Thursday, January 02, 2020



ARCTIC

A new study finds research gaps in environmental science disciplines across the Arctic
Harsh environments remain poorly sampled
More sampling is needed particularly in the Canadian Arctic Archipelago, northern Greenland, northern Taimyr, and central and eastern Siberia.
UNIVERSITY OF HELSINKI



IMAGE
IMAGE: HARSH ARCTIC ENVIRONMENTS LIKE THIS REMAIN POORLY SAMPLED AND REQUIRE TARGETED RESEARCH IN THE FUTURE. view more 
CREDIT: JULIA KEMPPINEN

Global warming is driving rapid environmental change in the Arctic. "To understand these changes, field measurements that adequately represent environmental variation across the Arctic as a whole are crucial", says PhD student Anna-Maria Virkkala from the University of Helsinki.
A new study by researchers from University of Helsinki and Lund University shows that northern Arctic regions remain under-sampled and provides detailed maps of potential new sampling locations for each environmental science discipline across the Arctic.

The changing Arctic requires a sampling strategy for the future
Doing field work in the harsh Arctic conditions is not easy. Resources and accessibility strongly constrain Arctic research. Understanding what kind of conditions and regions remain under-studied is important when researchers plan new field campaigns.
However, studies dealing with the representativeness of sampling have been conducted mainly for very specific fields, or in smaller regions. Thus, the current state of field sampling across broad environmental science disciplines across the Arctic has not been fully understood.
A literature database and open spatial data sets as a tool to map the representativeness of sampling
"We utilize an existing literature database of around 1 800 field studies across the Arctic", says Dan Metcalfe, a senior lecturer in Lund University. This database contains information about the field sampling locations and citations, including their primary discipline/s within environmental sciences featured in the article.
Open spatial data sets describing topography, vegetation, and soils were used to characterize the environmental conditions of each sampling location. "The availability of these data sets has increased during the past decade which allows us to explore the environmental coverage of Arctic field sampling comprehensively", says a Post-Doc researcher Hakim Abdi from Lund University.

New field studies are needed in the northernmost Arctic regions
The study shows that more research is needed particularly in the Canadian Arctic Archipelago, northern Greenland, northern Taimyr, and central and eastern Siberia. These under-sampled regions are characterized by cold soils and climate and modest vegetation cover. Many of these regions are predicted to experience rapid permafrost thaw and vegetation shifts due to global warming in the future. The lack of data from these conditions suggests that we do not necessarily understand the whole range of changes that the global warming might cause.
Differences in sampling across environmental science disciplines
There are differences in the representativeness of sampling locations across environmental science disciplines. Sampling locations in Botany and Biogeochemistry cover environmental gradients the best, and Microbiology, Meteorology, Geosciences and Geographic Information Systems / Remote Sensing / Modeling have the largest research gaps across the Arctic. Although northern Alaska and Fennoscandia remained the best sampled regions, research gaps were found even in central Arctic Alaska or southern Arctic Fennoscandia in some disciplines.
Let's keep exploring the Arctic together
Luckily, many of these under-sampled regions are close to existing infrastructure (https://eu-interact.org/field-sites/), so making a change is possible. "We hope these results will help prioritize future research efforts across all environmental science disciplines, thus increasing our knowledge about the Arctic environmental change", summarizes Professor Miska Luoto from University of Helsinki.
###
Reference: Anna-Maria Virkkala, Hakim Abdi, Miska Luoto and Dan Metcalfe. Identifying multidisciplinary research gaps across Arctic terrestrial gradients. Environmental Research Letters. doi.org/10.1088/1748-9326/ab4291
Contact: Anna-Maria Virkkala, anna-maria.virkkala@helsinki.fi, +358 503116183

New study estimates the global extent of river ice loss as Earth warms

This decline will have economic and environmental consequences
UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL



IMAGE
IMAGE: ICE COVER ON THE YUKON RIVER APPROACHING ITS CONFLUENCE WITH THE TANANA RIVER IN ALASKA. view more 
CREDIT: COURTESY LANDSAT IMAGERY/NASA GODDARD SPACE FLIGHT CENTER AND U.S. GEOLOGICAL SURVEY

