoinette Royo, Tessa Toumbourou, Ricardo Verdum
Geography
Mineral and hydrocarbon extraction and infrastructure are increasingly significant drivers of forest loss, greenhouse gas emissions, and threats to the rights of forest communities in forested areas of Amazonia, Indonesia, and Mesoamerica. Projected investments in these sectors suggest that future threats to forests and rights are substantial, particularly because resource extraction and infrastructure reinforce each other and enable population movements and agricultural expansion further into the forest. In each region, governments have made framework policy commitments to national and cross-border infrastructure integration, increased energy production, and growth strategies based on further exploitation of natural resources. This reflects political settlements among …
A Walk On The Wild Side: Disturbance Dynamics And The Conservation And Management Of European Mountain Forest Ecosystems, Dominik Kulakowski, Rupert Seidl, Jan Holeksa, Timo Kuuluvainen, Thomas A. Nagel, Momchil Panayotov, Miroslav Svoboda, Simon Thorn, Giorgio Vacchiano, Cathy Whitlock, Thomas Wohlgemuth, Peter Bebi
A Walk On The Wild Side: Disturbance Dynamics And The Conservation And Management Of European Mountain Forest Ecosystems, Dominik Kulakowski, Rupert Seidl, Jan Holeksa, Timo Kuuluvainen, Thomas A. Nagel, Momchil Panayotov, Miroslav Svoboda, Simon Thorn, Giorgio Vacchiano, Cathy Whitlock, Thomas Wohlgemuth, Peter Bebi
Geography
Mountain forests are among the most important ecosystems in Europe as they support numerous ecological, hydrological, climatic, social, and economic functions. They are unique relatively natural ecosystems consisting of long-lived species in an otherwise densely populated human landscape. Despite this, centuries of intensive forest management in many of these forests have eclipsed evidence of natural processes, especially the role of disturbances in long-term forest dynamics. Recent trends of land abandonment and establishment of protected forests have coincided with a growing interest in managing forests in more natural states. At the same time, the importance of past disturbances highlighted in an …
Is Initial Post-Disturbance Regeneration Indicative Of Longer-Term Trajectories?, Nathan S. Gill, Daniel Jarvis, Thomas T. Veblen, Steward T.A. Pickett, Dominik Kulakowski
Is Initial Post-Disturbance Regeneration Indicative Of Longer-Term Trajectories?, Nathan S. Gill, Daniel Jarvis, Thomas T. Veblen, Steward T.A. Pickett, Dominik Kulakowski
Geography
The ability to estimate and model future vegetation dynamics is a central focus of contemporary ecology and is essential for understanding future ecological trajectories. It is therefore critical to understand when the influence of initial post-disturbance regeneration versus stochastic processes dominates long-term post-disturbance ecological processes. Often, conclusions about post-disturbance dynamics are based upon initial regeneration in the years immediately after disturbances. However, the degree to which initial post-disturbance regeneration indicates longer-term trends is likely to be contingent on the types, intensities, and combinations of disturbances, as well as pre-disturbance ecosystem structure and composition. Our relatively limited understanding of why initial …
Summer 2015 Internship: Enterprise Gis Support For The National Audubon Society, Monica Noon
Summer 2015 Internship: Enterprise Gis Support For The National Audubon Society, Monica Noon
Sustainability and Social Justice
From May to August 2015, I worked with the National Audubon Society as an Enterprise GIS Support Intern, under the supervision of Doreen Whitley Rogers. I assisted the department with the GIS help desk requests and supported ArcGIS users with project assistance and training. This report summarizes the structure of the organization, my role as an Enterprise GIS Support Intern and my assessment and reflection of my experience.
