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Full-Text Articles in Physical Sciences and Mathematics

Changes At The Edge: Trends In Sea Ice, Ocean Temperature And Ocean Color At The Northwest Atlantic/Southern Arctic Interface, Ashley V. York, Karen E. Frey, Luisa N.C. Young Jan 2020

Changes At The Edge: Trends In Sea Ice, Ocean Temperature And Ocean Color At The Northwest Atlantic/Southern Arctic Interface, Ashley V. York, Karen E. Frey, Luisa N.C. Young

Geography

Spatial and temporal trends of remotely sensed sea-ice cover, sea surface temperatures, chlorophyll-a concentration and primary production in the Baffin Bay, Davis Strait and Labrador Sea were analyzed for the 1998-2017 period. We found spatial variability in the trends of these cryospheric, biologic and oceanographic phenomena. For example, in the northern Baffin Bay, we observed decreases in annual sea-ice persistence, yet increases along the Labrador Sea-ice edge during winter, with the latter having significant correlations with broader atmospheric patterns. In general, we observed increases in summer sea surface temperatures across the study region, except a small area of cooling along …


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 Jan 2018

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 …


Satellite-Based Estimates Of Antarctic Surface Meltwater Fluxes, Luke D. Trusel, Karen E. Frey, Sarah B. Das, Peter Kuipers Munneke, Michiel R. Van Den Broeke Jan 2013

Satellite-Based Estimates Of Antarctic Surface Meltwater Fluxes, Luke D. Trusel, Karen E. Frey, Sarah B. Das, Peter Kuipers Munneke, Michiel R. Van Den Broeke

Geography

This study generates novel satellite-derived estimates of Antarctic-wide annual (1999-2009) surface meltwater production using an empirical relationship between radar backscatter from the QuikSCAT (QSCAT) satellite and melt calculated from in situ energy balance observations. The resulting QSCAT-derived melt fluxes significantly agree with output from the regional climate model RACMO2.1 and with independent ground-based observations. The high-resolution (4.45 km) QSCAT-based melt fluxes uniquely detect interannually persistent and intense melt (>400 mm water equivalent (w.e.) year-1) on interior Larsen C Ice Shelf that is not simulated by RACMO2.1. This supports a growing understanding of the importance of a föhn effect in …


Antarctic Surface Melting Dynamics: Enhanced Perspectives From Radar Scatterometer Data, L. D. Trusel, K. E. Frey, S. B. Das Jan 2012

Antarctic Surface Melting Dynamics: Enhanced Perspectives From Radar Scatterometer Data, L. D. Trusel, K. E. Frey, S. B. Das

Geography

Antarctic ice sheet surface melting can regionally influence ice shelf stability, mass balance, and glacier dynamics, in addition to modulating near-surface physical and chemical properties over wide areas. Here, we investigate variability in surface melting from 1999 to 2009 using radar backscatter time series from the SeaWinds scatterometer aboard the QuikSCAT satellite. These daily, continent-wide observations are explored in concert with in situ meteorological records to validate a threshold-based melt detection method. Radar backscatter decreases during melting are significantly correlated with in situ positive degree-days as well as meltwater production determined from energy balance modeling at Neumayer Station, East Antarctica. …