Magnus Lund
Dados Biográficos
| ID | 6015174 |
|---|---|
| NOME | Magnus Lund |
| PRENOMES | Magnus |
| SOBRENOME | Lund |
| ASSINATURA | LUND M |
| AFILIAÇÕES | Aarhus University |
| ORCID | 0000-0003-1622-2305 |
| VERIFICADO | Sim |
| TOTAL DE OBRAS | 14 |
| TOTAL DE CITAÇÕES | 3 |
| TOTAL COMO AUTOR | 14 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 2012 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2020 |
| ÍNDICE H | 1 |
Shallow soils are warmer under trees and tall shrubs across Arctic and Boreal ecosystems
Soils are warming as air temperatures rise across the Arctic and Boreal region concurrent with the expansion of tall-statured shrubs and trees in the tundra. Changes in vegetation structure and function are expected to alter soil thermal regimes, thereby modifying climate feedbacks related to permafrost thaw and carbon cycling. However, current understanding of vegetation impacts on soil temperature is limited to local or regional scales and lack…
Key indicators of Arctic climate change
Key observational indicators of climate change in the Arctic, most spanning a 47 year period demonstrate fundamental changes among nine key elements of the Arctic system. We find that, coherent with increasing air temperature, there is an intensification of the hydrological cycle, evident from increases in humidity, precipitation, river discharge, glacier equilibrium line altitude and land ice wastage. Downward trends continue in sea ice thicknes…
Uncovering the unknown—climate interactions in a changing arctic tundra
Vulnerability and resilience of the carbon exchange of a subarctic peatland to an extreme winter event
Extreme winter events that damage vegetation are considered an important climatic cause of arctic\nbrowning—a reversal of the greening trend of the region—and possibly reduce the carbon uptake of\nnorthern ecosystems. Confirmation of a reduction in CO2 uptake due to winter damage, however,\nremains elusive due to a lack of flux measurements from affected ecosystems. In this study, we report\neddy covariance fluxes of CO2 from a peatland in northe…
Deltas, freshwater discharge, and waves along the Young Sound, NE Greenland
A wide range of delta morphologies occurs along the fringes of the Young Sound in Northeast Greenland due to spatial heterogeneity of delta regimes. In general, the delta regime is related to catchment and basin characteristics (geology, topography, drainage pattern, sediment availability, and bathymetry), fluvial discharges and associated sediment load, and processes by waves and currents. Main factors steering the Arctic fluvial discharges into…
Transitions in high-Arctic vegetation growth patterns and ecosystem productivity tracked with automated cameras from 2000 to 2013
Climate-induced changes in vegetation phenology at northern latitudes are still poorly understood. Continued monitoring and research are therefore needed to improve the understanding of abiotic drivers. Here we used 14 years of time lapse imagery and climate data from high-Arctic Northeast Greenland to assess the seasonal response of a dwarf shrub heath, grassland, and fen, to inter-annual variation in snow-cover, soil moisture, and air and soil …
Vegetation phenology gradients along the west and east coasts of Greenland from 2001 to 2015
The objective of this paper is to characterize the spatiotemporal variations of vegetation phenology along latitudinal and altitudinal gradients in Greenland, and to examine local and regional climatic drivers. Time-series from the Moderate Resolution Imaging Spectroradiometer (MODIS) were analyzed to obtain various phenological metrics for the period 2001-2015. MODIS-derived land surface temperatures were corrected for the sampling biases caused…
Towards quantifying the glacial runoff signal in the freshwater input to Tyrolerfjord–Young Sound, NE Greenland
Terrestrial freshwater runoff strongly influences physical and biogeochemical processes at the fjord scale and can have global impacts when considered at the Greenland scale. We investigate the performance of the HIRHAM5 regional climate model over the catchments delivering freshwater to Tyrolerfjord and Young Sound by comparing to the unique Greenland Ecological Monitoring database of in situ observations from this region. Based on these finding…
Hotspots and key periods of Greenland climate change during the past six decades
We investigated air temperature and pressure gradients and their trends for the period 1996-2014 in Greenland and compared these to other periods since 1958. Both latitudinal temperature and pressure gradients were strongest during winter. An overall temperature increase up to 0.15 °C year -1 was observed for 1996-2014. The strongest warming happened during February at the West coast (up to 0.6 °C year -1 ), weaker but consistent and significant …
Toward a statistical description of methane emissions from arctic wetlands
Methane (CH 4 ) emissions from arctic tundra typically follow relations with soil temperature and water table depth, but these process-based descriptions can be difficult to apply to areas where no measurements exist. We formulated a description of the broader temporal flux pattern in the growing season based on two distinct CH 4 source components from slow and fast-turnover carbon. We used automatic closed chamber flux measurements from NE Green…
Larval outbreaks in West Greenland