Optical Properties And Bioavailability Of Dissolved Organic Matter Along A Flow-Path Continuum From Soil Pore Waters To The Kolyma River Mainstem, East Siberia, Karen E. Frey, William V. Sobczak, Paul J. Mann, Robert M. Holmes
Optical Properties And Bioavailability Of Dissolved Organic Matter Along A Flow-Path Continuum From Soil Pore Waters To The Kolyma River Mainstem, East Siberia, Karen E. Frey, William V. Sobczak, Paul J. Mann, Robert M. Holmes
Geography
The Kolyma River in northeast Siberia is among the six largest Arctic rivers and drains a region underlain by vast deposits of Holocene-aged peat and Pleistocene-aged loess known as yedoma, most of which is currently stored in ice-rich permafrost throughout the region. These peat and yedoma deposits are important sources of dissolved organic matter (DOM) to inland waters that in turn play a significant role in the transport and ultimate remineralization of organic carbon to CO2 and CH4 along the terrestrial flow-path continuum. The turnover and fate of terrigenous DOM during offshore transport largely depends upon the composition and amount …
Decadal Bering Sea Seascape Change: Consequences For Pacific Walruses And Indigenous Hunters, G. Carleton Ray, Gary L. Hufford, James E. Overland, Igor Krupnik, Jerry Mccormick-Ray, Karen Frey, Elizabeth Labunski
Decadal Bering Sea Seascape Change: Consequences For Pacific Walruses And Indigenous Hunters, G. Carleton Ray, Gary L. Hufford, James E. Overland, Igor Krupnik, Jerry Mccormick-Ray, Karen Frey, Elizabeth Labunski
Geography
The most signifi cant factors currently affecting the Pacifi c walrus (Odobenus rosmarus divergens) population are climate change and consequent changes in sea-ice morphology and dynamics. This paper integrates recent physical sea-ice change in the Bering Sea with biological and ecological conditions of walruses in their winter-spring reproductive habitat. Historically, walrus in winter-spring depended on a critical mass of sea-ice habitat to optimize social networking, reproductive fi tness, feeding behavior, migration, and energetic effi ciency. During 2003-2013, our cross-disciplinary, multiscale analysis from shipboard observations, satellite imagery, and ice-fl oe tracking, reinforced by information from indigenous subsistence hunters, documented change of …
Not Only Climate: Interacting Drivers Of Treeline Change In Europe, Dominik Kulakowski, Ignacio Barbeito, Alejandro Casteller, Ryszard J. Kaczka, Peter Bebi
Not Only Climate: Interacting Drivers Of Treeline Change In Europe, Dominik Kulakowski, Ignacio Barbeito, Alejandro Casteller, Ryszard J. Kaczka, Peter Bebi
Geography
Treelines have long been recognized as important ecotones and likely harbingers of climate change. However, over the last century many treelines have been affected not only by global warming, but also by the interactions of climate, forest disturbance and the consequences of abrupt demographic and economic changes. Recent research has increasingly stressed how multiple ecological, biophysical, and human factors interact to shape ecological dynamics. Here we highlight the need to consider interactions among multiple drivers to more completely understand and predict treeline dynamics in Europe.
Mining, Risk And Climate Resilience In The 'Other' Pacific: Latin American Lessons For The South Pacific, Anthony J. Bebbington, Jeffrey Bury, Nicholas Cuba, John Rogan
Mining, Risk And Climate Resilience In The 'Other' Pacific: Latin American Lessons For The South Pacific, Anthony J. Bebbington, Jeffrey Bury, Nicholas Cuba, John Rogan
Geography
We suggest the value of considering Pacific Latin America and the South Pacific in relationship to each other in contexts of climate change and investment in extractive industry. The paper explores the interactions between extractive industry, climate change and environmental governance through the lenses of double exposure, double movements, resilience and risk. The first part of the paper addresses the nature and scope of investments in extractive industries in this 'other Pacific'. The geography of these investments is changing the actual and perceived distribution of exposure and risk in the region. The nature of this risk is also being affected …
Large Carbon Release Legacy From Bark Beetle Outbreaks Across Western United States, Bardan Ghimire, Christopher A. Williams, G. James Collatz, Melanie Vanderhoof, John Rogan, Dominik Kulakowski, Jeffrey G. Masek
