scholarly journals Simulating a Warmer, Drier Arctic

Eos ◽  
2015 ◽  
Vol 96 ◽  
Author(s):  
Kate Wheeling
Keyword(s):  
Field Experiments ◽  
Carbon Dynamics ◽  
The Arctic

Field experiments examine the effect of rising temperatures and drying soils on carbon dynamics in the Arctic.

Coupling of nutrient cycling and carbon dynamics in the Arctic, integration of soil microbial and plant processes

1999 ◽  
Vol 11 (2-3) ◽  
pp. 135-146 ◽  
Author(s):  
Sven Jonasson ◽  
Anders Michelsen ◽  
Inger K Schmidt
Keyword(s):  
Nutrient Cycling ◽  
Carbon Dynamics ◽  
The Arctic ◽  
Soil Microbial

Biological and Biotechnological Evaluation of Carbon Dynamics in Field Experiments

2011 ◽  
pp. 209-228
Author(s):  
Carmine Crecchio ◽  
Silvia Pascazio ◽  
Pacifico Ruggiero
Keyword(s):  
Field Experiments ◽  
Carbon Dynamics

scholarly journals Vertical structure of Antarctic tropospheric ozone depletion events: characteristics and broader implications

2010 ◽  
Vol 10 (3) ◽  
pp. 8189-8246 ◽  
Author(s):  
A. E. Jones ◽  
P. S. Anderson ◽  
E. W. Wolff ◽  
H. K. Roscoe ◽  
G. J. Marshall ◽  
...  
Keyword(s):  
High Altitude ◽  
Ozone Depletion ◽  
Tropospheric Ozone ◽  
Large Scale ◽  
Field Experiments ◽  
Strong Association ◽  
Vertical Component ◽  
Low Pressure ◽  
The Arctic ◽  
Low Pressure Systems

Abstract. The majority of tropospheric ozone depletion event (ODE) studies have focussed on time-series measurements, with comparatively few studies of the vertical component. Those that exist have almost exclusively used free-flying balloon-borne ozonesondes and almost all have been conducted in the Arctic. Here we use measurements from two separate Antarctic field experiments to examine the vertical profile of ozone during Antarctic ODEs. We use tethersonde data to probe details in the lowest few hundred meters and find considerable structure in the profiles associated with complex atmospheric layering. The profiles were all measured at wind speeds less than 7 ms−1, and on each occasion the lowest inversion height lay between 10 m and 40 m. We also use data from a free-flying ozonesonde study to select events where ozone depletion was recorded at altitudes >1 km above ground level. Using ERA-40 meteorological charts, we find that on every occasion the high altitude depletion was preceded by an atmospheric low pressure system. An examination of limited published ozonesonde data from other Antarctic stations shows this to be a consistent feature. Given the link between BrO and ODEs, we also examine ground-based and satellite BrO measurements, and find a strong association between enhanced BrO and atmospheric low pressure systems. The results suggest that, in Antarctica, such depressions are responsible for driving high altitude ODEs and for generating the large-scale BrO clouds observed from satellites. In the Arctic, the prevailing meteorology differs from that in Antarctica, but we show that major low pressure systems in the Arctic, when they occur, can also generate BrO clouds. Such depressions thus appear to be fundamental when considering the broader influence of ODEs, particularly in Antarctica, such as halogen export and the radiative influence of ozone-depleted air masses.

Boreal Vegetation and Soil Carbon Dynamics in Response to a Changing Climate and Soil Variables

2021 ◽  
Author(s):  
John Galbraith ◽  
Pavel Krasilnikov ◽  
Cornelia Rumpel
Keyword(s):  
Boreal Forest ◽  
Vegetation Change ◽  
Precipitation Amount ◽  
Carbon Dynamics ◽  
The Arctic ◽  
Higher Plant ◽  
Rock Fragments ◽  
Changing Climate ◽  
Soil Variables ◽  
Air Temperatures