Insect outbreaks can have important consequences for tundra ecosystems. In this study, we synthesise available information on outbreaks of larvae of the noctuid moth Eurois occulta in Greenland. Based on an extensive dataset from a monitoring programme in Kobbefjord, West Greenland, we demonstrate effects of a larval outbreak in 2011 on vegetation productivity and CO 2 exchange. We estimate a decreased carbon (C) sink strength in the order of 118…
Spatiotemporal variability in surface energy balance across tundra, snow and ice in Greenland
The surface energy balance (SEB) is essential for understanding the coupled cryosphere-atmosphere system in the Arctic. In this study, we investigate the spatiotemporal variability in SEB across tundra, snow and ice. During the snow-free period, the main energy sink for ice sites is surface melt. For tundra, energy is used for sensible and latent heat flux and soil heat flux leading to permafrost thaw. Longer snow-free period increases melting of…
Low impact of dry conditions on the CO 2 exchange of a Northern-Norwegian blanket bog
Northern peatlands hold large amounts of organic carbon (C) in their soils and are as such important in a climate change context. Blanket bogs, i.e. nutrient-poor peatlands restricted to maritime climates, may be extra vulnerable to global warming since they require a positive water balance to sustain their moss dominated vegetation andCsink functioning. This study presents a 4.5 year record of land– atmosphere carbon dioxide (CO2) exchange from …
Effects of drought conditions on the carbon dioxide dynamics in a temperate peatland
Drought is arguably the most important regulator of inter-annual variation in net ecosystem CO exchange (NEE) in peatlands. This study investigates effects of drought periods on NEE and its components, gross primary production (GPP) and ecosystem respiration (R), on the basis of eddy covariance measurements of land-atmosphere exchange of CO in 2006-2009 in a south Swedish nutrient-poor peatland. Two drought periods had dissimilar effects on the C…
Transitions in high-Arctic vegetation growth patterns and ecosystem productivity tracked with automated cameras from 2000 to 2013
Climate-induced changes in vegetation phenology at northern latitudes are still poorly understood. Continued monitoring and research are therefore needed to improve the understanding of abiotic drivers. Here we used 14 years of time lapse imagery and climate data from high-Arctic Northeast Greenland to assess the seasonal response of a dwarf shrub heath, grassland, and fen, to inter-annual variation in snow-cover, soil moisture, and air and soil …
Vegetation phenology gradients along the west and east coasts of Greenland from 2001 to 2015
The objective of this paper is to characterize the spatiotemporal variations of vegetation phenology along latitudinal and altitudinal gradients in Greenland, and to examine local and regional climatic drivers. Time-series from the Moderate Resolution Imaging Spectroradiometer (MODIS) were analyzed to obtain various phenological metrics for the period 2001-2015. MODIS-derived land surface temperatures were corrected for the sampling biases caused…
Toward a statistical description of methane emissions from arctic wetlands
Methane (CH 4 ) emissions from arctic tundra typically follow relations with soil temperature and water table depth, but these process-based descriptions can be difficult to apply to areas where no measurements exist. We formulated a description of the broader temporal flux pattern in the growing season based on two distinct CH 4 source components from slow and fast-turnover carbon. We used automatic closed chamber flux measurements from NE Green…
Effects of drought conditions on the carbon dioxide dynamics in a temperate peatland
Drought is arguably the most important regulator of inter-annual variation in net ecosystem CO exchange (NEE) in peatlands. This study investigates effects of drought periods on NEE and its components, gross primary production (GPP) and ecosystem respiration (R), on the basis of eddy covariance measurements of land-atmosphere exchange of CO in 2006-2009 in a south Swedish nutrient-poor peatland. Two drought periods had dissimilar effects on the C…
Low impact of dry conditions on the CO 2 exchange of a Northern-Norwegian blanket bog
Northern peatlands hold large amounts of organic carbon (C) in their soils and are as such important in a climate change context. Blanket bogs, i.e. nutrient-poor peatlands restricted to maritime climates, may be extra vulnerable to global warming since they require a positive water balance to sustain their moss dominated vegetation andCsink functioning. This study presents a 4.5 year record of land– atmosphere carbon dioxide (CO2) exchange from …
Deltas, freshwater discharge, and waves along the Young Sound, NE Greenland
A wide range of delta morphologies occurs along the fringes of the Young Sound in Northeast Greenland due to spatial heterogeneity of delta regimes. In general, the delta regime is related to catchment and basin characteristics (geology, topography, drainage pattern, sediment availability, and bathymetry), fluvial discharges and associated sediment load, and processes by waves and currents. Main factors steering the Arctic fluvial discharges into…
Transitions in high-Arctic vegetation growth patterns and ecosystem productivity tracked with automated cameras from 2000 to 2013
