Skip header and navigation

Refine By

635 records – page 1 of 64.

A 300-million-year record of atmospheric carbon dioxide from fossil plant cuticles.

https://arctichealth.org/en/permalink/ahliterature95961
Source
Nature. 2001 May 17;411(6835):287-90
Publication Type
Article
Date
May-17-2001
Author
Retallack G J
Author Affiliation
Department of Geological Sciences, University of Oregon, Eugene 97403-1272, USA. gregr@darkwing.uoregon.edu
Source
Nature. 2001 May 17;411(6835):287-90
Date
May-17-2001
Language
English
Publication Type
Article
Keywords
Atmosphere - chemistry
Carbon Dioxide - metabolism
Cold Climate
Fossils
Ginkgo biloba - cytology - growth & development - metabolism
Greenhouse Effect
Ice
Methane - metabolism
Phylogeny
Plant Leaves - cytology - growth & development - metabolism
Plants, Medicinal
Pollen
Seasons
Water - metabolism
Abstract
To understand better the link between atmospheric CO2 concentrations and climate over geological time, records of past CO2 are reconstructed from geochemical proxies. Although these records have provided us with a broad picture of CO2 variation throughout the Phanerozoic eon (the past 544 Myr), inconsistencies and gaps remain that still need to be resolved. Here I present a continuous 300-Myr record of stomatal abundance from fossil leaves of four genera of plants that are closely related to the present-day Ginkgo tree. Using the known relationship between leaf stomatal abundance and growing season CO2 concentrations, I reconstruct past atmospheric CO2 concentrations. For the past 300 Myr, only two intervals of low CO2 (2,000 p.p.m.v.) concentrations. These results are consistent with some reconstructions of past CO2 (refs 1, 2) and palaeotemperature records, but suggest that CO2 reconstructions based on carbon isotope proxies may be compromised by episodic outbursts of isotopically light methane. These results support the role of water vapour, methane and CO2 in greenhouse climate warming over the past 300 Myr.
Notes
Comment In: Nature. 2001 May 17;411(6835):247-811357108
PubMed ID
11357126 View in PubMed
Less detail

A 300-Year High-Resolution Greenland Ice Record of Large-Scale Atmospheric Pollution by Arsenic in the Northern Hemisphere.

https://arctichealth.org/en/permalink/ahliterature308683
Source
Environ Sci Technol. 2019 Nov 19; 53(22):12999-13008
Publication Type
Journal Article
Date
Nov-19-2019
Author
Khanghyun Lee
Changhee Han
Sang-Bum Hong
Seong-Joon Jun
Yeongcheol Han
Cunde Xiao
Zhiheng Du
Soon Do Hur
Jong Ik Lee
Claude F Boutron
Sungmin Hong
Author Affiliation
Korea Polar Research Institute , 26 Songdomirae-ro , Yeonsu-gu, Incheon 21990 , Korea.
Source
Environ Sci Technol. 2019 Nov 19; 53(22):12999-13008
Date
Nov-19-2019
Language
English
Publication Type
Journal Article
Keywords
Air Pollutants
Arsenic
China
Environmental monitoring
Europe
Greenland
Ice
North America
Abstract
We report the first high-resolution record of arsenic (As) observed in Greenland snow and ice for the periods 1711-1970 and 2003-2009 AD. The results show well-defined large-scale atmospheric pollution by this toxic element in the northern hemisphere, beginning as early as the 18th century. The most striking feature is an abrupt, unprecedented enrichment factor (EF) peak in the late 1890s, with an ~30-fold increase in the mean value above the Holocene natural level. Highly enriched As was evident until the late 1910s; a sharp decline was observed after the First World War, reaching a minimum in the early 1930s during the Great Depression. A subsequent increase lasted until the mid-1950s, before decreasing again. Comparisons between the observed variations and Cu smelting data indicate that Cu smelting in Europe and North America was the likely source of early anthropogenic As in Greenland. Despite a significant reduction of ~80% in concentration and ~60% in EF from the 1950s to the 2000s, more than 80% of present-day As in Greenland is of anthropogenic origin, probably due to increasing As emissions from coal combustion in China. This highlights the demand for the implementation of national and international environmental regulations to further reduce As emissions.
PubMed ID
31603318 View in PubMed
Less detail

A 700-year paleoecological record of boreal ecosystem responses to climatic variation from Alaska.