Large Carbon Release Legacy From Bark Beetle Outbreaks Across Western United States, Bardan Ghimire, Christopher A. Williams, G. James Collatz, Melanie Vanderhoof, John Rogan, Dominik Kulakowski, Jeffrey G. Masek
Geography
Warmer conditions over the past two decades have contributed to rapid expansion of bark beetle outbreaks killing millions of trees over a large fraction of western United States (US) forests. These outbreaks reduce plant productivity by killing trees and transfer carbon from live to dead pools where carbon is slowly emitted to the atmosphere via heterotrophic respiration which subsequently feeds back to climate change. Recent studies have begun to examine the local impacts of bark beetle outbreaks in individual stands, but the full regional carbon consequences remain undocumented for the western US. In this study, we quantify the regional carbon …
Interactions Among Spruce Beetle Disturbance, Climate Change And Forest Dynamics Captured By A Forest Landscape Model, Christian Temperli, Thomas T. Veblen, Sarah J. Hart, Dominik Kulakowski, Alan J. Tepley
Interactions Among Spruce Beetle Disturbance, Climate Change And Forest Dynamics Captured By A Forest Landscape Model, Christian Temperli, Thomas T. Veblen, Sarah J. Hart, Dominik Kulakowski, Alan J. Tepley
Geography
The risk of bark beetle outbreaks is widely predicted to increase because of a warming climate that accelerates temperature-driven beetle population growth and drought stress that impairs host tree defenses. However, few if any studies have explicitly evaluated climatically enhanced beetle population dynamics in relation to climate-driven changes in forest composition and structure that may alter forest suitability for beetle infestation. We synthesized current understanding of the interactions among climate, spruce beetles (Dendroctonus rufipennis) and forest dynamics to parameterize and further advance the bark beetle module of a dynamic forest landscape model (LandClim) that also integrates fire and wind disturbance …
Assessing The Potential Impacts Of Declining Arctic Sea Ice Cover On The Photochemical Degradation Of Dissolved Organic Matter In The Chukchi And Beaufort Seas, Christie L. Logvinova, Karen E. Frey, Paul J. Mann, Aron Stubbins, Robert G.M. Spencer
Assessing The Potential Impacts Of Declining Arctic Sea Ice Cover On The Photochemical Degradation Of Dissolved Organic Matter In The Chukchi And Beaufort Seas, Christie L. Logvinova, Karen E. Frey, Paul J. Mann, Aron Stubbins, Robert G.M. Spencer
Geography
A warming and shifting climate in the Arctic has led to significant declines in sea ice over the last several decades. Although these changes in sea ice cover are well documented, large uncertainties remain in how associated increases in solar radiation transmitted to the underlying ocean water column will impact heating, biological, and biogeochemical processes in the Arctic Ocean. In this study, six under-ice marine, two ice-free marine, and two ice-free terrestrially influenced water samples were irradiated using a solar simulator for 72 h (representing ~10 days of ambient sunlight) to investigate dissolved organic matter (DOM) dynamics from the Chukchi …
Sea-Air Co2 Exchange In The Western Arctic Coastal Ocean, Wiley Evans, Jeremy T. Mathis, Jessica N. Cross, Nicholas R. Bates, Karen E. Frey, Brent G.T. Else, Tim N. Papkyriakou, Mike D. Degrandpre, Fakhrul Islam, Wei Jun Cai, Baoshan Chen, Michiyo Yamamoto-Kawai, Eddy Carmack, William J. Williams, Taro Takahashi
Sea-Air Co2 Exchange In The Western Arctic Coastal Ocean, Wiley Evans, Jeremy T. Mathis, Jessica N. Cross, Nicholas R. Bates, Karen E. Frey, Brent G.T. Else, Tim N. Papkyriakou, Mike D. Degrandpre, Fakhrul Islam, Wei Jun Cai, Baoshan Chen, Michiyo Yamamoto-Kawai, Eddy Carmack, William J. Williams, Taro Takahashi
Geography
The biogeochemical seascape of the western Arctic coastal ocean is in rapid transition. Changes in sea ice cover will be accompanied by alterations in sea-air carbon dioxide (CO2) exchange, of which the latter has been difficult to constrain owing to sparse temporal and spatial data sets. Previous assessments of sea-air CO2 flux have targeted specific subregional areas of the western Arctic coastal ocean. Here a holistic approach is taken to determine the net sea-air CO2 flux over this broad region. We compiled and analyzed an extensive data set of nearly 600,000 surface seawater CO2 partial pressure (pCO2) measurements spanning 2003 …