Climate-induced changes in vegetation phenology at northern latitudes are still poorly understood. Continued monitoring and research are therefore needed to improve the understanding of abiotic drivers. Here we used 14 years of time lapse imagery and climate data from high-Arctic Northeast Greenland to assess the seasonal response of a dwarf shrub heath, grassland, and fen, to inter-annual variation in snow-cover, soil moisture, and air and soil …
Vegetation phenology gradients along the west and east coasts of Greenland from 2001 to 2015
The objective of this paper is to characterize the spatiotemporal variations of vegetation phenology along latitudinal and altitudinal gradients in Greenland, and to examine local and regional climatic drivers. Time-series from the Moderate Resolution Imaging Spectroradiometer (MODIS) were analyzed to obtain various phenological metrics for the period 2001-2015. MODIS-derived land surface temperatures were corrected for the sampling biases caused…
Towards quantifying the glacial runoff signal in the freshwater input to Tyrolerfjord–Young Sound, NE Greenland
Terrestrial freshwater runoff strongly influences physical and biogeochemical processes at the fjord scale and can have global impacts when considered at the Greenland scale. We investigate the performance of the HIRHAM5 regional climate model over the catchments delivering freshwater to Tyrolerfjord and Young Sound by comparing to the unique Greenland Ecological Monitoring database of in situ observations from this region. Based on these finding…
Hotspots and key periods of Greenland climate change during the past six decades
We investigated air temperature and pressure gradients and their trends for the period 1996-2014 in Greenland and compared these to other periods since 1958. Both latitudinal temperature and pressure gradients were strongest during winter. An overall temperature increase up to 0.15 °C year -1 was observed for 1996-2014. The strongest warming happened during February at the West coast (up to 0.6 °C year -1 ), weaker but consistent and significant …
Toward a statistical description of methane emissions from arctic wetlands
Methane (CH 4 ) emissions from arctic tundra typically follow relations with soil temperature and water table depth, but these process-based descriptions can be difficult to apply to areas where no measurements exist. We formulated a description of the broader temporal flux pattern in the growing season based on two distinct CH 4 source components from slow and fast-turnover carbon. We used automatic closed chamber flux measurements from NE Green…
Larval outbreaks in West Greenland
Insect outbreaks can have important consequences for tundra ecosystems. In this study, we synthesise available information on outbreaks of larvae of the noctuid moth Eurois occulta in Greenland. Based on an extensive dataset from a monitoring programme in Kobbefjord, West Greenland, we demonstrate effects of a larval outbreak in 2011 on vegetation productivity and CO 2 exchange. We estimate a decreased carbon (C) sink strength in the order of 118…
Spatiotemporal variability in surface energy balance across tundra, snow and ice in Greenland
The surface energy balance (SEB) is essential for understanding the coupled cryosphere-atmosphere system in the Arctic. In this study, we investigate the spatiotemporal variability in SEB across tundra, snow and ice. During the snow-free period, the main energy sink for ice sites is surface melt. For tundra, energy is used for sensible and latent heat flux and soil heat flux leading to permafrost thaw. Longer snow-free period increases melting of…
Uncovering the unknown—climate interactions in a changing arctic tundra
Vulnerability and resilience of the carbon exchange of a subarctic peatland to an extreme winter event
Extreme winter events that damage vegetation are considered an important climatic cause of arctic\nbrowning—a reversal of the greening trend of the region—and possibly reduce the carbon uptake of\nnorthern ecosystems. Confirmation of a reduction in CO2 uptake due to winter damage, however,\nremains elusive due to a lack of flux measurements from affected ecosystems. In this study, we report\neddy covariance fluxes of CO2 from a peatland in northe…
Key indicators of Arctic climate change
Key observational indicators of climate change in the Arctic, most spanning a 47 year period demonstrate fundamental changes among nine key elements of the Arctic system. We find that, coherent with increasing air temperature, there is an intensification of the hydrological cycle, evident from increases in humidity, precipitation, river discharge, glacier equilibrium line altitude and land ice wastage. Downward trends continue in sea ice thicknes…
Shallow soils are warmer under trees and tall shrubs across Arctic and Boreal ecosystems
Soils are warming as air temperatures rise across the Arctic and Boreal region concurrent with the expansion of tall-statured shrubs and trees in the tundra. Changes in vegetation structure and function are expected to alter soil thermal regimes, thereby modifying climate feedbacks related to permafrost thaw and carbon cycling. However, current understanding of vegetation impacts on soil temperature is limited to local or regional scales and lack…
Environmental Science (13 obras) · Climate change and permafrost (12 obras) · Ecology (12 obras) · Geography (12 obras) · Geology (11 obras) · Cryospheric studies and observations (10 obras) · Physical geography (10 obras) · Biology (8 obras) · Oceanography (8 obras) · Arctic (7 obras)