https://arctichealth.org/en/permalink/ahliterature85780
Source
Ecology. 2008 Mar;89(3):729-43
Publication Type
Article
Date
Mar-2008
Author
Tinner Willy
Bigler Christian
Gedye Sharon
Gregory-Eaves Irene
Jones Richard T
Kaltenrieder Petra
Krähenbühl Urs
Hu Feng Sheng
Author Affiliation
Institute of Plant Sciences and Oeschger Center for Climate Change Research, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland. willy.tinner@ips.unibe.ch
Source
Ecology. 2008 Mar;89(3):729-43
Date
Mar-2008
Language
English
Publication Type
Article
Keywords
Alaska
Climate
Diatoms
Ecosystem
Fires
Forestry
Fossils
Geologic sediments
Greenhouse Effect
Ice Cover
Plant Physiology
Pollen
Time Factors
Trees
Abstract
Recent observations and model simulations have highlighted the sensitivity of the forest-tundra ecotone to climatic forcing. In contrast, paleoecological studies have not provided evidence of tree-line fluctuations in response to Holocene climatic changes in Alaska, suggesting that the forest-tundra boundary in certain areas may be relatively stable at multicentennial to millennial time scales. We conducted a multiproxy study of sediment cores from an Alaskan lake near the altitudinal limits of key boreal-forest species. Paleoecological data were compared with independent climatic reconstructions to assess ecosystem responses of the forest tundra boundary to Little Ice Age (LIA) climatic fluctuations. Pollen, diatom, charcoal, macrofossil, and magnetic analyses provide the first continuous record of vegetation fire-climate interactions at decadal to centennial time scales during the past 700 years from southern Alaska. Boreal-forest diebacks characterized by declines of Picea mariana, P. glauca, and tree Betula occurred during the LIA (AD 1500-1800), whereas shrubs (Alnus viridis, Betula glandulosa/nana) and herbaceous taxa (Epilobium, Aconitum) expanded. Marked increases in charcoal abundance and changes in magnetic properties suggest increases in fire importance and soil erosion during the same period. In addition, the conspicuous reduction or disappearance of certain aquatic (e.g., Isoetes, Nuphar, Pediastrum) and wetland (Sphagnum) plants and major shifts in diatom assemblages suggest pronounced lake-level fluctuations and rapid ecosystem reorganization in response to LIA climatic deterioration. Our results imply that temperature shifts of 1-2 degrees C, when accompanied by major changes in moisture balance, can greatly alter high-altitudinal terrestrial, wetland, and aquatic ecosystems, including conversion between boreal-forest tree line and tundra. The climatic and ecosystem variations in our study area appear to be coherent with changes in solar irradiance, suggesting that changes in solar activity contributed to the environmental instability of the past 700 years.
PubMed ID
18459336 View in PubMed
Less detail

Abundance Estimates of Ice-Associated Seals: Bering Seas Populations that Inhabit the Chukchi Sea During the Open-Water Period. Final report.

https://arctichealth.org/en/permalink/ahliterature303415
Source
BOEM Report 2016-077. U.S. Department of the Interior, Bureau of Ocean Energy Management, Alaska Outer Continental Shelf Region with the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service. [122] pp.
Publication Type
Report
Date
2016
BOEM Report 2016-077 i Abundance Estimates of Ice-Associated Seals: Bering Sea Populations that Inhabit the Chukchi Sea During the Open-Water Period FINAL REPORT By Peter L. Boveng, Michael F. Cameron, Paul B. Conn, and Erin E. Moreland Marine Mammal Laboratory
  1 document  
Author
Boveng, P.L.
Cameron, M.F.
Conn, Paul B.
Moreland, E.E.
Source
BOEM Report 2016-077. U.S. Department of the Interior, Bureau of Ocean Energy Management, Alaska Outer Continental Shelf Region with the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service. [122] pp.
Date
2016
Language
English
Geographic Location
U.S.
Publication Type
Report
File Size
4812161
Keywords
Alaska
Bering Sea
Chukchi Sea
Bearded seal
Ribbon seal
Ringed seal
Spotted seal
Ice-associated seals
Abundance
Distribution
Aerial survey
Sea of Okhotsk
Arctic
Documents

Final-Report_2016-077_M12PG00017_Draft_2017-02-16_ReducedSize.pdf

Read PDF Online Download PDF
Less detail

Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss

https://arctichealth.org/en/permalink/ahliterature275999
Source
Geophysical Research Letters. 2008 Jun;35(11):1-6
Publication Type
Article
Date
Jun-2008
Author
Lawrence, DM
Slater, AG
Tomas, RA
Holland, MM
Deser, C
Source
Geophysical Research Letters. 2008 Jun;35(11):1-6
Date
Jun-2008
Language
English
Publication Type
Article
Keywords
Albedo
Arctic sea ice
Arctic warming
Land temperature
Permafrost
Abstract
Coupled climate models and recent observational evidence suggest that Arctic sea ice may undergo abrupt periods of loss during the next fifty years. Here, we evaluate how rapid sea ice loss affects terrestrial Arctic climate and ground thermal state in the Community Climate System Model. We find that simulated western Arctic land warming trends during rapid sea ice loss are 3.5 times greater than secular 21st century climate-change trends. The accelerated warming signal penetrates up to 1500 km inland and is apparent throughout most of the year, peaking in autumn. Idealized experiments using the Community Land Model, with improved permafrost dynamics, indicate that an accelerated warming period substantially increases ground heat accumulation. Enhanced heat accumulation leads to rapid degradation of warm permafrost and may increase the vulnerability of colder permafrost to degradation under continued warming. Taken together, these results imply a link between rapid sea ice loss and permafrost health.
Less detail