Negative Feedbacks On Bark Beetle Outbreaks: Widespread And Severe Spruce Beetle Infestation Restricts Subsequent Infestation, Sarah J. Hart, Thomas T. Veblen, Nathan Mietkiewicz, Dominik Kulakowski
Negative Feedbacks On Bark Beetle Outbreaks: Widespread And Severe Spruce Beetle Infestation Restricts Subsequent Infestation, Sarah J. Hart, Thomas T. Veblen, Nathan Mietkiewicz, Dominik Kulakowski
Geography
Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced …
Sea-Ice Melt Co2-Carbonate Chemistry In The Western Arctic Ocean: Meltwater Contributions To Air-Sea Co2 Gas Exchange, Mixed-Layer Properties And Rates Of Net Community Production Under Sea Ice, N. R. Bates, R. Garley, K. E. Frey, K. L. Shake, J. T. Mathis
Sea-Ice Melt Co2-Carbonate Chemistry In The Western Arctic Ocean: Meltwater Contributions To Air-Sea Co2 Gas Exchange, Mixed-Layer Properties And Rates Of Net Community Production Under Sea Ice, N. R. Bates, R. Garley, K. E. Frey, K. L. Shake, J. T. Mathis
Geography
The carbon dioxide (CO2)-carbonate chemistry of sea-ice melt and co-located, contemporaneous seawater has rarely been studied in sea-ice-covered oceans. Here, we describe the CO2-carbonate chemistry of sea-ice melt (both above sea-ice as "melt ponds" and below sea-ice as "interface waters") and mixed-layer properties in the western Arctic Ocean in the early summer of 2010 and 2011. At 19 stations, the salinity (∼0.5 to <6.5), dissolved inorganic carbon (DIC; ∼20 to <550 μmol kg-1) and total alkalinity (TA; ∼30 to <500 μmol kg-1) of above-ice melt pond water was low compared to the co-located underlying mixed layer. The partial pressure of CO2 (pCO2) in these melt ponds was highly variable (∼<10 to >1500 μatm) with the majority of melt ponds acting as potentially strong sources of CO2 to the atmosphere. The pH of melt pond waters was also highly variable ranging from mildly acidic (6.1 to 7) to slightly …
Annual Sea-Air Co2 Fluxes In The Bering Sea: Insights From New Autumn And Winter Observations Of A Seasonally Ice-Covered Continental Shelf, Jessica N. Cross, Jeremy T. Mathis, Karen E. Frey, Catherine E. Cosca, Seth L. Danielson, Nicholas R. Bates, Richard A. Feely, Taro Takahashi, Wiley Evans
Annual Sea-Air Co2 Fluxes In The Bering Sea: Insights From New Autumn And Winter Observations Of A Seasonally Ice-Covered Continental Shelf, Jessica N. Cross, Jeremy T. Mathis, Karen E. Frey, Catherine E. Cosca, Seth L. Danielson, Nicholas R. Bates, Richard A. Feely, Taro Takahashi, Wiley Evans
Geography
High-resolution data collected from several programs have greatly increased the spatiotemporal resolution of pCO2(sw) data in the Bering Sea, and provided the first autumn and winter observations. Using data from 2008 to 2012, monthly climatologies of sea-air CO2 fluxes for the Bering Sea shelf area from April to December were calculated, and contributions of physical and biological processes to observed monthly sea-air pCO2 gradients (ΔpCO2) were investigated. Net efflux of CO2 was observed during November, December, and April, despite the impact of sea surface cooling on ΔpCO2. Although the Bering Sea was believed to be a moderate to strong atmospheric …
A Synthesis Of The Long-Term Paleoclimatic Evolution Of The Arctic, Matthew O'Regan, Christopher J. Williams, Karen E. Frey, Martin Jakobsson
A Synthesis Of The Long-Term Paleoclimatic Evolution Of The Arctic, Matthew O'Regan, Christopher J. Williams, Karen E. Frey, Martin Jakobsson
Geography
Since the Arctic Ocean began forming in the Early Cretaceous 112-140 million years ago, the Arctic region has undergone profound oceanographic and paleoclimatic changes. It has evolved from a warm epicontinental sea to its modern state as a cold isolated ocean with extensive perennial sea ice cover. Our understanding of the long-term paleoclimate evolution of the Arctic remains fragmentary but has advanced dramatically in the past decade through analysis of new marine and terrestrial records, supplemented by important insights from paleoclimate models. Improved understanding of how these observations fit into the long-term evolution of the global climate system requires additional …