<p>Many soils in the Boreal forest regions of the Arctic store very large amounts of carbon in the active layer above permafrost, and store significant amounts of carbon within the permafrost. Soils that are well drained, high in rock fragments, shallow to rock or rubble, or covered with ice are exceptions. No other region on Earth stores more carbon on average than the Arctic regions, especially in wetlands. However, changes in vegetation and soil are expected under warming climates. Research questions have arisen about future changes in vegetation and net carbon flux as soil and air temperatures climb, as precipitation amount and type changes, and as the growing season lengthens. A review of recent literature will be conducted to look at effects of vegetation change and annual carbon dynamics in Boreal forest and wetland soils under warming climates. Environmental variables such as soil temperature, hydrology, microbial and higher plant growth, digestibility of young and old carbon, fire, location zone, extent and type of permafrost thaw slow vs sudden collapse), and N and P nutrient balances will affect carbon stocks in addition to changing climate.</p>

SVALBARD 2006 EXPERIMENTAL OIL SPILL UNDER ICE: REMOTE SENSING, OIL WEATHERING UNDER ARCTIC CONDITIONS AND ASSESSMENT OF OIL REMOVAL BY IN-SITUBURNING

2008 ◽  
Vol 2008 (1) ◽  
pp. 681-688 ◽  
Author(s):  
David Dickins ◽  
Per Johan Brandvik ◽  
John Bradford ◽  
Liv-Guri Faksness ◽  
Lee Liberty ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Sea Ice ◽  
Field Experiments ◽  
New Technologies ◽  
Time Window ◽  
The Arctic ◽  
Small Scale ◽  
Oil Removal ◽  
Arctic Conditions

ABSTRACT This paper describes the findings from an experimental spill of 3,400 liters of Statfjord crude under first-year sea ice in Svalbard, Norway in March 2006. The objectives were to:1. Test commercially available radar and acoustics systems for detecting oil spilled under ice.2. Document the weathering processes governing crude oil behaviour in ice.3. Confirm the effectiveness of in-situ burning as an oil removal strategy. The results of this project will be used in planning new Arctic oil exploration and development programs. With the growing awareness of the Arctic basin as a potentially important province for new oil and gas discoveries, there is a critical need to: (1) develop new technologies to detect and map spills under ice; (2) increase the understanding of oil behaviour in ice and: (3) continue to demonstrate the capabilities of in-situ burning as an important and safe Arctic response tool. Tank tests conducted in 2004 (Dickins et al., 2005) showed that radar systems could detect and map oil pools as thin as 2 to 3 cm under controlled conditions under model sea ice up to 40 cm thick. This field experiment created a much larger-scale spill under thicker 65 cm natural sea ice to further evaluate potential remote sensing systems as practical operational spill response tools. The findings of the 2006 experiment: (1) demonstrated for the first time the ability of ground penetrating radar to detect and map oil under natural sea ice from the surface; (2) documented oil weathering with a relatively warm ice sheet under spring conditions; and (3) confirmed the effectiveness of in situ burning as a primary oil removal strategy under Arctic conditions. Oil weathering results are discussed and compared with small-scale field experiments performed on Svalbard during the period 2003–2006. Low temperatures and lack of waves in ice act to reduce oil spreading, evaporation, emulsification and dispersion. As a result, the operational time window for several spill response strategies such as dispersants and in-situ burning may be significantly extended compared to oil spills in open water.

scholarly journals Advanced Remote Data Acquisition Using a Pop-Up Data Shuttle (PDS) to Report Data From Current- and Pressure-Recording Inverted Echo Sounders (CPIES)

2021 ◽  
Vol 8 ◽  
Author(s):  
Chanhyung Jeon ◽  
Jae-Hun Park ◽  
Maureen Kennelly ◽  
Erran Sousa ◽  
D. Randolph Watts ◽  
...  
Keyword(s):  
Data Acquisition ◽  
Field Experiments ◽  
Deep Ocean ◽  
Satellite System ◽  
Sea Surface ◽  
The Arctic ◽  
Pressure Recording ◽  
Ocean Surface Currents ◽  
Report Data ◽  
Ocean Environment

A current- and pressure-recording inverted echo sounder (CPIES) placed on the sea floor monitors aspects of the physical ocean environment for periods of months to years. Until recently, acoustic telemetry of daily-processed data was the existing method for data acquisition from CPIES without full instrument recovery. However, this approach, which requires positioning a ship at the mooring site and operator time, is expensive and time-consuming. Here, we introduce a new method of obtaining data remotely from CPIES using a popup-data-shuttle (PDS), which enables straightforward data acquisition without a ship. The PDS data subsampled from CPIES has 30–60 min temporal resolution. The PDS has a scheduled pop-up-type release system, so each data pod floats to the sea surface at a user-specified date and relays the recorded data via the Iridium satellite system. We demonstrated the capability of an array of PDS-CPIES via two successful field experiments in the Arctic Ocean. The data acquired through the PDS were in agreement with the fully recovered datasets. An example of the data retrieved from the PDS shows that time-varying signals of tides and high-frequency internal waves were well captured. GPS-tracked trajectories of the PDS floating free at the sea surface can provide insights into ice drift or ocean surface currents. This PDS technology provides an alternative method for remote deep-ocean mooring data acquisition.