[Accidental child deaths by falls through ice in 1973-1977]

https://arctichealth.org/en/permalink/ahliterature40485
Source
Ugeskr Laeger. 1982 Mar 15;144(11):830-2
Publication Type
Article
Date
Mar-15-1982
Author
L. Bjerrum
P. Bjerrum
Source
Ugeskr Laeger. 1982 Mar 15;144(11):830-2
Date
Mar-15-1982
Language
Danish
Publication Type
Article
Keywords
Adolescent
Child
Child, Preschool
Denmark
Drowning - epidemiology
English Abstract
Humans
Ice
Infant
Male
PubMed ID
7101518 View in PubMed
Less detail

Activity and diversity of methane-oxidizing bacteria along a Norwegian sub-Arctic glacier forefield.

https://arctichealth.org/en/permalink/ahliterature299197
Source
FEMS Microbiol Ecol. 2018 05 01; 94(5):
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
05-01-2018
Author
Alejandro Mateos-Rivera
Lise Øvreås
Bryan Wilson
Jacob C Yde
Kai W Finster
Author Affiliation
Department of Biology, University of Bergen, NO-5020, Bergen, Norway.
Source
FEMS Microbiol Ecol. 2018 05 01; 94(5):
Date
05-01-2018
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Arctic Regions
Biodiversity
High-Throughput Nucleotide Sequencing
Ice Cover - microbiology
Methane - metabolism
Methylococcaceae - classification - genetics - isolation & purification
Norway
Soil Microbiology
Abstract
Methane (CH4) is one of the most abundant greenhouse gases in the atmosphere and identification of its sources and sinks is crucial for the reliability of climate model outputs. Although CH4 production and consumption rates have been reported from a broad spectrum of environments, data obtained from glacier forefields are restricted to a few locations. We report the activities of methanotrophic communities and their diversity along a chronosequence in front of a sub-Arctic glacier using high-throughput sequencing and gas flux measurements. CH4 oxidation rates were measured in the field throughout the growing season during three sampling times at eight different sampling points in combination with laboratory incubation experiments. The overall results showed that the methanotrophic community had similar trends of increased CH4 consumption and increased abundance as a function of soil development and time of year. Sequencing results revealed that the methanotrophic community was dominated by a few OTUs and that a short-term increase in CH4 concentration, as performed in the field measurements, altered slightly the relative abundance of the OTUs.
PubMed ID
29617984 View in PubMed
Less detail
Publication Type
Interactive/Multimedia
  1 website  
Author Affiliation
Alaska Sea Grant
Language
English
Geographic Location
U.S.
Publication Type
Interactive/Multimedia
Digital File Format
Web site (.html, .htm)
Keywords
One Health
Northern communities
Vulnerability & Adaptation
Animals
Climate change
Permafrost
Introduced species
Ice
Ecosystem
Floods
Freezing
Abstract
Seventeen-minute video produced by Alaska Sea Grant and NOAA Alaska Region.
Online Resources
Less detail

Advancing Oil Spill Response in Ice-Covered Waters.

https://arctichealth.org/en/permalink/ahliterature301424
Source
Prince William Sound Oil Spill Recovery Institute and United States Arctic Research Commission. 19 pages.
Publication Type
Report
Date
2004
on pages 6 - 7, at the center of the publication. pages referenced Fig. 1 Schematic view of possible oil configurations in ice . . . . . . . . . . . . . . . . . . . . . . . . . .2, 8 Fig. 2 Man-made ice field at the Ohmsett test tank
  1 document  
Author
DF Dickins Associates Ltd
Source
Prince William Sound Oil Spill Recovery Institute and United States Arctic Research Commission. 19 pages.
Date
2004
Language
English
Publication Type
Report
File Size
1125061
Keywords
Sea ice
Oil spills
Response strategies
Abstract
The objective of this project is to identify programs and research and development projects that improve the ability of responders to deal with accidental oil spills in fresh or salt-water marine environments where there is ice. This includes spills that occur on top of or underneath solid, stable ice extending out from shore (land-fast), into an area of drifting ice floes (pack ice), or onto an ice-covered shoreline.
Documents
Less detail

635 records – page 1 of 64.