Arctic2k


Arctic2k timeline
 Phase 1  Phase 2          Synthesis
         
 2008 - 2013 2014 2015 2016 May 2017


Overview
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Field work in innermost high alpine Svalbard with Endre Før Gjermundsen. Credit: Anne Hormes.

Arctic amplification of warming up to two times the global mean is observed and modelled due to the sea ice-albedo/ocean/snow surface albedo feedback effects (IPCC 2013). This trend has further accelerated during the past decade as evidenced by both the dramatic decrease of summer sea ice cover and the increased melt rates of glaciers (i.e. Comiso et al., 2008; Kohler et al., 2007). It is expected that anthropogenic global warming is and will be superimposed on natural variability. Unfortunately, most of the Arctic instrumental measurements only extend back to mid-20th century limiting our understanding of multi-decadal and –centennial spatial and temporal natural variability in the Arctic.

The PAGES Working Group (WG) on arctic climate during the last two millennia, Arctic2k, was launched in March 2008 (read article) to generate and synthesize high-resolution paleoclimate data to assess and elucidate both the timing and variability of the Arctic climate change during this period.

The group reached two successful milestones with the data collection and temperature reconstruction expressed in the benchmark paper by the PAGES2k Consortium paper (2013) and a subsequent revision of the Arctic2k proxy database (2014).

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Hjorthfjellet in Adventfjorden, Svalbard. Credit: Anne Hormes.


Learn more and participate

Subscribe to the Arctic2k mailing list here.

This group is open to anyone who is interested, to participate contact the group leader Hans Linderholm.



News

Post-meeting material from Arctic2k working group meeting at AGU 2016

The Arctic 2k hydroclimate poster in the CE session received some interest and we had a good group meeting.

Notes from meeting, attended by 25 people, taken by Björn Gunnarson:

We started off with a short summary of the recent efforts of Arctic2k, focusing on the works to be presented in the Climate of the Past special issue. We heard short presentations of these papers:

- Marie Nicolle talked about a regional reconstructions of subarctic temperatures in a 2k context.
- Johannes Werner gave a short presentation about the field temperature reconstruction.
- Gifford Miller talked about how dating of dead pieces of vegetation in the Arctic can be used to constrain glacier fluctuations, which could be a useful indicator for temperature and/or precipitation (depending on what drives glacier dynamics).
- I talked briefly about the hydroclimate review paper, focusing on the lack of data, especially over Eurasia.

Outside the CP SI, we had a presentation by Reik Donner about Non-linear time series analysis weighted proxy’s w.r.t nodes and correlations.

Then there were discussions on how different proxies represents different seasonality. Some proxies are used for temperatures and often the same proxies are also used for precip/moisture variability. The precip/moisture data are usually much more spatially heterogeneous compared with temperature changes, and therefore could not represent large-scale variations. How should we combine annually resolved proxies (tree-rings) with lower resolution proxies (lake sediments)?

It was agreed that all available data to be used in the hydroclimate review paper should be put in the dedicated dropbox.

Lastly, the next step of PAGES 2K, phase III, was briefly presented. One aim of the next phase is to better understand the driving mechanism (trans-regional) on climate variability (inter-annual to centennial time frames). The participants were encouraged to think about project ideas (Hans gave an example where the coupling of arctic and mid-latitude climates could be explored). Phase III will likely have its “kick off” at the 5th PAGES OSM, in Zaragoza from 9-13 May 2017.

Published: 17 January 2016

 

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Lake sediment coring in spring 2008 on Kongressvatnet, Svalbard with Willem van der Bilt, Al Werner and Jørgen Haagensli. Credit: Anne Hormes.

 

 

New people are working in the Arctic2k group!

Read more ...

Published: 19 June 2014


The PAGES Arctic2k network needs your input!

Precipitation/humidity records are still severely underrepresented in the Arctic2k database. While more substantial than for precipitation, some regions, such as the Russian or Canadian Arctic still yield only very few records.

The published record should fulfill the following criteria to be included in the database:

1. Demonstrated plausible mechanistic relation to climate, but not necessarily quantitative

2. At least one numerical age per 500-year interval  (a qualitative age-depth model with error bands of
<100 years will be considered)

3. At least one analysis every 200 years

4. Must span at least 500 years during the past 2k

5. Must be published in a peer-reviewed publication

6. Must be made available through the PAGES2k database at NOAA when being used for a published result in the framework of PAGES2k

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Lina Gislefoss sampling late Holocene erratic boulders outside the Little Ice Age moraine in Hornsund, Svalbard. Credit: Anne Hormes.

If you are aware of records that fulfill these criteria, please contact the data managers (Dmitry Divine and Johannes Werner) to submit your data to the Arctic2k database. The data managers will instruct you on how to submit your record in the best format. All new data will first be used internally by the PAGES 2k Network and be archived publicly once a product is published.

Published: 16 June 2014

 

Tell us about your ongoing projects

Please, let us know about your ongoing projects for the News section of our Arctic2k web site.

Published: 16 June 2014

 

 

 

References

Comiso, J.C., Parkinson, C.L., Gersten, R. and Stock, L., (2008) Accelerated decline in the Arctic sea ice cover, Geophysical Research Letters, 35, doi:10.1029/2007GL031972.

IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F. et al. (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1535 pp.

Kohler, J., James, T.D., Murray, T., Nuth, C., Brandt, O., Barrand, N.E., Aas, H.F. and Luckman, A., (2007) Acceleration in thinning rate on western Svalbard glaciers, Geophysical Research Letters, 34, doi:10.1029/2007GL030681.

PAGES 2k Consortium (2013) Continental-scale temperature variability during the past two millennia. Nat Geosci 6: 339-346