scholarly journals Microbial dormancy and its impacts on Arctic terrestrial ecosystem carbon budget

2019 ◽  
Author(s):  
Junrong Zha ◽  
Qianlai Zhuang
Keyword(s):  
Greenhouse Gases ◽  
Carbon Budget ◽  
Terrestrial Ecosystem ◽  
Terrestrial Ecosystems ◽  
Carbon Dynamics ◽  
The Arctic ◽  
Earth System ◽  
Ecosystem Carbon ◽  
Rcp 8.5 ◽  
Earth System Models

Abstract. A large amount of soil carbon in the Arctic terrestrial ecosystems could be emitted as greenhouse gases in a warming future. However, lacking detailed microbial processes such as microbial dormancy in current biogeochemistry models might have biased the quantification of the regional carbon dynamics. Here the effect of microbial dormancy was incorporated into a biogeochemistry model to improve the quantification for the last and this century. Compared with the previous model without considering the microbial dormancy, the new model estimated the regional soils stored 75.9 Pg more C in the terrestrial ecosystems during the last century, and will store 50.4 Pg and 125.2 Pg more C under the RCP 8.5 and RCP 2.6 scenarios, respectively, in this century. This study highlights the importance of the representation of microbial dormancy in earth system models to adequately quantify the carbon dynamics in the Arctic.

Long-Term Ecological Research in the Arctic: Where Science Never Sleeps

2016 ◽  
Author(s):  
John E. Hobbie
Keyword(s):  
Mycorrhizal Fungi ◽  
Field Experiments ◽  
The Arctic ◽  
Ecological Research ◽  
Nitrogen And Phosphorus ◽  
Long Term Ecological Research ◽  
Bacterial Uptake ◽  
Project Data ◽  
Kinetics Of Uptake

When the Arctic (ARC) Long-Term Ecological Research (LTER) project began, I was an aquatic ecologist with experience in managing large projects in freshwaters and estuaries and a specialization in microbes. This project, which studies lakes, streams, and tundras, has greatly increased my breadth as an ecologist and allowed me to take part in terrestrial modeling, microbial studies in streams, and the role of soil mycorrhizal fungi in providing nutrients to many species of plants. As a mentor to several postdoctoral fellows, my LTER research has enabled me to learn about other fields such as the application of molecular biology to microbial ecology. The Arctic LTER project data, the long-term field experiments, and the facilities available at the University of Alaska field station brought me in contact with ecologists from many countries. One result of this association with experts was my coauthorship of a book on Arctic natural history aimed at communicating scientific knowledge to scientists and the general public unfamiliar with the Arctic (Huryn and Hobbie 2012). I have always collaborated extensively with many scientists and encouraged collaboration as the best way to carry out ecosystem research. The Arctic LTER project brought many opportunities to broaden the scope of my collaboration to include terrestrial ecologists and microbiologists. My PhD research was about year-round primary productivity of an Arctic lake but while on a postdoctoral fellowship at Uppsala University, Sweden, I switched to an emphasis on bacterial uptake kinetics in lakes. The techniques I helped develop in freshwater worked in the ocean and estuaries too (Hobbie and Williams 1984). In addition we developed the epifluorescence method for quantifying the abundance of planktonic bacteria. Our paper (Hobbie, Daley, and Jasper 1977) finally convinced oceanographers that bacteria are abundant (at 10⁹ per liter) and important. Recently, I have used my understanding of kinetics of uptake to analyze microbial activity in the soil. My Arctic expertise led to leadership of the aquatic part of the International Biological Program (IBP) at Barrow, Alaska, beginning in 1970. We (28 scientists, graduate students, and postdoctoral fellows) studied shallow ponds to quantify the carbon, nitrogen, and phosphorus cycles.

Sign in / Sign up

Export Citation Format

Share Document