More than half of Earth's rivers freeze over every year. These frozen rivers support important transportation networks for communities and industries located at high latitudes. Ice cover also regulates the amount of greenhouse gasses released from rivers into Earth's atmosphere.
A new study from researchers in the University of North Carolina at Chapel Hill Department of Geological Sciences found that annual river ice cover will decline by about six days for every one degree Celsius increase in global temperatures. This decline will have economic and environmental consequences. The study, "The past and future of global river ice," was published Jan. 1 in the journal Nature. It is the first study to look at the future of river ice on a global scale.
"We used more than 400,000 satellite images taken over 34 years to measure which rivers seasonally freeze over worldwide, which is about 56% of all large rivers," said Xiao Yang, a postdoctoral scholar in the UNC-Chapel Hill geological sciences department and lead author on the paper. "We detected widespread declines in monthly river ice coverage. And the predicted trend of future ice loss is likely to lead to economic challenges for people and industries along these rivers, and shifting seasonal patterns in greenhouse gas emissions from the ice-affected rivers."
The team also looked at changes to river ice cover in the past and modeled predicted changes for the future. Comparing river ice cover from 2008-2018 and 1984-1994, the team found a monthly global decline ranging from .3 to 4.3 percentage points. The greatest declines were found in the Tibetan Plateau, eastern Europe and Alaska.
"The observed decline in river ice is likely to continue with predicted global warming," the study explains.
For the future, the team compared expected river ice cover through 2009-2029 and 2080-2100. Findings showed monthly declines in the Northern Hemisphere ranging from 9-15% in the winter months and 12-68% during the spring and fall. The Rocky Mountains, northeastern United States, eastern Europe and Tibetan Plateau are expected to take the heaviest impact.
"Ultimately, what this study shows is the power of combining massive amounts of satellite imagery with climate models to help better project how our planet will change," said UNC-Chapel Hill Associate Professor of global hydrology Tamlin Pavelsky.
###
George Allen, assistant professor of geography at Texas A&M University, worked with Xiao and Tamlin on the study. NASA's Jet Propulsion Laboratory funded the work.

Replacing one gas with another helps efficiently extract methane from permafrost

SKOLKOVO INSTITUTE OF SCIENCE AND TECHNOLOGY (SKOLTECH)
Scientists from Skoltech and Heriot-Watt University proposed extracting methane by injecting flue gas into permafrost hydrate reservoirs. Since the flue gas contains carbon dioxide, the new technology will also contributes to reduction of this green house gas in the Arctic atmosphere. The results of their study were published in the journal Scientific Reports.
The Russian Arctic is actively developing due to exploitation of recently discovered oil and gas fields. However, operations in the Arctic region face numerous geological challenges. One of the most serious of them is formation of gas hydrates in frozen rock mass. Gas hydrates are ice-like crystalline structures formed by water and gas molecules. Their accumulations strongly hinders oil and gas field development and triggers spontaneous methane emissions into the atmosphere on the Arctic coast and shelf.
The scientists from the Skoltech Center for Hydrocarbon Recovery (CHR) and from Heriot-Watt University (Edinburgh, Scotland) developed a unique method for extracting methane from permafrost gas-hydrates by injecting flue gases, generated by fuel combustion. The main sources of flue gas are waste gases from coal-burning power plants and metallurgical plants and other industrial facilities.
The research team has found optimal injection conditions and identified the effect of flue gases on the efficiency of methane recovery. It is important to emphasize that flue gas contains considerable amount of green-house carbon dioxide, that will also be buried subsurface. The carbon dioxide forms hydrate replacing the original methane hydrate. The new technology is essential for development of the hydrocarbon fields in the highly sensitive Arctic environment.
"Our approach not only helps extract methane and prevent its free release into the atmosphere but also reduce carbon dioxide emissions. I would say our method offers a double dividend in terms of environmental safety," says Leading Research Scientist at CHR, Evgeny Chuvilin.
###

No comments: