Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

50 Arctic lakes show dramatic effects of climate warming

09.04.2003


“Bellwether” of what’s to come farther south, say Queen’s researchers

Dramatic clues to North American climate change have been discovered by a team of Queen’s University scientists in the bottom of 50 Arctic lakes.

Using innovative techniques that enable them to collect historic evidence from fossilized algae in lake bottom sediment, the researchers have found signs of marked environmental changes in a variety of lakes of different depths and composition, within a 750-km region bordering the northern tree-line. The changes are a signal of things to come in the rest of North America, say the Queen’s paleolimnologists.



“We’re seeing a significant, regional change in the ecology of these lakes over the past two centuries that is consistent with warmer conditions,” says Dr. John Smol, Canada Research Chair in Environmental Change and co-head of the university’s Paleoecological Environmental Assessment and Research Laboratory (PEARL). Dr. Smol conducted the study with Dr. Kathleen Rühland and student Alisha Priesnitz of Queen’s Biology Department.

“Because the Arctic is a very vulnerable environment and usually the first area of the continent to show signs of environmental change – often to the greatest degree – it’s considered a bellwether of what will happen elsewhere,” says Dr. Rühland. “These are important signals that all of us should be heeding: the lakes’ sedimentary records have tracked marked and directional ecosystem changes.”

The Queen’s study will be published this month in the international journal Arctic, Antarctic, and Alpine Research.

To reconstruct past environmental trends, the team used fossil markers (tiny algal cells) preserved in lake sediment. Sediment cores were collected by helicopter from the 50 lakes, in an area from Yellowknife, NWT, in the Boreal forest area towards the Bering Sea in the Arctic tundra. For each lake, they compared fossilized algae preserved in the top, most recent sediment layer with those from the bottom, pre-industrial layer dating back about 200 years.

They found that the aquatic habitat of today is much different from that of pre-industrial times. More fossils of the type that live in open water environments were found in the top (most recent) layer of sediment – an indication that these lakes have less ice cover and a longer growing season that would alter important lakewater properties such as light availability and the way lakes stratify, as a result of warming. This marked a major ecological shift in the lakes that coincides with a period of increased human industrial activities and emissions in more southern regions.

Earlier PEARL studies in the High Arctic tundra had indicated major changes in the different layers of fossils associated with climate warming. The new findings bring the effects of climate change closer to populated areas. “The logical extension was to see if tree-line lakes also show these dramatic changes, and this study confirms that the impact is even greater than previously documented,” says Dr. Rühland. “We believe that the consequences of greenhouse gas emissions, in the form of climate change, are already having a notable impact on the Arctic environment.”

As well as affecting plant and animal life in this region, melting permafrost and less ice cover are already beginning to have repercussions on human concerns such as transportation, housing, and even sovereignty issues.

Last year an entire Nunavik community was relocated by the Quebec government after melting permafrost caused houses to slide from their foundations. Other researchers have found evidence that ocean ice is thinning, which could have future implications for intercontinental transportation routes.

“Until recently, no one was reconstructing Arctic climates in this way, because the technology didn’t exist,” says Dr. Smol. “Now that we can, in essence, reconstruct the past through this indirect technique, we’re filling in gaps in our knowledge and finding answers to many ecological and environmental questions that have great significance for the future.”

PLEASE NOTE: Colour graphics of the modern and pre-industrial diatoms are available in JPEG format. To receive a copy of the Queen’s study, contact:

-30-

Nancy Dorrance, Queen’s News & Media Services, 613.533.2869
Lorinda Peterson, Queen’s News & Media Services, 613.533.6000 ext. 77559

Attention broadcasters: Queen’s now has facilities to provide broadcast quality audio and video feeds. For television interviews, we can provide a live, real-time double ender from Kingston fibre optic cable. Please call for details.

Nancy Dorrance | Queen´s University
Further information:
http://qnc.queensu.ca/story_loader.php?id=3e917778b9960

More articles from Ecology, The Environment and Conservation:

nachricht Road access for all would be costly, but not so much for the climate
10.07.2020 | Potsdam-Institut für Klimafolgenforschung

nachricht Innovative grilling technique improves air quality
01.07.2020 | Fraunhofer Institute for Building Physics IBP

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The spin state story: Observation of the quantum spin liquid state in novel material

New insight into the spin behavior in an exotic state of matter puts us closer to next-generation spintronic devices

Aside from the deep understanding of the natural world that quantum physics theory offers, scientists worldwide are working tirelessly to bring forth a...

Im Focus: Excitation of robust materials

Kiel physics team observed extremely fast electronic changes in real time in a special material class

In physics, they are currently the subject of intensive research; in electronics, they could enable completely new functions. So-called topological materials...

Im Focus: Electrons in the fast lane

Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.

Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....

Im Focus: The lightest electromagnetic shielding material in the world

Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.

Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...

Im Focus: Gentle wall contact – the right scenario for a fusion power plant

Quasi-continuous power exhaust developed as a wall-friendly method on ASDEX Upgrade

A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

International conference QuApps shows status quo of quantum technology

02.07.2020 | Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

 
Latest News

X-ray scattering shines light on protein folding

10.07.2020 | Life Sciences

Looking at linkers helps to join the dots

10.07.2020 | Materials Sciences

Surprisingly many peculiar long introns found in brain genes

10.07.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>