From Mountain to Fjord 2012 – Science project summary
Climate warming since the Little Ice Age – The fjord record
The term “Little Ice Age” describes a climate cooling event with a maximum glacial advance at1750 A.D. The ultimate reason for this cold period is still to be explored.
Since 1750 A.D., the global climate is successively warming. How much of this warming is due to natural reasons? How much could be explained by human activity? The Intergovernmental Panel on Climate Change (e.g. IPCC 2007) has discussed this issue for almost two decades. However, the reasons of the climate warming are still heavily disputed.
Between 2005 and 2009, the “From Mountain to Fjord” students and others have analyzed Lake Hafslovatnet sediments for various environmental parameters. The sediment cores cover deposits throughout the whole Holocene, i.e. the last 10.000 years suggesting that the Little Ice Age defines a 1.000 year record of prolonged cold climate rather than indicating the Little Ice Age to being a short term event. The sediment record also suggests a continuous climate warming after the Little Ice Age maximum 1750 A.D. However, the sedimentation rates of the Lake Hafslovatnet are too low (0.3 mm/year) to reveal details on this late development (Kropp 2010).
The 2012 “From Mountain to Fjord” Science Project will focus on the climate development record of the last 500 years as stored in Sogndalsfjord sediments. The Sogndalsfjord has been investigated earlier for climate change of the last 50 years (Paetzel & Dale 2010). Recent “From Mountain to Fjord” research suggests high sedimentation rates in this fjord of about >1 mm/year (Kievits 2012), covering the last 500 years of sedimentation within the upper 50 cm of the sediment record.
The Sogndalsfjord sediments will be investigated for changes in sediment physical parameters (grain size, mineral matter), organic matter (terrestrial and marine), and microorganisms (diatoms, foraminifera). It will be the task of the 2012 “From Mountain to Fjord” Science Project to focus on the following questions:
- Do the Sogndalsfjord sediments reveal signals on climate warming during the last 262 years, i.e. since the maximum cold period of the Little Ice Age?
- Could these signals be used to identify possible natural and/or human induced reasons for the modern climate warming?
References
IPCC 2007: http://www.ipcc.ch/
Kievits L 2012: Volcanic ash dating of recent Sogndalsfjord sediments, Western Norway. Bachelor Thesis Environmental Sciences, Hogeschool van Hall Larenstein, Leeuwarden, Netherlands, 69pp.
Kropp A 2010: Reconstructing “Little Ice Age” processes based on the analysis of Hafslovatnet sediments, western Norway. Bachelor Thesis Life Science and Engineering, Fachhochschule Bingen, Bingen, Germany, 81pp.
Paetzel M & Dale T 2010: Climate proxies for recent fjord sediments in the inner Sognefjord region, western Norway. In: JA Howe, WEN Austin, M Forwick & M Paetzel (eds): Fjord System and Archives. Geological Society, London, Special Publication 244, 271-288.
Sist endra: Thursday 08 March 2012 9:26:38 am